Claire E Lazareth
email: claire.lazareth@bondy.ird.fr

Grégory Lasne

Luc Ortlieb

Growth anomalies in Protothaca thaca (Mollusca, Veneridae) shells as markers of ENSO conditions

INTRODUCTION

Bivalve shell growth is a step by step process. Growth layers are successively added at the edge and inner surface of the growing shell. The thickness of the increments and the frequency at which they are added are governed not only by animal physiology (e.g. reproduction, ontogeny), but also by environmental variations (e.g. tidal cycle, water temperature, storm events, food availability). The study of shell microstructure periodicities, sclerochronology, can thus give information on both life history and environmental variations that occurred throughout the lifetime of the animal (reviews by [START_REF] Lutz | Growth patterns within the molluscan shell, an overview[END_REF], Richardson 2001). Yearly to daily periodicities can be observed in the succession of shell increments. Growth rings (also named 'checks' or 'breaks') are formed in the shell when growth is redu-ced or stopped during temperature extremes, e.g. in summer and/or winter (e.g. [START_REF] Jones | Marking time with bivalve shells: oxygen isotopes and season of annual increment formation[END_REF]. The growth rings can be counted to deduce the lifespan of fossil and living specimens [START_REF] Jones | Sclerochronology: reading the record of the molluscan shell[END_REF] and references therein). Many bivalve species deposit microgrowth increments, usually named 'daily growth increments'; their width and number per year generally decreases with ontogeny [START_REF] Hall | Shell growth of Tivela stultorum (Mawe, 1826) and Callista chione (Linnaeus, 1758) (Bivalvia): annual periodicity, latitudinal differences, and diminution with age[END_REF][START_REF] Jones | Annual growth increments in shells of Spisula solidissima record marine temperature variability[END_REF], Tanabe 1988). Formation of daily increments and some of their variability in width are related to tidal rhythms (e.g. Richardson 2001, Schöne et al. 2002a, 2003) and temperature [START_REF] Kennish | Effects of thermal discharges on the microstructural growth of Mercenaria mercenaria[END_REF][START_REF] Jones | Annual growth increments in shells of Spisula solidissima record marine temperature variability[END_REF][START_REF] Goodwin | Cross-calibration of daily growth increments, stable isotope variation, and temperature in the Gulf of California bivalve mollusk Chione cortezi: implications for paleoenvironmental analysis[END_REF], Schöne et al. 2005). Schöne et al. (2002b) used age-detrending methods and Fourier filters to remove the ontogenic trend and tidal cycles from daily growth data in Chione cortezi and extract a sea surface temperature (SST) signal.

ABSTRACT: Environmental variations can be recorded in bivalve shells, and this proxy information can be crucial for paleoceanographic studies in regions where other proxies (e.g. corals) are absent. We present the first sclerochronological study of Protothaca thaca (Mollusca, Veneridae), a common upper subtidal bivalve, characterized by a high temperature tolerance, from the SE Pacific Ocean (12 to 45°S). P. thaca is present in archaeological deposits and Holocene marine terraces, making it a potentially useful paleo-environmental recorder, particularly in respect to El Niño Southern Oscillation (ENSO) reconstructions. The sclerochronological analysis of recent P. thaca shells from Peru and Chile was done by microscopy of thin sections and acetate peel replicates; it shows that a clear 'summer check' (SC) is formed in the shell when sea surface temperature (SST) exceeds 18°C for several weeks. Under La Niña conditions in summer, SCs can be absent due to lower SST and enhanced productivity. During the strong 1997-1998 El Niño, long-lasting high summer SST produced an SC > 520 µm wide. The relative width of SC on fossil shells may thus be an indicator of paleo-ENSO events. Our sclerochronological analysis has established a temporal framework in P. thaca shells, providing precise time-series analytical profiles, which is a prerequisite for future calibration of geochemical proxies.

KEY WORDS: Bivalve • Protothaca thaca • Peru • Chile • Sclerochronology • El Niño Southern Oscillation

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The SE Pacific region is of particular importance for understanding the El Niño phenomenon. El Niño events along the Peruvian and north Chilean coasts result in a considerable increase in SST; e.g. during the very strong 1982-1983 El Niño, SST rose by 10°C during several weeks [START_REF] Arntz | The two faces of El Niño 1982-1983[END_REF]. At present, marine sediment records off Peru and Chile do not provide sufficient resolution to document such short term climatic events. Corals could provide high-resolution proxy records of El Niño occurrences, but in the cool waters of the Humboldt Current there are no coral species that can be used for paleo-environmental reconstructions.

Mollusc shells could supply a proxy record of El Niño events. The presence of easily readable shell growth anomalies may provide evidence of ENSO related events for specific Holocene periods. Bivalve shells (Chione subrugosa and Trachycardium procerum) from Peru have recorded the 1982-1983 El Niño both in the shell microstructure (growth anomaly) and in the shell isotopic signature (Rollins et al. 1987, Perrier et al. 1994). Similar features have been observed in fossil T. procerum shells and this is interpreted as reflecting El Niño occurrences during the Mid-Holocene period (Perrier et al. 1994). [START_REF] Carré | Strong El Niño events during the early Holocene: stable isotope evidence from Peruvian sea shells[END_REF] determined δ 18 O in archaeological Mesodesma donacium shells to study early Holocene El Niño events. However, the use of M. donacium shells as archive of El Niño event occurrences is problematic, since this species is particularly sensitive to temperature increases. M. donacium populations suffered high mortality during the 1982-1983 and 1997-1998 El Niño events [START_REF] Arntz | Effects of El Niño 1982-83 on benthos, fish and fisheries off the South American Pacific coast[END_REF][START_REF] Barriga | Impacts of El Niño and La Niña events on the populations of clams (Mesodesma donacium, Lamarck 1818) along the Southern Peruvian coast[END_REF].

Protothaca thaca may be a more appropriate environmental and paleo-environmental recorder, because its high temperature tolerance (Urban 1994) makes it one of the most resistant species to the effects of El Niño events in the SE Pacific region. A study of P. thaca shell geochemistry [START_REF] Jouhari | Calibration of the oxygen isotopic composition of bivalve shells (Protothaca thaca, Veneridae) from the northern Chile coast[END_REF] indicates that the 1997-1998 El Niño was registered in the stable oxygen isotope composition of the carbonate. Moreover, P. thaca is found in Holocene archaeological deposits of Peru (Reitz 1988[START_REF] Moore | Cultural responses to environmental catastrophes: post-El Niño subsistence on the prehistoric north coast of Peru[END_REF], Perrier et al. 1994) and in Pleistocene marine terrace units in southern Peru and Chile [START_REF] Ortlieb | Déséquilibres U/Th, rapports allo/isoleucine et teneurs en 18 O des mollusques de dépôts littoraux pléistocènes du sud du Pérou: une base d'appréciation chronostratigraphique[END_REF][START_REF] Ortlieb | A warm interglacial episode during oxygen isotope stage 11 in northern Chile[END_REF]. P. thaca may thus potentially provide useful palaeoceanographic and paleoclimatic data along the coast of the East Pacific Ocean, south of central Peru. However, unlike other Veneridae species, e.g. Mercenaria mercenaria [START_REF] Jones | Marking time with bivalve shells: oxygen isotopes and season of annual increment formation[END_REF], Artica islandica (Witbaard 1997[START_REF] Buick | 100 years in the dark: extreme longevity of Eocene bivalves from Antarctica[END_REF], Chione sp. (Schöne et al. 2002a), and Protothaca staminea (Takesue & van Geen 2004), P. thaca shells do not have conspicuous growth patterns. Therefore, a study of P. thaca was undertaken to determine if temporal and environmental information can be extracted from growth patterns in its shell. This study aimed to provide the sclerochronological framework for future geochemical analysis oriented towards a validation of P. thaca for paleo-El Niño reconstructions. This is the first sclerochronological analysis of the Peruvian-Chilean Protothaca thaca shell. It is based on (1) microscopic observations on thin sections and acetate peel replicates and (2) correlation between growth increment widths and water temperature recorded during growth. Our study shows that a 'summer check' (SC) is formed in the shell when SST is >18°C for > 3 wk. Under La Niña summer conditions, SCs can be absent. Finally, the widest SCs are related to the strong 1997-1998 El Niño, emphasising the potential of P. thaca shell as recorder of past ENSO events.

MATERIALS AND METHODS

Samples

Protothaca thaca is a subtidal marine bivalve (Veneridae) that lives up to an age of 7 yr in shallow water depth (maximum 20 m), just below the surface of sandy substrates (Urban 1994, Urban & Campos 1994). It has a wide distribution range (12 to 45°S) and lives in water temperatures between 5 and 26°C (Urban 1994). Urban (1994) showed that P. thaca survives El Niño events, thanks to its high lethal temperature threshold (LT50 = 27.9°C) and high tolerance to rapid temperature increases (< 50% mortality in the case of an abrupt increase by 14°C). P. thaca specimens were studied at 2 sites: Pocoma, Peru (17°25' S, 71°22' W) and El Lenguado, Chile (23°46' S, 70°28' W) (Fig. 1A).

The 4 Pocoma shells studied belong to a population for which the growth of individuals was followed from at least May 2003 to September 2003; 85 individuals were put in net-bags fixed to the bottom in situ. Once per month, the Protothaca thaca specimens were removed and immersed for 3 h in a bucket with seawater and 100 ppm of calcein; 2 specimens were taken after each marking, while the others were replaced in situ until the next marking. Then 4 specimens, 2 specimens with an initial marking from May 15, 2003 (PC77, PC134) and 2 with an initial marking from July 16, 2003 (PC50, PC127) were used for growth increment measurements. These specimens were sacrificed on 16 July 2003 (PC77), 14 August 2003 (PC50) and 21 September 2003 (PC127), (PC134). Daily SST data were obtained from the Ilo Station of the Instituto del Mar del Perú (IMARPE), which is near the Pocoma site (Fig. 1A).

Shells of dead Protothaca thaca were collected on the beach at El Lenguado in December 2000. Only specimens with articulated valves, i.e. from individuals that had died only a few days earlier, were used. From this sample, 6 specimens were randomly selected for the study of shell growth anomalies.

Sclerochronological methodology

The Protothaca thaca shell consists of 2 aragonitic layers, an inner homogeneous layer and an outer prismatic layer, where the growth increments are largest and can be more easily observed (Fig. 1B). Growth marks were identified by macroscopic observation of the shell surface, light microscopy and scanning electron microscopy (SEM). Shells were cut along their maximum growth axis using a high precision diamond saw (Isomet 5000 Buehler). The 4 Pocoma shell sections were polished and acetate peel replicates were made after etching with 10% acetic acid for 30 s. Microstructural growth units and growth anomalies were identified by combining diffused and transmitted light microscopic observations of thin sections and acetate peels, and SEM imaging (Philips 505). The width of each thinnest growth increment was measured on the acetate peel replicates of the 4 Pocoma samples under an optical microscope with a precision of 5 µm. One valve of each of the 6 El Lenguado specimens was cut as stated above and the thickness of the major growth anomalies was measured on thick polished sections with a precision of 5 µm under an optical microscope with diffused light.

RESULTS

Microgrowth increments

The thinnest clearly bounded growth increments have a width of 10 to 120 µm and are limited by a 3 to 5 µm thick line of organic matter (black in transmitted light, etch-resistant) (Fig. 1C). These microgrowth increments are thinner in the last stages of life of the individual, reflecting the growth rate decrease related to ontogeny (see Fig. 3). Increment width variations at the margin of sample PC127 showed cycles varying from 6 to 14 increments. The beginning/end of each cycle are characterized by a small groove on the surface of the shell, as reported in other bivalves (e.g. Chione cortezi: Schöne et al. 2002a); this cyclic pattern is thought to coincide with tidal cycles. As tital mode here is semidiurnal with a diurnal inequality (see Dirección de Hidrografía y Navegacíon; http://www.dhn.mil.pe), the microgrowth increments defined above can thus be interpreted as 'daily' growth increments.

Major growth anomalies (MGAs)

Growth anomalies in Protothaca thaca shells consist of an organic-rich layer associated with a depression on the surface of the shell (Fig. 1B). Relatively thin growth anomalies, 5 to 40 µm thick (Fig. 1D), which are irregularly distributed in the shell are interpreted as short non-periodic stress events like storms, predation attempts, etc. These irregular growth anomalies might also be related to spawning events, as P. thaca reproduction can occur in various months of the year [START_REF] Henríquez | Variación anual de la gónada de la almeja Protothaca thaca (Molina, 1782): análysis histológico[END_REF].

Major growth anomalies (MGAs) are characterized by organic-rich layers of 50 to 400 µm thickness and a more conspicuous groove at the surface of the shell (Figs. 1B &2). The microgrowth increment width is drastically reduced in MGAs (Fig. 3). We observed 3 MGAs (denoted A, B and C in Fig. 2) in P. thaca shells from Pocoma. The relative position of MGAs A and B in the shells depends on the age of the individual: in young individuals with an elevated growth rate (e.g. PC127; Fig. 2, top), the distance between A and B is greater than in older individuals (e.g. PC134; Fig. 2, bottom). If MGAs A and B (and, by extension, C) represent records of the same events in the Pocoma population, the age dependence of the position of A and B should be reproducible. The distances umbo-A and A-B were measured on the surface of 21 Pocoma shells and these age-dependent distances were highly correlated (R 2 = 0.94). Pocoma P. thaca of different ages have thus recorded the same events at different periods in their life. MGA C is located at the ventral margin of Shells PC77 and PC134, which can be dated precisely thanks to the staining experiment. The calcein baths were highly stressful for the specimens, and lengthwise growth ceased after the first marking. Thus, for the PC77 and PC134 samples, the end of MGA C is recorded at around 15 May 2003. The position of MGA C in PC127 and PC50 is determined by intercomparison of the shells and shell sections (Fig. 2). 0 1 / 0 9 / 9 9 0 1 / 0 1 / 0 0 0 1 / 0 5 / 0 0 0 1 / 0 1 / 0 1 0 1 / 0 5 / 0 1 0 1 / 0 9 / 0 1 0 1 / 0 1 / 0 2 0 1 / 0 5 / 0 2 0 1 / 0 9 / 0 2 0 1 / 0 1 / 0 3 0 1 / 0 5 / 0 3 To analyze which events induced the formation of MGA in the Protothaca thaca shells, microgrowth increment width variations were correlated with SST (Fig. 3); similar patterns were observed in PC77 and PC134 (not shown). MGA C occurred before mid-May 2003 (austral autumn) and < 50 increments were counted between MGA C and the date on which the specimens were sacrificed. MGA C thus corresponds to the austral summer 2002-2003. The MGA that occurred before MGA C, i.e. MGA B, is assigned to the austral summer 2001-2002. The number of 'daily' growth increments between A and B greatly exceeds the number of days in 1 year (Fig. 2). MGA A is therefore interpreted to correspond to summer 1999-2000 (Fig. 3). The overall decrease in growth rate and the decrease in the number of increments counted from summer 2000 to the date of sacrifice are in agreement with ontogenic development. The summers 1999-2000, 2001-2002 and 2002-2003 were those for which SST exceeded 18°C either almost continuously for > 3 wk (1999)(2000)(2002)(2003) or repeatedly over 3 mo (2001)(2002).When these SST conditions are not reached, no MGA is observed in the P. thaca shells (summer 2000-2001 between A and B). MGA were called 'summer check' (SC).

MGAs and El Niño

In the 6 El Lenguado specimens of Protothaca thaca collected in December 2000, 4 MGA were identified and assigned to the summers between 1996-1997 and 1999-2000. The MGA attributed to the strong 1997-1998 El Niño event was characterized in most of the shells by an alternation of normal growth (lightcoloured layers) and reduced growth (organic-rich layer), rather than by a continuous thick organic-rich layer. A total of 42 SCs measured in 13 specimens, including those from Pocoma, showed that the strong 1997-1998 El Niño event led not only to the widest SC of the population (mean width 868 µm; significantly wider than SC from other years, p < 0.001) but also to the most varied individual response (Fig. 4).

DISCUSSION

Environmental significance of MGAs

Shell growth reduction or cessation is linked not only to specific SST conditions, but rather to a combination of environmental changes, including salinity and reduced food availability. In addition to other environmental and physiological parameters, food availability is one of the most important factors that controls molluscan shell growth rate (Witbaard 1996, Sato 1997, Schöne et al. 2005). The absence of SC -showing 'normal' summer growth -may indicate not only anomalously reduced SST (La Niña period), but also favourable environmental conditions. La Niña events generally lead to an increase in primary production, as reported for the 1996-1997and 1998-1999periods (Thomas et al. 2001[START_REF] Carr | Evolution of 1996-1999 La Niña and El Niño conditions off the western coast of South America: a remote sensing perspective[END_REF]. We surmise that the La Niña 2000-2001 summer induced both lower SST (see Fig. 3) and higher productivity.

MGAs and El Niño

Several studies showed that the strong 1997-1998 El Niño event along the Peruvian-Chilean coast was characterized by the occurrence of 2 El Niño maxima (June-July 1997 and December 1997-January 1998) separated by a relaxation period [START_REF] Blanco | Seasonal climatology of hydrographic conditions in the upwelling region off northern Chile[END_REF][START_REF] Carr | Evolution of 1996-1999 La Niña and El Niño conditions off the western coast of South America: a remote sensing perspective[END_REF][START_REF] Escribano | Biological and chemical consequences of the 1997-1998 El Niño in the Chilean coastal upwelling system: a synthesis[END_REF]). During the El Niño pulses, SST, salinity and oxygenation of the water column increased [START_REF] Escribano | Biological and chemical consequences of the 1997-1998 El Niño in the Chilean coastal upwelling system: a synthesis[END_REF]). The spatial pattern and concentrations of chlorophyll closely followed those of the SST, with low values during El Niño peaks and high values during the relaxation period [START_REF] Blanco | Seasonal climatology of hydrographic conditions in the upwelling region off northern Chile[END_REF][START_REF] Carr | Evolution of 1996-1999 La Niña and El Niño conditions off the western coast of South America: a remote sensing perspective[END_REF][START_REF] Escribano | Biological and chemical consequences of the 1997-1998 El Niño in the Chilean coastal upwelling system: a synthesis[END_REF]. This succession of environmental conditions that were either potentially unfavourable (El Niño peaks with high SST and low primary production) or favourable (relaxation period with lower SST and highest productivity) during the 1997-1998 El Niño event may explain the specific microstructural pattern of the Protothaca thaca El Niño SC as well as the variable individual response observed.

CONCLUSIONS

The sclerochronological analysis of recent Peruvian-Chilean Protothaca thaca indicates that the width variations in microgrowth increments may be related to the tidal cycle. Two types of growth anomalies were evidenced. The finest growth anomalies were interpreted as temporary stress events, while MGAs were attributed to anomalous summer environmental conditions, e.g. high SST over a longer time period, and named 'summer check'. During La Niña events, reduced summer SST and enhanced primary productivity lead to the absence of SC formation. The lifespan of bivalves (i.e. the time span of environmental variations registered) established from counting of MGAs should be used with caution, particularly in fossil specimens, as the environmental conditions which determine the formation of annual growth rings must be identified for each species and environment. In specimens collected in 2000, long-lasting high SST and associated environmental changes related to the 1997-1998 El Niño event led to the widest SC. We conclude that SC widths in fossil P. thaca shells are a proxy of paleo-ENSO events.

More work is needed to define the environmental conditions that induce SC formation in Protothaca thaca shells, particularly with regard to primary production. This study provides a basis for the interpretation of P. thaca shell microstructures, an essential step towards the calibration of proxies in modern shells. Geochemical analyses of shells, which are currently under way, should provide new clues to identify and evaluate the relative importance of the different environmental parameters responsible for MGA formation in P. thaca shells.

Fig

  Fig. 1. (A) Sampling sites (stars). (B-E) Protothaca thaca. Structures and microstructures of the aragonitic shell. (B) Major growth anomalies (MGA); black triangles: surface grooves; white dotted lines: thick organic-rich layers (polished thick section, diffused light). (C) Daily growth increments. Arrows: growth rings of 1 day (acetate peel replicate, transmitted light). (D) Sporadic growth anomaly (retro-diffused electron SEM image). (E) MGA (retro-diffused electron SEM image). Scale bars for (C)-(E)= 100 µm

Fig. 2 .

 2 Fig. 2. Protothaca thaca. Identification of major growth anomalies (MGAs) in 4 shells (identification nos. given) from Pocoma (Peru). A, B and C are MGAs on valves (scale bar = 1 cm) and on thick polish sections (diffused light; scale bar = 1 mm); no. of daily growth increment between MGAs given above each section. Solid vertical lines and dates (right): end of growth. MGAs connected by dotted lines between shells

Fig. 3 .

 3 Fig. 3. Relation between recorded sea surface temperature (SST, bottom panel) and daily growth increment width variations in Protothaca thaca shells PC127 and PC50. Major growth anomalies A, B and C represented by small daily increments ('summer checks') are in black and related to the corresponding high summer SSTs. Solid lines at right: end of growth

Fig. 4 .

 4 Fig. 4. Protothaca thaca. Means, minima and maxima of 'summer check' (SC) widths in shells (mean and range; n = 42 SC). Filled squares: El Lenguado (Chile) (N = 6). Empty squares: Pocoma (Peru) (N = 7)

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Acknowledgements. This study was supported by PALE-OTROPIQUE (L'Institute de Recherche pour le Développement, IRD) and the CONCHAS project, PNEDC. We thank S. Caquineau (IRD, Bondy, France) and J.-P. Cuif (Paleontology Unit, University of Paris XI, Orsay, France) for SEM imaging. We thank S. Zevallos (Pocoma), L. El Jouhari, N. Guzmán (Ilo Station) and students (Facultad de Recursos del Mar, University of Antofagasta for the realisation and follow-up of staining experiments and SST data. We are grateful to O. Heilmayer for his constructive comments and English corrections on the manuscript. We also thank 2 anonymous referees for their critical reviews.


Didier Seyfried
email: didier.seyfried@insep.fr

Better coaching the elite swimmer with the applied use of the optimal individual stroke rate parameters

Keywords: Modelling, swimming, cadence, velocity, stroke length, feed back

A good number of mathematical relations found between the obtained speeds on clean swimming but equally on non-swim areas (starts, turns, underwater part) can be a source of potential help to the individual swimmers if they can be computed. Looking to take the spontaneous frequency of swimming to take advantage of it in an applied way of better learning (for the swimmer) and better coaching has been a method we developed from 1991 in the national sport institute of Paris (INSEP) since it appeared to be the most effective in terms of swim economy. The stroke rate/velocity relationship is very interesting since its mastering has a lot of consequences on energy cost, delay of fatigue and better learning of the best stroke at any moment in training sessions or competitions. The stroke rate/velocity test is incremental and carried though the observation of 15 meters of clean swimming where 3 full cycles are measured considering the time and the spontaneous stroke rate of the swimmer, during 8 progressive steps. These starting points guided the development of several types of software beneficial to swimming training including NATAVIT (1995NATAVIT ( -2000) ) and AQUACYCLE (since 2000) but equally a concept of measurement automated in training (CHRONOCYCLE) and at last a federal video-electronic system which is used in competition by the French Swimming Federation).

Introduction

Looking to take the spontaneous frequency of activity to take advantage of it in an applied way of better learning (for the swimmer) and better teaching (for the coach) has been a mission since 1991 [1,2]. In swimming, the spontaneous stroke rate/velocity was at first an indicator then became a systemized test from 1992 [3,4]. It is used in many countries, notably in swimming to determine if the rate and by result the distance per stroke, also called stroke length, used by a swimmer at a given moment in his swim (in training or competition) is the most effective in terms of economy as well as in other sports [5,6,7,8,9]. This starting points guided the development of several types of software beneficial to swimming training including NATAVIT [10] (1995NATAVIT [10] ( -2000) ) and AQUACYCLE (since 2000) but equally a concept of measurement automated in training (CHRONOCYCLE) and at last a federal videoelectronic system which is used in competition by the French Swimming Federation.

In France and at INSEP in particular, the choice of a kinetic study of cyclic parameters evolving within useful swim velocities was at the origin of the belief in the relation between stroke rate and velocity. This was confirmed through the development of standards for this test and through the use of tools. The applied usage in training of these tests was carried out through the use of individual test results established using tables (Microsoft Excel), then on programmable machines (from 1992 to 1996), leading the French Swimming Federation (FFN) to ask INSEP to develop a specific software NATAVIT. This software allowed from data obtained in tests at the National Training Centre, the computerized mastering of the accurate individual velocities of swims, with indications for the best cyclic, physiological and technical methods.

Methods of evaluation and follow up in training

The stroke rate/velocity test is incremental and carried though the observation of 15 meters of pure or cleans swimming where 3 full cycles are measured considering the time and the spontaneous stroke rate of the swimmer, during 8 progressive steps. It allows for every swimmer to be given theoretical cyclic parameters vs. observed ones during future sessions. Theoretical Stroke Length (TSL) vs. Observed Stroke Length (OSL), Theoretical Stroke Rates vs. Observed Stroke Rates (OSR) and even Theoretical Stroke index (TSI) vs. Observed Stroke index (OSI), all of them being good factors to take into account in terms of swimming economy during the observations of training sessions and races. The linear adjustments of the relationship of stroke rate velocity and Distance per stroke velocity all the more correlated since the level of expertise of the swimmers is high [2]. It is normal for the physical to be linked to drag as the distance per stroke diminishes in a manner inversely proportional to velocity according to a linear mathematic relationship.

Discussion

Many elite swimmers seem insufficiently educated on this approach [2]. The observation of swimmers in competition [11] indicates unnecessarily high stroke rates in comparison with their individual demonstrated ideal economy of swims for the velocity given. The confusion between « velocity and turn over » is all the more natural under the stress of competition. This is the reason it must be checked and practiced in training and at certain competitions. From exchanges with T.M. Absaliamov, the long time expert in charge of the study of the Soviet then Russian swimmers, we reinforced the fact that the pace regularity and stroke rates of Salnikov or of Sadovy, the technical management of race of Popov, had been obtained by practice and were the fruit of very elaborated feed back. In France, the number of repetitions at race velocity, while doing the report on the cyclic parameters is more and more used with the swimmers. Work at sub-maximal speed deserves equally to be given to swimmers with a reference to cyclic objectives, for example a number of arms strokes by length according to the speed of the swimmer.

Conclusion

Our evaluations show that for all the swimmers that get faster at INSEP over several years, the two values of stroke rate and race pace still evolve in the direction of an increase of the distance per stroke and of a decrease of the rate. Nevertheless, only the improvement of performance in times must remain the objective. The increase of the distance per stroke for a velocity of given swims (and therefore the proportional decrease of the rate) is only interesting if the swimmer preserves the same « potential of rate » throughout his career to attain a race pace which always improves in competition. Different methods can help optimize the management of the cyclic fitting parameters to the velocity of the corresponding swims. The example of the relationship between stroke rate and the velocity of swims seems to be the most striking. After determining the equation rate velocity MSR (modelled individual stroke rate), this one can be integrated into software or computer devices (programmable machine, software on computer or PAD) and will use the swimming economy index for the calculation of the ideal cyclic parameters for all the times for all distances and size of pool and of given send-offs. This system offers the chance to do a cyclic and technical example with the swimmer immediately after each series. Recent developments (AQUACYCLE) allow as well the possibility for the swimmer to self-evaluate simply in terms of «arm hits» : checking the clock and counting the arm strokes is enough but essential for better learning. These methods allow the swimmer to refine his mastery of spatial-mental skills, a critical step in his control of the cyclic parameters relating to his velocity of swims. These situations where objective information is given during or immediately after the stop of the exercise are essential for the formation of swimmers. This is particularly useful with the long distance swimmers where the instruction or feedback during the exercise contribute to the learning curve necessary to maintain of the stability of the energy cost [12, 13, 14, and 15]. Constant pace is a strategy that has been proven in terms of swimming economy and most notably in records surpassed; nevertheless, there are often other strategies [16] that prove themselves essential to winning at championship meets where the individual athlete is confronted with the primary objective of being on the podium. Faster start, accelerate at the right moment or know how to « touch them out » must have also been worked in training; but to start out faster does not mean a « breakthrough » in attempting to go for broke; that is taking a strategic risk, calculated in certain cases or by feel in others, with a technique of swimming able to react, in an adapted way to the immediate needs of the swimmer. The mastery of the relationship between stroke rate and velocity allows one to work towards swimming at a constant speed and therefore to a stable rhythm, to adapt with better effectiveness to all likely velocities used by the swimmer. The acquisition of biomechanical indicators by trial and error across the spectrum of velocities allowing the movement in water, with « feedback » in the fastest possible manner on execution is probably a learning curve for the elite swimmer in the years to come.


The Tour de France and the Doping Issue [START_REF]The French language distinguishes between terms for doping in sport ('le dopage', 'se doper') and words to do with drug-taking ('la drogue', 'un drogué[END_REF] Patrick MIGNON (Article paru dans : The international journal of the history of sport, june 2003, vol. 20, n 2, pp. 227-245) The Tour de France's economic and symbolic importance has turned it into a distorting mirror of how cycling works, particularly regarding doping and its treatment. There are indeed a lot of good reasons that cause one to find doping in the Tour de France because it is such a hard race that it pushes the sport of cycling -more generally -to extremes. But doping is not just taking products to enhance performance or maintain one's position. It is also a scandal or a social or health problem once these performance-enhancing practices become subject to rules, when a sport decides to ban certain products out of concern for equity between competitors, or once they become subject to the law when the State considers it must ban the consumption of certain products because they are dangerous to individuals' health or because it gives a bad image to an activity that should set a good example. The relationship of doping and the Tour de France is not simply one that links a demanding competition and the means employed by riders to face up to that. It is one where a sports event, because of its popularity, is a site where the problem will be aired in public. The Tour de France is the occasion when doping is defined and when the array of measures to deal with it will be set in train. It is therefore where the ability of sports governing bodies and political authorities to deal with it and resolve it will be judged, in dramatic fashion.

THE TOUR AS THE CYCLING EVENT PAR EXCELLENCE

The Tour de France is undoubtedly the cycling event par excellence. The race, organized nowadays by the Société du Tour de France, a subsidiary of the Amaury press group, has a budget of £18 million. It offers more than £1.5 million-worth of prizes (including £220,000 to the winner). Millions of spectators line the route each July to watch the riders and the publicity caravan of 250 vehicles representing 40 brands. Millions of television viewers spend several hours in front of their sets watching the daily broadcasts. The Tour de France is also the shop window of world cycling, the most popular and the most followed sports event because, from Albert Londres's 'convict labourers' in the 1920s through Antoine Blondin's 'giants of the road' in the 1960s, today it offers three weeks of real drama. Georges Vigarello's founding text [START_REF] Vigarello | Le Tour de France[END_REF] on the history of the race shows clearly that its introduction into the world of cycling and its inscription into the national collective memory came about not only because of its systematic exploration of the resources of the whole of the national territory, its plains and its mountains, but also because of the race's duration and length necessary to fulfil its objective of covering the national space and its range of summer climatic conditions, scorching heat and the rain and cold of climbs. Riders repeat their efforts every day, employing different types of effort, testing the body in different ways: short-lived effort to gain time in a stage; solitary efforts in time trials; falls caused by the bunching of riders in the peloton, the vagaries of the road surface, and by sudden accelerations, etcetera. The Tour de France involves a permanent mobilization of the riders, of their body and mind.

The riders reckon that a good Tour takes one year off your life, and when you finish in a bad state, they reckon three years … You can't describe to a normal person how tired you feel … In 1987, when I finished in a really bad way it took until the end of November to recover; by that I mean until I could wake up and not feel tired as if I had already done a day's work.

The fatigue starts to kick in on the Tour after ten days if you're in good shape, and after five days if you're not in your best condition physically. Then, it all just gets worse and worse, you don't sleep so much, so you don't recover as well from the day's racing, so you go into your reserves, you get more knackered, so you sleep less … It's simply a vicious circle.

The best way of describing how you feel is that it's as if you were a normal person doing a hard day's work, you've got flu, and you can just about drive home and fall into bed. By the end of the Tour, you need sleeping tablets.

You can't divide the mental and the physical suffering; you tend to let go mentally before you crack physically… Riding up one of the mountains in the Tour if you're feeling bad is like being sick. Physically, your body has a limit every day, there's only a set speed you can go at and it might not always be enough. The pain in your legs is not the kind of pain you get when you cut yourself, it's fatigue, and it's self-imposed… It takes two weeks to recover from a good Tour, three months to recover from a bad one. [START_REF] Interview | Sport, Health and Drugs: A Critical Sociological Perspective[END_REF] This account by Robert Millar, the Scottish professional, echoes all those descriptions by riders of their experience of the event. We have, here, to imagine the notion of mental strength, both the moral strength to finish the event, but also the moral qualities that a rider needs to bring to bear to live up to the expectations of organizers, media and public. This is because the accumulation of difficulties, whether unavoidable, like the necessary transfers from one place to the next, or deliberately calculated, in order to make the event more spectacular, produce the heroic nature necessary to the popularity of the Tour. And its more or less instantaneous commercial success has long been an attraction to champions, thus structuring competition between riders and generating increasing challenges and exploits. It is a confrontation with other competitors, but also with the public who expect riders to show the moral qualities of effort, hard work and solidarity, but also those of unselfishness and 'class'. Moreover, as an object of media coverage from its beginnings, the Tour de France cannot avoid seeing an increase in the demands on competitors with the ever-growing importance of television, whose systematic coverage of every stage has also brought in, on top of the necessary battle for the stage win, the necessary battle for permanent presence in front of the TV cameras, therefore making races ever faster.

A HISTORY OF DOPING IN THE TOUR DE FRANCE

The long-standing presence of doping in the Tour brings us back to the excessive nature of the race. Cycling was one of the first professional sports and the exploits of track racers, notably competitors in the Six Day events, and of the first competitors in the early 'classics', excited the interest of journalists curious to know how they could manage these exhausting events and wanting to understand their mysterious entourage of soigneurs, masseurs and miracle-worker doctors.

There are good reasons to believe that competitors in the early Tours used what track-racers used. The confessions of the Pélissier brothers to the great investigative journalist Albert Londres (see also Chapter 4 above) may be considered as the first doping affaire. The scene took place on the evening of a Tour stage in Coutances on 27 June 1924: 'You have no idea what the Tour de France is like,' said Henri. 'It's a Calvary. But Christ had only 14 stations of the cross. We have 15. We suffer from start to finish. Do you want to see what we run on? Look.' From his bag he took out a phial: 'That's cocaine for the eyes, that's chloroform for the gums.' 'That,' said Ville, also emptying his musette, 'is a cream to warm up my knees.' 'And the pills, do you want to see the pills? Look, here are the pills.' They each took out three boxes. 'In short,' said Francis, 'we run on "dynamite".' This scene, which has been replayed hundreds of times since, was first recounted in Le Petit Parisien. It is the scene that popularized the image of 'the convict-labourers of the road', of the Tour de France riders seen as workers who have to use whatever is in their power to complete their task. But is it a doping issue? Probably not, since the point was not, either for the journalist or for the riders, to denounce an illicit practice, but to show how cycle racers were exploited by organizers who not only impose on them terrible workloads, but who also make the racers submit to harassing controls over their clothes and their attitude during the race. The Pélissier brothers were in fact making revelations about their working conditions and about Henri Desgrange's authoritarianism. But this example also has the virtue of relating the issue of doping to that of the respect afforded to the riders: going through cases looking for doping products or monitoring modes of dress come from the same spirit of wanting to control everything and are always bound to be received with hostility as an intrusion. This points us in the direction of understanding a difficulty in anti-doping policies, which, to the world of cycling, look like constraints on workers' freedoms.

Other incidents followed, more explicitly linked to the doping issue. First, in 1955, Jean Malléjac, a good Tour rider, fainted during the climb of the Mont Ventoux. There were fears for his life and the rider only came to some 15 minutes later. He was delirious in the ambulance. Other wellknown riders like Ferdi Kubler or Charly Gaul fell victim to huge weaknesses in the same stage. The new Tour doctor, Dr Dumas, encouraged the organizers to make an official complaint; cases of riders and soigneurs were searched, and one of the latter was excluded from the race.

But the most dramatic incident was of course the death of Tom Simpson on 13 July 1967, when he collapsed on the slopes of the Mont Ventoux. Despite the efforts of Dr Dumas, still Tour doctor and an activist in the fight against doping, Simpson could not be saved. The Tour doctor refused permission for burial and the autopsy was to reveal traces of amphetamines that, while no doubt not the direct cause of the British rider's death, nevertheless led him to go beyond his limits. What interpretation can be put on these cases? They have been seen as accidents by numerous followers of the Tour, whereas other close observers have interpreted them as the most dramatic examples of common practices.

A study by Dr de Mondenard reported in Le Nouvel Observateur and Le Monde has presented elements that allow us to judge the scale of the problem. [START_REF] De Mondenard | Dopage: l'imposture des performances[END_REF] First of all he recalls the list of riders who have tested positive since 1966, the first year anti-doping tests were carried out in the Tour de France. Among them were former or future winners, such as Zoetemelk, who tested positive in 1977 and won the Tour in 1980, Gimondi, winner in 1965, who tested positive in 1975, and more recently Delgado, winner in 1988, who tested positive the same year on the thirteenth stage, but who was in the end declared winner on procedural grounds and after political pressures. On the list too were recognized top racers, stage winners or winners of the points classification, such as Pollentier, Altig, Guimard and Bellone. In particular, on the basis of a study of 667 former competitors in the Tour de France, Mondenard upheld the thesis that riders have a higher mortality rate than average, especially those whose career came after 1961, whom he called 'modern' riders.

Thus he showed that the longevity of 'modern' riders is lower than 'old' riders: 85 per cent were still alive at 60, compared to 93 per cent of their predecessors. He cited the early deaths of Rivière, Coppi, Nencini, Bobet, Anquetil and Oosterboch, from cancer or cardio-vascular illnesses, but also the fatal road accidents of Robic and Koblet, and the suicide of Luis Ocaña, which he argues may be understood as effects of psychological disturbances, such as less good perception of risks while driving, or, in the case of Luis Ocaña, as a solution to suffering caused by the consequences of absorption of doping products. He could also have referred, in the same vein, to the mental troubles of riders such as Freddy Maertens or Henk Lubberding and the difficulties they had reintegrating into society at the end of their careers. One may also recall how the Dutch PDM team dropped out of the 1991 Tour de France when their riders were supposed to have fallen victim to food poisoning. Starting from the comments of Jacques Anquetil, who justified his own consumption of doping substances as necessary in order to do his job, without ever having tested positive during a Tour, many others have come under suspicion, from Laurent Fignon and Stephen Roche to Bjarne Riis; the Italian Marco Pantani celebrated victory in 1998, but was excluded from the Giro, the Tour of Italy, in 1999 with a redbloodcell count of more than 50 per cent. The same year the American, Lance Armstrong, won the Tour, but the victory of a champion who had suffered from cancer in 1996 was bound to raise suspicions. In 2000, the American repeated his success, while the Frenchman Richard Virenque admitted taking drugs during the Festina trial. The greatest cycle race in the world is an event where victory is increasingly accompanied by doubts over the conditions under which it has been achieved.

THE TRANSFORMATIONS OF DOPING

A history of its products and mode of organization of the Tour de France can stand in parallel with this chronicle of cases of doping. The different authors [START_REF] Waddington | Health and Drugs; de Mondenard[END_REF] previously mentioned agree on how doping products have evolved and how they have been extended to different sports. At all events, cycling was one of the first involved. There was the period of consumption of stimulants and pain-killers during the first century of the history of sport from 1850 to the 1960s. These products have not disappeared and are present in the form of anti-asthmatic treatments, for example, which are over-consumed by riders, but taking over from them we find cortisones and especially EPO (erythropoietin) in the 1990s.

The introduction of this product leads us to pull on the thread of the history of the organization of doping. It is tempting to contrast two periods in the history of doping in sport. The first relates to the 'homemade' stage where doping is the equivalent of kitchen recipes that are transmitted from rider to rider, and from soigneur to rider, a period of experimentation rather than setting up systematic programmes. In a period when rules were vague concerning doping, that is up to the 1960s, this kind of doping did not necessarily appear as a problem for competitors or sports organizations: it may be imagined that everybody saw themselves on an equal footing with each other. The second period corresponds to a more rational stage -the model being the systematic doping practised in East Germany or in the USSR: within the framework of a sports programme, the latest advancements of science were applied to the preparation of sportsmen and women. Doctors became involved in sport at an early stage, but initially from a health perspective or because champions were seen as marvels who should be studied and who did not need to be improved. The reversal of curiosity towards applied research came about more or less everywhere in the 1960s. The problematizing of doping may be seen as part of the long process of civilization of behaviour that manifested itself in the medicalization of western societies. [START_REF] Waddington | [END_REF] Health values underpin the medicalization of society and encourage doping along the lines of the equation: a problem = a product. One of the consequences of this change was of course the medicalization of sport, where the sports doctor tended to act as an agent for a club or a team. The doctor therefore became part of a rationale of rapid recovery and of support for the performance potential of the sports entity for which he was acting.

Sports medicine of the 1960s saw the emergence of a new type of individual, 'the trained athlete', different psychologically and physiologically from the man in the street. There also developed medical routines specific to the sports person, with specific treatments for specific injuries, but also specific care for preparation. This went hand in hand with the development of medical staff as a necessary condition of sports preparation: bio-mechanics for exercises and massages; nutritional scientists for vitamins and complements; psychologists for personal discipline and meditation; pharmacologists for the use of different medicines available on the market. This rationale could also come to encompass non-medical uses of medicines such as steroids, analgesics, stimulants or tranquillisers. Good reasons for taking drugs are therefore contained in the properties of different products that can be listed according to their relationship to competition, but also to the organization of training. Cyclists did what everyone else did, they sought shortcuts to manage the different difficulties of a life in sport.

In cycling this type of organization appears to have developed in the 1980s, and the Tour de France, because of its physical demands and its rules (anti-doping tests), no doubt became especially affected by this. The current sophistication of doping (the complexity of programmes, of the doping calendar in relation to detection, the value of the newest molecule in a world where the difference between winning and losing is minuscule) gives weight to the hypothesis of a constant coming together of innovators and entrepreneurs from the worlds of sport and medicine. This is the case of Dr Ferrari and Dr Belloc who we come across in all the doping affairs concerning Italian cycling teams or in the entourage of various champions.

The problem that is no doubt specific to cycling is the coexistence/competition between doctors and self-appointed specialists like 'Dr' Sainz and more generally soigneurs who have come up through the ranks as shown by the table of 'qualifications' of cycling soigneurs implicated in doping affaires (from the former cyclist to the driver, and from the shopkeeper to the pharmacy assistant). [START_REF]See de Mondenard[END_REF] For Waddington 8 contemporary doping may be seen as the meeting between two rationales, the development of sports medicine and demand from athletes through the innovative or entrepreneurial elements from both worlds. That is what happened, notably, in some Italian cycling teams from the end of the 1980s: it was no longer individuals resorting to 'tricks of the trade', but companies getting organized in order to dominate collectively. Thus, in 1998, Willy Voet, the Festina team's soigneur, was intercepted by the French Customs and found to be in possession of 500 doses of doping products, including EPO and growth hormones. This was the start of the Festina affaire. Bruno Roussel, the team's sporting director, admitted that his riders were taking drugs under medical supervision that he had personally organized, and he presented himself as the organizer of a system of a rational use of doping, claiming in this way to be following a strategy of risk reduction. [START_REF]on the affaire Festina[END_REF] The team was thereupon excluded from the Tour by the director of the Société du Tour de France, Jean-Marie Leblanc, and the rooms occupied by the Dutch team TVM were searched by the police, which led to its withdrawal from the event, along with the Spanish teams who abandoned out of solidarity. The trial and the enquiries brought to light the system that, it is thought, is the one adopted by cycling teams in general. The Festina affaire, in the 1998 Tour, has taken on the status of inaugural moment of what appears to be a new attitude towards doping.

THE TOUR BECOMES AN AFFAIRE

Having appeared as a witness in the affair on 30 October 2000, Hein Verbruggen, President of the UCI (International Cycling Union), declared on leaving the court that his 'conscience was clear'. But how can he justify the fact that, while he knew about the circulation of EPO in the peloton as early as 1990, he did not encourage testing for it until 1995? And the fact that, for five years, the sums of money allocated by the UCI to anti-doping measures were only raised to 1.8 million francs [£180,000] out of a budget, over the same period, of 250 million francs [£25 million]? The discredit that fell on the ICU President stained the whole of cycling. On 9 December 2000, Daniel Baal, President of the French Cycling Federation, announced he would not be standing for reelection, officially for reasons of 'unavailability'. His retirement, as someone who had made the fight against doping his priority, was certainly not good news for the sport of cycling. [START_REF]Le cyclisme' in Encyclopedia Universalis[END_REF] The above may be read as a summary of the Festina affaire, posing the question of the delays by the sports governing bodies in implementing a real fight against doping and, in a country like France, of the part played by the State in this issue.

Despite the commotion caused by various revelations such as those cited above by Albert Londres on the 1924 Tour de France, notwithstanding the efforts of Dr Dumas, who had treated Malléjac in the 1955 Tour, the impression may be formed that nothing happened before the 1998 Tour. How can this periodization be explained? No doubt because the problems posed by the struggle against doping, which have yet to be overcome, reflect the relations between the different levels of the organization of sport: its international nature and at the same time the existence of national sovereignties; the conflictual relations between international federations and the IOC (International Olympic Committee); the demands for independence by the different national federations, not to mention the reticence of the sporting world to talk openly and publicly about its internal difficulties. There are similarly different levels at which we see expressed rivalries over control of sports policy between states wishing to intervene and the world of sport. There are also those conflicts that inevitably occur between internal sports governance and civil justice. In this way the three themes that define anti-doping policy are all areas of conflict: the list of prohibited substances and practices (there is no agreement between the sports governing bodies, the federations); the principles of testing (who carries out the tests? what means do laboratories have at their disposal? what are the officially agreed procedures?); the regime of sanctions, their nature, their duration and who carries the blame (the athletes, the federations, or the suppliers?).

In fact, a law was passed by the French parliament in 1965 that may be seen as the result of the earliest organized struggle against doping. Indeed, after his first experience of the effects of doping on a cyclist, the Tour doctor had shared his ideas with the French Medical Association for Physical Education and Sport. He recommended that the federations as a whole explicitly condemn doping, that they each appoint a doctor to their governing body, that they require their coaches and trainers to follow medical, pharmaceutical and dietary training courses, and that they educate their athletes about the dangers of doping. The L'Equipe journalist reporting these comments concluded: 'Let us hope that, now the impetus has been given, the struggle against this scourge will be pursued in an increasingly concrete fashion.' [START_REF][END_REF] For at the same time as medicalization supports the search for a product corresponding to a given problem or allows the emergence of performance medicine, it also allows the questioning of practices that would not be healthy or ethical, such as doping, which can then be denounced. Whether this double movement is seen as an effect of the contradictions inherent in medicine or as a strategy to assert authority over a given field of activity, a change did happen in the 1960s when the world of medicine began to criticize doping.

Sports governing bodies did begin to express their concerns about doping, for example on the occasion of the Rome Olympics in 1960. Sports medicine conferences were devoted to doping, and in particular there was a European colloquium held at Uriage (Isère) in January 1963, on the initiative of the same Dr Dumas, where the first definition of 'le doping' was proposed (the English term was still used in France at the time): 'doping is defined as the use of substances or of all means designed to artificially enhance performance, in preparation for or on the occasion of competition, and which can prejudice sports ethics and the physical and mental integrity of the athlete'. At this time, early in the 1960s, the Council of Europe also proposed a definition that it hoped would be valid for all European countries. The IOC voted a resolution against doping in 1962 and set up a Medical Committee in 1967 to develop a strategy against doping, and notably to establish a regularly updated list of banned products. Similarly, in 1967 the UCI established its own list of banned products and set up monitoring mechanisms, which was followed by different national federations. But already part of the problem had become visible: the federations' list and that of the IOC can differ, thus opening the way to procedural battles. In this way, when in 1988 the Spaniard Pedro Delgado tested positive for probenecide (a masking agent for anabolic steroids) his victory in the Tour de France was not challenged because the product, while banned by the IOC, was not yet on the UCI's banned list.

One of the results of this regulatory activity was the adoption in France of its first anti-doping law, called the loi Herzog, [START_REF]name of the Minister proposing the bill to parliament[END_REF] in 1965. The implementation of a national sports policy after the failure of French athletes in the Rome Olympics of 1960 and the rising suspicions concerning doping among athletes from the sporting superpowers, are sports-related reasons that may explain why doping was highlighted in France at this time and led to the 1965 law. In addition to concerns that France had to compete on equal terms with Eastern bloc countries, there was the health side of the issue which came along with the extension of the Welfare State, worries about the scourges affecting (or which might affect) young people, worries that could win general support, just as did the idea that sport was a fundamental educational tool, or indeed the action of doctors asserting their position within sport. [START_REF] Lhomme | Comment le dopage devint l'affaire des seuls sportifs[END_REF] However, this law was never really applied. Why not? Promoted in the name of defending sporting ethics, the content of the law was based on the defence of athletes' health. It set out criminal penalties for anyone, during a sports competition, knowingly using substances that artificially increase their physical capacities and endanger their health. For sportsmen and women the penalties were fines; for those supplying or encouraging doping, the penalty was imprisonment. To these criminal penalties could be added sporting sanctions such as bans from taking part in or organizing competitions. But the frontier between sports authorities and police authorities was not clearly defined. Penalizing cheating, that is measuring the damage done to sporting ethics, should be up to the different federations. Matter relating to health or trafficking should be the responsibility of the State. The 1965 law gave the State the power to punish, no doubt because it was felt that the process needed to be kick-started, but the judges did not appear well placed to judge offences that were too specific: why condemn sports people for consuming products that were quite legal elsewhere? One of the most spectacular difficulties of applying the law concerned appeals to civil courts against decisions made by sports bodies. The latter lost highly publicized cases where athletes condemned for doping obtained decisions from civil courts finding federations at fault on procedural technicalities, or guilty of infringements of personal freedoms or of employment law, or by throwing scientific doubt on the term doping being applied to their case. Thus, when the Public Prosecutor asked the presiding judge in the Lille magistrates court in November 2000 to drop the case against Richard Virenque in the Festina affaire, he felt that Virenque as a citizen had done nothing wrong as regards French law, whereas Virenque the rider had just come round to admitting that he had been taking doping products, that he had cheated in practising his sport, having declared, like others before him, that he had been 'doped unbeknownst to his wishes'. [START_REF]Virenque's tortuous phrase in French was that he had been 'dopé à l'insu de mon plein gré[END_REF] So the Buffet law of 1999 did not change the situation very much, even though, if we look at it from the rationale of the balance between prevention and repression, it has considerably developed the health axis (creation of medical centres, regular monitoring over time) and has created, in the form of a Conseil de Prévention et de la Lutte contre le Dopage (Council for the Prevention and Fight against Doping), an independent administrative authority to centralize all data concerning doping, which can also make recommendations to sports federations or indeed require them to take measures. Indeed, knowing how the Festina affaire was triggered during the 1998 Tour (the actions of Customs and police seizing doping substances and the charges that followed), [START_REF] Lhomme | For details see[END_REF] it would seem that the way to make everyone face up to their responsibilities was by a coup de force and the creation of an affaire obliging people to break the law of silence. The arrival of a new Minister for Youth and Sport, Marie-George Buffet, less sensitive than other Sports Ministers to the priority given to elite sport, no doubt for ideological reasons (she is a member of the Communist Party), and hardly minded to do favours for the Amaury Group as organizer of the Tour de France because of conflicts between this press group and the publishing union and the Communist Party, allowed these unceremonious, strong-arm tactics and the triggering of the affaire.

WHY TURN THE TOUR INTO AN AFFAIRE?

So, whereas doping was not a new phenomenon in cycling, the law of omertà governing the peloton was lifted only through the intervention of the police and the courts. One of sport's challenges is indeed to be able to control doping and all forms of deviance that comes from unreflecting socialization into the values of sport and competition. But the problem posed is precisely that of sport's ability to enforce respect of its own rules. For, if sport has gradually won its own autonomy and the freedom to run its affairs in its own way free from outside interference, nearly two centuries later the issue is less about guaranteeing its autonomy against its opponents, but preventing its uncontrolled and limitless development.

The reason is that sports authorities have too much difficulty in protecting the monopoly of legitimately defining sport when, firstly, professionalism and, secondly, media involvement are bringing in new stakes (for sports people, earning their living) or new definitions (from the public of cognoscenti to the general public who want entertainment and spectacle). In sport today, the power to give awards or distribute sanctions is moving away from the federations and going to events organizers and the courts, and the various protagonists are seeking to assert their own interests: players and athletes are seeking glory and are pursuing their own financial interests; medical companies want to offer more and more treatment; journalists want news and want to create events; judicial authorities want to enforce respect for the law, and so on.

The Festina trial has shown that sports organizations have long facilitated doping practices, across the board, as, earlier, did the Dubin Report on Ben Johnson or the Delgado affair when the decision not to exclude the Spanish rider was taken under joint pressure from the President of the UCI, Mr Puig, and the Spanish government. [START_REF] Paul | Systèmes des sports[END_REF] Some people stress rising economic and commercial stakes to explain the difficulties of combating doping: but it is just as much in the interests of the UCI and the Société du Tour de France to develop an anti-doping policy, to defend sporting ethics and to avoid losing sponsorship, as to cover up cases of doping for the same reasons. [START_REF] Simson | on the IOC, in The Lords of the Rings: Power, Money and Drugs in the Modern Olympics[END_REF] For Georges Vigarello, [START_REF] Vigarello | Le sport dopé[END_REF] it is sport's claim to make itself into a virtuous 'alternative society' that is preventing it from recognizing the problem. This alternative society of sport defines its purity by setting up boundaries: in the past, it was professionalism and money, today it is doping. However, this frontier is difficult to draw, because the criteria that allow doping to be defined are eminently debatable: take, for example, the definition of doping as recourse to artificial means to gain an unfair advantage -what is that worth when the whole of sport is based on the exploitation of increasingly sophisticated technology? How can it be recognized that doping may be a consequence of competitive sport when sport is defined as a virtuous world par excellence? Hence, the fact that you can only run 'trials for witchcraft' and that it is impossible to get the 'guilty' to admit their guilt. However, morality -right and wrong -is not enough to combat the problem, as doping is a health issue, since doping has been medicalized, and it is a public health issue, because the phenomenon has gone wider than elite sport. And it is a criminal issue because of the existence of large-scale organized trafficking. Public intervention is therefore necessary since health and the resources that need to be devoted to it are at stake, and because the independence of the regulator, the sports federations, is not guaranteed.

The present context is one of a crisis of legitimacy of sporting institutions, marked by the move from a unified sporting ethic to a pluralization of norms defining what is a sports person's identity and what is legitimate behaviour. Doping is one example of this. Sport is under suspicion because of the limits of dope testing or the limits of surveys and research that find it hard to quantify and describe the phenomenon. This situation is producing a theatrical model of doping affairs [START_REF] Duret | Juger les pratiques sportives[END_REF] in which the people carrying out the study (usually journalists) hunt for evidence to interest the public, while the accused seek to save their sporting reputations. Signs are looked for, such as gaining a few pounds, physical changes, links between sports people and people of dubious reputation, unexplained performances. In the meantime, the guilty, according to the degree of guilt admitted, deploy defensive strategies that deflect the accusations onto others (they deny it and cast doubt on others and their doubtful performances or on their envy or jealousy), they present themselves as persecuted, push the accusation onto a third party (a dishonest trainer), play down the seriousness of the phenomenon ('everybody does it'), turn the stigma round into a sacrifice they willingly accept as the price of the grandeur of the sport, or, finally, convert to the moral struggle against doping. Other writers [START_REF] Duret | Le sport et les affaires. Une sociologie de la justice de l'épreuve sportive[END_REF] have identified further ways of legitimizing attitudes in defence of doping or a desire not to bring out doping affairs into public view: the defence of a total engagement with sport, loyalty to the family of sport, the defence of transparency and truth, virile conduct able to resist pressure from the press or the police, and respect for one's employer. This explains why Virenque, like Anquetil before him, remains a hero.

A SUB-CULTURE

The first dope-tests were carried out in 1966 and they triggered a riders' strike, just as in 1998 the searches triggered protests. Jacques Anquetil, in a series of interviews in 1967, 21 declared that 'the anti-doping law is idiotic', adding: 'Yes, I have taken doping products.' Similarly, two years before his death, Tom Simpson had said in The People that he used doping in order to do his job. And as a defence of Richard Virenque and the other cyclists in the Festina affaire, the question is asked how they can do their job without resorting to doping. Doping has long been seen as legitimate among cyclists, because of the nature of the job and the thin line between treatment and doping. The development of doping can therefore be analysed in relation to a physically demanding sport like cycling, [START_REF] Brissonneau | A chaque sport sa formule magique[END_REF] which is also a sport that has been professional for a long time. It has therefore become familiar with competition on the labour market, the volume of work involved (as we have seen), and the system of constraints that surround the cyclist (staying in the peloton in order to build a career and accepting the rules of the world of cycle [START_REF] Calvet | Le Mythe des géants de la route[END_REF] The meeting of innovators and entrepreneurs was made possible by the increase in competition, which produced the emergence of specialists and professionals devoting their time to sporting activity and its preparation. The possibility of generalised competition, of professionalism (meaning paid work) and the rise in various economic stakes, produced a system of increasingly high rewards for winners or appearance bonuses for wellknown riders, in addition to income from sponsorship and television. All this created more and more reasons for not wanting to come second. Doping appeared as a means of overcoming the pain that a professional needed to endure to win. It was therefore another performance material that allowed the rider to cope with the pressures and demands produced by the internal logic of performance. It was also an aspect of the new culture of sensation, based on the general acceptance of the idea of the unlimited possibilities of an infinitely malleable body. The body came to be seen as a tool of the trade, and suffering, a part of the physical experience of the cyclist who rides for a living. Thus doping, or treatment, appeared a legitimate means to do it as well as possible for as long as possible. The Tour de France racer was a worker managing the length of his career, the intensity of his work, his injuries and his stress, using the means at his disposal.

In this framework, riders who use doping are not bad or corrupt elements, but are individuals exposed to the contradiction between the requirements imposed on them and the use of illicit means to achieve them. The sportsman using doping belongs to the category of innovative deviant who accepts the general aims but rejects the legal means in favour of illegal means. But he is not alone since this behaviour is learned, through interaction with other people from whom rudimentary or sophisticated techniques are discovered, and where riders become skilled at rationalizing their behaviour in the face of judgements from the outside. Thus, doping is the result of co-operation not only between cyclists but also doctors and trainers, and has produced a cycling subculture in which recourse to different types of 'treatments' is legitimate. [START_REF]See texts on the sociology of deviance and its application to sport, for example, Jay Coakley, 'Deviance in Sports: Is it out of Control?[END_REF] This sub-culture is formed in the interplay between internal constraints, that is internalizing sporting norms, and external constraints, in other words the action of organizations to enforce respect of the rules. And it is the weakness of these external constraints (tolerance of doping and/or lack of credibility of the tests and sanctions) that can explain the greater development of doping in cycling than elsewhere, along with the difficulty society has had in recognizing doping and its quasi-legitimation through the place occupied by medicine and the emergence of sports medicine. These two factors come together to confuse the line between treatment and doping. These are modes of legitimization of doping in so far as they give the possibility of rationalizing its use by the manner of winning, by the service given to the team or the nation. Furthermore, with the increasing condemnation of doping, this social group has to defend itself against people from the outside who do not know the rules of the game, and has to be able to keep the secret, since outsiders do not know how hard a rider has to work just to stay in the race.

Cyclists know that riding a Tour de France is not good for their health; they know too that opponents use doping products, and they also know that so do people who do not take part in sports competitions. They think that the constant marketing of new substances for performance or treatment (whether Viagra or Prozac or any other medicine) makes using these substances normal. These automatic reactions, and the feeling of being individuals outside the mainstream, allow them to think that the desire to play the game, to stay in the peloton, is stronger than the desire to win and make money. Even those who have no chance of winning the Tour want to stay in the game and respect the norms of the performance ethic and of the peloton. This desire supports the law of silence that protects the group against accusations from the outside and makes it reject people who, like Gilles Delion or Christophe Basson, want to promote the idea of dope-free cycling: Basson was driven to drop out of the 1999 Tour. The law of silence is reinforced and protected by the incredulity of admiring spectators who reject accusations of doping like any other accusation that highlights riders' deviance.

THE TOUR DE FRANCE IN POPULAR CULTURE

The public believes, so we learn from opinion polls, that cycling is the sport most affected by doping, but it is estimated that a third of people understand and accept this phenomenon. In spite of the revelations and the dramas, the public remains loyal, on the roads and in front of the TV screens. Is the public a victim of the media? Do they refuse to believe because they want to be entertained? Perhaps there exists a strong link between cycling culture and popular culture. Cycling, as one of the most popular sports in France, is a model of individual advancement, at the same time as it offers a reading of how to achieve this advancement. When you are small, when you come from the bottom of society, you understand cheating, just as you admire the physical courage or the grace of an Anquetil surpassing himself at critical moments.

Faced with the uncertainty of definitions, members of the public balance their attitude in the same way as sports philosophers. Why should doping be banned or combated? Because there is a counterpart of sports justice and the breaking of the rules of fair play: the doped rider is giving himself an unfair advantage in a world based on the principle of organizing fair competition. Also, resorting to doping is expensive and so can bring in a difference between those who can afford the products and those who can't. The latter are also likely to be the ones who would not be able to benefit from medical help to control the effects of the product. This point opens up a series of arguments about doping damaging the health of those taking it in so far as the dangers of these products are too well known or, conversely, their precise effects on the body are not known.

Recourse to doping products thus implicates the integrity of anyone who ingests foreign substances into his own body that will make his body function beyond its natural aptitudes: doping is therefore the artifice that goes against the principle of using natural abilities. As an attack on the physical integrity of the individual, it is also morally reprehensible because it seems a form of coercion: the athlete who wishes to remain faithful to sporting ethics, but who wants to regain the equality he has lost, has a different set of rules imposed upon him by those who use doping, without taking into account that coercion can also be exercised by members of his entourage. Furthermore, doping, since it is seen as cheating, damages the image of the sports player and of sport in general as a model for the education of young people or as a means of integration that can be held up as a model. However, these arguments come under criticism when the boundary between drugs and doping is questioned: one might ask in what way is cannabis a doping product? Or, regarding the boundary between doping and treatment, why is Ventolin, a medical treatment for asthma, banned for sports people? Additionally, it might easily be thought that doping is not just about improvement of performance, but it could also be about restoring the sports person's health. Furthermore, pointing the finger at doping as a danger to health is challenged because of the lack of knowledge of the real effects of products, and, indeed, if the issue was about damaging sports people's health, then elite sport as a whole would have to be questioned. And it is looking at elite sport that highlights the debatable arguments of the defenders of natural sport or fair sport. Indeed, elite sport is based on all sorts of artificial aids to enhance performance or improve the comfort of athletes: fibreglass poles, track surfaces, dérailleur gears and training. So why exclude the artificial aid of doping? All the more so because there are techniques considered as doping which are based on the use of natural products such as testosterone, or blood transfusion techniques, including transfusions of an athlete's own blood. In fact, condemning doping as an artificial aid is, in the end, challenging a fundamental principle of sport, one which attaches it to modernity, namely its relation to the idea of human progress. And what becomes clear when thinking this way, and what we know to be true, is that cycling, especially the Tour de France, is the hardest of sports.