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International audience; Introduction. People with reduced physical fitness (PF) are at greater risks of reduced health-related outcomes [1]. In response to COVID-19 global pandemic, French government has imposed lockdown on March 2020 for 8 weeks. A decreased physical activity (PA) levels in several countries and different populations were observed [2-3], which could in turn reduce both PF and health-related outcomes. Increases in the body mass index (BMI) and decreases in several PF outcomes were observed in adolescents after COVID-19 lockdown, compared to the pre-pandemic period [4]. However, less data are available in the adult population. The aim of this study was to assess PF in adults during the first French lockdown.Methods.Adults (age >18 years) never been tested positive for COVID-19 took part in an online survey including sociodemographic outcomes (sex, age, BMI, socio-professional categories (SPC), education status, daily physical activity, sedentary behaviors, familial environment and four self-administered PF tests (one-minute sit-to stand test: STS; unipodal tests: UP left & right; chair test: CT). Measures were carried out at three weeks in lockdown (P1), at the end of lockdown (P2) and one-month after lockdown (P3). Participants were grouped based on their previous (before lockdown) lifestyles (four profiles regarding sedentary behaviour (SB) and PA levels : sedentary is ≥ 7h/d of sedentary behaviors and active is ≥ 150 min/d of at least moderate physical activity [5]). Linear mixed effects models were fitted to analyze the differences in PF tests at the three lockdown times periods and the influence of the sociodemographic parameters.Results. A total of 104 participants (32 men and 72 women) completed tests of PF (age, 44.3±15.8 years; BMI, 22.8±3.3 kg/m²; 12% lived alone, 34% had children; 28% were active and 56% were sedentary; 17% were retired). Sixty percent had a professional activity during lockdown, 80% of them working as executives, employees or retired, and 56% had at least a master's degree. No differences were observed at P1 between the SB and PA subgroups for the four tests. However, the non-sedentary sub-groups present higher PF performances. PF performances for the non-sedentary subgroups increased from P1 to P2 and from P1 to P3 (p

Notre étude présente deux objectifs principaux. Le premier objectif est d'évaluer les réponsesmétaboliques chez des triathlètes entraînés lors d'un enchaînement cyclisme – course à pied au coursduquel l'épreuve de cyclisme est réalisée, soit à puissance constante, soit à puissance variable. Ledeuxième objectif de cette expérimentation est d'analyser l'influence de ces conditions de pédalagesur la performance lors de l'épreuve de 5 km de course à pied.. Dans cette perspective, 8 triathlètesde bon niveau de pratique et habitués aux situations d’enchaînement cyclisme-Course à pied, ontparticipé à cette étude. L’épreuve de 20 km de cyclisme était réalisée soit à allure libre, soit àallure constante, soit avec des variations d’intensité. Les 5 km de course à pied qui suivaientchacune des situations de cyclisme, étaient réalisées sans consignes fixes, où le seul but était larecherche de performance sur cette distance et pour l’ensemble des conditions de terrain. Lesrésultats montrent une performance en course à pied d’autant plus performante que le cyclismea été réalisé à allure constante. En l’absence de différence significative sur les paramètrescardiorespiratoires, l’hypothèse avancée est une fatigue musculaire plus importante engendréepar les variations d’intensité en cyclisme.Ces résultats soulignent que la stratégie, le niveau d’expertise des sujets, l’intensité et ladurée du cyclisme sont des facteurs influençant la performance lors de la course à pied subséquente.Des travaux ultérieurs intégrant l’épreuve de natation permettraient d’étendre toutes ces conclusionsà l’épreuve de triathlon dans son ensemble.

International audience; Objectives: To investigate the effect of three cycling cadences on a subsequent 3000 m track running performance in well trained triathletes.Methods: Nine triathletes completed a maximal cycling test, three cycle-run succession sessions (20 minutes of cycling + a 3000 m run) in random order, and one isolated run (3000 m). During the cycling bout of the cycle-run sessions, subjects had to maintain for 20 minutes one of the three cycling cadences corresponding to 60, 80, and 100 rpm. The metabolic intensity during these cycling bouts corresponded approximately to the cycling competition intensity of our subjects during a sprint triathlon (> 80% V̇O2max).Results: A significant effect of the prior cycling exercise was found on middle distance running performance without any cadence effect (625.7 (40.1), 630.0 (44.8), 637.7 (57.9), and 583.0 (28.3) seconds for the 60 rpm run, 80 rpm run, 100 rpm run, and isolated run respectively). However, during the first 500 m of the run, stride rate and running velocity were significantly higher after cycling at 80 or 100 rpm than at 60 rpm (p

International audience; Purpose. – Investigate the influence of previous swimming on energy expenditure during the subsequent cycling exercise of a triathlon.Methods. – Ten well trained triathletes underwent 3 swim-to-cycle transitions and 1 isolated cycling trial (C trial). The cycling exercises consisted in 15 min on a bicycle ergometer at a power output corresponding to the ventilatory threshold +5 %. During the transitions, this exercise was preceded by swimming bouts soliciting different muscles, undertaken at a 750 m competition pace for the same duration (swimming with arms and legs: Sal trial, with arms only: SA trial, or with legs only: SL trial).Résultats. – The swimming bouts of SA and Sal trials involved a significant increase in energy expenditure during subsequent cycling in comparison with isolated cycling (P < 0.05). Moreover, cycling efficiency was not significantly different between SA and SAL trials (P > 0.05).Conclusion. – A short intense swimming leads to an increase in energy expenditure during subsequent cycling, because of the thermoregulatory adjustments and the additional oxygen cost of respiratory work involved during swimming. It also shows that physiological adaptation during cycling does not depend on the lower limb work during prior swimming; Objectif. – Étudier l’influence d’une épreuve de natation sur la dépense énergétique dans l’exercice de cyclisme subséquent lors de l’enchaînement cyclisme–natation d’un triathlon.Méthodes. – Dix triathlètes entraînés ont participé à 3 enchaînements natation–cyclisme et une épreuve isolée de cyclisme (épreuve C). L’exercice de cyclisme comprenait 15 minutes sur ergocycle à une puissance correspondant au seuil ventilatoire +5 %. Durant les enchaînements, cet exercice était précédé d’épreuves de natation sollicitant différentes masses musculaires, réalisées pendant la même durée à une allure de compétition sur 750 m (nage avec les bras et les jambes : NC, nage avec les bras uniquement : NB, nage avec les jambes uniquement : NJ).Résultats. – Une augmentation significative de la dépense énergétique en cyclisme est observée à la suite des épreuves de natation NB et NC, par rapport à l’épreuve isolée (p < 0,05). En revanche, le rendement du cyclisme est identique dans les conditions NB et NC (p > 0,05).Conclusion. – Une épreuve préalable de natation intense altère la dépense énergétique en cyclisme, notamment par les ajustements thermorégulatoires et le coût du travail respiratoire qu’elle induit. L’adaptation physiologique en cyclisme ne semble pas dépendre de l’importance du travail des jambes en natation.

International audience; The purpose of tlùs study was to investigate the effect of an exercise duration similar to triathlon' s cyclism event ("' 1 h), on factors determining the freely chosen cadence. Nine trained triathletes completed a cycling track session conducted at a speed corresponding to 75 % of maximal heart rate. Tiùs session was composed of five submaximal rides performed at five cadences presented in a random order (65, 80, 95, llO rpm and freely chosen cadence) realized before and after a one hour exercise at the freely chosen cadence. Results show, during the frrst condition, that triathletes choose spontaneously a cadence (90, 1 ± 10,7 rpm) close to the neuromuscular optimum (89,6 ± 1,1 rpm) while at the end ofexercise, a decrease of the freely chosen cadence (82,8 ± 8,7 rpm) was observed towards the energetically optimal cadence (78,6 ± 5,8 rpm). These findings suggest the hypothesis of a adaptation of the movement pattern with the exercice duration in order to minimize the energy cost rather than the neuromuscular cost of cycling.; L'objectif de ce travail est d'étudier l'effet d'une durée d'exercice, spécifique à la partie cyclisme d'un triathlon de courte distance ("'1h), sur les facteurs qui déterminent le libre choix d'une cadence de pédalage. Neuf triathlètes entraînés ont réalisé une épreuve de cyclisme sur vélodrome à une vitesse qui représentait 7 5 % de la fréquence cardiaque maximale. Cette épreuve se composait de cinq paliers sous-maximaux correspondant à cinq cadences distribuées dans un ordre aléatoire (65, 80, 95, 110 tours.min-1 et la cadence librement choisie) réalisés avant et après une heure d'exercice à la fréquence librement choisie. Les résultats montrent qu'au début de l'exercice, les triathlètes adoptent spontanément une cadence (90,1 ± 10,7 tours.min- 1) qui se rapproche de l'optimum neuromusculaire (89,6 ± 1,1 tours.min-1) alors qu'en fm d'épreuve, la cadence libre (82,8 ± 8,7 tours.min-1 ) diminue significativement et se décale vers l'optimum énergétique (78,6 ± 5,8 tours.min-1). La discussion envisage l'hypothèse d'une modification du critère de choix de la cadence avec la durée de l'exercice privilégiant plus une minimisation du coût énergétique que du « coût neuromusculaire ».

International audience; The purpose of this study was to examine the relationship between cadence and oxygen consumption with exercise dura-tian. Ten triathletes who trained regularly were examined. The first test was always a maximal test to determine maximal oxy~ gen uptake (VOzmax). The other sessions were composed of six submaximal tests representing 80% of the maximal power reached with VOzmax (Pmax). During these tests submaximal rides with a duration of 30 min were performed. Each test represented , in a randomised arder, one of the following pedal rates: 50, 65, Bd, 95,110 rpm and a freely-chosen rate. \/0 2 , respiratory parameters, and heart rate were monitored continuously. Two periods, between the 3rd and the 6th minute and between the 25th and the 28th minute, were analysed. Results showed that when \/0 2 and heart rate were plotted against cadence, each curve could be best described by a parabolic function, whatever the period. Furthermore, a significant effect of period was fou nd on energetically optimal cadence (70 ± 4.5 vs. 86 ± 6.2 rpm, P < 0.05). Only during the second period was no significant difference found between freely-chosen cadence (83 ± 6.9 rpm} and energetically optimal cadence (P > 0.05). ln conclusion, our results suggest that during prolonged exercise triathletes choose a cadence that is close to the energetically optimal cadence. A change of muscle fibre recruitment pattern with exercise duration and cadence Would explain the shift in energetically optimal rate towards a higher pedal rate observed at the end of exercise. •