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Le Touquet – Paris-Plage, France

Mouraby R.,Institute Of Recherche Biomedicale Et Depidemiologie Du Sport | Mouraby R.,University of Paris Descartes | Tafflet M.,Institute Of Recherche Biomedicale Et Depidemiologie Du Sport | Tafflet M.,French Institute of Health and Medical Research | And 7 more authors.
Science and Sports

Aim: To assess the reproducibility and relevancy of the tests that composed the Diagnoform physical fitness estimation procedure. Methods and results: We studied 183subjects twice, who were divided into groups of age and physical activity intensity. Correlations between both sessions have been calculated. Reproducibilities are good to very good. Some correlation coefficients show strong relationships between tests involving muscular power suggesting a possible redundancy in the assessment of this capacity. Conclusion: Diagnoform is an efficient tool to assess the level of physical fitness in populations. © 2011 Elsevier Masson SAS. Source

Berthelot G.,IRMES | Berthelot G.,University of Paris Descartes | Len S.,IRMES | Hellard P.,IRMES | And 10 more authors.

The physiological parameters characterizing human capacities (the ability to move, reproduce or perform tasks) evolve with ageing: performance is limited at birth, increases to a maximum and then decreases back to zero at the day of death. Physical and intellectual skills follow such a pattern. Here, we investigate the development of sport and chess performances during the lifetime at two different scales: the individual athletes' careers and the world record by age class in 25 Olympic sports events and in grandmaster chess players. For all data sets, a biphasic development of growth and decline is described by a simple model that accounts for 91.7%of the variance at the individual level and 98.5% of the variance at the species one. The age of performance peak is computed at 26.1 years old for the events studied (26.0 years old for track and field, 21.0 years old for swimming and 31.4 years old for chess). The two processes (growth and decline) are exponential and start at age zero. Both were previously demonstrated to happen in other human and non-human biological functions that evolve with age. They occur at the individual and species levels with a similar pattern, suggesting a scale invariance property. © The Author(s) 2011. Source

Desgorces F.-D.,Institute Of Recherche Biomedicale Et Depidemiologie Du Sport Irmes | Desgorces F.-D.,University of Paris Descartes | Thomasson R.,Institute Of Recherche Biomedicale Et Depidemiologie Du Sport Irmes | Thomasson R.,University of Paris Descartes | And 8 more authors.
Aging Clinical and Experimental Research

Background: Individual’s one-repetition maximum (1-RM) is required to calculate and prescribe intensity for resistance training, while testing protocols enhance the risk of injuries and are time-consuming. Aims: The aim of the present study was to assess the accuracy of 1-RM prediction from ratings of perceived exertion (RPE) of resistance exercises performed at submaximal sets (intensity and volume) in older adult males before and after a 12-week rehabilitation program. Methods: 18 untrained subjects (70.4 ± 4.5 years) first completed a 1-RM direct assessment with a horizontal leg press pre- and post-training. Thereafter, participants performed, in a random order, 2-repetition sets with loads unknown to them (corresponding to 20, 45 and 70 % of 1-RM). The RPE was recorded immediately after the sets. That RPE associated to its corresponding load was subjected to a linear regression analysis to extrapolate the maximal RPE score and its corresponding 1-RM. Results: RPE and relative intensities of sets appeared related pre- [r2 = 0.59, standard error of estimate (SEE) = 13.3 %] and post-training (r2 = 0.83, SEE = 8.1 %). Differences between measured and predicted 1-RM were reduced from the beginning to the end of training but standard deviations remained high (17.4 ± 11.8 vs. 4.2 ± 11.1 kg). Pre-training, 1-RM expressed relatively to body weight was negatively related with the errors of 1-RM predictions (r2 = 0.39, p = 0.03). Conclusions: In older subjects, RPE may be used to predict 1-RM; however, the predicted value deviates considerably from the measured one, necessitating cautious application. Importantly, this method allows to capture training-induced change in 1-RM, thus making possible assessing training’s effectiveness and allowing its modification if necessary. © 2015, Springer International Publishing Switzerland. Source

Desgorces F.-D.,Institute Of Recherche Biomedicale Et Depidemiologie Du Sport | Desgorces F.-D.,University of Paris Descartes | Berthelot G.,Institute Of Recherche Biomedicale Et Depidemiologie Du Sport | Berthelot G.,University of Paris Descartes | And 8 more authors.
Journal of Evolutionary Biology

Running speed in animals depends on both genetic and environmental conditions. Maximal speeds were here analysed in horses, dogs and humans using data sets on the 10 best performers covering more than a century of races. This includes a variety of distances in humans (200-1500m). Speed has been progressing fast in the three species, and this has been followed by a plateau. Based on a Gompertz model, the current best performances reach 97.4% of maximal velocity in greyhounds to 100.3 in humans. Further analysis based on a subset of individuals and using an 'animal model' shows that running speed is heritable in horses (h2=0.438, P=0.01) and almost so in dogs (h2=0.183, P=0.08), suggesting the involvement of genetic factors. Speed progression in humans is more likely due to an enlarged population of runners, associated with improved training practices. The analysis of a data subset (40 last years in 800 and 1500m) further showed that East Africans have strikingly improved their speed, now reaching the upper part of the human distribution, whereas that of Nordic runners stagnated in the 800m and even declined in the 1500m. Although speed progression in dogs and horses on one side and humans on the other has not been affected by the same genetic/environmental balance of forces, it is likely that further progress will be extremely limited. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology. Source

Desgorces F.D.,University of Paris Descartes | Le Page C.,University of Paris Descartes | Le Page C.,University of Evry Val dEssonne | Police C.,University of Paris Descartes | And 9 more authors.
Hormone and Metabolic Research

Perturbations of energy balance induce compensatory processes that may alter expected weight loss. In obese patients, our aim was to investigate the relationships that occurred between fasting plasma concentrations of anorexigenic peptides and metabolic parameters, appetite, physical capacity, and weight loss in the 5 first days of a program associating exercise and caloric reduction. Thirteen obese women were monitored from day 1 to day 5 with 2 exercise sessions in day 2 and day 4. We measured, in a fasted state, changes in body weight, hunger ratings, and plasma concentrations of fatty acids, triglycerides, leptin, insulin, amylin, peptide YY, and insulin-resistance index. Physical performance was assessed by a 6-min walking test. The program resulted in significantly reduced body weight (0.75±0.4kg; p=0.001), of plasma concentrations of triglycerides, insulin, amylin, peptide YY, and the insulin-resistance index, and also increased fatty acids (p<0.05). Hunger ratings were increased (p<0.05). Program-induced changes in fatty acids, leptin, and insulin concentrations were related to physical performance (r2=0.45, 0.59, and 0.52; p<0.05, respectively) and to weight loss (r2=0.65, 0.57, 0.55; p<0.05, respectively). Five days of diet and exercise induced weight loss, improved lipid profile, and decreased insulin resistance while hunger ratings increased. Subjects with higher physical capacity lost more weight, presented higher increases in fatty acids and lower changes of leptin and insulin concentrations suggesting a better metabolic flexibility. To reduce the compensatory responses that can occur with energy imbalances, our study supports to account for individual activity level before prescribing weight-loss program associating diet and exercise. Source

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