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ObjectivesTo identify individual characteristics associated with the adoption of injury risk reduction programmes (IRRP) and to investigate the variations in sociocognitive determinants (ie, attitudes, subjective norms, perceived behavioural control and intentions) of IRRP adoption in athletics (track and field) athletes.MethodsWe conducted a cross-sectional study using an online survey sent to athletes licensed with the French Federation of Athletics to investigate their habits and sociocognitive determinants of IRRP adoption. Sociodemographic characteristics, sports practice and history of previous injuries were also recorded. Logistic regression analyses and group comparisons were performed.ResultsThe final sample was composed of 7715 athletes. From the multivariable analysis, competing at the highest level was positively associated with IRRP adoption (adjusted OR (AOR)=1.66; 99.9% CI 1.39 to 1.99 and AOR=1.48; 99.9% CI 1.22 to 1.80) and presenting a low number of past injuries was negatively associated with IRRP adoption (AOR=0.48; 99.9% CI 0.35 to 0.65 and AOR=0.61; 99.9% CI 0.44 to 0.84), both during their lifetime and the current season, respectively. These results were supported by higher scores of sociocognitive determinants among athletes who reported IRRP adoption compared with other athletes.ConclusionSome characteristics of athletes seem to be associated with IRRP adoption either positively (competing at the highest level) or negatively (presenting a lower number of past injuries), whereas all the sociocognitive determinants tested appear to be linked to IRRP adoption. Since many athlete characteristics are difficult or impossible to change, IRRP promotion may be enhanced by targeting athletes’ beliefs and intentions to adopt an IRRP.

International audience; Objective: To analyse the rates of lower limb muscle injuries in athletics disciplines requiring different running velocities during international athletics championships.Design: Prospective total population study.Methods: During 13 international athletics championships (2009–2019) national medical teams and local organizing committee physicians daily reported all newly incurred injuries using the same study design, injury definition and data collection procedures. In-competition lower limb muscle injuries of athletes participating in disciplines involving running (i.e. sprints, hurdles, jumps, combined events, middle distances, long distances, and marathon) were analysed.Results: Among the 12,233 registered athletes, 344 in-competition lower limb muscle injuries were reported (36% of all in-competition injuries). The proportion, incidence rates and injury burden of lower limb muscles injuries differed between disciplines for female and male athletes. The most frequently injured muscle group was hamstring in sprints, hurdles, jumps, combined events and male middle distances runners (43–75%), and posterior lower leg in female middle distances, male long distances, and female marathon runners (44–60%). Hamstring muscles injuries led to the highest burden in all disciplines, except for female middle distance and marathon and male long distance runners. Hamstring muscles injury burden was generally higher in disciplines requiring higher running velocities, and posterior lower leg muscle injuries higher in disciplines requiring lower running velocities.Conclusions: The present study shows discipline-specific injury location in competition context. Our findings suggest that the running velocity could be one of the factors that play a role in the occurrence/location of muscle injuries.

Resume Introduction Mieux comprendre les consequences psychologiques d’une blessure et l’influence de celle-ci sur les modifications de comportement et la realisation d’un programme de prevention semble pertinent pour la prise en charge therapeutique et dans une optique de prevention. Ainsi, l’objectif de cette presente etude a donc ete (1) d’analyser la perception des blessures par les athletes, et (2) d’analyser l’influence de celles-ci sur la realisation de mesures de prevention. Methodes Nous avons conduit une etude observationnelle quantitative retrospective nationale de recueil du ressenti des athletes de competition licencies a la Federation francaise d’athletisme vis-a-vis de leurs antecedents de blessures, leur perception de la blessure et les programmes de prevention des blessures, par un questionnaire informatique envoye aux athletes au printemps 2020. Resultats Au total, 7712 reponses d’athletes ont ete incluses dans cette analyse, incluant 37 % de femmes et 63 % d’hommes, âges de 37,9 ± 14,8 ans (de 18 a 87 ans), allant de niveau international a departemental, couvrant toutes les disciplines de l’athletisme. Soixante-dix pour cent des athletes n’avaient jamais realise de programme de prevention des blessures durant leur carriere, alors que 30 % estimaient en avoir suivi un de maniere partielle ou totale. Quatre-vingt dix pour cent des athletes avaient eu au moins une blessure depuis le debut de leur pratique. Les sportifs rapportaient qu’une blessure engendrait une tristesse, une frustration, un degout et une preoccupation de se refaire mal au meme endroit. Ils etaient conscients qu’une mauvaise prise en charge pouvait entrainer une recidive ou une nouvelle blessure. Les athletes avec antecedent de blessure realisaient significativement plus un programme de prevention des lesions que ceux ne s’etant jamais blesses. Ceux s’etant deja blesses croyaient en l’efficacite des programmes de prevention, davantage que ceux sans antecedent de blessure. En revanche, il n’y avait pas de difference de perception de l’interet de mesures preventives telles que l’hygiene de vie, l’ecoute de son corps, de ses douleurs et de sa fatigue entre les athletes avec et sans antecedent de blessures. Conclusion Une blessure peut entrainer des consequences psychologiques non negligeables pour l’athlete. Ses repercussions sont importantes a prendre en compte dans la prise en charge globale des lesions.

Couderc, A, Gabbett, TJ, Piscione, J, Robineau, J, Peeters, A, Igarza, G, Thomas, C, Hanon, C, and Lacome, M. Repeated high-intensity effort activity in international male Rugby Sevens. J Strength Cond Res XX(X): 000-000, 2018-Rugby Sevens is characterized by repeated high-intensity accelerations, sprinting, and collisions, commonly referred to as repeated high-intensity effort (RHIE) activity. Although repeated acceleration and sprinting activity of Rugby Sevens has been investigated, to date, no study has investigated the repeated running and collision activity of international Rugby Sevens during competitive events. In this study, 15 elite players competed in 44 matches during the HSBC World Sevens Series. Global positioning systems and match analysis software were used to quantify the frequency of repeated running and collision efforts. High acceleration (≥2.5 m·s), high speed (above maximal aerobic speed), sprint (above 85% of maximal sprint speed), and collision efforts (tackles, ruck, and contact) were considered as high-intensity effort activities. An RHIE bout was defined as 3 or more high-intensity efforts with less than 21 seconds recovery between efforts. The difference between positional groups (forward and backs) and first and second halves was compared using magnitude-based inferential statistics. One hundred twelve individual match observations were analyzed. On average, players performed 27 high-intensity effort events across the game. The distribution of high-intensity efforts included the following: 37% collisions, 34% accelerations, 27.5% high-velocity running, and 1.5% sprints. An average of 3.7 RHIE bouts was performed per player. The difference in high-intensity efforts and number of RHIE bouts performed were trivial/small when compared between first and second halves, and between forward and back positional groups. Repeated high-intensity effort bouts play an important role in the activity profile of elite Rugby Sevens players. This study could provide a framework for performance analysts and coaches to analyze match-related performance of elite Rugby Sevens players, taking into account both the high-intensity running and collision components of the game. Coaches should implement training interventions to ensure the maintenance of RHIE performance during competitive events.

Purpose:To investigate the running demands and associated metabolic perturbations during an official rugby sevens tournament.Methods:Twelve elite players participated in 7 matches wearing GPS units. Maximal sprinting speed (MSS) and maximal aerobic speed (MAS) were measured. High-intensity threshold was individualized relative to MAS (>100% of MAS), and very-high-intensity distance was reported relative to both MAS and MSS. Blood samples were taken at rest and after each match.Results:Comparison of prematch and postmatch samples revealed significant (P < .01) changes in pH (7.41–7.25), bicarbonate concentration ([HCO3–]) (24.8–13.6 mmol/L), and lactate concentration ([La]) (2.4–11.9 mmol/L). Mean relative total distance covered was 91 ± 13 m/min with ~17 m/min at high-intensity. Player status (whole-match or interchanged players), match time, and total distance covered had no significant impact on metabolic indices. Relative distance covered at high intensity was negatively correlated with pH and [HCO3–] (r = .44 and r = .42, respectively; P < .01) and positively correlated with [La] (r = .36; P < .01). Total distance covered and distance covered at very high intensity during the 1-min peak activity in the last 3 min of play were correlated with [La] (r = .39 and r = .39, respectively; P < .01).Conclusions:Significant alterations in blood-metabolite indices from prematch to postmatch sampling suggest that players were required to tolerate a substantial level of acidosis related to metabolite accumulation. In addition, the ability to produce energy via the glycolytic energy pathway seems to be a major determinant in match-related running performance.

International audience; This study aimed to compare the response of salivary hormones of track and field athletes induced by preparation and pre-competitive training periods in an attempt to comment on the physiological effects consistent with the responses of each of the proteins measured. Salivary testosterone, cortisol, alpha-amylase, immunoglobulin A (IgA), chromogranin A, blood creatine kinase activity, and profile of mood state were assessed at rest in 24 world-class level athletes during preparation (3 times in 3 months) and pre-competitive (5 times in 5 weeks) training periods. Total mood disturbance and fatigue perception were reduced, while IgA (+61%) and creatine kinase activity (+43%) increased, and chromogranin A decreased (−27%) during pre-competitive compared to preparation period. A significant increase in salivary testosterone (+9 to +15%) and a decrease in testosterone/cortisol ratio were associated with a progressive reduction in training load during pre-competitive period (P < 0.05). None of the psycho-physiological parameters were significantly correlated to training load during the pre-competitive period. Results showed a lower adrenocortical response and autonomic activity, and an improvement of immunity status, in response to the reduction in training load and fatigue, without significant correlations of salivary hormones with training load. Our findings suggest that saliva composition is sensitive to training contents (season period) but could not be related to workload resulting from track and field athletics training.

International audience; Hanon, C, Savarino, J, and Thomas, C. Blood lactate and acid-base balance of world-class amateur boxers after three 3-minute rounds in international competition. J Strength Cond Res 29(4): 942–946, 2015—To examine the blood metabolic responses of world-class boxers involved in international competition (Test match), 33 male boxers (mean 6 SD) competing internationally across all the official weight categories were studied on 2 different occasions: Test match 1 (team A against team B) and Test match 2 (team A against team C). Blood samples were collected after the third round for both Test matches for all teams except team B. For all Test matches and boxers, mean blood lactate concentration ([BLac]), bicarbonate concentration, hemo-globin O 2 saturation (SaO 2), partial pressure for CO 2 (PCO 2), and pH were 13.6 6 2.4 mmol$L 21 , 13.2 6 2.3 mmol$L 21 , 95.0 6 2.6%, 32.0 6 5.5 mm Hg, and 7.22 6 0.06 with 7/20 final pH values ,7.20. The intermediate category (60–64 kg) was characterized by the greatest [BLac] (14.8 6 2.9) compared with the heaviest and lighter boxers (;12 mmol$L 21). During the second match (team A again team C), a significant difference between pH, PCO 2 , and SaO 2 values was observed with no concomitant difference in [BLac] suggesting a better buffering capacity in team A. This result highlights the need for a well-developed anaerobic and buffering capacity and indicates that world-class boxers must be able to tolerate a substantial level of acidosis to produce high levels of boxing activity until the end of a match.

The purpose of this study was to analyze 2 different long-sprint training programs (TPs) of equal total work load, completed either with short recovery (SR) or long recovery (LR) between sets and to compare the effects of 6 long-sprint training sessions (TSs) conducted over a 2-week period on a 300-m performance. Fourteen trained subjects performed 3 pretraining maximal sprints (50-, 100-, and 300-m), were paired according to their 300-m performance, and randomly allocated to an LR or SR group, which performed 6 TSs consisting of sets of 150, 200, or 250 m. The recovery in the LR group was double that of the SR group. During the third TS and the 300-m pretest and posttest, blood pH, bicarbonate concentration ([HCO₃⁻]), excess-base (EB), and lactate concentration were recorded. Compared with a similar TS performed with SR, the LR training tends to induce a greater alteration of the acid-base balance: pH: 7.09 ± 0.08 (LR) and 7.14 ± 0.05 (SR) (p = 0.10), [HCO₃⁻]: 7.8 ± 1.9 (LR) and 9.6 ± 2.7 (SR) (p = 0.04), and EB: -21.1 ± 3.8 (LR) and -17.7 ± 2.8 (SR) (p = 0.11). A significant improvement in the 300-m performance between pre-TP and post-TP (42.45 ± 2.64 vs. 41.52 ± 2.45, p = 0.01) and significant decreases in pH (p < 0.01), EB (p < 0.001) and increase in [La] (p < 0.001) have been observed post-TP compared with those pre-TP. Although sprint training with longer recovery induces higher metabolic disturbances, both sprint training regimens allow a similar 300-m performance improvement with no concomitant significant progress in the 50- and 100-m performance.

International audience; The aim of this study was to compare the evolution of oxygen uptake ( _V O2) in specifically trained runners during runningtests based on the 400-, 800-, and 1500-m pacing strategies adopted by elite runners to optimize performance. Final velocitydecreased significantly for all three distances, with the slowest velocity in the last 100 m expressed relative to the peakvelocity observed in the 400 m (77%), 800 m (88%), and 1500 m (96%). Relative to the previously determined _V O2maxvalues, the respective _V O2peak corresponded to 94% (400 m) and 100% (800 and 1500 m). In the last 100 m, a decreasein _V O2 was observed in all participants for the 400-m (15.6+6.5%) and 800-m races (9.9+6.3%), whereas a nonsystematicdecrease (3.6+7.6%) was noted for the 1500 m. The amplitude of this decrease was correlated with thereduction in tidal volume recorded during the last 100 m of each distance (r¼0.85, P50.0001) and with maximal bloodlactate concentrations after the three races (r¼0.55, P50.005). The present data demonstrate that the 800 m is similar tothe 400 m in terms of decreases in velocity and _V O2.

This study aimed to investigate the oxygen uptake and metabolic responses during a 400-m run reproducing the pacing strategy used in competition. A portable gas analyser was used to measure the oxygen uptake (V˙O2) of ten specifically trained runners racing on an outdoor track. The tests included (1) an incremental test to determine maximal V˙O2(V˙O2max) and the velocity associated with V˙O2max(v−V˙O2max), (2) a maximal 400-m (400T) and 3) a 300-m running test (300T) reproducing the exact pacing pattern of the 400T. Blood lactate, bicarbonate concentrations [HCO−3], pH and arterial oxygen saturation were analysed at rest and 1, 4, 7, 10 min after the end of the 400 and 300T. The peak V˙O2V˙O2 recorded during the 400T corresponded to 93.9 ± 3.9% of V˙O2maxV˙O2max and was reached at 24.4 ± 3.2 s (192 ± 22 m). A significant decrease in V˙O2 (P < 0.05) was observed in all subjects during the last 100 m, although the velocity did not decrease below v−V˙O2max. The V˙O2 in the last 5 s was correlated with the pH (r = 0.86, P < 0.0005) and [HCO−3] (r = 0.70, P < 0.05) measured at the end of 300T. Additionally, the velocity decrease observed in the last 100 m was inversely correlated with [HCO−3][HCO3−] and pH at 300T (r = −0.83, P < 0.001, r = −0.69, P < 0.05, respectively). These track running data demonstrate that acidosis at 300 m was related to both the V˙O2 response and the velocity decrease during the final 100 m of a 400-m run.

We investigated the oxygen uptake response (V.O (2)) to a 1500-m test conducted using a competition race strategy. On an outdoor track, eleven middle-distance runners performed a test to determine V.O (2max), velocity associated with V.O (2max) (v-V.O (2max)) and a supramaximal 1500-m running test (each test at least two days apart). V.O (2max) response was measured with the use of a miniaturised telemetric gas exchange system (Cosmed, K4, Roma, Italy). The 1500-m running test was performed at a mean velocity of 107. 6 + 2 % v-V.O (2max). The maximal value of oxygen uptake recorded during the 1500-m test (V.O (2peak)) was reached by subjects at 75.9 + 7.5 s (mean + SD) (i.e., 459 +/- 59 m). The time to reach V.O (2max) (TV.O (2peak)) and the start velocity (200- to 400-m after the onset of the 1500 m) expressed in % v-V.O (2max) were negatively and significantly correlated (p < 0.05), but our results indicate that a fast start does not necessarily induce a good performance. These results suggest that V.O (2max) is reached by all the subjects at the onset of a simulated 1500-m running event and are therefore in contrast with previous results obtained during treadmill running.

International audience; This study analyses the changes in the electro-myographic activity (EMG) of six major muscles of the leg during an incremental running test carried out on a treadmill. These muscles, the gluteus maximus (GM), biceps femoris (BF), vastus lateralis (VL), rectus femoris (RF), tibialis anterior (TA) and gastrocnemius (Ga) are known to have quite different functions during running. The aim of this study was to develop a methodology adapted to the analysis of integrated EMG (iEMG) running results, and to test the chronology of the onset of fatigue of the major muscles involved in running. Nine well-trained subjects [ _ V O 2max 76 (2.9) ml.min À1 .kg À1 ] took part in this study. They completed a running protocol consisting of 4 min stages, incrementally increasing in speed until exhaustion. The EMG signal was recorded during ten bursts of activation analysed separately at 45 s and 3 min 40 s of each stage. During running, consideration of the alteration in stride frequency with either an increase in speed or the onset of fatigue appears to be an indispensable part of the assessment of muscular fatigue. This allows the comparison of muscular activation between the various stage speeds by the use of common working units. Distance seems to be the only working unit that allows this comparison and thus the determination of the appearance of fatigue during running. The biarticular hip-mobilising muscles (RF and BF), which present two different bursts of activation during one running cycle, are the muscles that show the earliest signs of fatigue.

We tested the hypothesis that time course of O (2) uptake (VO (2)) measured during a supramaximal exercise performed in the field is driven to maximal oxygen uptake (VO (2max)). On an outdoor track, five middle-distance male runners first performed a test to determine VO (2max) and a supramaximal 800-m running test at least two days apart. VO (2) response was measured from the start to the end of exercise with the use of a miniaturised telemetric gas exchange system (Cosmed K4). VO (2max) was reached by all subjects 45 +/- 11 s (mean +/- SD) after the onset of the 800-m race (i.e., 316 +/- 75 m), and was maintained during the next 33 +/- 6 s (i.e., 219 +/- 41 m). The mean relative exercise intensity of the 800 m was 120 % VO (2max). An unexpected significant decrease in VO (2) (24.1 +/- 7.0 %; p0.05) was observed in all subjects during the final 38 +/- 17 s (i.e., the last 265 +/- 104 m). We concluded that, at onset of a simulated 800 m running event, VO (2) is quickly projected towards the VO (2max), and then becomes limited by the achievable VO (2max). This race profile shown by all athletes is in some contrast to what can be expected from earlier findings in a laboratory setting.