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This study investigated the influence of heat pre-conditioning on the recovery of muscle torque, microvascular function, movement economy and stride mechanics following exercise-induced muscle damage (EIMD). Twenty male participants were equally assigned to a control (CON) and an experimental group (HEAT), and performed a 30-min downhill run (DHR) to elicit EIMD. HEAT group received three consecutive days of heat exposure (45.1 ± 3.2 min of hot water immersion at 42 °C) prior to DHR. Microvascular function (near-infrared spectroscopy), maximal voluntary contraction (MVC) torque of the knee extensors, as well as two treadmill-based steady-state runs performed below (SSR-1) and above (SSR-2) the first ventilatory threshold were assessed prior to DHR and repeated for four consecutive days post-DHR (D1-POST to D4-POST). The decline in MVC torque following EIMD was attenuated in HEAT compared with CON at D1-POST (p = 0.037), D3-POST (p = 0.002) and D4-POST (p = 0.022). Muscle soreness increased in both CON and HEAT, but was significantly attenuated in HEAT compared with CON at D2-POST (p = 0.024) and D3-POST (p = 0.013). Microvascular function decreased in CON from D1-POST to D3-POST (p = 0.009 to 0.018), and was lower compared with HEAT throughout D1-POST to D3-POST (p = 0.003 to 0.017). Pre-heat treatment decreased the magnitude of strength loss and muscle soreness, as well as attenuated the decline in microvascular function following EIMD. Heat treatment appears a promising pre-conditioning strategy when embarking on intensified training periods or competition.
Murali Sabapathy; Frankie Tan; Shadiq Al Hussein; Haiyum Jaafar; Franck Brocherie; Sebastien Racinais; Mohammed Ihsan. Effect of heat pre-conditioning on recovery following exercise-induced muscle damage. Current Research in Physiology 2021, 4, 155 -162.
AMA StyleMurali Sabapathy, Frankie Tan, Shadiq Al Hussein, Haiyum Jaafar, Franck Brocherie, Sebastien Racinais, Mohammed Ihsan. Effect of heat pre-conditioning on recovery following exercise-induced muscle damage. Current Research in Physiology. 2021; 4 ():155-162.
Chicago/Turabian StyleMurali Sabapathy; Frankie Tan; Shadiq Al Hussein; Haiyum Jaafar; Franck Brocherie; Sebastien Racinais; Mohammed Ihsan. 2021. "Effect of heat pre-conditioning on recovery following exercise-induced muscle damage." Current Research in Physiology 4, no. : 155-162.
Hyperthermia (targeted core temperature: 38.5°C) reduces the time between gastrocnemius medialis stimulation and the onset of plantar flexor force production in vivo. This reduction in electromechanical delay is concomitant to an earlier motion of muscle fascicle compared with thermoneutral environment. However, hyperthermia has no impact on the duration of force transmission along aponeurosis and tendon, thereby reflecting different effects of heat exposure on contractile and elastic properties of the muscle-tendon unit.
Adèle Mornas; Sébastien Racinais; Franck Brocherie; Marine AlHammoud; Robin Hager; Yanis Desmedt; Gaël Guilhem. Hyperthermia reduces electromechanical delay via accelerated electrochemical processes. Journal of Applied Physiology 2021, 130, 290 -297.
AMA StyleAdèle Mornas, Sébastien Racinais, Franck Brocherie, Marine AlHammoud, Robin Hager, Yanis Desmedt, Gaël Guilhem. Hyperthermia reduces electromechanical delay via accelerated electrochemical processes. Journal of Applied Physiology. 2021; 130 (2):290-297.
Chicago/Turabian StyleAdèle Mornas; Sébastien Racinais; Franck Brocherie; Marine AlHammoud; Robin Hager; Yanis Desmedt; Gaël Guilhem. 2021. "Hyperthermia reduces electromechanical delay via accelerated electrochemical processes." Journal of Applied Physiology 130, no. 2: 290-297.
The landscape of the professional and elite sport has changed enormously in recent years, with clubs/franchises and national federations performance support operating through specialized background staff roles. Although not uniformly embraced across all sports and countries, the expansion of such a model has led to the emergence of a managing position—generally termed performance director (Buchheit and Carolan, 2019)—to organize and supervise all the sports science and sports medicine servicing areas accessible to the head coach (and/or his technical staff) and athletes. The scientific support staffing base includes full-time sport scientists, physiologists, biomechanists, nutritionists, psychologists, and even more recently statisticians/data scientists, with some additional part-time input from expert/academic consultants (e.g., neuroscientists). Depending of the size and culture of the clubs/federations, a medical department covers the medical care and therapy related to training and competition, as well as the involvement of professional specialists for health management (Dijkstra et al., 2014). As an example, a National Football League (NFL) staff generally comprised five departments and as large as 13 full-time employees under the umbrella of the performance director (Figure 1A). All these departments operate in synergy and also “independently” with appropriate autonomy at times, with the performance director orchestrating the “front lines” in a holistic and comprehensive manner toward a common performance goal. Figure 1. The actual (A) and proposed (B) performance support model and its applied research process (C). AT, athletic trainer; CMO, chief medical officer; DB, defensive back; DL, defensive line; EVP, executive vice president; LB, linebacker; OL, offensive line; P/T, physical therapist; QB, quarterback; RB, running back; TE, tight end; WR, wide receiver. The impetus to drive a performance support model is directly related to assisting the coaching/front office staff on strategies to understand what winning looks like through analysis of key performance indicators and metrics (Halson et al., 2019). The performance model employs analysis technologies (e.g., global positioning system with embedded tri-axial accelerometers, gyroscope and magnetometer, wearable sensors) and scientific advances (e.g., innovative training or nutritional strategies) (Malone et al., 2019) to enhance player performance and maximize player availability (Drew et al., 2017) while maintaining their health integrity through an integrated health management system (Dijkstra et al., 2014). Despite the growing number of clubs/federations employing this approach, there are still many who do not choose to see this model as the vehicle to progress. Although this has been widely addressed (Bishop, 2008; Dijkstra et al., 2014; Buchheit, 2016, 2017; Coutts, 2016, 2017; McCall et al., 2016; Eisenmann, 2017; Nassis, 2017; Halperin, 2018; Sandbakk, 2018, 2019; Fullagar et al., 2019; Halson et al., 2019), here, the present opinion proposes to discuss past, actual, and new issues faced by the practitioners and researchers that are at the front line of professional and elite sport in order to reinforce the necessary evolution of professional squads and federations to stay at the cutting edge of performance optimization. Modern professional and elite sport has gained an interest in creating athlete-centered structures (e.g., Boston Celtics Auerbach training center, Ultimate Fighting Championship's performance institute in Las Vegas, Aspire Academy in Doha, Chicago Cubs' Arizona spring training performance center, and Wrigley field high-performance facility), which include state-of-the-art sport science facilities and material for performance optimization. Because the margin between winning and losing is tiny (Davison et al., 2009), such environments take into account all the factors surrounding athlete's performance, health, and well-being. In order to provide effective evidence-based, performance-oriented, and science-driven practices in sports science and sports medicine support, a positive integration is paramount, implying the organizational direction [i.e., owner, chief executive officers (CEOs), head coach, front office] to recognize and believe in the performance model and then favor the interaction between each department. As such, and because this has been reported to be a critical barrier (Fullagar et al., 2019), particular attention must be carried on ensuring that there is alignment between leadership/ownership and the performance team. This is especially ringing true on the “hands-on” staff (such as coaching, performance, and medical) that should view the overall picture of the organization culture and its performance model and develop coexistence and relationship based on different expertise enabling all staff. A clear holistic process with transparent roles and responsibilities facilitates decision-making regarding the somewhat paradoxal performance optimization and long-term health management (particularly relevant in youth elite sport environments) (Dijkstra et al., 2014). However, problems may occur if groups within the club/federation are not open to new innovative ideas and scientific methodologies based on evidence-based practices to the optimization of player performance and health. Fixed mindsets not only create problems for the integration of the performance model (Nassis, 2017) but also may create silos between the performance departments and coaches/front office staff (Eisenmann, 2017; Drust, 2019). Clear goals and expectations with regard to where current practices are at the club/federation will help to plan the evolution of the “here and now—winning today” and the “how do we maintain and sustain winning—success”. If early adopter or innovator profiles would be helpful for compliance and acceptance (Nassis,...
Franck Brocherie; Adam Beard. All Alone We Go Faster, Together We Go Further: The Necessary Evolution of Professional and Elite Sporting Environment to Bridge the Gap Between Research and Practice. Frontiers in Sports and Active Living 2021, 2, 1 .
AMA StyleFranck Brocherie, Adam Beard. All Alone We Go Faster, Together We Go Further: The Necessary Evolution of Professional and Elite Sporting Environment to Bridge the Gap Between Research and Practice. Frontiers in Sports and Active Living. 2021; 2 ():1.
Chicago/Turabian StyleFranck Brocherie; Adam Beard. 2021. "All Alone We Go Faster, Together We Go Further: The Necessary Evolution of Professional and Elite Sporting Environment to Bridge the Gap Between Research and Practice." Frontiers in Sports and Active Living 2, no. : 1.
Recent reports suggest that high‐altitude residence may be beneficial in the novel coronavirus disease (COVID‐19) implicating that traveling to high places or using hypoxic conditioning thus could be favorable as well. Physiological high‐altitude characteristics and symptoms of altitude illnesses furthermore seem similar to several pathologies associated with COVID‐19. As a consequence, high altitude and hypoxia research and related clinical practices are discussed for potential applications in COVID‐19 prevention and treatment. We summarize the currently available evidence on the relationship between altitude/hypoxia conditions and COVID‐19 epidemiology and pathophysiology. The potential for treatment strategies used for altitude illnesses is evaluated. Symptomatic overlaps in the pathophysiology of COVID‐19 induced ARDS and high altitude illnesses (i.e., hypoxemia, dyspnea…) have been reported but are also common to other pathologies (i.e., heart failure, pulmonary embolism, COPD…). Most treatments of altitude illnesses have limited value and may even be detrimental in COVID‐19. Some may be efficient, potentially the corticosteroid dexamethasone. Physiological adaptations to altitude/hypoxia can exert diverse effects, depending on the constitution of the target individual and the hypoxic dose. In healthy individuals, they may optimize oxygen supply and increase mitochondrial, antioxidant, and immune system function. It is highly debated if these physiological responses to hypoxia overlap in many instances with SARS‐CoV‐2 infection and may exert preventive effects under very specific conditions. The temporal overlap of SARS‐CoV‐2 infection and exposure to altitude/hypoxia may be detrimental. No evidence‐based knowledge is presently available on whether and how altitude/hypoxia may prevent, treat or aggravate COVID‐19. The reported lower incidence and mortality of COVID‐19 in high‐altitude places remain to be confirmed. High‐altitude illnesses and COVID‐19 pathologies exhibit clear pathophysiological differences. While potentially effective as a prophylactic measure, altitude/hypoxia is likely associated with elevated risks for patients with COVID‐19. Altogether, the different points discussed in this review are of possibly some relevance for individuals who aim to reach high‐altitude areas. However, due to the ever‐changing state of understanding of COVID‐19, all points discussed in this review may be out of date at the time of its publication.
Grégoire P. Millet; Tadej Debevec; Franck Brocherie; Martin Burtscher; Johannes Burtscher. Altitude and COVID‐19: Friend or foe? A narrative review. Physiological Reports 2020, 8, e14615 .
AMA StyleGrégoire P. Millet, Tadej Debevec, Franck Brocherie, Martin Burtscher, Johannes Burtscher. Altitude and COVID‐19: Friend or foe? A narrative review. Physiological Reports. 2020; 8 (24):e14615.
Chicago/Turabian StyleGrégoire P. Millet; Tadej Debevec; Franck Brocherie; Martin Burtscher; Johannes Burtscher. 2020. "Altitude and COVID‐19: Friend or foe? A narrative review." Physiological Reports 8, no. 24: e14615.
The purpose of this study is to evaluate the influence of competition level on running patterns for five playing position in the most successful 2014–2015 European rugby union team. Seventeen French rugby union championship and seven European rugby Champions Cup games were analysed. Global positioning system (sampling: 10 Hz) were used to determine high-speed movements, high-intensity accelerations, repeated high-intensity efforts and high-intensity micro-movements characteristics for five positional groups. During European Champions Cup games, front row forwards performed a higher number of repeated high-intensity efforts compared to National championship games (5.8±1.6 vs. 3.6±2.3; +61.1%), and back row forwards travelled greater distance both at high-speed movements (3.4±1.8 vs. 2.4±0.9 m·min-1; +41.7%) and after high-intensity accelerations (78.2±14.0 vs. 68.1 ±13.4 m; +14.8%). In backs, scrum halves carried out more high-intensity accelerations (24.7±3.1 vs. 14.8±5.0; +66.3%) whereas outside backs completed a higher number of high-speed movements (62.7±25.4 vs. 48.3±17.0; +29.8%) and repeated high-intensity efforts (13.5±4.6 vs. 9.7±4.9; +39.2%). These results highlighted that the competition level affected the high-intensity activity differently among the five playing positions. Consequently, training programs in elite rugby should be tailored taking into account both the level of competition and the high-intensity running pattern of each playing position.
Charly Fornasier-Santos; Gregoire P Millet; Paul Stridgeon; Olivier Girard; Franck Brocherie; Stéphane Nottin. High-intensity Activity in European vs. National Rugby Union Games in the best 2014–2015 Team. Laryngo-Rhino-Otologie 2020, 1 .
AMA StyleCharly Fornasier-Santos, Gregoire P Millet, Paul Stridgeon, Olivier Girard, Franck Brocherie, Stéphane Nottin. High-intensity Activity in European vs. National Rugby Union Games in the best 2014–2015 Team. Laryngo-Rhino-Otologie. 2020; ():1.
Chicago/Turabian StyleCharly Fornasier-Santos; Gregoire P Millet; Paul Stridgeon; Olivier Girard; Franck Brocherie; Stéphane Nottin. 2020. "High-intensity Activity in European vs. National Rugby Union Games in the best 2014–2015 Team." Laryngo-Rhino-Otologie , no. : 1.
Tadej Debevec; Grégoire P. Millet; Franck Brocherie. Do twelve normobaric hypoxic exposures indeed provoke relevant acclimatization for high-altitude workers? International Journal of Biometeorology 2020, 65, 637 -638.
AMA StyleTadej Debevec, Grégoire P. Millet, Franck Brocherie. Do twelve normobaric hypoxic exposures indeed provoke relevant acclimatization for high-altitude workers? International Journal of Biometeorology. 2020; 65 (4):637-638.
Chicago/Turabian StyleTadej Debevec; Grégoire P. Millet; Franck Brocherie. 2020. "Do twelve normobaric hypoxic exposures indeed provoke relevant acclimatization for high-altitude workers?" International Journal of Biometeorology 65, no. 4: 637-638.
We questioned whether changes in high-intensity locomotor and micro-movements patterns between the first and second part of each half depend on playing position in the 2014-2015 European rugby union championship winning team. Thirty-three rugby players were grouped according to five playing positions. Players were equipped with micro-electromechanical system including a GPS sampling at 10 Hz and high temporal resolution micro-sensors during 17 Top14 and 7 European games. High-speed movements, high-intensity accelerations, repeated high-intensity efforts, and high-intensity micro-movements were subsequently compared between four 20-min game periods. No significant group × time interactions were observed for any locomotor variables (p > 0.283). Irrespectively of playing position, the number of high-speed movements (p = 0.019), decreased from 0-20 min to 60-80 min as well as from 40-60 min to 60-80 min (p < 0.001) with high-intensity accelerations (p = 0.020) and repeated high-intensity efforts (p < 0.001). Significant group × time interaction was found for high-intensity micro-movements (p = 0.03) with a significant decrease observed in back row forwards from 0-20 to 60-80 min periods (-17.5%; ES = 0.6; p = 0.031). In elite rugby union, fatigue-induced changes during the last twenty minutes are independent from playing positions in high-intensity locomotor patterns in contrary to high-intensity micro-movements. Training drills that include specific repeated high-intensity efforts (high-speed and high-intensity accelerations efforts) may be useful to postpone match-related fatigue.
Charly Fornasier-Santos; Grégoire P. Millet; Paul Stridgeon; Franck Brocherie; Olivier Girard; Stéphane Nottin. How does playing position affect fatigue-induced changes in high-intensity locomotor and micro-movements patterns during professional rugby union games? European Journal of Sport Science 2020, 1 -11.
AMA StyleCharly Fornasier-Santos, Grégoire P. Millet, Paul Stridgeon, Franck Brocherie, Olivier Girard, Stéphane Nottin. How does playing position affect fatigue-induced changes in high-intensity locomotor and micro-movements patterns during professional rugby union games? European Journal of Sport Science. 2020; ():1-11.
Chicago/Turabian StyleCharly Fornasier-Santos; Grégoire P. Millet; Paul Stridgeon; Franck Brocherie; Olivier Girard; Stéphane Nottin. 2020. "How does playing position affect fatigue-induced changes in high-intensity locomotor and micro-movements patterns during professional rugby union games?" European Journal of Sport Science , no. : 1-11.
We determined whether running mechanics and leg muscle activity patterns for pre-activation (50 ms prior to foot contact) and loading (first half, second half and entire stance) phases vary between early, late and entire acceleration phases during repeated treadmill sprints. Ten male athletes performed three sets of five 5-s sprint accelerations (25-s and 3-min recovery between sprints and sets, respectively) on an instrumented treadmill. Ground reaction forces and surface EMG data (root mean square values of vastus lateralis, rectus femoris, biceps femoris, gastrocnemius medialis, gastrocnemius lateralis and tibialis anterior muscles of the right leg) corresponding to early, late and entire acceleration (steps 2, 4 and 6; steps 8, 10 and 12; and all steps, respectively) have been compared. Independently of fatigue, vertical and horizontal forces, contact time, step length, and step frequency differed as running velocity increased over different sprint acceleration sections (all P < 0.05). For pre-activation, first half, second half and entire stance phases taken separately, each of the six studied muscles displayed specific main sprint number and analysis section effects (all P < 0.05). However, there was in general no significant interaction between sprint number and analysis section (all P > 0.27). During repeated treadmill sprints, ground reaction force variables and leg muscle activity patterns can vary between early, late and entire acceleration phases. Identification of neuro-mechanical adjustments across the gait cycle with fatigue, however, did not differ when considering all steps or only a few steps during the early or late acceleration phases.
Olivier Girard; Franck Brocherie; Jean-Benoit Morin; Grégoire P. Millet; Clint Hansen. Running mechanics and leg muscle activity patterns during early and late acceleration phases of repeated treadmill sprints in male recreational athletes. Graefe's Archive for Clinical and Experimental Ophthalmology 2020, 120, 2785 -2796.
AMA StyleOlivier Girard, Franck Brocherie, Jean-Benoit Morin, Grégoire P. Millet, Clint Hansen. Running mechanics and leg muscle activity patterns during early and late acceleration phases of repeated treadmill sprints in male recreational athletes. Graefe's Archive for Clinical and Experimental Ophthalmology. 2020; 120 (12):2785-2796.
Chicago/Turabian StyleOlivier Girard; Franck Brocherie; Jean-Benoit Morin; Grégoire P. Millet; Clint Hansen. 2020. "Running mechanics and leg muscle activity patterns during early and late acceleration phases of repeated treadmill sprints in male recreational athletes." Graefe's Archive for Clinical and Experimental Ophthalmology 120, no. 12: 2785-2796.
Brocherie, F, Perez, J, and Guilhem, G. Effects of a 14-day high-intensity shock microcycle in high-level ice hockey players' fitness. J Strength Cond Res XX(X): 000–000, 2020—Elite athletes face congested schedules with increased competition frequency and restricted time for training periods. Therefore, time is lacking to design long-term sport-specific block periodization. This study aimed to investigate the effects of adding a 14-day off-ice high-intensity training (HIT) shock microcycle to the usual training content of the pre-season preparation of high-level male ice hockey players' fitness. Fourteen players were randomly assigned to off-ice HIT (n = 7) or usual pre-season training (control, n = 7). For the HIT group, additional off-ice training content included 2 sessions of repeated-maximal resistance training, 2 sessions of repeated-sprint training, and 2 sessions of high-intensity intermittent training. Control group performed equal number of off-ice sessions using traditional strength and conditioning training. Off-ice Yo-Yo intermittent recovery test level 2 (YYIR2) and on-ice repeated-sprint ability test (RSA) were conducted before (pre-test) and 3 days after the intervention (post-test). Statistical significance was set at p < 0.05. Significant group × time interactions were found for off-ice YYIR2 performance (p < 0.05) and on-ice RSA-cumulated skating time (RSATT; p < 0.05). Compared with pre-test, off-ice YYIR2 distance covered significantly increased (from 708.6 ± 97.2 to 885.7 ± 118.7 m, p < 0.01; +25.8 ± 16.9%, p < 0.05) and on-ice RSATT significantly decreased (from 28.35 ± 0.87 to 28.14 ± 0.84 seconds; −1.7 ± 2.1%, both p < 0.05)] for HIT group. No significant pre-test to post-test changes were found for the control group (+2.7 ± 20.0% for YYIR2 and +0.9 ± 2.2% for RSATT). The implementation of a 14-day shock microcycle (including 6 HIT sessions) significantly improved fitness performance in high-level male ice hockey players. Such HIT block periodization offers a promising way to deal with congested schedules.
Franck Brocherie; Jérôme Perez; Gaël Guilhem. Effects of a 14-Day High-Intensity Shock Microcycle in High-Level Ice Hockey Players' Fitness. Journal of Strength and Conditioning Research 2020, Publish Ah, 1 .
AMA StyleFranck Brocherie, Jérôme Perez, Gaël Guilhem. Effects of a 14-Day High-Intensity Shock Microcycle in High-Level Ice Hockey Players' Fitness. Journal of Strength and Conditioning Research. 2020; Publish Ah ():1.
Chicago/Turabian StyleFranck Brocherie; Jérôme Perez; Gaël Guilhem. 2020. "Effects of a 14-Day High-Intensity Shock Microcycle in High-Level Ice Hockey Players' Fitness." Journal of Strength and Conditioning Research Publish Ah, no. : 1.
This study describes asymmetry in the main running mechanical variables during repeated treadmill sprints in elite female athletes and examines whether inter-limb differences in sprinting mechanics increase with fatigue. Eighteen elite female players (French national Rugby Sevens team) performed 8 × 5-s sprints (25-s rest) on an instrumented motorised sprint treadmill. The group mean ‘symmetry angle’ (SA) scores were ~1–2% for contact time (1.6 ± 0.6%), aerial time (2.1 ± 0.8%), step frequency (1.3 ± 0.5%) and step length (1.6 ± 0.6%). Mean vertical and horizontal forces, vertical and leg stiffness presented SA values of 1.7 ± 1.5%, 2.4 ± 1.2%, 2.6 ± 0.2% and 2.5 ± 0.2%, respectively. The SA scores were ~2–8% for duration of braking (6.9 ± 5.0%) and propulsive (6.5 ± 4.4%) phases, peak braking (6.5 ± 2.5%) and propulsive (1.6 ± 0.9%) forces as well as net (5.8 ± 5.6%), braking (7.7 ± 5.3%) and propulsive (2.7 ± 1.6%) impulses. However, there was no influence of sprint repetition number on SA scores for tested variables (P > 0.05). In elite female Rugby Sevens players, there was no noticeable difference in asymmetries for the great majority of stride mechanical variables during repeated treadmill sprints.
Olivier Girard; Sébastien Racinais; Anthony Couderc; Jean-Benoit Morin; Joong Hyun Ryu; Julien Piscione; Franck Brocherie. Asymmetries during repeated treadmill sprints in elite female Rugby Sevens players. Sports Biomechanics 2020, 1 -11.
AMA StyleOlivier Girard, Sébastien Racinais, Anthony Couderc, Jean-Benoit Morin, Joong Hyun Ryu, Julien Piscione, Franck Brocherie. Asymmetries during repeated treadmill sprints in elite female Rugby Sevens players. Sports Biomechanics. 2020; ():1-11.
Chicago/Turabian StyleOlivier Girard; Sébastien Racinais; Anthony Couderc; Jean-Benoit Morin; Joong Hyun Ryu; Julien Piscione; Franck Brocherie. 2020. "Asymmetries during repeated treadmill sprints in elite female Rugby Sevens players." Sports Biomechanics , no. : 1-11.
This study is aimed to examine the acute responses to a blood flow restriction (BFR) low-intensity aerobic exercise, compared with a similar exercise without BFR, on several aerobic- and hypertrophy-related proteins expression and hormonal responses. On two different occasions, five healthy untrained male subjects were required to perform (i) a BFR low-intensity aerobic exercise consisting of 5 sets of 2-min bouts of walking at an exercise intensity of 63–65% HRmax (equivalent to 40% of VO2max), interspersed by 1-min rest; and (ii) similar exercise bouts without BFR (Ctrl). For each condition, venous blood samples were collected at pre- (baseline), immediately and 2-h post-exercise. Baseline and 3-h post-exercise muscle biopsy samples (vastus lateralis) were also performed for protein expression analysis. HIF-1α, PGC-1α, and VEGF proteins content were significantly higher (P < 0.05) at 3-h post-exercise in BFR compared with baseline values. In reference to baseline, phosphorylation of Akt also increased significantly (P < 0.05) following BFR, and in a greater extent (P < 0.05) than following Ctrl. IGF-1 concentration significantly increased (P = 0.001) immediately following BFR exercise than baseline values and serum GH showed a significant increase (P = 0.046) compared with Ctrl. The addition of blood flow restriction during walking exercise initiate a concomitant cell signaling pathways regulating mitochondrial biogenesis, angiogenesis, and skeletal muscle protein expression. Le but de cette étude est d’examiner les réponses aiguës à un exercice aérobie de faible intensité réalisé avec ou sans occlusion vasculaire (blood flow restriction, [BFR]) sur l’expression de protéines impliquées dans le développement de l’hypertrophie et de l’endurance. Selon un plan croisé, 5 sujets sains non entraînés ont réalisé à deux occasions différentes: (i) 5 séries de 2 min de marche à 63–65 % de la fréquence cardiaque maximale (équivalent à 40 % de la consommation maximale d’oxygène) entrecoupées de 1 min de repos, le tout sous occlusion vasculaire des membres inférieurs (BFR); et (ii) le même exercice sans occlusion (Ctrl). Pour chaque condition, des échantillons sanguins ont été prélevés avant, immédiatement après et 2 h après chaque condition. Des biopsies musculaires (vastus lateralis) ont également été pratiquée au repos (avant exercice) et 3 h après. Le contenu protéique du facteur induit par l’hypoxie 1 alpha (Hypoxic Inducible Factor 1α, HIF-1α), de peroxisome proliferator-activated receptor gamma-coactivator-1alpha (PGC-1α), et du facteur de croissance de l’endothélium vasculaire (Vascular Endothelial Growth Factor, VEGF) ont significativement augmenté (p < 0,05) après l’exercice aérobie BFR. La phosphorylation de la protéine kinase B (Akt) a également augmenté de manière significative (p < 0,05) après l’exercice aérobie BFR et dans une plus grande proportion (p < 0,05) que suite à l’exercice Ctrl. La concentration du facteur de croissance Insulin-like Growth Factor-1 (IGF-1) augmente (p < 0,001) immédiatement après l’exercice aérobie BFR et l’hormone de croissance (sérum GH) augmente significativement (p < 0,05) en comparaison avec Ctrl. L’ajout d’une restriction de la circulation sanguine au cours d’un exercice de marche stimule des voies de signalisation musculaire concomitantes régulant la biogenèse mitochondriale, l’angiogenèse et l’expression des protéines du muscle squelettique.
A. Barjaste; B. Mirzaei; F. Rahmani-Nia; R. Haghniyaz; Franck Brocherie. Concomitant aerobic- and hypertrophy-related skeletal muscle cell signaling following blood flow-restricted walking. Science & Sports 2020, 36, e51 -e58.
AMA StyleA. Barjaste, B. Mirzaei, F. Rahmani-Nia, R. Haghniyaz, Franck Brocherie. Concomitant aerobic- and hypertrophy-related skeletal muscle cell signaling following blood flow-restricted walking. Science & Sports. 2020; 36 (2):e51-e58.
Chicago/Turabian StyleA. Barjaste; B. Mirzaei; F. Rahmani-Nia; R. Haghniyaz; Franck Brocherie. 2020. "Concomitant aerobic- and hypertrophy-related skeletal muscle cell signaling following blood flow-restricted walking." Science & Sports 36, no. 2: e51-e58.
This study aimed to investigate the correlations between players’ mechanical capacities determined during off- and on-ice tests. Whole body force-velocity relationships were assessed in elite female ice hockey players (n = 17) during jumping [squat jump (SJ)], running (5 m and 30 m) and skating (5 m and 40 m) sprint tasks. Mechanical capacities estimates include relative maximal theoretical force (F0rel), velocity (V0), power (Pmaxrel), slope of the linear relationship between force relative to body mass and velocity (SFVrel), maximal horizontal component of the ground reaction force to the corresponding resultant force (RFmax) and minimal rate of decrease of this ratio (DRF). On-ice mechanical capacities (F0rel, Pmaxrel, RFmax and DRF) largely-to-very largely correlated with 40-m skating split time (r ranging from 0.82 for DRF to -0.91 for Pmaxrel; p < 0.001). Performance variables (SJ height, 30-m running and 40-m forward skating split time) and Pmaxrel demonstrated the largest associations between jumping, running and skating tasks (r ranging from -0.81 for 30-m sprint running time to 0.92 for SJ height; p < 0.001). Small (V0, SFVrel, DRF and force-velocity deficit) to very large (Pmaxrel) correlations (r ranging from 0.58 to 0.72; p < 0.05) were obtained between mechanical variables inferred from off- and on-ice force-velocity tests. The capacity to generate high amounts of horizontal power and effective horizontal force during the first steps on the ice is paramount for forward skating sprint performance. Mechanical capacities determined during forward skating sprint could be considered in ice hockey testing to identify fitness and/or technical/training requirements.
Jérôme Perez; Gaël Guilhem; Robin Hager; Franck Brocherie. Mechanical determinants of forward skating sprint inferred from off- and on-ice force-velocity evaluations in elite female ice hockey players. European Journal of Sport Science 2020, 21, 192 -203.
AMA StyleJérôme Perez, Gaël Guilhem, Robin Hager, Franck Brocherie. Mechanical determinants of forward skating sprint inferred from off- and on-ice force-velocity evaluations in elite female ice hockey players. European Journal of Sport Science. 2020; 21 (2):192-203.
Chicago/Turabian StyleJérôme Perez; Gaël Guilhem; Robin Hager; Franck Brocherie. 2020. "Mechanical determinants of forward skating sprint inferred from off- and on-ice force-velocity evaluations in elite female ice hockey players." European Journal of Sport Science 21, no. 2: 192-203.
Olympic distance cross-country cycling (XCO) is a discipline subject to wide performance variability due to uncontrollable environmental factors such as altitude, ambient temperature and/or humidity. This study therefore aimed to investigate the impact of environmental factors on XCO performance in under-23 and elite female and male categories. Individual data were collected from Continental Cup, World Cup, World Championship, and Olympics Games for U23 and elite female and male categories from 2009 to 2018. Factors included were race time (range: 55–157 min), average speed (range: 7.6–32.2 km/h), distance (range: 15.2–48.4 km), altitude (range: 50–2680 m), ambient temperature (range 7–41°C), relative and absolute humidity (range: 8–97% and 2.4–25.3 g/m3, respectively), and categories. The analysis represents 10,966 individual data which indicate a continuous progression of the performance for all categories. Principal component analysis reveals that the slowest XCO performance was resulting from high ambient temperature and absolute humidity. Regressions revealed that only altitude (P < 0.0001) have a direct linear negative effect on XCO average speed. A significant negative interaction effect of altitude with absolute humidity (P < 0.0001) on XCO average speed was also found. In addition, the higher the absolute humidity, the higher is the impact of ambient temperature (P < 0.0001) on XCO average speed. While XCO performance progressed over time regardless of the categories, results also indicate that altitude, ambient temperature, and absolute humidity negatively impact XCO performance. LOESS: local estimated scatterplot smoothing; PCA: Principal component analysis; UCI: Union Cycliste Internationale; U23: under-23; VO2max: maximal oxygen uptake; XCO: cross-country cycling.
Franck Brocherie; Simon Fischer; Quentin De Larochelambert; Henri Meric; Florence Riera. Influence of environmental factors on Olympic cross-country mountain bike performance. Temperature 2020, 7, 149 -156.
AMA StyleFranck Brocherie, Simon Fischer, Quentin De Larochelambert, Henri Meric, Florence Riera. Influence of environmental factors on Olympic cross-country mountain bike performance. Temperature. 2020; 7 (2):149-156.
Chicago/Turabian StyleFranck Brocherie; Simon Fischer; Quentin De Larochelambert; Henri Meric; Florence Riera. 2020. "Influence of environmental factors on Olympic cross-country mountain bike performance." Temperature 7, no. 2: 149-156.
Franck Brocherie; Grégoire P. Millet. Hypoxic exercise as an effective nonpharmacological therapeutic intervention. Experimental & Molecular Medicine 2020, 52, 529 -530.
AMA StyleFranck Brocherie, Grégoire P. Millet. Hypoxic exercise as an effective nonpharmacological therapeutic intervention. Experimental & Molecular Medicine. 2020; 52 (3):529-530.
Chicago/Turabian StyleFranck Brocherie; Grégoire P. Millet. 2020. "Hypoxic exercise as an effective nonpharmacological therapeutic intervention." Experimental & Molecular Medicine 52, no. 3: 529-530.
Beard, A, Ashby, J, Chambers, R, Millet, GP, and Brocherie, F. Wales Anaerobic Test (WAT): Reliability and fitness profiles of international rugby union players. J Strength Cond Res XX(X): 000–000, 2019—To provide strength and conditioning coaches a practical and evidence-based test for repeated-sprint ability (RSA) in rugby union players, this study assessed the relative and absolute test-retest reliability of the Wales Anaerobic Test (WAT) and its position-specific association with other fitness performance indices. Thirty-four players (forwards: n = 19; backs: n = 15) of the Welsh rugby union male senior national team performed the WAT (10 × 50-m distance, 25–30 seconds of passive recovery) twice within 4 days. Time for each repetition was recorded, with the best (WATBest) and total time (WATTT) retained for analysis. Relative (intraclass correlation coefficient [ICC]) and absolute (SEM) reliability of the WAT indices were quantified. Furthermore, association (Pearson's product-moment correlations and stepwise backward elimination procedure) with other fitness performance indices (10- and 40-m sprinting times, 30-15 intermittent fitness test [30-15IFT] and the Yo-Yo intermittent recovery test level 2 [YYIR2]) was investigated. Pooled values revealed “moderate” to “high” ICCs for WATBest (ICC = 0.89, p = 0.626) and WATTT (ICC = 0.95, p = 0.342). Good test sensitivity was reported for forwards and backs' WATTT (p > 0.101). Both WATBest and WATTT correlated with 10-m and 40-m sprinting times (r > 0.69, p < 0.001) as well as with 30-15IFT (r < −0.77, p < 0.001) and YYIR2 (r < −0.68, p < 0.001) for pooled values. The WAT proved to be a reliable and sensitive test to assess the rugby union specific RSA-related fitness of international players.
Adam Beard; John Ashby; Ryan Chambers; Grégoire P. Millet; Franck Brocherie. Wales Anaerobic Test. Journal of Strength and Conditioning Research 2019, Publish Ah, 1 .
AMA StyleAdam Beard, John Ashby, Ryan Chambers, Grégoire P. Millet, Franck Brocherie. Wales Anaerobic Test. Journal of Strength and Conditioning Research. 2019; Publish Ah ():1.
Chicago/Turabian StyleAdam Beard; John Ashby; Ryan Chambers; Grégoire P. Millet; Franck Brocherie. 2019. "Wales Anaerobic Test." Journal of Strength and Conditioning Research Publish Ah, no. : 1.
The aims of this study were to ensure that the skating velocity describes a mono-exponential function in order to determine the reliability of radar-derived profiling results from skating sprint accelerations applying sprint running force-velocity assessment approach. Eleven young highly-trained female ice hockey players performed two 40-m skating sprints on two separate days to evaluate inter-trial and test-retest reliability. The velocity-time data recorded by a radar device was used to calculate the kinetics variables of the skating sprint acceleration: maximal theoretical force (F0), maximal theoretical velocity (V0), maximal theoretical power (Pmax) and the slope of the linear force-velocity relationship (SFV). SFV and SFVrel variables (the slope of the linear relationship between horizontal force relative to body mass and velocity) demonstrated 'low' to 'moderate' intra-class correlation coefficients (ICC). All other variables revealed 'acceptable' inter-trial and test-retest reliability (ICC ≥ 0.75 and coefficient of variation [CV] ≤ 10%). Furthermore, test-retest reliability (ICC and CV) and sensitivity [Standard Error of Measurement (SEMs) ≤ Small Worthwhile Change (SWCs)] were higher when averaging the two trials compared to the best trial (40-m split time) only. These findings offer a promising and simple method to monitor training-induced changes in macroscopic mechanical variables of ice hockey skating performance.
Jérome Perez; Gaël Guilhem; Franck Brocherie. Reliability of the force-velocity-power variables during ice hockey sprint acceleration. Sports Biomechanics 2019, 1 -15.
AMA StyleJérome Perez, Gaël Guilhem, Franck Brocherie. Reliability of the force-velocity-power variables during ice hockey sprint acceleration. Sports Biomechanics. 2019; ():1-15.
Chicago/Turabian StyleJérome Perez; Gaël Guilhem; Franck Brocherie. 2019. "Reliability of the force-velocity-power variables during ice hockey sprint acceleration." Sports Biomechanics , no. : 1-15.
Purpose: To investigate the effects of repeated-sprint training in hypoxia vs in normoxia on world-level male rugby union players’ repeated-sprint ability (RSA) during an international competition period. Methods: A total of 19 players belonging to an international rugby union senior male national team performed 4 sessions of cycling repeated sprints (consisting of 3 × eight 10-s sprints with 20 s passive recovery) either in normobaric hypoxia (RSH, 3000 m; n = 10) or in normoxia (RSN, 300 m; n = 9) over a 2-wk period. Before and after the training intervention, RSA was evaluated using a cycling repeated-sprint test (6 × 10-s maximal sprint and 20-s passive recovery) performed in normoxia. Results: Significant interaction effects (all P < .05, ) between condition and time were found for RSA-related parameters. Compared with Pre, maximal power significantly improved at Post in RSH (12.84 [0.83] vs 13.63 [1.03] W·kg−1, P < .01, ) but not in RSN (13.17 [0.89] vs 13.00 [1.01] W·kg−1, P = .45, ). Mean power was also significantly enhanced from Pre to Post in RSH (11.15 [0.58] vs 11.86 [0.63] W·kg−1, P < .001, ), whereas it remained unchanged in RSN (11.54 [0.61] vs 11.75 [0.65] W·kg−1, P = .23, ). Conclusion: As few as 4 dedicated specific RSH sessions were beneficial to enhance repeated power production in world-level rugby union players. Although the improvement from RSA to game behavior remains unclear, this finding appears to be of practical relevance as only a short preparation window is available prior to international rugby union games.
Adam Beard; John Ashby; Ryan Chambers; Franck Brocherie; Grégoire P. Millet. Repeated-Sprint Training in Hypoxia in International Rugby Union Players. International Journal of Sports Physiology and Performance 2019, 14, 850 -854.
AMA StyleAdam Beard, John Ashby, Ryan Chambers, Franck Brocherie, Grégoire P. Millet. Repeated-Sprint Training in Hypoxia in International Rugby Union Players. International Journal of Sports Physiology and Performance. 2019; 14 (6):850-854.
Chicago/Turabian StyleAdam Beard; John Ashby; Ryan Chambers; Franck Brocherie; Grégoire P. Millet. 2019. "Repeated-Sprint Training in Hypoxia in International Rugby Union Players." International Journal of Sports Physiology and Performance 14, no. 6: 850-854.
This study investigated the effects of upper-body repeated-sprint training in hypoxia vs. in normoxia on world-level male rugby union players' repeated-sprint ability (RSA) during an international competition period. Thirty-six players belonging to an international rugby union male national team performed over a 2-week period four sessions of double poling repeated-sprints (consisting of 3 × eight 10-s sprints with 20-s passive recovery) either in normobaric hypoxia (RSH, simulated altitude 3000 m, n = 18) or in normoxia (RSN, 300 m; n = 18). At pre- and post-training intervention, RSA was evaluated using a double-poling repeated-sprint test (6 × 10-s maximal sprint with 20-s passive recovery) performed in normoxia. Significant interaction effects (P < 0.05) between condition and time were found for RSA-related parameters. Compared to Pre-, peak power significantly improved at post- in RSH (423 ± 52 vs. 465 ± 69 W, P = 0.002, η²=0.12) but not in RSN (395 ± 65 vs. 397 ± 57 W). Averaged mean power was also significantly enhanced from pre- to post-intervention in RSH (351 ± 41 vs. 388 ± 53 W, P < 0.001, η²=0.15), while it remained unchanged in RSN (327 ± 49 vs. 327 ± 43 W). No significant change in sprint decrement (P = 0.151, η² = 0.02) was observed in RSH (-17 ± 2% vs. -16 ± 3%) nor RSN (-17 ± 2% vs. -18 ± 4%). This study showed that only four upper-body RSH sessions were beneficial in enhancing repeated power production in international rugby union players. Although the improvement from RSA to game behaviour remains unclear, this finding appears of practical relevance since only a short preparation window is available prior to international games.
Adam Beard; John Ashby; Mark Kilgallon; Franck Brocherie; Grégoire P. Millet. Upper-body repeated-sprint training in hypoxia in international rugby union players. European Journal of Sport Science 2019, 19, 1175 -1183.
AMA StyleAdam Beard, John Ashby, Mark Kilgallon, Franck Brocherie, Grégoire P. Millet. Upper-body repeated-sprint training in hypoxia in international rugby union players. European Journal of Sport Science. 2019; 19 (9):1175-1183.
Chicago/Turabian StyleAdam Beard; John Ashby; Mark Kilgallon; Franck Brocherie; Grégoire P. Millet. 2019. "Upper-body repeated-sprint training in hypoxia in international rugby union players." European Journal of Sport Science 19, no. 9: 1175-1183.
Purpose: To evaluate the effect of multiple sets of repeated-sprint-ability (RSA)-induced fatigue on subsequent passing-skill performance in field hockey players. Methods: A total of 10 elite U-21 (under-21) male field hockey players performed 5 sets of a combination of RSA test (6 × 20 m, 20 s of passive recovery) followed by a 1-min passing-skill test (passing reception with subsequent passes at a predesigned target). Data on fastest sprint time and cumulated sprint time for RSA test; total number of balls played, targeted, and passing accuracy (number of balls targeted/total number of balls played) for passing-skill test; heart rate (HR), blood lactate concentration (BLa), and rating of perceived exertion (RPE) were collected throughout the protocol. Results: RSA performance was significantly impaired from set 1 to set 5 (fastest sprint time +4.1%, P < .001; cumulated sprint time +2.3%, P < .01). For a similar average number of balls played (12.8 [1.4]) during each set, number of balls targeted (−1.7%, P < .05) and passing accuracy (−3.1%, P < .05) decreased up to the third set before reimproving over the last 2 sets. Psychophysiological responses (HR, BLa, and RPE) progressively increased (P < .05) toward protocol cessation. The decrease in passing accuracy with increasing RSA cumulated sprint time was fitted to a 2nd-order polynomial function (r2 = .94, P < .05). Conclusion: Multiple-set RSA-induced fatigue was accompanied by passing-skill adjustment variation, suggesting a complex interaction between physiological and psychological/cognitive function to preserve passing skill under fatigued condition.
Enzo Hollville; Vincent Le Croller; Yoshihiro Hirasawa; Rémi Husson; Giuseppe Rabita; Franck Brocherie. Effect of Prior Fatiguing Sport-Specific Exercise on Field Hockey Passing Ability. International Journal of Sports Physiology and Performance 2018, 13, 1324 -1330.
AMA StyleEnzo Hollville, Vincent Le Croller, Yoshihiro Hirasawa, Rémi Husson, Giuseppe Rabita, Franck Brocherie. Effect of Prior Fatiguing Sport-Specific Exercise on Field Hockey Passing Ability. International Journal of Sports Physiology and Performance. 2018; 13 (10):1324-1330.
Chicago/Turabian StyleEnzo Hollville; Vincent Le Croller; Yoshihiro Hirasawa; Rémi Husson; Giuseppe Rabita; Franck Brocherie. 2018. "Effect of Prior Fatiguing Sport-Specific Exercise on Field Hockey Passing Ability." International Journal of Sports Physiology and Performance 13, no. 10: 1324-1330.
Franck Brocherie; Grégoire P. Millet. “Live High-Train Low” Paradigm: Moving the Debate Forward. Exercise and Sport Sciences Reviews 2018, 46, 271 -271.
AMA StyleFranck Brocherie, Grégoire P. Millet. “Live High-Train Low” Paradigm: Moving the Debate Forward. Exercise and Sport Sciences Reviews. 2018; 46 (4):271-271.
Chicago/Turabian StyleFranck Brocherie; Grégoire P. Millet. 2018. "“Live High-Train Low” Paradigm: Moving the Debate Forward." Exercise and Sport Sciences Reviews 46, no. 4: 271-271.