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Andrew M. Holwerda, Jorn Trommelen, Imre W.K. Kouw, Joan M. Senden, Joy P.B. Goessens, Janneau van Kranenburg, Annemie P. Gijsen, Lex B. Verdijk, and Luc J.C. van Loon

Protein ingestion and exercise stimulate myofibrillar protein synthesis rates. When combined, exercise further increases the postprandial rise in myofibrillar protein synthesis rates. It remains unclear whether protein ingestion with or without exercise also stimulates muscle connective tissue protein synthesis rates. The authors assessed the impact of presleep protein ingestion on overnight muscle connective tissue protein synthesis rates at rest and during recovery from resistance-type exercise in older men. Thirty-six healthy, older men were randomly assigned to ingest 40 g intrinsically L-[1-13C]-phenylalanine and L-[1-13C]-leucine-labeled casein protein (PRO, n = 12) or a nonprotein placebo (PLA, n = 12) before going to sleep. A third group performed a single bout of resistance-type exercise in the evening before ingesting 40 g intrinsically-labeled casein protein prior to sleep (EX+PRO, n = 12). Continuous intravenous infusions of L-[ring- 2H5]-phenylalanine and L-[1-13C]-leucine were applied with blood and muscle tissue samples collected throughout overnight sleep. Presleep protein ingestion did not increase muscle connective tissue protein synthesis rates (0.049 ± 0.013 vs. 0.060 ± 0.024%/hr in PLA and PRO, respectively; p = .73). Exercise plus protein ingestion resulted in greater overnight muscle connective tissue protein synthesis rates (0.095 ± 0.022%/hr) when compared with PLA and PRO (p < .01). Exercise increased the incorporation of dietary protein-derived amino acids into muscle connective tissue protein (0.036 ± 0.013 vs. 0.054 ± 0.009 mole percent excess in PRO vs. EX+PRO, respectively; p < .01). In conclusion, resistance-type exercise plus presleep protein ingestion increases overnight muscle connective tissue protein synthesis rates in older men. Exercise enhances the utilization of dietary protein-derived amino acids as precursors for de novo muscle connective tissue protein synthesis during overnight sleep.

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Nick Dobbin, Anthony Atherton, and Colin Hill

Purpose: To determine if small-sided games (SSGs) could be designed to target specific task loads using the National Aeronautics and Space Administration task load index as well as reporting the influence of the physical and technical demands. Methods: Using a within-session, repeated-measures design, 26 junior rugby league players completed 5 SSGs focused on physical, technical, temporal, cognitive, and frustration task loads. National Aeronautics and Space Administration task load index responses were evaluated after each game; the physical demands were recorded using microtechnology; and skill involvement recorded using video analysis. Results: In each SSG, the task load emphasized (eg, physical load/physical game) emerged with a higher score than the other loads and SSGs. The physical demands were lowest during the physical game (effect size = −3.11 to 3.50) and elicited greater defensive involvements (effect size = 0.12 to 3.19). The highest physical demands and attacking involvements were observed during the temporal game. Lower intensity activities were generally negatively associated with physical, performance, temporal, and total load (η 2 = −.07 to −.43) but positively associated with technical, effort, cognitive, and frustration (η 2 = .01 to .33). Distance covered in total and at higher speeds was positively associated with physical, effort, performance, total load (η 2 = .18 to .65), and negatively associated with technical, frustration, and cognitive load (η 2 = −.10 to −.36). Attacking and defensive involvements generally increased the respective task loads (η 2 = .03 to .41). Conclusion: Coaches and sport scientists can design SSGs specifically targeted at subjective task loads in a sport-specific manner and through manipulation of the physical and technical demands.

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Irineu Loturco, Lucas A. Pereira, Tomás T. Freitas, Chris Bishop, Fernando Pareja-Blanco, and Michael R. McGuigan

Purpose: To test the relationships between maximum and relative strength (MS and RS), absolute and relative peak force (PF and RPF), and strength deficit (SDef), with sprint and jump performance, and to compare these mechanical variables between elite sprinters and professional rugby union players. Methods: Thirty-five male rugby union players and 30 male sprinters performed vertical jumps, 30-m sprint, and half-squat 1-repetition maximum (1RM), where these force-related parameters were collected. Pearson correlation coefficients were used to test the relationships between the variables. An independent t test and magnitude-based inferences compared the mechanical variables between sprinters and rugby players. Results: Almost certain significant differences were observed for jump and sprint performance between groups (P < .0001). The rugby union players demonstrated a likely significant higher MS (P = .03) but a very likely lower RS (P = .007) than the sprinters. No significant differences were observed for PF between them. The sprinters exhibited an almost certain significant higher RPF than the rugby players (P < .0001). Furthermore, the rugby players demonstrated almost certain to likely significant higher SDef from 40% to 70% 1RM (P < .05) compared with the sprinters. Overall, all strength-derived parameters were significantly related to functional performance. Conclusions: Elite sprinters present higher levels of RS and RPF, lower levels of SDef, and better sprint and jump performance than professional rugby players. Relative strength-derived values (RS and RPF) and SDef are significantly associated with speed–power measures and may be used as effective and practical indicators of athletic performance.

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Marie-Pier McSween, Katie L. McMahon, Kylie Maguire, Jeff S. Coombes, Amy D. Rodriguez, Kirk I. Erickson, and David A. Copland

Recent studies show positive effects of acute exercise on language learning in young adults with lower baseline learning abilities; however, this is yet to be investigated in older adults. This study investigated the acute effects of different exercise intensities on new word learning in healthy older adults with lower and higher baseline learning abilities. Sixty older adults (mean age = 66.4 (4.6); 43 females) performed either a single bout of stretching exercise, moderate-intensity continuous exercise, or high-intensity interval exercise followed by a word learning task. In lower baseline learners, between-group differences were observed on immediate new word recall success, with the moderate-intensity continuous exercise group performing better than the stretching group. These findings suggest immediate benefits of moderate-intensity continuous exercise that are limited to word learning performance of older adults with lower baseline learning abilities. Further investigation into underlying mechanisms could lead to a better understanding of individual differences in responding to acute exercise.

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Pauline Manon Genin, Céline Lambert, Benjamin Larras, Bruno Pereira, Jean-François Toussaint, Julien Steven Baker, Angelo Tremblay, David Thivel, and Martine Duclos

Background: The French National Observatory for Physical Activity and Sedentary Behaviors conducted a national survey aiming to evaluate the potential effects of confinement on the population’s physical activity levels and sedentary behaviors. Methods: In close collaboration with the French Ministry of Sports and a selected expert committee, 3 different questionnaires investigating 3 subgroup populations were included in the survey: (1) children, (2) adolescents, and (3) adults. Results: Forty-two percentage of children, 58.7% of adolescents, 36.4% of adults, and 39.2% of older people had reduced physical activity levels. Particularly, active transportation and endurance practices showed a significant decrease, while domestic, muscular strengthening, and flexibility activities increased. Sitting time and screen time increased, respectively, in 36.3% and 62.0% of children, 25.5% and 69.0% in adolescents, 24.6% and 41.0% in adults, and 36.1% and 32.1% in seniors. Conclusion: The COVID-19 confinement period led to important modifications in individual movement behaviors at all ages, particularly favoring decreased physical activity and increased sedentariness. These findings suggest that the authors need to inform and encourage people to maintain and improve their physical activities and to change their sedentary time habits during postconfinement and during the period of a potential future lockdown.

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Sara Almeida, Cátia Paixão, Madalena Gomes da Silva, and Alda Marques

The objective of this study was to explore the feasibility and preliminary effectiveness of the Lifestyle-Integrated Functional Exercise for People with Dementia (LiFE4D) on health-related physical fitness, cognitive function, physical activity, and respiratory and upper limb functions. A randomized controlled pilot study was conducted (control group: usual care; experimental group: usual care and LiFE4D). The feasibility of LiFE4D was determined considering recruitment, protocol acceptability, adherence, and safety. Measures of health-related physical fitness, cognitive function, physical activity, and respiratory and upper limb functions were assessed at the baseline and 3 months. Twelve participants (8 [66.7%] female, 82 [72.2–84] years) were included, six per group. Recruitment was challenging. LiFE4D was acceptable with excellent adherence and no major adverse events. Cardiorespiratory endurance (effect size = 1.64, 95% confidence interval [CI; 0.33, 2.95]) and balance (effect size = 1.46, 95% CI [0.19, 2.73]) improved after LiFE4D. LiFE4D seems to be feasible and safe, and it shows potential to significantly improve the health-related physical fitness of people with dementia.

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Rihab Borji, Firas Zghal, Nidhal Zarrouk, Sonia Sahli, and Haithem Rebai

The authors explored neuromuscular fatigue in athletes with intellectual disability (AID) compared with sedentary individuals with intellectual disability (SID) and individuals with typical development. Force, voluntary activation level, potentiated resting twitch, and electromyography signals were assessed during isometric maximal voluntary contractions performed before and immediately after an isometric submaximal exhaustive contraction (15% isometric maximal voluntary contractions) and during recovery period. AID presented shorter time to task failure than SID (p < .05). The three groups presented similar isometric maximal voluntary contraction decline and recovery kinetic. Both groups with intellectual disability presented higher voluntary activation level and root mean square normalized to peak-to-peak M-wave amplitude declines (p < .05) compared with individuals with typical development. These declines were more pronounced in SID (p < .05) than in AID. The AID recovered their initial voluntary activation level later than controls, whereas SID did not. SID presented lower potentiated resting twitch decline compared with AID and controls with faster recovery (p < .05). AID presented attenuated central fatigue and accentuated peripheral fatigue compared with their sedentary counterparts, suggesting a neuromuscular profile close to that of individuals with typical development.

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Jacob Szeszulski, Kevin Lanza, Erin E. Dooley, Ashleigh M. Johnson, Gregory Knell, Timothy J. Walker, Derek W. Craig, Michael C. Robertson, Deborah Salvo, and Harold W. Kohl III

Background: Multiple models and frameworks exist for the measurement and classification of physical activity in adults that are applied broadly across populations but have limitations when applied to youth. The authors propose a conceptual framework specifically designed for classifying youth physical activity. Methods: The Youth Physical Activity Timing, How, and Setting (Y-PATHS) framework is a conceptualization of the when (timing), how, and where (setting) of children’s and adolescents’ physical activity patterns. The authors developed Y-PATHS using the design thinking process, which includes 3 stages: inspiration, ideation, and implementation. Results: The Y-PATHS includes 3 major components (timing, how, and setting) and 13 subcomponents. Timing subcomponents include (1) school days: in-school, (2) school days: out-of-school, and (3) nonschool days. How subcomponents include: (1) functional, (2) transportation, (3) organized, and (4) free play. Setting subcomponents include: (1) natural areas, (2) schools, (3) home, (4) recreational facilities, (5) shops and services, and (6) travel infrastructure. Conclusions: The Y-PATHS is a comprehensive classification framework that can help researchers, practitioners, and policymakers to better understand youth physical activity. Specifically, Y-PATHS can help to identify the domains of youth physical activity for surveillance and research and to inform the planning/evaluation of more comprehensive physical activity programming.

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Ralph Beneke and Renate M. Leithäuser

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Roberto Baldassarre, Cristian Ieno, Marco Bonifazi, and Maria Francesca Piacentini

Purpose: The sensation of fatigue experienced at a certain point of the race is an important factor in the regulation of pacing. The rating of perceived exertion (RPE) is considered one of the main mediators utilized by athletes to modify pacing. The aim was to analyze the relationship between pacing and RPE of elite open water swimmers during national indoor pool championships. Methods: A total of 17 elite open water swimmers (males, n = 9; females, n = 8) agreed to provide RPE every 500 m during the finals of the national championships 5-km indoor pool race. Time splits, stroke rate, and RPE were collected every 500 m. The Hazard score was calculated by multiplying the momentary RPE by the remaining fraction of the race. Athletes were placed in one of two categories: medalists or nonmedalists. For all variables, separate mixed analysis of variances (P ≤ .05) with repeated measures were used considering the splits (ie, every 500 m) as within-subjects factor and the groups (ie, medalists and nonmedalists) as between-subjects factor. Results: Average swimming speed showed a significant main effect for split for both males and females (P < .001). A significant interaction was observed between average swimming speed and groups for females (P = .032). RPE increased in both groups (P < .001) with no difference observed between groups. However, the female nonmedalists showed a disproportionate nonlinear increase in RPE (5.20 [2.31]) halfway through the event that corresponded to the point where they started significantly decreasing speed. Conclusions: The results of the present study show different pacing strategies adopted by medalists and nonmedalists despite a similar RPE.