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Elliott C.R. Hall, Sandro S. Almeida, Shane M. Heffernan, Sarah J. Lockey, Adam J. Herbert, Peter Callus, Stephen H. Day, Charles R. Pedlar, Courtney Kipps, Malcolm Collins, Yannis P. Pitsiladis, Mark A. Bennett, Liam P. Kilduff, Georgina K. Stebbings, Robert M. Erskine, and Alun G. Williams

Purpose: Genetic polymorphisms have been associated with the adaptation to training in maximal oxygen uptake (V˙O2max). However, the genotype distribution of selected polymorphisms in athletic cohorts is unknown, with their influence on performance characteristics also undetermined. This study investigated whether the genotype distributions of 3 polymorphisms previously associated with V˙O2max training adaptation are associated with elite athlete status and performance characteristics in runners and rugby athletes, competitors for whom aerobic metabolism is important. Methods: Genomic DNA was collected from 732 men including 165 long-distance runners, 212 elite rugby union athletes, and 355 nonathletes. Genotype and allele frequencies of PRDM1 rs10499043 C/T, GRIN3A rs1535628 G/A, and KCNH8 rs4973706 T/C were compared between athletes and nonathletes. Personal-best marathon times in runners, as well as in-game performance variables and playing position, of rugby athletes were analyzed according to genotype. Results: Runners with PRDM1 T alleles recorded marathon times ∼3 minutes faster than CC homozygotes (02:27:55 [00:07:32] h vs 02:31:03 [00:08:24] h, P = .023). Rugby athletes had 1.57 times greater odds of possessing the KCNH8 TT genotype than nonathletes (65.5% vs 54.7%, χ 2 = 6.494, P = .013). No other associations were identified. Conclusions: This study is the first to demonstrate that polymorphisms previously associated with V˙O2max training adaptations in nonathletes are also associated with marathon performance (PRDM1) and elite rugby union status (KCNH8). The genotypes and alleles previously associated with superior endurance-training adaptation appear to be advantageous in long-distance running and achieving elite status in rugby union.

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Alexandru Nicolae Ungureanu, Corrado Lupo, Gennaro Boccia, and Paolo Riccardo Brustio

Purpose: The primary aim of this study was to evaluate whether the internal (session rating of perceived exertion [sRPE] and Edwards heart-rate-based method) and external training load (jumps) affect the presession well-being perception on the day after (ie, +22 h), according to age and tactical position, in elite (ie, Serie A2) female volleyball training. Methods: Ten female elite volleyball players (age = 23 [4] y, height = 1.82 [0.04] m, body mass = 73.2 [4.9] kg) had their heart rate monitored during 13 team (115 individual) training sessions (duration: 101 [8] min). Mixed-effect models were applied to evaluate whether sRPE, Edwards method, and jumps were correlated (P ≤ .05) to Hooper index factors (ie, perceived sleep quality/disorders, stress level, fatigue, and delayed-onset muscle soreness) in relation to age and tactical position (ie, hitters, central blockers, opposites, and setters). Results: The results showed a direct relationship between sRPE (P < .001) and presession well-being perception 22 hours apart, whereas the relationship was the inverse for Edwards method internal training load. Age, as well as the performed jumps, did not affect the well-being perception of the day after. Finally, central blockers experienced a higher delayed-onset muscle soreness than hitters (P = .003). Conclusions: Findings indicated that female volleyball players’ internal training load influences the pretraining well-being status on the day after (+ 22 h). Therefore, coaches can benefit from this information to accurately implement periodization in a short-term perspective and to properly adopt recovery strategies in relation to the players’ well-being status.

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Christian J. Cook, Blair T. Crewther, Liam P. Kilduff, Linda L. Agnew, Phillip Fourie, and Benjamin G. Serpell

Purpose: To establish if training volume was associated with androgen baselines and androgen responsiveness to acute exercise. Methods: During a “high-volume” training phase, 28 cyclists (14 men and 14 women) undertook oxygen-uptake and maximal-work-capacity testing. Two days later, they completed a repeat-sprint protocol, which was repeated 3 weeks later during a “low-volume” phase. Blood and saliva samples were collected before and after (+5 and +60 min) the repeat-sprint protocol. Blood was assayed for total testosterone (TT), free testosterone (FT), and dihydrotestosterone (DHT) and saliva, for testosterone and DHT. Results: Pretrial TT, FT, and DHT concentration was greater for males (P < .001, large effect size differences), and in both genders TT, DHT, and saliva for DHT was higher during high-volume loading (moderate to large effect size). Area-under-the-curve analysis revealed larger TT, FT, and DHT responses to the repeat-sprint protocol among females, and high-volume training was linked to larger TT, DHT, and saliva for DHT responses (moderate to large effect size). Baseline TT and FT correlated with oxygen uptake and work capacity in both genders (P < .05). Conclusion: DHT showed no acute performance correlation but was responsive to volume of training, particularly in females. This work informs on timelines and relationships of androgenic biomarkers in males and females across different training loads, adding to the complexity that should be considered in interpretation thereof. The authors speculate that testosterone may impact acute performance via behavioral mechanisms of motivation and attention; DHT, via training volume-induced androgenic promotion, may facilitate long-term adaptive changes, especially for females.

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Ciaran O’Grady, Louis Passfield, and James G. Hopker

Purpose: Rating of perceived exertion (RPE) as a training-intensity prescription has been extensively used by athletes and coaches. However, individual variability in the physiological response to exercise prescribed using RPE has not been investigated. Methods: Twenty well-trained competitive cyclists (male = 18, female = 2, maximum oxygen consumption =55.07 [11.06] mL·kg−1·min−1) completed 3 exercise trials each consisting of 9 randomized self-paced exercise bouts of either 1, 4, or 8 minutes at RPEs of 9, 13, and 17. Within-athlete variability (WAV) and between-athletes variability (BAV) in power and physiological responses were calculated using the coefficient of variation. Total variability was calculated as the ratio of WAV to BAV. Results: Increased RPEs were associated with higher power, heart rate, work, volume of expired oxygen (VO2), volume of expired carbon dioxide (VCO2), minute ventilation (V E), deoxyhemoglobin (ΔHHb) (P < .001), and lower tissue saturation index (ΔTSI%) and ΔO2Hb (oxyhaemoglobin; P < .001). At an RPE of 9, shorter durations resulted in lower VO2 (P < .05) and decreased ΔTSI%, and the ΔHHb increased as the duration increased (P < .05). At an RPE of 13, shorter durations resulted in lower VO2, V E, and percentage of maximum oxygen consumption (P < .001), as well as higher power, heart rate, ΔHHb (P < .001), and ΔTSI% (P < .05). At an RPE of 17, power (P < .001) and ΔTSI% (P < .05) increased as duration decreased. As intensity and duration increased, WAV and BAV in power, work, heart rate, VO2, VCO2, and VE decreased, and WAV and BAV in near-infrared spectroscopy increased. Conclusions: Self-paced intensity prescriptions of high effort and long duration result in the greatest consistency on both a within- and between-athletes basis.

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Samantha M. Ross, Kathleen McCarty, Bridgette M. Schram, and Layne Case

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Kyle Pushkarenko, Janice Causgrove Dunn, and Donna L. Goodwin

Countering the declining physical activity patterns of children labeled with autism spectrum disorder (ASD) has gained considerable research attention given its impact on health and quality of life. The purpose of this study was to explore how parents of children labeled with ASD understand the concept of physical literacy, based on their children’s participation in community-based physical activity programs. Using interpretive phenomenological analysis, six mothers of children labeled with ASD participated in one-on-one semistructured interviews. The conceptual framework of ecological systems theory supported the rationale for the study purpose, provided structure for the interview guide, and offered a reflexive context for interpretation. Four themes were generated from the thematic analysis: From embodied movement to normative skill expectations, Be flexible, not rigid, Systematic exclusion, and Valuable? . . . Absolutely! Despite experiences of marginalization, exclusion, and trauma within physical activity programs, mothers valued physical literacy development for their children given the positive outcomes of increasing family connections, engagement with peers, and enhanced wellness.

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Amanda Young, Seán Healy, Lisa Silliman-French, and Ali Brian

To inform the development of scalable and sustainable fundamental motor skill interventions for children with Down syndrome, this study examined the feasibility and preliminary effectiveness of Project Skill Intervention Implemented by Parents (Project SKIP), a web-based, parent-mediated intervention intended to improve ball skills among children with Down syndrome. Twenty-four families enrolled in the study (including 13 boys and 11 girls; M age = 4.92). Fourteen children were assigned to an experimental group and participated in the 6-week intervention, and 10 children served as the inactive comparison group. The Test of Gross Motor Development-3 was administered preintervention and postintervention. In addition, parents of children in the experimental group completed a postintervention survey to assess their perceptions of Project SKIP. Following the intervention, there was a significant improvement in ball skills (p = .023, d = 0.86) for children in the experimental group, whereas the comparison group did not show significant improvement. Moreover, parents perceived Project SKIP to be feasible and effective; all parents reported being satisfied with their overall experience in the program, and 11 parents indicated that their child’s fundamental motor skills were positively influenced by the intervention. Engagement was high, with the majority of parents (n = 8, 57%) interacting with Project SKIP content three to four times a week.

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Benjamin A. McKay, Jace A. Delaney, Andrew Simpkin, Theresa Larkin, Andrew Murray, Charles R. Pedlar, Nathan A. Lewis, and John A. Sampson

Purpose: To assess associations between a free oxygen radical test (FORT), free oxygen radical defense test (FORD), oxidative stress index, urinary cortisol, countermovement jump (CMJ), and subjective wellness in American college football. Methods: Twenty-three male student athlete American college football players were assessed over 10 weeks: off-season conditioning (3 wk), preseason camp (4 wk), and in season (3 wk). Assessments included a once-weekly FORT and FORD blood sample, urinary cortisol sample, CMJ assessment including flight time, reactive strength index modified and concentric impulse, and a daily subjective wellness questionnaire. Linear mixed models analyzed the effect of a 2 within-subject SD change in the predictor variable on the dependent variable. The effects were interpreted using magnitude-based inference and are presented as standardized effect size (ES) ± 90% confidence intervals. Results: Small negative associations were observed between FORT–flight time, FORT–fatigue, FORT–soreness (ES range = −0.30 to −0.48), FORD–sleep (ES = 0.42 ± 0.29), and oxidative stress index soreness (ES = 0.56 ± 0.29). Small positive associations were observed between FORT–cortisol (ES = 0.36 ± 0.35), FORD–flight time, FORD reactive strength index modified and FORD–soreness (0.37–0.41), oxidative stress index concentric impulse (ES = 0.37 ± 0.28), and with soreness–concentric impulse, soreness–flight time, and soreness reactive strength index modified (0.33–0.59). Moderate positive associations were observed between cortisol–concentric impulse and cortisol–sleep (0.57–0.60). Conclusion:FORT/FORD was associated with CMJ variables and subjective wellness. Greater amounts of subjective soreness were associated with decreased CMJ performance, increased FORT and cortisol, and decreased FORD.

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Adam Field, Liam D. Harper, Bryna C.R. Chrismas, Peter M. Fowler, Alan McCall, Darren J. Paul, Karim Chamari, and Lee Taylor

Purpose: To survey soccer practitioners’ recovery strategy: (1) use, (2) perceived effectiveness, and (3) factors influencing their implementation in professional soccer. Methods: A cross-sectional convenience sample of professional soccer club/confederation practitioners completed a web-based survey (April to July 2020). Pearson chi-square and Fisher exact tests with Cramer V (φ − c) assessed relationships and their strength, respectively, between the perceived effectiveness and frequency of strategy use. Results: A total of 80 soccer practitioners (13 countries) completed the survey. The 3 most important recovery objectives were “alleviating muscle damage/fatigue,” “minimizing injury risk,” and “performance optimization.” The most frequently used strategies were active recovery, structured recovery day, extra rest day, massage, cold-water therapy, and carbohydrate provision (predominantly on match day and match day + 1). Relationships were identified between perceived effectiveness and frequency of strategy use for sleep medication (P < .001, φ − c = 0.48), carbohydrate provision (P = .007, φ − c = 0.60), protein provision (P = .007, φ − c = 0.63), an extra rest day (P < .001, φ − c = 0.56), and a structured recovery day (P = .049, φ − c = 0.50). Conclusions: The study demonstrates that professional soccer practitioners have a range of objectives geared toward enhancing player recovery. A disconnect is apparent between the perceived effectiveness of many recovery strategies and their frequency of use in an applied setting. Novel data indicate that strategies are most frequently employed around match day. Challenges to strategy adoption are mainly competing disciplinary interests and resource limitations. Researchers and practitioners should liaise to ensure that the complexities involved with operating in an applied environment are elucidated and apposite study designs are adopted, in turn, facilitating the use of practically effective and compatible recovery modalities.