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Graeme L. Close, Andreas M. Kasper, Neil P. Walsh, and Ronald J. Maughan

The term “food first” has been widely accepted as the preferred strategy within sport nutrition, although there is no agreed definition of this and often limited consideration of the implications. We propose that food first should mean “where practically possible, nutrient provision should come from whole foods and drinks rather than from isolated food components or dietary supplements.” There are many reasons to commend a food first strategy, including the risk of supplement contamination resulting in anti-doping violations. However, a few supplements can enhance health and/or performance, and therefore a food only approach could be inappropriate. We propose six reasons why a food only approach may not always be optimal for athletes: (a) some nutrients are difficult to obtain in sufficient quantities in the diet, or may require excessive energy intake and/or consumption of other nutrients; (b) some nutrients are abundant only in foods athletes do not eat/like; (c) the nutrient content of some foods with established ergogenic benefits is highly variable; (d) concentrated doses of some nutrients are required to correct deficiencies and/or promote immune tolerance; (e) some foods may be difficult to consume immediately before, during or immediately after exercise; and (f) tested supplements could help where there are concerns about food hygiene or contamination. In these situations, it is acceptable for the athlete to consider sports supplements providing that a comprehensive risk minimization strategy is implemented. As a consequence, it is important to stress that the correct terminology should be “food first but not always food only.”

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Kristin Sainani and Karim Chamari

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Woo-Hwi Yang, Jeong-Hyun Park, Yun-Cheol Shin, and Jun Kim

Purpose: The aim of this study was to investigate physiological responses and energetic contributions during simulated epée matches in elite fencers. Methods: Ten elite male fencers participated in simulated epée (direct elimination) matches. Simulated epée matches included 3 bouts of 3 minutes each with 1-minute rests between bouts. During these sessions, physiological variables such as mean and peak heart rate, peak and mean oxygen uptake (VO2peak and VO2mean), metabolic equivalents of task in VO2peak and VO2mean, and blood lactate concentrations (peak lactate concentration and delta blood lactate concentration) were measured. Furthermore, energetic contributions (oxidative [WOxi], glycolytic, and phosphagen) and time–motion variables were estimated. Results: Values of peak heart rate, mean heart rate, and WOxi (in percentages) were significantly higher in the second and third bouts compared with the first. VO2peak and metabolic equivalents of task in VO2peak were significantly higher in the first bout compared with the third bout. Values of delta blood lactate concentration and glycolytic contribution (in kilojoules and percentages) were significantly lower in the second and third bouts compared with the first. VO2mean and metabolic equivalents of task in VO2mean were significantly higher in the second bout compared with the third bout. Furthermore, WOxi (in kilojoules and percentage) was significantly higher in all bouts compared with phosphagen and glycolytic contributions. Low positive and negative correlations were seen between WOxi, VO2mean, sum of attacks and defense times, and the sum of time without attacks and defenses. Conclusions: Direct-elimination epée matches consist of high-intensity intermittent exercise, and the oxidative contribution is 80% to 90%. Improving aerobic conditioning may support high-intensity intermittent actions during entire epée matches in elite fencers.

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Louis Passfield, Juan M. Murias, Massimo Sacchetti, and Andrea Nicolò

Training load (TL) is a widely used concept in training prescription and monitoring and is also recognized as as an important tool for avoiding athlete injury, illness, and overtraining. With the widespread adoption of wearable devices, TL metrics are used increasingly by researchers and practitioners worldwide. Conceptually, TL was proposed as a means to quantify a dose of training and used to predict its resulting training effect. However, TL has never been validated as a measure of training dose, and there is a risk that fundamental problems related to its calculation are preventing advances in training prescription and monitoring. Specifically, we highlight recent studies from our research groups where we compare the acute performance decrement measured following a session with its TL metrics. These studies suggest that most TL metrics are not consistent with their notional training dose and that the exercise duration confounds their calculation. These studies also show that total work done is not an appropriate way to compare training interventions that differ in duration and intensity. We encourage scientists and practitioners to critically evaluate the validity of current TL metrics and suggest that new TL metrics need to be developed.

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Andrew A. Flatt and Daniel Howells

Purpose: To report the impact of long-haul travel and the Olympic tournament on heart-rate variability and subjective well-being in a rugby sevens team. Methods: Players (N = 12 men) recorded daily root mean square of successive differences (LnRMSSD) and brief subjective well-being assessments before and throughout the Olympic tournament. Following a 7-day baseline involving a tournament simulation, 2 flights were taken to Brazil (20-h travel and 4-h time gain) on day 1. Matches occurred on days 13 to 15. Undefeated, the team advanced to the gold-medal final. Team staff used a combination of proactive and reactive strategies to support training adaptations, mitigate negative effects of travel, and facilitate recovery from competition. Results: Peak LnRMSSD values from the preceding preparatory period were observed at baseline. Perceived recovery was impaired on day 1 following tournament simulation (P < .05). Lower and less stable LnRMSSD trends were observed in players within the first week following long-haul travel (P < .05), evident primarily in nonstarters (effect size = unclear to very large) versus starters (effect size = unclear). Status markers were subsequently maintained at baseline or improved prior to the tournament and were minimally affected by competition (P > .05). Changes in LnRMSSD were associated (P < .05) with changes in perceived recovery (day 14, ρ = .64) and sleep quality (day 15, ρ = .69) during the tournament. Conclusions: Attentiveness to player health and well-being throughout preparation, travel, and the Olympic tournament potentially mitigated decrements in status markers, thereby reducing potential for fatigue or stress-related performance impairment.

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Ryan T. Letter, Dan B. Dwyer, Eric J. Drinkwater, and Simon A. Feros

Purpose: This study investigated the differences between selected physical attributes and ball release speed in slower and faster male and female elite pace bowlers. Methods: Twelve physical attributes and ball release speed were retrospectively analyzed from 63 male and 31 female elite pace bowlers over the course of 5 seasons. Pace bowlers were categorized as either fast (>122.9 km/h, males and >97.8 km/h, females) or slow (<122.9 km/h, males and <97.8 km/h, females) for each sex. Differences in physical attributes between slower and faster bowling groups were compared using Cohen d effect sizes. Results: Faster pace bowlers displayed differences in isometric midthigh-pull peak force (d = 0.25, males and d = 0.68, females) and relative peak force (d = 0.62, males and d = 0.77, females). Faster male pace bowlers displayed differences in relative (d = 0.61) and absolute (d = 0.39) countermovement jump heights. Faster female pace bowlers displayed differences in 1-repetition-maximum bench-pull strength (d = 0.45) and run-of-3 performance (relative average, d = 1.22; relative best, d = 1.12; average, d = 0.49; and best, d = 0.40). Conclusions: Anaerobic dominant physical attributes appear to be important in both male and female pace bowlers. The contribution of these physical attributes to ball release speed appears to differ slightly between males and females. Lower-body strength (males and females), lower-body power (males), relative anaerobic capacities (females), and upper-body strength (females) appear to distinguish between slower and faster elite pace bowlers.

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Adrien Vachon, Nicolas Berryman, Iñigo Mujika, Jean-Baptiste Paquet, and Laurent Bosquet

Purpose:To assess the effect of a rugby-specific high-intensity interval-training (HIITRugby) protocol on the repeated high-intensity-effort ability of young elite rugby union players and to verify the influence of 2 preconditioning sequences composed either of physical contacts (ie, tackles) or of additional runs on the magnitude of improvement. Method: Fourteen players (19 [1] y; 183.5 [8.6] cm; 95.6 [15.6] kg) underwent an HIITRugby protocol, consisting of 7 supervised training sessions over 4 weeks, each session including 3 or 4 sets of 1 to 2 minutes with 1-minute recovery. Prior to HIITRugby training, players underwent a preconditioning contact sequence or a preconditioning running sequence, to assess their influence on subsequent interval-training sessions. Results: The overall group showed a moderate improvement in total sprint time, sprints ≥90% of the best, and 20-m sprint (−3.91% [2.68%], P = .0002; 74.6% [123.7%], P = .012; −3.22% [3.13%], P = .003, respectively) and a large improvement in percentage decrement (−23.1% [20.5%], P = .005) following the 4-week training block. Relative improvements were similar between groups in total sprint time, 20-m sprint, and perceived difficulty, but the preconditioning running-sequence group exhibited a larger magnitude of gains in percentage decrement (−28.6% [20.2%] vs −17.6% [20.7%]; effect size = −1.01 vs −0.73). Conclusion: An HIITRugby training block was effective to improve repeated high-intensity-effort ability. A preconditioning contact sequence prior to HIITRugby can reduce subsequent long-interval running activity, which may attenuate the improvement of repeated high-intensity-effort indices related to the aerobic system.

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Danilo V. Tolusso, Ward C. Dobbs, Haley V. MacDonald, Lee J. Winchester, C. Matthew Laurent, Michael V. Fedewa, and Michael R. Esco

Although a variety of tools to monitor recovery have been developed, many are impractical for daily use due to cost, time, and challenges with interpretation. The Perceived Recovery Status (PRS) scale was recently developed as an expeditious, noninvasive tool to assess recovery status. While PRS has been strongly associated with repeated sprinting performance, a paucity of research exists relating PRS and performance recovery following resistance exercise. Purpose: The purpose of this study was to evaluate the sensitivity of PRS as a subjective marker of recovery up to 72 hours after a high-volume back-squat protocol. Methods: Eleven resistance-trained men reported to the laboratory on 5 separate occasions (1 familiarization session and 4 testing sessions). The first testing session was considered the baseline session and consisted of a nonfatiguing performance assessment (ie, countermovement jumps and back squats) and a fatiguing back-squat protocol of 8 sets of 10 at 70% 1-repetition maximum separated by 2 minutes of recovery. Participants returned 24, 48, and 72 hours following baseline to provide a PRS rating and complete the performance assessment. Results: Repeated-measures correlations revealed strong associations between PRS countermovement jump (r = .84) and mean bar velocity (r = .80) (both P < .001). Conclusions: The current findings suggest that PRS can be used as a method to effectively assess daily recovery following a fatiguing bout of resistance exercise. Practitioners are cautioned that the relationship between PRS and performance recovery is individualized, and equivalent PRS scores between individuals are not indicative of similar recovery.

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Lorcan S. Daly, Ciarán Ó Catháin, and David T. Kelly

Purpose: This study investigated the influence of components of fitness on measures of performance attenuation and recovery following Gaelic football match play. Methods: Measurements of players’ anthropometric characteristics, body composition, running speed, lower-body strength and power, blood lactate concentrations, running economy, and maximal aerobic capacity (V˙O2max) were taken over 2 separate days 1 week prior to a competitive match. Creatine kinase, countermovement jump height, drop jump height, contact time, reactive strength index, and perceptual responses were tested prematch, at full time, 24 hours postmatch, and 48 hours postmatch. Results: Multiple components of fitness were associated with reduced performance attenuation and improved recovery responses (adjusted R 2 = 9.8%–27.6%; P < .05). Players were divided into higher-standard and lower-standard V˙O2max (higher standard: 57.4 [4.2] mL·kg−1·min−1; lower standard: 45.3 [3.8] mL·kg−1·min−1) and relative squat (higher standard: 1.46 [0.11] 1-repetition-maximum kg·body mass−1; lower standard: 1.20 [0.08] 1-repetition-maximum kg·body mass−1) groups. After adjusting for prematch baseline differences, there were significant differences between V˙O2max groups in drop jump height at 24 hours postmatch (ηp2=.078.154; P < .05) and countermovement jump height at 48 hours postmatch (ηp2=.134; P < .05), where the lower-standard group displayed larger decrements. In addition, there were significant differences between relative squat groups at all postmatch time points in contact time (ηp2=.156.194; P < .05) and reactive strength index (ηp2=.127.223; P < .05) and in perceptual responses at 24 hours postmatch (ηp2=.152; P < .05), where the lower-standard group expressed larger decrements. Conclusion: Coaches should prioritize the development of aerobic capacity and neuromuscular function as an effective method of reducing performance attenuation and enhancing recovery kinetics in Gaelic football.

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Gyan A. Wijekulasuriya, Vernon G. Coffey, Luke Badham, Fergus O’Connor, Avish P. Sharma, and Gregory R. Cox

Purpose: The effect of acetaminophen (ACT, also known as paracetamol) on endurance performance in hot and humid conditions has been shown previously in recreationally active populations. The aim of this study was to determine the effect of ACT on physiological and perceptual variables during steady-state and time-trial cycling performance of trained triathletes in hot and humid conditions. Methods: In a randomized, double-blind crossover design, 11 triathletes completed ∼60 minutes steady-state cycling at 63% peak power output followed by a time trial (7 kJ·kg body mass−1, ∼30 min) in hot and humid conditions (∼30°C, ∼69% relative humidity) 60 minutes after consuming either 20 mg·kg body mass−1 ACT or a color-matched placebo. Time-trial completion time, gastrointestinal temperature, skin temperature, thermal sensation, thermal comfort, rating of perceived exertion, and fluid balance were recorded throughout each session. Results: There was no difference in performance in the ACT trial compared with placebo (P = .086, d = 0.57), nor were there differences in gastrointestinal and skin temperature, thermal sensation and comfort, or fluid balance between trials. Conclusion: In conclusion, there was no effect of ACT (20 mg·kg body mass−1) ingestion on physiology, perception, and performance of trained triathletes in hot and humid conditions, and existing precooling and percooling strategies appear to be more appropriate for endurance cycling performance in the heat.