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Ben T. Stephenson, Christof A. Leicht, Keith Tolfrey and Victoria L. Goosey-Tolfrey

Purpose: In able-bodied athletes, several hormonal, immunological, and psychological parameters are commonly assessed in response to intensified training due to their potential relationship to acute fatigue and training/nontraining stress. This has yet to be studied in Paralympic athletes. Methods: A total of 10 elite paratriathletes were studied for 5 wk around a 14-d overseas training camp whereby training load was 137% of precamp levels. Athletes provided 6 saliva samples (1 precamp, 4 during camp, and 1 postcamp) for cortisol, testosterone, and secretory immunoglobulin A; weekly psychological questionnaires (Profile of Mood State [POMS] and Recovery-Stress Questionnaire for Athletes [RESTQ-Sport]); and daily resting heart rate and subjective wellness measures including sleep quality and quantity. Results: There was no significant change in salivary cortisol, testosterone, cortisol:testosterone ratio, or secretory immunoglobulin A during intensified training (P ≥ .090). Likewise, there was no meaningful change in resting heart rate or subjective wellness measures (P ≥ .079). Subjective sleep quality and quantity increased during intensified training (P ≤ .003). There was no significant effect on any POMS subscale other than lower anger (P = .049), whereas there was greater general recovery and lower sport and general stress from RESTQ-Sport (P ≤ .015). Conclusions: There was little to no change in parameters commonly associated with the fatigued state, which may relate to the training-camp setting minimizing external life stresses and the careful management of training loads from coaches. This is the first evidence of such responses in Paralympic athletes.

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Aaron T. Scanlan, Vincent J. Dalbo, Daniele Conte, Emilija Stojanović, Nenad Stojiljković, Ratko Stanković, Vladimir Antić and Zoran Milanović

Purpose: To examine the effect of caffeine supplementation on dribbling speed in elite female and male basketball players. Methods: A double-blind, counterbalanced, randomized, crossover design was used. Elite basketball players (N = 21; 10 female, 11 male; age 18.3 [3.3] y) completed placebo (3 mg·kg−1 of body mass of dextrose) and caffeine (3 mg·kg−1 of body mass) trials 1 wk apart during the in-season phase. During each trial, players completed 20-m linear sprints with and without dribbling a basketball. Performance times were recorded at 5-, 10-, and 20-m splits. Dribbling speed was measured using traditional (total performance time) and novel (dribble deficit) methods. Dribble deficit isolates the added time taken to complete a task when dribbling compared with a nondribbling version of the same task. Comparisons between placebo and caffeine conditions were conducted at group and individual levels. Results: Nonsignificant (P > .05), trivial to small (effect size = 0.04–0.42) differences in dribbling speed were observed between conditions. The majority (20 out of 21) of players were classified as nonresponders to caffeine, with 1 player identified as a negative responder using dribble-deficit measures. Conclusions: Results indicate that caffeine offers no ergogenic benefit to dribbling speed in elite basketball players. The negative response to caffeine in 1 player indicates that caffeine supplementation may be detrimental to dribbling speed in specific cases and emphasizes the need for individualized analyses in nutrition-based sport-science research.

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Michael J. Davies, Bradley Clark, Laura A. Garvican-Lewis, Marijke Welvaert, Christopher J. Gore and Kevin G. Thompson

Purpose: To determine if a series of trials with fraction of inspired oxygen (FiO2) content deception could improve 4000-m cycling time-trial (TT) performance. Methods: A total of 15 trained male cyclists (mean [SD] body mass 74.2 [8.0] kg, peak oxygen uptake 62 [6] mL·kg−1·min−1) completed six 4000-m cycling TTs in a semirandomized order. After a familiarization TT, cyclists were informed in 2 initial trials they were inspiring normoxic air (NORM, FiO2 0.21); however, in 1 trial (deception condition), they inspired hyperoxic air (NORM-DEC, FiO2 0.36). During 2 subsequent TTs, cyclists were informed they were inspiring hyperoxic air (HYPER, FiO2 0.36), but in 1 trial, normoxic air was inspired (HYPER-DEC). In the final TT (NORM-INFORM), the deception was revealed and cyclists were asked to reproduce their best TT performance while inspiring normoxic air. Results: Greater power output and faster performances occurred when cyclists inspired hyperoxic air in both truthful (HYPER) and deceptive (NORM-DEC) trials than NORM (P < .001). However, performance only improved in NORM-INFORM (377 W; 95% confidence interval [CI] 325–429) vs NORM (352 W; 95% CI 299–404; P < .001) when participants (n = 4) completed the trials in the following order: NORM-DEC, NORM, HYPER-DEC, HYPER. Conclusions: Cycling performance improved with acute exposure to hyperoxia. Mechanisms for the improvement were likely physiological; however, improvement in a deception trial suggests an additional placebo effect. Finally, a particular sequence of oxygen deception trials may have built psychophysiological belief in cyclists such that performance improved in a subsequent normoxic trial.

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Bruno Marrier, Alexandre Durguerian, Julien Robineau, Mounir Chennaoui, Fabien Sauvet, Aurélie Servonnet, Julien Piscione, Bertrand Mathieu, Alexis Peeters, Mathieu Lacome, Jean-Benoit Morin and Yann Le Meur

Purpose: Preconditioning strategies are considered opportunities to optimize performance on competition day. Although investigations conducted in rugby players on the effects of a morning preconditioning session have been done, additional work is warranted. The aim of this study was to monitor changes in physical and psychophysiological indicators among international Rugby-7s players after a priming exercise. Methods: In a randomized crossover design, 14 under-18 international Rugby-7s players completed, at 8:00 AM, a preconditioning session consisting of a warm-up followed by small-sided games, accelerations, and 2 × 50-m maximal sprints (Experimental), or no preloading session (Control). After a 2-h break, the players performed a set of six 30-m sprints and a Rugby-7s match. Recovery–stress state and salivary stress-marker levels were assessed before the preloading session (Pre), immediately after the preloading session (Post 1), before the testing session (Post 2), and after the testing session (Post 3). Results: Experimental–Control differences in performance across a repeated-sprint test consisting of six 30-m sprints were very likely trivial (+0.2, ±0.7%, 3/97/1%). During the match, the total distance covered and the frequency of decelerations were possibly lower (small) in Experimental compared with Control. Differences observed in the other parameters were unclear or possibly trivial. At Post 2, the perceived recovery–stress state was improved (small difference) in Experimental compared with Control. No difference in salivary cortisol response was observed, while the preconditioning session induced a higher stimulation of salivary testosterone and α-amylase. Conclusions: The players’ ability to repeat sprints and physical activity in match play did not improve, but their psychophysiological state was positively affected after the present preconditioning session.

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Lachlan J.G. Mitchell, Ben Rattray, Paul Wu, Philo U. Saunders and David B. Pyne

Purpose: Critical speed (CS) and supra-CS distance capacity (D′) are useful metrics for monitoring changes in swimmers’ physiological and performance capacities. However, the utility of these metrics across a season has not been systematically evaluated in high-level swimmers. Methods: A total of 27 swimmers (mean [SD]: 18 females, age = 19.1 [2.9] y, and 9 males, age = 19.5 [1.9] y) completed the 12 × 25-m swimming test multiple times (4 [3] tests/swimmer) across a 2-y period. Season-best times in all distances for the test stroke were sourced from publicly available databases. Swimmers’ distance speciality was determined as the event with the time closest to world record. Four metrics were calculated from the 12 × 25-m test: CS, D′, peak speed, and drop-off %. Results: Guyatt responsiveness index values were calculated to ascertain the practically relevant sensitivity of each 12 × 25-m metric: CS = 1.5, peak speed = 2.3, D′ = 2.1, and drop-off % = 2.6. These values are modified effect sizes; all are large effects. Bayesian mixed modeling showed substantial between-subjects differences between genders and strokes for each variable but minimal within-subject changes across the season. Drop-off % was lower in 200-m swimmers (14.0% [3.3%]) than in 100-m swimmers (18.1% [4.1%], P = .003, effect size = 1.10). Conclusions: The 12 × 25-m test is best suited to differentiating between swimmers of different strokes and events. Further development is needed to improve its utility in quantifying meaningful changes over a season for individual swimmers.

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Francesco Campa, Hannes Gatterer, Henry Lukaski and Stefania Toselli

Purpose: The exercise-induced increase in skin and body temperature, cutaneous blood flow, and electrolyte accumulation on the skin affects the validity of bioimpedance analysis to assess postexercise changes in hydration. This study aimed to assess the influence of a 10-min cold (22°C) shower on the time course of impedance measurements after controlled exercise. Methods: In total, 10 male athletes (age 26.2 [4.1] y and body mass index 23.9 [1.7] kg/m2) were tested on 2 different days. During both trials, athletes ran for 30 min on a treadmill in a room at 23°C. In a randomized crossover trial, the participants underwent a 10-min cold shower on the trial occasion and did not shower in the control trial. Bioimpedance analysis variables were measured before running (ie, baseline [T0]), immediately after exercising (T1), and 20 (T2), 40 (T3), and 60 min (T4) after the exercise. The shower was performed after T1 in the shower trial. Results: Body weight decreased similarly in both trials (−0.4% [0.1%], P < .001; −0.4% [0.1%], P < .001). Resistance and vector length returned to baseline at T2 in the shower trial, whereas baseline values were achieved at T3 in the control trial (P > .05). In the control trial, reactance remained at a lower level for the entire testing period (38.1 [6.9] vs 37.3 [6.7], P < .001). Forehead skin temperature returned to baseline values at T2 with shower, whereas it was still high at T4 without shower (P < .001). Conclusions: The present data show that a 10-min cold shower enables the stabilization of bioimpedance analysis measurements within 20 min after exercise, which might facilitate the assessment of hydration change after exercise.

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Brian Hanley, Trent Stellingwerff and Florentina J. Hettinga

Purpose: This was the first study to analyze high-resolution pacing data from multiple global championships, allowing for deeper and rigorous analysis of pacing and tactical profiles in elite-standard middle-distance racing. The aim of this study was to analyze successful and unsuccessful middle-distance pacing profiles and variability across qualifying rounds and finals. Methods: Finishing and 100-m-split speeds and season’s best times were collected for 265 men and 218 women competing in 800- and 1500-m races, with pace variability expressed using coefficient of variation. Results: In both events, successful athletes generally separated themselves from slower athletes in the final 200 m, not by speeding up but by avoiding slowing compared with competitors. This was despite different pacing profiles between events in the earlier part of the race preceding the end spurt. Approximately 10% of athletes ran season’s best times, showing a tactical approach to elite-standard middle-distance racing and possible fatigue across rounds. Men’s and women’s pacing profiles were remarkably similar within each event, but the previously undescribed seahorse-shaped profile in the 800-m (predominantly positive pacing) differed from the J-shaped negative pacing of the 1500-m. Pacing variability was high compared with world records, especially in the finals (coefficient of variation: 5.2–9.1%), showing that athletes need to be able to vary pace and cope with surges. Conclusions: The best athletes had the physiological capacity to vary pace and respond to surges through successive competition rounds. In competition-specific training, coaches should incorporate several sessions in which pace changes frequently and sometimes unexpectedly.

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Aitor Iturricastillo, Cristina Granados, Raúl Reina, José Manuel Sarabia, Ander Romarate and Javier Yanci

Purpose: To analyze the relationship between mean propulsive velocity (MPV) of the bar and relative load (percentage of the 1-repetition maximum [%1RM]) in the bench-press (BP) exercise and to determine the relationship of power variables (ie, mean concentric power [MP], mean propulsive power [MPP], and peak power [PP]) in change-of-direction ability, linear sprint, and repeated-sprint ability. Methods: A total of 9 Spanish First Division wheelchair basketball players participated in the study. All participants performed an isoinertial BP test in free execution mode, a 505 change-of-direction ability test, linear sprint test (20 m), and repeated-sprint ability test. Results: A nearly perfect and inverse relationship was observed for the BP exercise between the %1RM and MPV (r = −.97, R 2 = .945, P < .001). The maximum loads for MP, MPP, and PP were obtained between 48.1% and 59.4% of the 1RM. However, no significant correlations were observed between strength and wheelchair performance. Conclusions: Wheelchair basketball players with different functional impairments showed a nearly perfect and inverse relationship for the BP exercise between the %1RM and MPV; thus the MPV could be used to estimate the %1RM. This finding has important practical applications for velocity-based resistance training in that coaches would be able to prescribe and monitor training load. Conversely, the absence of association between BP performance and field tests might be due to other factors such as the wheelchair–user interface, trunk-muscle activity, or propulsion technique, apart from strength variables.

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Dustin J. Oranchuk, André R. Nelson, Adam G. Storey and John B. Cronin

Purpose: Regional muscle-architecture measures are reported widely; however, little is known about the variability of these measurements in the rectus femoris, vastus lateralis, and anterior and lateral vastus intermedius. The aim of this study was to quantify this variability. Methods: Regional muscle thickness, pennation angle (PA), and calculated and extended-field-of-view–derived fascicle length (FL) were quantified in 26 participants using ultrasonography across 51 limbs on 3 occasions. To quantify variability, the typical error of measurement (TEM) was multiplied by 2, and thresholds of 0.2–0.6 (small), 0.6–1.2 (moderate), 1.2–2.0 (large), 2.0–4.0 (very large), and >4.0 (extremely large) were applied. In addition, variability was deemed large when the intraclass correlation coefficient (ICC) was <.67 and coefficient of variation (CV) >10%, moderate when ICC > .67 or CV < 10% (but not both), and small when both ICC > .67 and CV < 10%. Results: Muscle thickness of all muscles and regions had low to moderate variability (ICC = .88–.98, CV = 2.4–9.3%, TEM = 0.15–0.47). PA of the proximal and distal vastus lateralis had low variability (ICC = .85–.96, CV = 3.8–8%) and moderate to large TEM (TEM = 0.42–0.83). PA of the rectus femoris was found to have moderate to very large variability (ICC = .38–.74, CV = 11.4–18.5%, TEM = 0.61–1.29) regardless of region. Extended-field-of-view–derived FL (ICC = .57–.94, CV = 4.1–11.5%, TEM = 0.26–0.88) was superior to calculated FL (ICC = .37–.84, CV = 7.4–17.9%, TEM = 0.44–1.33). Conclusions: Variability of muscle thickness was low in all quadriceps muscles and regions. Only rectus femoris PA and FL measurements were highly variable. The extended-field-of-view technique should be used to assess FL where possible. Inferences based on rectus femoris architecture should be interpreted with caution.

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Diogo V. Leal, Lee Taylor and John Hough

Purpose: Progressively overloading the body to improve physical performance may lead to detrimental states of overreaching/overtraining syndrome. Blunted cycling-induced cortisol and testosterone concentrations have been suggested to indicate overreaching after intensified training periods. However, a running-based protocol is yet to be developed or demonstrated as reproducible. This study developed two 30-min running protocols, (1) 50/70 (based on individualized physical capacity) and (2) RPETP (self-paced), and measured the reproducibility of plasma cortisol and testosterone responses. Methods: Thirteen recreationally active, healthy men completed each protocol (50/70 and RPETP) on 3 occasions. Venous blood was drawn preexercise, postexercise, and 30 min postexercise. Results: Cortisol was unaffected (both P > .05; 50/70, ηp2=.090; RPETP, ηp2=.252), while testosterone was elevated (both P < .05; 50/70, 35%, ηp2=.714; RPETP, 42%, ηp2=.892) with low intraindividual coefficients of variation (CVi) as mean (SD) (50/70, 7% [5%]; RPETP, 12% [9%]). Heart rate (50/70, effect size [ES] = 0.39; RPETP, ES = −0.03), speed (RPETP, ES = −0.09), and rating of perceived exertion (50/70 ES = −0.06) were unchanged across trials (all CVi < 5%, P < .05). RPETP showed greater physiological strain (P < .01). Conclusions: Both tests elicited reproducible physiological and testosterone responses, but RPETP induced greater testosterone changes (likely due to increased physiological strain) and could therefore be considered a more sensitive tool to potentially detect overtraining syndrome. Advantageously for the practitioner, RPETP does not require a priori exercise-intensity determination, unlike the 50/70, enhancing its integration into practice.