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Antonio Dello Iacono, Marco Beato and Israel Halperin

Purpose: To investigate whether providing athletes with a choice regarding the number of repetitions to complete in a potentiation protocol would enhance jumping performance compared with protocols in which the number of repetitions is predetermined. Methods: Fifteen male basketball players completed 4 testing sessions separated by 72 hours. In the first session, individual optimum power loads in the barbell jump squat were determined. In the following 3 sessions, the athletes completed 3 sets of 3 potentiation protocols using optimum power load jump squats in a partly randomized order: (1) The traditional condition included 6 repetitions per set, (2) the self-selected condition included a choice regarding the number of repetitions to complete per set, and (3) the imposed condition included the same number of repetitions per set as the self-selected condition, but the number was imposed on the athletes beforehand. The jumping performance was determined as jump squat test height and measured using a force platform before and 30 seconds, 4 minutes, and 8 minutes after completing the protocols. Results: The self-selected condition led to superior jumping performance compared with the 2 other conditions across all post measures (P < .05; range: 0.3–1.3 cm). Compared with the traditional condition, the imposed condition led to superior jumping performance across all post measures (range: 0.2–0.45 cm), although not statistically significant at post 4 minutes and post 8 minutes. Conclusions: Choice provision concerning how many repetitions to complete in a potentiation protocol is a useful performance-enhancing strategy. Improved potentiation–fatigue ratio and motivational factors are sought to explain these effects.

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Lisa Steidl-Müller, Carolin Hildebrandt, Christoph Ebenbichler, Roland Luchner, Carson Patterson, Erich Müller, Christoph Gonaus and Christian Raschner

Purpose: The aim of this study was to evaluate whether anthropometric and fitness characteristics have changed between former and current elite male and female Austrian young ski racers (U11–U15). Methods: A battery of anthropometric, general, and skiing-specific fitness tests was conducted annually. In total, 1517 participants (846 males, 671 females) who were tested in 2005–2009 (“former athletes” n = 805) and 2015–2019 (“current athletes” n = 712) were included. Independent t tests and Cohen d were calculated to compare the two 5-y periods, separated by sex and age group. The level of significance was set at P < .05. Results: No significant change in anthropometric characteristics was found over the decade. Current young ski racers performed significantly better in the maximal core flexion strength test in all age categories (ES = 0.88–1.50; P < .02). Core extension strength values were higher in current male U12 and female U12 and U13 athletes (ES = 0.54–0.71; P < .01) and better postural stability values in the lateral direction were found in the age categories U12 and U14 (ES = 0.36–0.68; P < .05), as well as in the forward/backward direction in the age categories U12–U14 (ES = 0.38–1.12; P < .03). Lower-leg extension strength values were apparent in the current U13–U15 age categories (ES = 0.36–1.03; P ≤ .001) and lower drop-jump reactive strength indices in the U13–U15 male athletes (ES = 0.49–0.80; P < .01). Conclusions: Current and former young ski racers differ significantly in some fitness parameters, which might lead to the assumption that some aspects (such as core strength) have gained more focus in athletic training during the last years compared with 15 y ago.

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Shona L. Halson and David T. Martin

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Celina H. Shirazipour and Amy E. Latimer-Cheung

A gap in knowledge exists regarding how to maintain physical activity (PA) for individuals with acquired disabilities following initial introductory experiences. The current study aimed to contribute to filling this gap by exploring the PA pathways of military veterans with a physical disability, particularly those who maintain long-term PA, from impairment to the present. Veterans with a physical disability (N = 18) participated in interviews exploring their PA history and experiences. A reflexive thematic analysis was conducted to generate common pathways in PA participation, as well as to examine which elements of participation supported PA maintenance. Three long-term pathways were identified—two parasport pathways and one recreational PA pathway. Four elements of participation (i.e., mastery, challenge, belongingness, meaning) supported to maintain PA at key junctures. This knowledge provides further understanding of how to promote long-term PA for individuals with acquired disabilities and can support advancements in theory, as well as program development.

Open access

Neil D. Clarke and Darren L. Richardson

There is growing evidence that caffeine and coffee ingestion prior to exercise provide similar ergogenic benefits. However, there has been a long-standing paradigm that habitual caffeine intake may influence the ergogenicity of caffeine supplementation. The aim of the present study was to investigate the effect of habitual caffeine intake on 5-km cycling time-trial performance following the ingestion of caffeinated coffee. Following institutional ethical approval, in a double-blind, randomized, crossover, placebo-controlled design, 46 recreationally active participants (27 men and 19 women) completed a 5-km cycling time trial on a cycle ergometer 60 m in following the ingestion of 0.09 g/kg coffee providing 3 mg/kg of caffeine, or a placebo. Habitual caffeine consumption was assessed using a caffeine consumption questionnaire with low habitual caffeine consumption defined as <3 and ≥6 mg · kg−1 · day−1 defined as high. An analysis of covariance using habitual caffeine intake as a covariant was performed to establish if habitual caffeine consumption had an impact on the ergogenic effect of coffee ingestion. Sixteen participants were classified as high-caffeine users and 30 as low. Ingesting caffeinated coffee improved 5-km cycling time-trial performance by 8 ± 12 s; 95% confidence interval (CI) [5, 13]; p < .001; d = 0.30, with low, 9±14 s; 95% CI [3, 14]; p = .002; d = 0.18, and high, 8 ± 10 s; 95% CI [−1, 17]; p = .008; d = 0.06, users improving by a similar magnitude, 95% CI [−12, 12]; p = .946; d = 0.08. In conclusion, habitual caffeine consumption did not affect the ergogenicity of coffee ingestion prior to a 5-km cycling time trial.

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George P. Robinson, Sophie C. Killer, Zdravko Stoyanov, Harri Stephens, Luke Read, Lewis J. James and Stephen J. Bailey

This study investigated whether supplementation with nitrate-rich beetroot juice (BR) can improve high-intensity intermittent running performance in trained males in normoxia and different doses of normobaric hypoxia. Eight endurance-trained males (V˙O2peak, 62 ± 6 ml·kg−1·min−1) completed repeated 90 s intervals at 110% of peak treadmill velocity, from an initial step incremental test, interspersed by 60 s of passive recovery until exhaustion (T lim). Participants completed the first three experimental trials during days 3, 5, and 7 of BR or nitrate-depleted beetroot juice (PLA) supplementation and completed the remaining experimental visits on the alternative supplement following at least 7 days of washout. The fraction of inspired oxygen during visits 1–3 was either 0.209, 0.182, or 0.157, equivalent to an altitude of 0, 1,200, and 2,400 m, respectively, and this order was replicated on visits 4–6. Arterial oxygen saturation declined dose dependently as fraction of inspired oxygen was lowered (p < .05). Plasma nitrite concentration was higher pre- and postexercise after BR compared with PLA supplementation (p < .05). There was no difference in Tlim between PLA and BR at 0 m (445 [324, 508] and 410 [368, 548] s); 1,200 m (341 [270, 390] and 332 [314, 356] s); or 2,400 m (233 [177, 373] and 251 [221, 323] s) (median and [interquartile range]; p > .05). The findings from this study suggest that short-term BR supplementation does not improve high-intensity intermittent running performance in endurance-trained males in normoxia or at doses of normobaric hypoxia that correspond to altitudes at which athletes typically train while on altitude training camps.

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Ali Daraei, Sajad Ahmadizad, Hiwa Rahmani, Anthony C. Hackney, Kelly E. Johnson, Ismail Laher, Ayoub Saeidi and Hassane Zouhal

The effects of acute consumption of L-Arginine (L-Arg) in healthy young individuals are not clearly defined, and no studies on the effects of L-Arg in individuals with abnormal body mass index undertaking strenuous exercise exist. Thus, we examined whether supplementation with L-Arg diminishes cardiopulmonary exercise testing responses, such as ventilation (VE), VE/VCO2, oxygen uptake (VO2), and heart rate, in response to an acute session of high-intensity interval exercise (HIIE) in overweight men. A double-blind, randomized crossover design was used to study 30 overweight men (age, 26.5 ± 2.2 years; body weight, 88.2 ± 5.3 kilogram; body mass index, 28.0 ± 1.4 kg/m2). Participants first completed a ramped-treadmill exercise protocol to determine VO2max velocity (vVO2max), after which they participated in two sessions of HIIE. Participants were randomly assigned to receive either 6 g of L-Arg or placebo supplements. The HIIE treadmill running protocol consisted of 12 trials, including exercise at 100% of vVO2max for 1 min interspersed with recovery intervals of 40% of vVO2max for 2 min. Measurements of VO2 (ml·kg−1·min−1), VE (L/min), heart rate (beat per min), and VE/VCO2 were obtained. Supplementation with L-Arg significantly decreased all cardiorespiratory responses during HIIE (placebo+HIIE vs. L-Arg+HIIE for each measurement: VE [80.9 ± 4.3 L/min vs. 74.6 ± 3.5 L/min, p < .05, ES = 1.61], VE/VCO2 [26.4 ± 1.3 vs. 24.4 ± 1.0, p < .05, ES = 1.8], VO2 [26.4 ± 0.8 ml·kg−1·min−1 vs. 24.4 ± 0.9 ml·kg−1·min−1, p < .05, ES = 2.2], and heart rate [159.7 ± 6.3 beats/min vs. 155.0 ± 3.7 beats/min, p < .05, d = 0.89]). The authors conclude consuming L-Arg before HIIE can alleviate the excessive physiological strain resulting from HIIE and help to increase exercise tolerance in participants with a higher body mass index who may need to exercise on a regular basis for extended periods to improve their health.

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Naroa Etxebarria, Brad Clark, Megan L. Ross, Timothy Hui, Roland Goecke, Ben Rattray and Louise M. Burke

The ingestion of quinine, a bitter tastant, improves short-term (30 s) cycling performance, but it is unclear whether this effect can be integrated into the last effort of a longer race. The purpose of this study was to determine whether midtrial quinine ingestion improves 3,000-m cycling time-trial (TT) performance. Following three familiarization TTs, 12 well-trained male cyclists (mean ± SD: mass = 76.6 ± 9.2 kg, maximal aerobic power = 390 ± 50 W, maximal oxygen uptake = 4.7 ± 0.6 L/min) performed four experimental 3,000-m TTs on consecutive days. This double-blind, crossover design study had four randomized and counterbalanced conditions: (a) Quinine 1 (25-ml solution, 2 mM of quinine); (b) Quinine 2, replicate of Quinine 1; (c) a 25-ml sweet-tasting no-carbohydrate solution (Placebo); and (d) 25 ml of water (Control) consumed at the 1,850-m point of the TT. The participants completed a series of perceptual scales at the start and completion of all TTs, and the power output was monitored continuously throughout all trials. The power output for the last 1,000 m for all four conditions was similar: mean ± SD: Quinine 1 = 360 ± 63 W, Quinine 2 = 367 ± 63 W, Placebo = 364 ± 64 W, and Control = 367 ± 58 W. There were also no differences in the 3,000-m TT power output between conditions. The small perceptual differences between trials at specific 150-m splits were not explained by quinine intake. Ingesting 2 mM of quinine during the last stage of a 3,000-m TT did not improve cycling performance.

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Jihyeon Lee and Laura Azzarito

Recent reports have indicated that recent immigrant minority girls are the least physically active in the United States and are often categorized as “bodies-at-risk” for obesity and other health issues. This dominant “at-risk” discourse presents a negative image of recent immigrant minority girls and positions them as “others.” This participatory visual study thus explored how the recent immigrant minority girls co-constructed and shared their (dis)engagement in physical culture on a popular social media platform: Instagram. Results demonstrated that the use of Instagram served two interrelated functions: (a) a constructive pedagogical space in which the participants examined, learned, and expressed their knowledge related to physical activity and health and (b) an empowering tool to create “Thirdspace” in which the participants’ visual texts opened up the space of inclusion and fluidity. Despite potential risks, it was suggested that the use of Instagram was beneficial for conducting research with, for, and about marginalized youth.