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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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Farzin Halabchi, Reza Mazaheri, Khashayar Sabeti, Masoud Yunesian, Zahra Alizadeh, Zahra Ahmadinejad, Seyed Mojtaba Aghili and Zahra Tavakol

Purpose: To compare the severity outcomes of COVID-19 disease between patients with and without regular sports participation. Methods: In a cross-sectional study, the authors investigated all patients who visited the emergency department of Imam Khomeini hospital with signs and symptoms of COVID-19 from February 20 to April 20, 2020. Then the authors assessed all patient outcomes (outpatient vs hospitalization or death). Finally, the authors compared the outcomes between athletes with regular sports participation and others, adjusting for confounding factors of age and sex. Results: Of all 4694 adult patients, 249 individuals (137 males and 112 females with mean [SD] age of 36.45 [9.77] y) had regular participation in different sport disciplines. Overall, 30 (12%) athletes were hospitalized or died (30 and 0, respectively) compared with 957 (21.5%) nonathletes (878 and 79, respectively). Athletes with regular sports participation were 1.49 times less likely to be hospitalized (P = .044). Conclusions: Regular sports participation may positively affect the clinical outcome, regardless of confounding factors of age and sex. The probability of hospitalization in athletes with regular sports participation was 33% lower than nonathletes. However, more longitudinal studies are needed to determine the causal effects.

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Vagner Deuel de Oliveira Tavares, Nicole Leite Galvão-Coelho, Joseph Firth, Simon Rosenbaum, Brendon Stubbs, Lee Smith, Davy Vancampfort and Felipe Barreto Schuch

Purpose: To examine the reliability and convergent validity of self-reported questionnaires (SRQs) to measure physical activity (PA). Methods: Systematic review with meta-analysis. The validity and reliability of SRQs to assess PA in people with mental disorders (January 20, 2020). Random-effects meta-analyses were performed pooling (1) test–retest correlations or (2) the convergent validity between the SRQs and objective measures (eg, accelerometry). Associations were provided in r values with the 95% confidence interval. Methodological quality was assessed. Results: A total of 9 unique studies (N = 1344; 40.5% females) were included. The authors found a moderate correlation test–retest reliability for PA SRQs in the assessment of vigorous PA (r = .69 [.38 to .85]; P = .001), moderate to vigorous PA (r = .63 [.25 to .84]; P = .003), moderate PA (r = .63 [.39 to .79]; P = .001), and good correlation total PA (r = .75 [.37 to .92]; P = .001). The SRQs have moderate correlations with objective measures for moderate to vigorous PA (r = .25 [.18 to .32]; P = .0001) and total PA (r = .47 [.28 to .62]; P = .005), a poor correlation for moderate PA (r = .18 [.03 to .36]; P = .047), and no correlation with vigorous PA (r = .06 [−.10 to .22]; P = .440). Conclusion: Current evidence indicates that SRQs are reliable over time to assess moderate, vigorous, and total PA levels and valid when assessing moderate PA.

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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.

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Christopher J. Stevens, Megan L.R. Ross and Roxanne M. Vogel

Menthol is effective at stimulating thermosensitive neurons that evoke pleasant cooling sensations. Internal application of menthol can be ergogenic for athletes, and hence, addition of menthol to sports nutrition products may be beneficial for athletes. The aim of this study was to develop a menthol energy gel for consumption during exercise and to determine acceptability and preferences for gels with different menthol concentrations. With a randomized, crossover, and double-blind placebo-controlled design, 40 endurance athletes (20 females) ingested an energy gel with a menthol additive at a high (0.5%; HIGH) or low concentration (0.1%; LOW), or a mint-flavored placebo (CON), on separate occasions during outdoor endurance training sessions. The athletes rated the gels for cooling sensation, mint flavor intensity, sweetness, and overall experience and provided feedback. Results are reported as median (interquartile range). Both menthol gels successfully delivered a cooling sensation, with a significantly greater response for HIGH (5.0 [4.0–5.0]) compared with LOW (3.5 [3.0–4.0]; p = .022) and CON (1.0 [1.0–2.0]; p < .0005), and LOW compared with CON (p < .0005). Ratings of mint flavor intensity followed the same trend as cooling sensation, while ratings of overall experience were significantly worse for HIGH (2.0 [1.0–3.0]) compared with LOW (4.0 [2.0–4.0]; p = .001) and CON (4.0 [3.0–4.0]; p < .0005). An energy gel with the addition of menthol at 0.1–0.5% provides a cooling sensation for athletes with a dose–response when ingested during exercise. The 0.1% concentration is recommended to maximize the overall experience of the gel.