Browse

You are looking at 1 - 10 of 5,166 items for :

  • Sport and Exercise Science/Kinesiology x
  • Physical Education and Coaching x
Clear All
Restricted access

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.

Open access

Shona L. Halson and David T. Martin

Restricted access

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.

Full access

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.

Restricted access

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.

Restricted access

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.

Restricted access

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.

Restricted access

Mariana B. Pinto, Patrícia M. Bock, Andressa S.O. Schein, Juliana Portes, Raíssa B. Monteiro, Beatriz D. Schaan and Beatriz D. Schaan

This study evaluated the effects of inspiratory muscle training (IMT) in glucose control and respiratory muscle function in patients with diabetes. It was a randomized clinical trial conducted at the Physiopathology Laboratory of the Hospital de Clínicas de Porto Alegre. Patients with Type 2 diabetes were randomly assigned to IMT or placebo-IMT (P-IMT), performed at 30% and 2% of maximal inspiratory pressure, respectively, every day for 12 weeks. The main outcome measures were HbA1c, glycemia, and respiratory muscle function. Thirty patients were included: 73.3% women, 59.6 ± 10.7 years old, HbA1c 8.7 ± 0.9% (71.6 ± 9.8 mmol/mol), and glycemia 181.8 ± 57.8 mg/dl (10.5 ± 3.2 mmol/L). At the end of the training, HbA1c was 8.2 ±0.3% (66.1 ± 3.3 mmol/mol) and 8.7 ± 0.3% (71.6 ± 3.3 mmol/mol) for the IMT and P-IMT groups, respectively (p = .8). Fasting glycemia decreased in both groups with no difference after training although it was lower in IMT at 8 weeks: 170.0 ± 11.4 mg/dl(9.4 ± 0.6 mmol/L) and 184.4 ± 15.0 mg/dl (10.2 ± 0.8 mmol/L) for IMT and P-IMT, respectively (p < .05). Respiratory endurance time improved in the IMT group (baseline = 325.9 ± 51.1 s and 305.0 ± 37.8 s; after 12 weeks = 441.1 ± 61.7 s and 250.7 ± 39.0 s for the IMT and P-IMT groups, respectively; p < .05). Considering that glucose control did not improve, IMT should not be used as an alternative to other types of exercise in diabetes. Higher exercise intensities or longer training periods might produce better results. The clinical trials identifier is NCT 03191435.