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Sophia Nimphius and Matthew J. Jordan

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Steve H. Faulkner and Philippa Jobling

Purpose: Cycling time trials (TTs) are characterized by riders’ adopting aerodynamic positions to lessen the impact of aerodynamic drag on velocity. The optimal performance requirements for TTs likely exist on a continuum of rider aerodynamics versus physiological optimization, yet there is little empirical evidence to inform riders and coaches. The aim of the present study was to investigate the relationship between aerodynamic optimization, energy expenditure, heat production, and performance. Methods: Eleven trained cyclists completed 5 submaximal exercise tests followed by a TT. Trials were completed at hip angles of 12° (more horizontal), 16°, 20°, 24° (more vertical), and their self-selected control position. Results: The largest decrease in power output at anaerobic threshold compared with control occurred at 12° (−16 [20] W, P = .03; effect size [ES] = 0.8). There was a linear relationship between upper-body position and heat production (R 2 = .414, P = .04) but no change in mean body temperature, suggesting that, as upper-body position and hip angle increase, convective and evaporative cooling also rise. The highest aerodynamic–physiological economy occurred at 12° (384 [53] W·C d A −1·L−1·min−1, ES = 0.4), and the lowest occurred at 24° (338 [28] W·C d A −1·L−1·min−1, ES = 0.7), versus control (367 [41] W·C d A −1·L−1·min−1). Conclusion: These data suggest that the physiological cost of reducing hip angle is outweighed by the aerodynamic benefit and that riders should favor aerodynamic optimization for shorter TT events. The impact on thermoregulation and performance in the field requires further investigation.

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Derrick D. Brown, Jurjen Bosga and Ruud G.J. Meulenbroek

This study investigated effects of mirror and metronome use on spontaneous upper body movements by 10 preprofessional dancers in a motor task in which maximally diverse upper body movement patterns were targeted. Hand and trunk accelerations were digitally recorded utilizing accelerometers and analyzed using polar frequency distributions of the realized acceleration directions and sample entropy of the acceleration time. Acceleration directions were more variably used by the arms than by the torso, particularly so when participants monitored their performance via a mirror. Metronome use hardly affected the predictability of the acceleration time series. The findings underscore the intrinsic limitations that people experience when being asked to move randomly and reveal moderate effects of visual and acoustic constraints on doing so in dance.

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Naoya Takei, Katsuyuki Kakinoki, Olivier Girard and Hideo Hatta

Background: Training in hypoxia versus normoxia often induces larger physiological adaptations, while this does not always translate into additional performance benefits. A possible explanation is a reduced oxygen flux, negatively affecting training intensity and/or volume (decreasing training stimulus). Repeated Wingates (RW) in normoxia is an efficient training strategy for improving both physiological parameters and exercise capacity. However, it remains unclear whether the addition of hypoxia has a detrimental effect on RW performance. Purpose: To test the hypothesis that acute moderate hypoxia exposure has no detrimental effect on RW, while both metabolic and perceptual responses would be slightly higher. Methods: On separate days, 7 male university sprinters performed 3 × 30-s Wingate efforts with 4.5-min passive recovery in either hypoxia (FiO2: 0.145) or normoxia (FiO2: 0.209). Arterial oxygen saturation was assessed before the first Wingate effort, while blood lactate concentration and ratings of perceived exertion were measured after each bout. Results: Mean (P = .92) and peak (P = .63) power outputs, total work (P = .98), and the percentage decrement score (P = .25) were similar between conditions. Arterial oxygen saturation was significantly lower in hypoxia versus normoxia (92.0% [2.8%] vs 98.1% [0.4%], P < .01), whereas blood lactate concentration (P = .78) and ratings of perceived exertion (P = .51) did not differ between conditions. Conclusion: In sprinters, acute exposure to moderate hypoxia had no detrimental effect on RW performance and associated metabolic and perceptual responses.

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Carena Winters

Evidence supporting exercise as a medicine in the prevention and management of chronic disease is indisputable. Created in 2007, Exercise is Medicine® (EIM) aims to make physical activity assessment and promotion a standard in clinical care, connecting health care professionals with qualified exercise professionals to provide evidence-based physical activity resources and programs to everyone of all abilities. Opportunities exist for exercise professionals in several areas within EIM, including exercise referral and prescription, EIM on Campus, and physical activity and EIM education. Connections between EIM and kinesiology and the need for exercise professionals to contribute to the EIM evidence are discussed.

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Michelle Hamilton, Karen Meaney and Melissa Martinez

Promoting the success of all students is one of four institutional goals at Texas State University. Retention and graduation rates provide information regarding the academic progress and success of specific student cohorts. To gain a deeper insight into student success within the undergraduate kinesiology/exercise and sports science program at Texas State University, an equity audit was conducted during the fall 2019 academic semester. An equity audit provides a lens to critically examine institutional data to identify inequities in academic programs and student achievement based on specific variables, such as gender, age, race, and socioeconomic status. This article provides a model for conducting an equity audit in kinesiology/exercise and sports science programs, reports the findings, and highlights strategic actions implemented to combat inequities in student success.

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Helene Pedersen, Atle Hole Saeterbakken, Markus Vagle, Marius Steiro Fimland and Vidar Andersen

Purpose: The Nordic hamstring exercise (NHE) has been shown to considerably reduce hamstring injuries among soccer players. However, as the load in the NHE is the person’s own bodyweight, it is a very heavy exercise and difficult to individualize. The flywheel inertial leg curl (FLC) could be an alternative since the eccentric overload is based on the amount of work produced in the concentric movement. Therefore, the primary aim of this study was to compare the activation in the hamstrings at long muscle lengths in the NHE and the FLC in amateur soccer players. Methods: Fifteen male amateur soccer players performed 5 repetitions in each exercise in a randomized and counterbalanced order. The concentric and eccentric movements were divided into lower and upper phases. Surface EMG was measured distally, proximally, and in the middle, at both muscles. Results: In the lower phase in the eccentric movement, there were no significant differences between the 2 exercises (P = .101–.826). In the lower concentric movement, the FLC led to higher activation in all parts of both the biceps femoris (31%–52%, P < .001) and the semitendinosus (20%–35%, P = .001–.023). Conclusion: Both exercises activated the hamstrings similarly at long muscle lengths during eccentric contractions (Nordic hamstring, nonsignificantly higher). However, when performing concentric contractions, the FLC induced higher activations. Therefore, the FLC could be a useful alternative to the NHE and particularly suitable for weaker athletes before progressing to NHE.

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Jinhui Li, Chen Li, Bing Xun Chia, Xinran Chen, Tan Phat Pham and Yin-Leng Theng

This study examined how different types of social interaction and competitive information in exergaming affect older adults’ motivation and attitude toward playing exergames. A 2 (time: pre- vs. posttest) × 3 (social interaction: play alone vs. play with peer vs. play with youth) × 2 (competition: competition informed vs. noncompetition informed) mixed experiment was conducted with 319 Singaporean older adults over 6 weeks through a three-way analysis of variance. Social interaction was found to significantly affect the changes of extrinsic motivation over time, while competitive information affected intrinsic motivation significantly. The results showed significant three-way interaction effects between time, social interaction, and competitive information on older adults’ extrinsic and intrinsic motivations. The changes of attitude over time were not affected by either social interaction or competitive information. The findings contribute to aging research and advance the knowledge of potential factors that promote the effective implementation of exergames for community older adults.

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Svend Erik Mathiassen

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Filippo Dolci, Andrew E. Kilding, Tania Spiteri, Paola Chivers, Ben Piggott, Andrew Maiorana and Nicolas H. Hart

Purpose: To evaluate the reliability of new change-of-direction-economy tests (assessing energetic efficiency when performing continuous shuttle runs) compared with common running-economy tests in soccer players Methods: Sixteen subelite, male soccer players were recruited to perform a testing battery involving running economy (RE), 10-m shuttle-running economy (SRE10), and 20-m shuttle-running economy (SRE20) at 8.4 km·h−1 mean speed on 2 different days within 48 hours. SRE10 and SRE20 consisted of continuous shuttle runs interspersed with 180° directional changes. During the RE, SRE20, and SRE10 tests, respiratory exchange ratio and oxygen uptake were collected and used to calculate the movement-economy values over any running condition as oxygen cost and energetic cost. The secondary variables (carbon dioxide production, heart rate, minute ventilation, and blood lactate) were also monitored during all tests. Results: Depending on expression (oxygen cost or energetic cost), reliability was established for RE (CV: 5.5%–5.8%; ICC = .77–.88), SRE10 (CV: 3.5%–3.8%; ICC = .78–.96), and SRE20 (CV: 3.5%–3.8%; ICC = .66–.94). All secondary physiological variables reported good reliability (CV < 10%), except for blood lactate (CV < 35.8). The RE, SRE10, and SRE20 tests show good reliability in soccer players, whereas blood lactate has the highest variability among physiological variables during the economy tests. Conclusion: The assessment of change-of-direction economy through performing 20- and 10-m shuttle runs is reliable and can be applied to evaluate soccer players’ energetic movement efficiency under more soccer-specific running conditions.