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João Paulo Limongi França Guilherme, Ekaterina A. Semenova, Hirofumi Zempo, Gabriel L. Martins, Antonio H. Lancha Junior, Eri Miyamoto-Mikami, Hiroshi Kumagai, Takuro Tobina, Keisuke Shiose, Ryo Kakigi, Takamasa Tsuzuki, Noriko Ichinoseki-Sekine, Hiroyuki Kobayashi, Hisashi Naito, Oleg V. Borisov, Elena S. Kostryukova, Nikolay A. Kulemin, Andrey K. Larin, Edward V. Generozov, Noriyuki Fuku and Ildus I. Ahmetov

Purpose: To replicate previous genome-wide association study identified sprint-related polymorphisms in 3 different cohorts of top-level sprinters and to further validate the obtained results in functional studies. Methods: A total of 240 Japanese, 290 Russians, and 593 Brazilians were evaluated in a case-control approach. Of these, 267 were top-level sprint/power athletes. In addition, the relationship between selected polymorphisms and muscle fiber composition was evaluated in 203 Japanese and 287 Finnish individuals. Results: The G allele of the rs3213537 polymorphism was overrepresented in Japanese (odds ratio [OR]: 2.07, P = .024) and Russian (OR: 1.93, P = .027) sprinters compared with endurance athletes and was associated with an increased proportion of fast-twitch muscle fibers in Japanese (P = .02) and Finnish (P = .041) individuals. A meta-analysis of the data from 4 athlete cohorts confirmed that the presence of the G/G genotype rather than the G/A+A/A genotypes increased the OR of being a sprinter compared with controls (OR: 1.49, P = .01), endurance athletes (OR: 1.79, P = .001), or controls + endurance athletes (OR: 1.58, P = .002). Furthermore, male sprinters with the G/G genotype were found to have significantly faster personal times in the 100-m dash than those with G/A+A/A genotypes (10.50 [0.26] vs 10.76 [0.31], P = .014). Conclusion: The rs3213537 polymorphism found in the CPNE5 gene was identified as a highly replicable variant associated with sprinting ability and the increased proportion of fast-twitch muscle fibers, in which the homozygous genotype for the major allele (ie, the G/G genotype) is preferable for performance.

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Antonis Kesisoglou, Andrea Nicolò and Louis Passfield

Purpose: To examine the effect of cycling exercise intensity and duration on subsequent performance and to compare the resulting acute performance decrement (APD) with total work done (TWD) and corresponding training-load (TL) metrics. Methods: A total of 14 male cyclists performed a 5-minute time trial (TT) as a baseline and after 4 initial exercise bouts of varying exercise intensity and duration. The initial exercise bouts were performed in a random order and consisted of a 5- and a 20-minute TT and a 20- and a 40-minute submaximal ride. The resulting APD was calculated as the percentage change in 5-minute TT from baseline, and this was compared with the TWD and TL metrics for the corresponding initial exercise bout. Results: Average power output was different for each of the 4 initial exercise bouts (ηp2=.971; P < .001), and all bouts resulted in an APD. But APD was only different when comparing maximal with submaximal bouts (ηp2=.862; P < .001). The APD contradicted TWD and TL metrics and was not different when comparing 5- and 20-minute maximal TTs or the 20- and 40-minute submaximal bouts. In contrast, TL metrics were different for all training sessions (ηp2=.970; P < .001). Conclusion: An APD is found after initial exercise bouts consisting of 5- and 20-minute TTs and after 20- and 40-minute of submaximal exercise that is not consistent with the corresponding values for TWD or TL. This discrepancy highlights important shortcomings when using TWD and TL to compare exercise bouts of different intensity and duration.

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Jon L. Weller

In Alberta, Canada during the 1960s and early 1970s the popularity of recreational paddling expanded considerably. The reasons for this were varied, including wider demographic and economic shifts that produced a population that was both able, with time and the means, and eager to engage in these activities. But at the same time there was a notable change in the material reality of the sport brought on by the development of new construction techniques and materials. The goal of this article is to investigate the changing nature of recreational paddling in the 1960s and 70s with a focus on the influence that changing materials and construction methods had on these processes. Developed for other commercial purposes, fiberglass provided paddlers in Alberta with a means of constructing more robust canoes cheaply, quickly, and with a great deal of customization. To facilitate this construction, paddlers came together to share knowledge, materials, designs, and labor. In turn, these boatbuilding workshops became the nucleus of a budding and ultimately vibrant paddling community in the province. Moreover, the increased durability and design adaptability allowed paddlers to push the limits of the sport and successively redesign and further specialize the boats allowing for even greater skill development.

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Jim Watkins

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Matthew Hodler and Callie Batts Maddox

Miami University has used Native American imagery to promote itself since its founding. In 1929, Miami teams began using the racist term Redsk*ns. In 1996–1997, they changed the name to RedHawks. Despite the strengthening relationship between the university and the tribe, the racist mascot imagery remained visible in the university community. In 2017–2018, the university returned to Native American imagery by unveiling a new “Heritage Logo” to represent a commitment to restoring the Myaamia language and culture. In this paper, the authors used tribal critical race theory to analyze how the Heritage Logo represents a point of interest convergence, where symbols of the tribe signal acceptance and recognition of the Myaamia people, while institutional racism and the possessive investment of whiteness are left ignored and unaddressed.

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Matthew Lamont

Existing conceptualizations of active sport tourism lack an empirical foundation in explaining the processes of embodiment through which active sport tourists engage with destination space. Adopting an autophenomenographic perspective, this paper explores embodiment in the context of a cycling tourism experience encompassing six iconic mountain passes within the French Alps synonymous with the Tour de France. Qualitative data draw attention to kinaesthetic and visceral sensations arising through multisensory feedback, along with affective responses produced as the body traverses venerated sport landscapes. This research highlights mind–body processes that shape mobile, active sport tourism experiences and provides an empirical and conceptual foundation to inform future studies of embodiment in active sport tourism.

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Taylor K. Dinyer, Pasquale J. Succi, M. Travis Byrd, Caleb C. Voskuil, Evangeline P. Soucie and Haley C. Bergstrom

This study determined the load- and limb-dependent neuromuscular responses to fatiguing, bilateral, leg extension exercise performed at a moderate (50% one-repetition maximum [1RM]) and high load (80% 1RM). Twelve subjects completed 1RM testing for the bilateral leg extension, followed by repetitions to failure at 50% and 80% 1RM, on separate days. During all visits, the electromyographic (EMG) and mechanomyographic (MMG), amplitude (AMP) and mean power frequency (MPF) signals were recorded from the vastus lateralis of both limbs. There were no limb-dependent responses for any of the neuromuscular signals and no load-dependent responses for EMG AMP, MMG AMP, or MMG MPF (p = .301–.757), but there were main effects for time that indicated increases in EMG and MMG AMP and decreases in MMG MPF. There was a load-dependent decrease in EMG MPF over time (p = .032) that suggested variability in the mechanism responsible for metabolite accumulation at moderate versus high loads. These findings suggested that common drive from the central nervous system was used to modulate force during bilateral leg extension performed at moderate and high loads.

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Nathalie Berninger, Gregory Knell, Kelley Pettee Gabriel, Guy Plasqui, Rik Crutzen and Gill Ten Hoor

Objectives: To examine the bidirectional association of sleep duration with proportions of time spent in physical behaviors among Dutch adolescents. Methods: Adolescents (n = 294, 11–15 years) completed sleep diaries and wore an accelerometer (ActiGraph) over 1 week. With linear mixed-effects models, the authors estimated the association of sleep categories (short, optimal, and long) with the following day’s proportion in physical behaviors. With generalized linear mixed models with binomial distribution, the authors estimated the association of physical behavior proportions on sleep categories. Physical behavior proportions were operationalized using percentages of wearing time and by applying a compositional approach. All analyses were stratified by gender accounting for differing developmental stages. Results: For males (number of observed days: 345, n = 83), short as compared with optimal sleep was associated with the following day’s proportion spent in sedentary (−2.57%, p = .03, 95% confidence interval [CI] [−4.95, −0.19]) and light-intensity activities (1.96%, p = .02, 95% CI [0.27, 3.65]), which was not significant in the compositional approach models. Among females (number of observed days: 427, n = 104), long sleep was associated with the proportions spent in moderate- to vigorous-intensity physical activity (1.69%, p < .001, 95% CI [0.75, 2.64]) and in sedentary behavior (−3.02%, p < .01, 95% CI [−5.09, −0.96]), which was replicated by the compositional approach models. None of the associations between daytime activity and sleep were significant (number of obs.: 844, n = 204). Conclusions: Results indicate partial associations between sleep and the following day’s physical behaviors, and no associations between physical behaviors and the following night’s sleep.

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Stephanie L. Silveira, Jessica F. Baird and Robert W. Motl

Three hundred and sixty-three older adults with multiple sclerosis completed a cross-sectional study examining hierarchical correlates of physical activity using a social cognitive theory perspective within a social ecological model (i.e., built environment, social environment, and individual social cognitive theory variables). Hierarchical linear regression analyses were conducted, wherein significant associations were noted for built environment (i.e., land-use mix diversity and aesthetics) and physical activity in Step 1 (R 2 = .09). Social and built environment were significant correlates in Step 2 (R 2 = .15). Finally in Step 3, individual social cognitive theory variables (i.e., self-efficacy and outcome expectations) were the only significant correlates of total physical activity (R 2 = .38). Results were comparable for health-promoting physical activity; however, self-efficacy was the only significant correlate in Step 3 (R 2 = .36). This study provides guidance for researchers and practitioners on relevant targets for tailoring interventions for older adults with multiple sclerosis and supports an emphasis on self-efficacy as a primary predictor of health behavior change.