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Kimberly Bigelow and Michael L. Madigan

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Stuart A. McErlain-Naylor

The aim of this study was to investigate student experiences of publishing undergraduate research in biomechanics. A total of 29 former students with experience of publishing peer-reviewed undergraduate biomechanics research completed an online survey regarding their perceived benefits, level of involvement, and experiences in aspects of the research process. On average, students perceived their experiences to be “largely helpful” or greater in all aspects. Areas were identified corresponding to: the greatest perceived benefits (eg, understanding of the research process); the least perceived benefits (eg, statistical analysis skills); the greatest student involvement (eg, reading relevant literature); and the least student involvement (eg, developing hypotheses and/or methods). A thematic analysis of open question responses identified themes relating to: future career, skills, scientific process, intra- and interpersonal factors, and pedagogy. Common intended learning outcomes may be achieved through involvement in the research process independently of the level of staff involvement. Staff should be encouraged to involve students in publishable biomechanics research projects where this is possible without compromising research standards and should explore ways of recreating the publishing process internally for all students.

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Nicole K. Nathan, Rachel L. Sutherland, Kirsty Hope, Nicole J. McCarthy, Matthew Pettett, Ben Elton, Rebecca Jackson, Stewart G. Trost, Christophe Lecathelinais, Kathryn Reilly, John H. Wiggers, Alix Hall, Karen Gillham, Vanessa Herrmann and Luke Wolfenden

Aim: To assess the impact of a multistrategy intervention designed to improve teachers’ implementation of a school physical activity (PA) policy on student PA levels. Methods: A cluster-randomized controlled trial was conducted in 12 elementary schools. Policy implementation required schools to deliver 150 minutes of organized PA for students each week via physical education, sport, or class-based activities such as energizers. Schools received implementation support designed using the theoretical domains framework to help them implement the current policy. Results: A total of 1,502 children in kindergarten to grade 6 participated. At follow-up compared with control, students attending intervention schools had, measured via accelerometer, significantly greater increases in school day counts per minute (97.5; 95% confidence interval [CI], 64.5 to 130.4; P < .001) and moderate to vigorous physical activity (MVPA) (3.0; 95% CI, 2.2–3.8, P < .001) and a greater decrease in sedentary time (−2.1; 95% CI, −3.9 to −0.4, P = .02) per school day. Teachers in intervention schools delivered significantly more minutes (36.6 min) of PA to their students at follow-up (95% CI, 2.7–70.5, P = .04). Conclusions: Supporting teachers to implement a PA policy improves student PA. Additional strategies may be needed to support teachers to implement activities that result in larger gains in student MVPA.

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John Stoszkowski, Áine MacNamara, Dave Collins and Aran Hodgkinson

Recent developments have seen a growth in coaching, with an associated boom in interest on how it may be optimised. Clearly, the authors applaud this evolution. This growth has been parallelled by an explosion in the availability of information, driven through Internet access and the phenomenon of social media. Unfortunately, however, this juxtaposition of interest and availability has not been matched by the application or exercise of effective quality control. While much of what is available is well intentioned, a tendency for poor quality and possibly less positively targeted “bullshit” has also arisen. In this insights paper, the authors have considered some of the reasons why and argued that an emphasis on the development of critical and analytical thinking, as well as a scepticism towards the sources of information, would be a positive step against coach susceptibility to bullshit. In doing so, and to encourage more critical consumption of the “knowledge” available, the authors presented a checklist to help coaches assess the veracity of claims and sift through the noise of the coaching landscape.

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Tomas Vetrovsky, Dan Omcirk, Jan Malecek, Petr Stastny, Michal Steffl and James J. Tufano

Following a 4-week control period, 24 older men and women (55–91 years) attended a 4-week progressive jumping program to determine whether assisted jumping could be safely and effectively implemented as a novel stimulus in healthy older adults. Bodyweight countermovement jump performance, isometric and isokinetic strength, postural stability, and exercise enjoyment were assessed before the control period, before the training intervention, and after the training intervention. Following the 4-week intervention, eccentric quadriceps strength increased by 19 N·m (95% confidence interval [2, 36], p = .013), bodyweight countermovement jump height increased by 1.7 cm (95% CI [0.5, 2.9], p < .001), postural sway improved by 2.1 mm/s (95% CI [0.3, 4.0], p = .026), and the participants’ perceived exercise enjoyment improved (p = .026). Therefore, using assisted jumping to induce an overspeed training stimulus in a jump training program resulted in similar performance improvements as in previous studies in older populations but with less training volume and a shorter training duration.

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Danny Lum and Abdul Rashid Aziz

Force–time characteristics obtained during isometric strength tests are significantly correlated to various sporting movements. However, data on the relationship between isometric force–time characteristics and sprint kayaking performance are lacking in the literature. Purpose: The purpose of the study was, therefore, to investigate the relationship between sprint kayaking performance with ergometer performance and measures from 3 isometric strength tests: isometric squat, isometric bench press, and isometric prone bench pull. Methods: A total of 23 sprint kayaking athletes performed all 3 tests, at 90° and 120° knee angles for isometric squat and at elbow angles for isometric bench press and isometric prone bench pull, and a 200-m sprint on-water to attain the fastest time-to-completion (OWTT) possible and on a kayak ergometer to attain the highest mean power (LABTT) possible. Results: There was a significant inverse correlation between OWTT and LABTT (r = −.90, P < .001). The peak forces achieved from all isometric strength tests were significantly correlated with time-to-completion for OWTT and mean power for LABTT (r = −.44 to −.88, P < .05 and .47 to .80, P < .05, respectively). OWTT was significantly correlated with the peak rate of force development during all isometric tests except for the isometric squat at a 120° knee angle (r = −.47 to −.62, P < .05). LABTT was significantly correlated with peak rate of force development from the isometric bench press and isometric prone bench pull (r = .64–.86, P < .01). Conclusion: Based on the observed strong correlations, the mean power attained during LABTT is a good predictor of OWTT time-to-completion. Furthermore, upper- and lower-body maximum strength and peak rate of force development are equally important for on-water and ergometer sprint kayaking performance.

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Jonathan I. Hochstetler, Anne C. Russ, Ryan Tierney and Jamie L. Mansell

Focused Clinical Question: In athletic training, what is the percentage of workplace bullying compared to the percentage in nursing? Clinical Bottom Line: There is evidence that workplace bullying is prevalent in the athletic training and nursing professions.

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Alex S. Ribeiro, Ademar Avelar, Witalo Kassiano, João Pedro Nunes, Brad J. Schoenfeld, Andreo F. Aguiar, Michele C.C. Trindade, Analiza M. Silva, Luís B. Sardinha and Edilson S. Cyrino

The authors aimed to compare the effects of creatine (Cr) supplementation combined with resistance training on skeletal muscle mass (SMM), total body water, intracellular water (ICW), and extracellular water (ECW) in resistance-trained men as well as to determine whether the SMM/ICW ratio changes in response to the use of this ergogenic aid. Twenty-seven resistance-trained men received either Cr (n = 14) or placebo (n = 13) over 8 weeks. During the same period, subjects performed two split resistance training routines four times per week. SMM was estimated from appendicular lean soft tissue assessed by dual-energy X-ray absorptiometry. Total body water, ICW, and ECW were determined by spectral bioelectrical impedance. Both groups showed improvements (p < .05) in SMM, total body water, and ICW, with greater values observed for the Cr group compared with placebo. ECW increased similarly in both groups (p < .05). The SMM/ICW ratio did not change in either group (p > .05), whereas the SMM/ECW ratio decreased only in the Cr group (p < .05). A positive correlation was observed (p < .05) between SMM and ICW changes (r = .71). The authors’ results suggest that the increase in muscle mass induced by Cr combined with resistance training occurs without alteration of the ratio of ICW to SMM in resistance-trained men.

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Marcelo Danillo Matos dos Santos, Felipe J. Aidar, Raphael Fabrício de Souza, Jymmys Lopes dos Santos, Andressa da Silva de Mello, Henrique P. Neiva, Daniel A. Marinho and Mário C. Marques

Purpose: To verify the effects of using different grip widths in bench press performance in Paralympic powerlifting athletes. Methods: Twelve experienced Paralympic powerlifting male athletes (25.40 [3.30] y, 70.30 [12.15] kg) participated in the study. Maximal dynamic strength and maximal isometric strength (MIS) were determined. Then, mean propulsive velocity (MPV) using 25%, 50%, and 100% of maximal dynamic strength load and time to achieve 30%, 50%, and 100% of MIS were assessed with 4 different grip widths, specifically the biacromial distance (BAD: 42.83 [12.84] cm), 1.3 BAD (55.68 [16.70] cm), 1.5 BAD (63.20 [18.96] cm), and 81 cm. Electromyographic analysis was performed during MIS assessment in the pectoralis major sternal portion, anterior deltoid, triceps brachii long head, and pectoralis major clavicular portion. Results: Large differences were found between MPV performed with different grip widths using 25% of maximal dynamic strength load (P = .02, ηp2=.26). The 1.5 BAD grip tended to show greater force generation and MPV. Moreover, the time needed to achieve 30%, 50%, and 100% of MIS differed between grip widths (P = .03, ηp2=.24), with the lowest values obtained in the 1.5 BAD. Despite the nonstatistical differences that were found, grip widths caused moderate effects on muscle myoelectric activation, showing greater values for pectoralis major clavicular portion and pectoralis major sternal portion, for the 1.3 BAD and 1.5 BAD, respectively. The 1.5 BAD the grip width tended to show greater MPV values and faster contractile responses. Conclusions: These results highlighted the importance of choosing the specific grip width for improvement of performance in Paralympic powerlifting athletes, by increasing velocity of movement and force production in a shorter time, with greater activation of primary muscles.

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Keely Shaw, Jyotpal Singh, Luke Sirant, J. Patrick Neary and Philip D. Chilibeck

Dark chocolate (DC) is high in flavonoids and has been shown to increase nitric oxide in the blood. Increased nitric oxide has the potential to improve delivery of oxygen to muscle, especially in hypoxic conditions, such as altitude. Our aim was to assess the impact of DC supplementation on cycling performance at altitude. Twelve healthy, trained cyclists (n = 2 females, n = 10 males; age = 35 [12] years; height = 177 [7] cm; mass = 75.2 [11.0] kg; VO2max = 55 [6] ml·kg−1·min−1) were randomized to supplement with 60 g of DC or placebo twice per day for 14 days in a double-blind crossover study. After the 2 weeks of supplementation, the participants attended a laboratory session in which they consumed 120 g of DC or placebo and then cycled for 90 min at 50% peak power output, followed immediately by a 10-km time trial (TT) at simulated altitude (15% O2). The plasma concentration of blood glucose and lactate were measured before and at 15, 30, 60, and 90 min during the steady-state exercise and post TT, while muscular and prefrontal cortex oxygenation was measured continuously throughout exercise using near-infrared spectroscopy. DC resulted in a higher concentration of blood glucose (5.5 [0.5] vs. 5.3 [0.9] mmol/L) throughout the trial and lower blood lactate concentration following the TT (7.7 [1.92] vs. 10.0 [4.6] mmol/L) compared with the placebo. DC had no effect on the TT performance (19.04 [2.16] vs. 19.21 ± 1.96 min) or oxygenation status in either the prefrontal cortex or muscle. The authors conclude that, although it provided some metabolic benefit, DC is not effective as an ergogenic aid during TT cycling at simulated altitude.