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Megan Q. Beard, Samantha A. Boland and Phillip A. Gribble

Decreased hip strength is often present in patients with chronic overuse lower extremity injuries. The hand-held dynamometer (HHD) can be used in a clinical setting to quantify hip strength; however, reliability of the device remains unclear. The purpose of this study was to determine the interexaminer and intersession reliability of a HHD when measuring isometric hip abduction (HABD) and external rotation (HER) strength, both with and without a fixed strap. The HHD had good to high reliability regardless of examiner, session, or stabilization when measuring HABD (ICC = 0.885–0.977) and HER (ICC = 0.879–0.958) isometric strength. HHD is an appropriate instrument for measuring isometric hip strength.

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Andrea Nicolò, Marco Montini, Michele Girardi, Francesco Felici, Ilenia Bazzucchi and Massimo Sacchetti

Purpose: Variables currently used in soccer training monitoring fail to represent the physiological demand of the player during movements like accelerations, decelerations, and directional changes performed at high intensity. We tested the hypothesis that respiratory frequency (f R) is a marker of physical effort during soccer-related high-intensity exercise. Methods: A total of 12 male soccer players performed a preliminary intermittent incremental test and 2 shuttle-run high-intensity interval training (HIIT) protocols, in separate visits. The 2 HIIT protocols consisted of 12 repetitions over 9 minutes and differed in the work-to-recovery ratio (15:30 vs 30:15 s). Work rate was self-paced by participants to achieve the longest possible total distance in each HIIT protocol. Results: Work-phase average metabolic power was higher (P < .001) in the 15:30-second protocol (31.7 [3.0] W·kg−1) compared with the 30:15-second protocol (22.8 [2.0] W·kg−1). Unlike heart rate and oxygen uptake, f R showed a fast response to the work–recovery alternation during both HIIT protocols, resembling changes in metabolic power even at supramaximal intensities. Large correlations (P < .001) were observed between f R and rating of perceived exertion during both 15:30-second (r = .87) and 30:15-second protocols (r = .85). Conclusions: Our findings suggest that f R is a good marker of physical effort during shuttle-run HIIT in soccer players. These findings have implications for monitoring training in soccer and other team sports.

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Ramesh Kaipa, Bethany Howard, Roha Kaipa, Eric Turcat and Laurielle Prema

The current study compared the role of massed versus distributed practice in learning novel foreign language utterances. Fifty healthy native English-speaking participants were randomly assigned to either massed or distributed practice groups. All participants practiced eight novel French utterances 25 times each for a total of 200 times, with the spacing of practice sessions differing between the two groups. Both the groups completed an immediate retention as well as a delayed retention test. Participants’ learning was evaluated based on phonetic accuracy and naturalness of the French utterances. The findings revealed that participants involved in distributed practice demonstrated better learning over participants involved in massed practice. Future research should aim to extrapolate these findings in treating speech disorders.

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Megan Chawansky

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Nima Dehghansai and Joseph Baker

Initiatives have been designed to attract novice athletes and to enable transfer for experienced athletes. However, the authors have very little knowledge of the effectiveness of these programs. To further improve our understanding, this study explored the demographic and sporting careers of 225 participants attending one of the 10 Paralympian Search events held between 2016 and 2018. The sample consisted of participants with a wide range of impairments and sport experiential backgrounds. The majority of the participants reported having some experience in sports, suggesting that either the promotions reached athletes involved in sports already or the advertising appealed especially to this cohort. Athletes with impairments acquired at various stages of their lives (congenital, before adolescence, adolescence, early adulthood, and adulthood) displayed differences in their sporting trajectories, suggesting considerations for current developmental models. Furthermore, it should be considered to vary the testing locations of future events to increase the reach to rural areas and implement new methods to attract novice participants.

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Paddy C. Dempsey, Chuck E. Matthews, S. Ghazaleh Dashti, Aiden R. Doherty, Audrey Bergouignan, Eline H. van Roekel, David W. Dunstan, Nicholas J. Wareham, Thomas E. Yates, Katrien Wijndaele and Brigid M. Lynch

Background: Recent updates to physical activity guidelines highlight the importance of reducing sedentary time. However, at present, only general recommendations are possible (ie, “Sit less, move more”). There remains a need to investigate the strength, temporality, specificity, and dose–response nature of sedentary behavior associations with chronic disease, along with potential underlying mechanisms. Methods: Stemming from a recent research workshop organized by the Sedentary Behavior Council themed “Sedentary behaviour mechanisms—biological and behavioural pathways linking sitting to adverse health outcomes,” this paper (1) discusses existing challenges and scientific discussions within this advancing area of science, (2) highlights and discusses emerging areas of interest, and (3) points to potential future directions. Results: A brief knowledge update is provided, reflecting upon current and evolving thinking/discussions, and the rapid accumulation of new evidence linking sedentary behavior to chronic disease. Research “action points” are made at the end of each section—spanning from measurement systems and analytic methods, genetic epidemiology, causal mediation, and experimental studies to biological and behavioral determinants and mechanisms. Conclusion: A better understanding of whether and how sedentary behavior is causally related to chronic disease will allow for more meaningful conclusions in the future and assist in refining clinical and public health policies/recommendations.

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Krista Schroeder, Martha Y. Kubik, Jiwoo Lee, John R. Sirard and Jayne A. Fulkerson

Background: Youth experience a decrease in physical activity (PA) and an increase in sedentary time during adolescence. Better understanding of factors associated with activity levels during preadolescence may inform interventions to minimize decline. This study compared the association of self-efficacy for PA, parent support for PA, and peer support for PA with moderate-to-vigorous PA (MVPA) and sedentary time among 8- to 12-year-old children with body mass index ≥75th percentile. Methods: This study analyzed baseline data from a school-based healthy weight management intervention trial, conducted in metropolitan Minnesota. Self-efficacy for PA, parent support for PA, and peer support for PA were measured by child survey using reliable tools. MVPA and sedentary time were measured using accelerometer. Results: Participants included 114 children; mean age was 9.4 (0.9) years, 51% were females, 55% received public assistance, and 57% were racial/ethnic minorities. Self-efficacy for PA was positively associated with moderate to vigorous PA for girls (β = 1.83, P < .01) and inversely with sedentary time for the total sample (β = −7.00, P = .03). Parent support for PA was positively associated with sedentary time for girls (β = 9.89, P = .04) and the total sample (β = 7.83, P = .04). Conclusions: Interventions for preadolescents with elevated body mass index may improve activity levels by increasing self-efficacy for PA.

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Yuko Kuramatsu, Yuji Yamamoto and Shin-Ichi Izumi

This study investigated the sensorimotor strategies for dynamic balance control in individuals with stroke by restricting sensory input that might influence task accomplishment. Sit-to-stand movements were performed with restricted vision by participants with hemiparesis and healthy controls. The authors evaluated the variability in the position of participants’ center of mass and velocity, and the center-of-pressure position, in each orthogonal direction at the lift-off point. When vision was restricted, the variability in the mediolateral center-of-pressure position decreased significantly in individuals with hemiparesis, but not in healthy controls. Participants with hemiparesis adopted strategies that explicitly differed from those used by healthy individuals. Variability may be decreased in the direction that most requires accuracy. Individuals with hemiparesis have been reported to have asymmetrical balance deficits, and that meant they had to prioritize mediolateral motion control to prevent falling. This study suggests that individuals with hemiparesis adopt strategies appropriate to their characteristics.

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Kelly A. Brock, Lindsey E. Eberman, Richard H. Laird IV, David J. Elmer and Kenneth E. Games

Context: Several interventions are available to reduce the intensity and duration of the unwanted effects (eg, muscle soreness) associated with physical activity, such as massage, compression garments, and sequential pulse compression (SPC). Such interventions aim to increase blood flow to alleviate symptoms. However, there is a lack of evidence to support the use of SPC to alter total hemoglobin concentration (THb) in active individuals. Objective: To examine the acute effects of a single session of SPC on hemoglobin concentration compared with a control condition. Design: Single cohort, crossover design. Participants: Thirty-four physically active and healthy participants (females = 12 and males = 22) completed the study. Interventions: The authors randomly assigned participants to first receive the experimental (SPC) or control condition. Measures were recorded precondition and postcondition. Participants returned to the laboratory to complete the second condition ≥24 hours after the first condition. Main Outcome Measures: Relative changes in THb, deoxygenated hemoglobin, and oxygenated hemoglobin measures were recorded using near-infrared spectroscopy placed on the muscle belly of the medial gastrocnemius of the dominant limb. Results: SPC significantly increased THb (P < .001, d = 0.505) and oxygenated hemoglobin (P < .001, d = 0.745) change scores compared with the control condition. No statistical difference in deoxygenated hemoglobin change scores was found between the SPC and control conditions, but a medium effect size suggests potential biological significance (P = .06, d = 0.339). Conclusions: Overall, SPC increases THb to the lower-extremity and may be a viable option in the management of muscle soreness related to physical activity.

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Lauren C. Hindman and Nefertiti A. Walker

Women remain the minority in sport organizations, particularly in leadership roles, and prior work has suggested that sexism may be to blame. This study examines women’s experiences of both overt and subtle sexism in the sport industry as well as the impact such experiences have on their careers. Based on interviews and journal entries from women managers working in a men’s professional sports league, the findings suggest that the culture of sport organizations perpetuates sexism, including the diminishment and objectification of women. Sexism occurs in women’s everyday interactions with their supervisors and coworkers, as well as others that they interact with as part of their jobs. Such experiences result in professional and emotional consequences, which women navigate by employing tactics that enable their survival in the sport industry.