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Martin Buchheit, Ben M. Simpson and Mathieu Lacome

Purpose: To compare between-tests changes in submaximal exercise heart rate (HRex, 3 min, 12 km/h) and the speed associated with 4 mmol/L of blood lactate (V4mmol) in soccer players to get insight into their level of agreement and respective sensitivity to changes in players’ fitness. Methods: A total of 19 elite professional players (23 [3] y) performed 2 to 3 graded incremental treadmill tests (3-min stages interspersed with 1 min of passive recovery, starting speed 8 km/h, increment 2 km/h until exhaustion or 18 km/h if exhaustion was not reached before) over 1.5 seasons. The correlation between the changes in HRex and V4mmol was examined. Individual changes in the 2 variables were compared (>2 × typical error considered “clear”). Results: The changes in HRex and V4mmol were largely correlated (r = .82; 90% confidence interval, .65–.91). In more than 90% of the cases, when a clear individual change in HRex was observed, it was associated with a similar clear change in V4mmol (the same direction, improvement, or impairment of fitness) and conversely. Conclusions: When it comes to testing players submaximally, the present results suggest that practitioners can use HRex or V4mmol interchangeably with confidence. However, in comparison with a field-based standardized warm-up run (3–4 min, all players together), the value of a multistage incremental test with repeated blood lactate samplings is questionable for a monitoring purpose given its time, labor, cost, and poorer player buy-in.

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Jac Orie, Nico Hofman, Laurentius A. Meerhoff and Arno Knobbe

At the Olympic level, optimally distributing training intensity is crucial for maximizing performance. Purpose: The authors evaluated the effect of training-intensity distribution on anaerobic power as a substitute for 1500-m speed-skating performance in the 4 y leading up to an Olympic gold medal. Methods: During the preparation phase of the speed-skating season, anaerobic power was recorded periodically (n = 15) using the mean power (in watts) with a 30-s Wingate test. For each training session in the 4 wk prior to each Wingate test, the volume (in hours), training type (specific, simulation, nonspecific, and strength training), and the rating of perceived exertion (RPE; CR-10) were recorded. Results: Compared with the 8 lowest, the 7 highest-scoring tests were preceded by a significantly (P < .01) higher volume of strength training. Furthermore, the RPE distribution of the number of nonspecific training sessions was significantly different (P < .01). Significant (P < .05) correlations highlighted that a larger nonspecific training volume in the lower intensities RPE 2 (r = .735) and 3 (r = .592) was associated positively and the medium intensities RPE 4 (r = −.750) and 5 (r = −.579) negatively with Wingate performance. Conclusion: For the subject, the best results were attained with a high volume of strength training and the bulk of nonspecific training at RPE 2 and 3, and specifically not at the adjoining RPE 4 and 5. These findings are surprising given the aerobic nature of training at RPE 2 and 3 and the importance of anaerobic capacity in this middle-distance event.

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Fabio Bertapelli, Stamatis Agiovlasitis, Robert W. Motl, Roberto A. Soares, Marcos M. de Barros-Filho, Wilson D. do Amaral-Junior and Gil Guerra-Junior

The purpose of this study was to develop and cross-validate an equation for estimating percentage body fat (%BF) from body mass index and other potential independent variables among young persons with intellectual disability. Participants were 128 persons with intellectual disability (62 women; age 16–24 years) split between development (n = 98) and cross-validation (n = 30) samples. Dual-energy X-ray absorptiometry served as the reference method for %BF. An equation including 1/body mass index and sex (0 = male; 1 = female) was highly accurate in estimating %BF (p < .001; R 2 = .82; standard error of estimate  = 5.22%). Mean absolute and root mean square errors were small (3.1% and 3.9%, respectively). A Bland–Altman plot indicated nearly zero mean difference between actual and predicted %BF with modest 95% confidence intervals. The prediction equation was %BF = 56.708 − (729.200 × [1/body mass index]) + (12.134 × sex). Health care professionals may use the prediction equation for monitoring %BF among young people with intellectual disability.

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Chung-Ju Huang, Hsin-Yu Tu, Ming-Chun Hsueh, Yi-Hsiang Chiu, Mei-Yao Huang and Chien-Chih Chou

This study examined the effects of acute aerobic exercise on sustained attention and discriminatory ability of children with and without learning disabilities (LD). Fifty-one children with LD and 49 typically developing children were randomly assigned to exercise or control groups. The participants in the exercise groups performed a 30-min session of moderate-intensity aerobic exercise, whereas the control groups watched a running/exercise-related video. Neuropsychological tasks, the Daueraufmerksamkeit sustained attention test, and the determination tests were assessed before and after each treatment. Exercise significantly benefited performance in sustained attention and discriminatory ability, particularly in higher accuracy rate and shorter reaction time. In addition, the LD exercise group demonstrated greater improvement than the typically developing exercise group. The findings suggest that the acute aerobic exercise influenced the sustained attention and the discriminatory function in children with LD by enhancing regulation of mental states and allocation of attentional resources.

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Jaap van Dieen

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Giuseppe delli Paoli, Denise van de Laarschot, Edith C.H. Friesema, Remco Verkaik, Antonia Giacco, Rosalba Senese, Pascal P. Arp, P. Mila Jhamai, Stefano M. Pagnotta, Linda Broer, André G. Uitterlinden, Antonia Lanni, M. Carola Zillikens and Pieter de Lange

Fasting enhances the beneficial metabolic outcomes of exercise; however, it is unknown whether body composition is favorably modified on the short term. A baseline–follow-up study was carried out to assess the effect of an established protocol involving short-term combined exercise with fasting on body composition. One hundred seven recreationally exercising males underwent a 10-day intervention across 15 fitness centers in the Netherlands involving a 3-day gradual decrease of food intake, a 3-day period with extremely low caloric intake, and a gradual 4-day increase to initial caloric intake, with daily 30-min submaximal cycling. Using dual-energy X-ray absorptiometry analysis, all subjects substantially lost total body mass (−3.9 ± 1.9 kg; p < .001) and fat mass (−3.3 ± 1.3 kg; p < .001). Average lean mass was lost (−0.6 ± 1.5 kg; p < .001), but lean mass as a percentage of total body mass was not reduced. The authors observed a loss of −3.9 ± 1.9% android fat over total fat mass (p < .001), a loss of −2.2 ± 1.9% gynoid over total fat mass (p < .001), and reduced android/gynoid ratios (−0.05 ± 0.1; p < .001). Analyzing 15 preselected single-nucleotide polymorphisms in 13 metabolism-related genes revealed trending associations for thyroid state–related single-nucleotide polymorphisms rs225014 (deiodinase 2) and rs35767 (insulin-like growth factor1), and rs1053049 (PPARD). In conclusion, a short period of combined fasting and exercise leads to a substantial loss of body and fat mass without a loss of lean mass as a percentage of total mass.

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Alejandro Pérez-Castilla, Ainara Jiménez-Alonso, Mar Cepero, Sergio Miras-Moreno, F. Javier Rojas and Amador García-Ramos

This study explored the impact of different frequencies of knowledge of results (KR) on velocity performance during ballistic training. Fifteen males completed four identical sessions (three sets of six repetitions at 30% one-repetition maximum during the countermovement jump and bench press throw) with the only difference of the KR condition provided: no feedback, velocity feedback after the first half of repetitions of each set (HalfKR), velocity feedback immediately after each repetition (ImKR), and feedback of the average velocity of each set (AvgKR). When compared with the control condition, the ImKR reported the highest velocity performance (1.9–5.3%), followed by the HalfKR (1.3–3.6%) and AvgKR (0.7–4.3%). These results support the verbal provision of velocity performance feedback after every repetition to induce acute improvements in velocity performance.

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Scott Rathwell, Bradley W. Young, Bettina Callary, Derrik Motz, Matt D. Hoffmann and Chelsea Currie

Adult sportspersons (Masters athletes, aged 35 years and older) have unique coaching preferences. No existing resources provide coaches with feedback on their craft with Masters athletes. Three studies evaluated an Adult-Oriented Coaching Survey. Study 1 vetted the face validity of 50 survey items with 12 Masters coaches. Results supported the validity of 48 items. In Study 2, 383 Masters coaches completed the survey of 50 items. Confirmatory factor analysis and exploratory structural equation modeling indicated issues with model fit. Post hoc modifications improved fit, resulting in a 22-item, five-factor model. In Study 3, 467 Masters athletes responded to these 22 items reflecting perceptions of their coaches. Confirmatory factor analysis (comparative fit index = .951, standardized root mean square residual = .036, and root mean square error of approximation = .049) and exploratory structural equation modeling (comparative fit index = .977, standardized root mean square residual = .019, and root mean square error of approximation = .041) confirmed the model. The resultant Adult-Oriented Sport Coaching Survey provides a reliable and factorially valid instrument for measuring adult-oriented coaching practices.

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Teresa Zwierko, Wojciech Jedziniak, Beata Florkiewicz, Halil İbrahim Ceylan, Piotr Lesiakowski, Marta Śliwiak, Marta Kirkiewicz and Wojciech Lubiński

The aim of the study was to explore the functional impairments and related factors in older adults with moderate to advanced stages of glaucoma. Nineteen patients with glaucoma and 19 participants with no ocular disease performed step test and balance control tasks with analysis of overall stability index and fall risk index. Monocular and binocular Humphrey Visual Field tests were used to estimate visual field defect severity. The International Physical Activity Questionnaire was used to measure physical activity level. Patients with glaucoma showed poorer values for most of the mobility and balance control parameters with medium and large effect sizes (0.3–0.5). Mobility scores in patients were partly associated with their monocular visual field defect (rs = .507, p < .05). Low physical activity was identified as a risk factor for falls (rs = −.453, p < .05) and postural instability (rs = −.457, p < .05). Functional declines in dynamic tasks were not related to glaucoma severity. Older adults with glaucoma display impairment with mobility and balance control compared to controls, associated with the degree of monocular visual field loss and lower daily physical activity.