Adkinsyates9014

Morris, CG, Weber, JA, and Netto, KJ. Relationship between mechanical effectiveness in sprint running and force-velocity characteristics of a countermovement jump in Australian rules football athletes. J Strength Cond Res XX(X) 000-000, 2020-This study evaluated the mechanical determinants of 40-m sprint performance in elite Australian Rules Football (ARF) athletes and identified variables of countermovement jumps (CMJs) that related to the sprint. Fourteen elite male ARF athletes (age = 22.7 ± 3.6 years; height = 1.88 ± 0.08 m; mass = 88.2 ± 9.38 kg) completed two 40-m sprints and 3 CMJs. Sprint mechanics were calculated using inverse dynamic methods from sprint times, anthropometric and spatiotemporal data, whereas CMJ variables were obtained from in-ground force plates. Associations between sprint mechanics, sprint performance, and CMJ variables were identified using Pearson's correlation coefficient. A p-value of less then 0.036 was considered statistically significant for all analyses after performing Brunning velocity ability. Furthermore, associations between CMJ variables and sprint performance provide practitioners with an approach to assess sprint performance in-season, monitor training adaptations and further individualize training interventions, without requiring maximal sprint testing.Bellicha, A, Giroux, C, Ciangura, C, Menoux, D, Thoumie, P, Oppert, J-M, and Portero, P. Vertical jump on a force plate for assessing muscle strength and power in women with severe obesity reliability, validity, and relations with body composition. see more J Strength Cond Res XX(X) 000-000, 2020-Muscle strength and power, particularly when assessed during multijoint movements such as vertical jump (VJ), are important predictors of health status and physical function. Vertical jump is mainly used in athletes, also in untrained or older adults, but has not yet been used in subjects with obesity. We aimed to assess the following in this population (a) the reliability of VJ parameters, (b) their validity compared with isokinetic testing, and (c) their relations with body composition. In 20 women with severe obesity (mean [SD] age 41.1 [11.6] years; body mass index 43.9 [4.4] kg·m) without severe orthopedic disorders, VJ parameters, knee extension torque, and body composition were assessed using a force plate, an isokinetic dynamometer, and dual-energy x-ray absorptiometry, respectively. Excellent reliability was found for absolute peak power and peak force in VJ (intraclass correlation coefficient [95% confidence interval] 0.95 [0.88-0.98] and 0.90 [0.77-0.96], respectively), and moderate to good validity of peak power and peak force compared with isokinetic torque (r = 0.79 and r = 0.67, respectively; all p less then 0.01). Positive relations were found between peak force and peak power during VJ and lean body mass (r = 0.89 and r = 0.60, respectively; p less then 0.01) and a negative relation was found between peak velocity or VJ height and fat mass (r = -0.65 and -0.64, respectively; p less then 0.01). These results suggest that VJ on a force plate is a reliable and valid test for assessing muscle strength and power in severely obese subjects. Vertical jump testing is easy to implement, which can facilitate its use in both research and clinical testing in this setting (ClinicalTrials.govID NCT03325764).Legerlotz, K, Kittelmann, J, Dietzel, M, Wolfarth, B, and Böhlke, N. Ice hockey-specific repeated shuttle sprint test performed on ice should not be replaced by off-ice testing. J Strength Cond Res XX(X) 000-000, 2020-Although the importance of sport-specific testing has been stated in various studies, the application of standard tests that are little related to the requirements in competition is still widespread in performance diagnostics. Furthermore, the actual exercise mode in testing often deviates from the exercise mode in competition. The aim of this study was therefore to investigate how the performance in an ice hockey mimicking repeated sprint shuttle test conducted off-ice (RSS) differs from the on-ice performance (RISS). The two performance tests were completed by 21 male junior ice hockey players within one week. Anaerobic fatigue was significantly larger in RISS and did not correlate with RSS, whereas best run, mean run, total run time, turn and fly time, and total times in all three shifts correlated moderately. Although the best and mean run times did not differ, these times were achieved with different strategies depending on the test condition, indicated by significantly different split times. Aerobic fatigue in shift 3 was the only parameter where the off-ice measurement correlated strongly with the on-ice measurement. Our results imply that an off-ice test does not predict on-ice performance with sufficient precision, strongly advocating performance testing in the exercise mode used in competition.Roberts, BM, Nuckols, G, and Krieger, JW. Sex differences in resistance training A systematic review and meta-analysis. J Strength Cond Res XX(X) 000-000, 2020-The purpose of this study was to determine whether there are different responses to resistance training for strength or hypertrophy in young to middle-aged males and females using the same resistance training protocol. The protocol was pre-registered with PROSPERO (CRD42018094276). Meta-analyses were performed using robust variance random effects modeling for multilevel data structures, with adjustments for small samples using package robumeta in R. Statistical significance was set at P less then 0.05. The analysis of hypertrophy comprised 12 outcomes from 10 studies with no significant difference between males and females (effect size [ES] = 0.07 ± 0.06; P = 0.31; I = 0). The analysis of upper-body strength comprised 19 outcomes from 17 studies with a significant effect favoring females (ES = -0.60 ± 0.16; P = 0.002; I = 72.1). The analysis of lower-body strength comprised 23 outcomes from 23 studies with no significant difference between sexes (ES = -0.21 ± 0.16; P = 0.20; I = 74.7). We found that males and females adapted to resistance training with similar effect sizes for hypertrophy and lower-body strength, but females had a larger effect for relative upper-body strength. Given the moderate effect size favoring females in the upper-body strength analysis, it is possible that untrained females display a higher capacity to increase upper-body strength than males. Further research is required to clarify why this difference occurs only in the upper body and whether the differences are due to neural, muscular, motor learning, or are an artifact of the short duration of studies included.