- 著者
- George K. Beckham Hugh S. Lamont Kimitake Sato Michael W. Ramsey Gregory Haff G. Michael H. Stone
- 出版者
- Active Aging Research Center
- 雑誌
- Journal of Trainology (ISSN:21865264)
- 巻号頁・発行日
- vol.1, no.2, pp.32-35, 2012-11-12 (Released:2015-05-04)
- 参考文献数
- 10
- 被引用文献数
- 22 35
Objectives: To determine if force differences exist between isometric pulling positions corresponding to key positions of the deadlift. Design: Cross-sectional evaluation of isometric strength Methods: 14 powerlifters performed isometric pulls on a force plate at 3 key positions related to the deadlift (at the floor, just above the patella, and 5-6 cm short of lockout) and in the mid thigh pull position (MTP). A 1x4 repeated measures ANOVA was used to ascertain differences between the various pulling positions tested. Bonferroni-adjusted paired samples t-tests were used post-hoc. Results: Forces generated at each bar height were significantly different (F(3,39) = 51.058, p<0.05, η2=0.80). Paired samples t-tests showed significant differences between positions, revealing a trend of greater force generation at increasing heights for positions corresponding to the deadlift. Force generated in the mid thigh pull position was significantly higher than any other position. Conclusion: In positions corresponding to the deadlift, force generation increases at higher bar heights.
- 著者
- Timothy J. Suchomel George K. Beckham and Glenn A. Wright
- 出版者
- Active Aging Research Center
- 雑誌
- Journal of Trainology (ISSN:21865264)
- 巻号頁・発行日
- vol.2, no.2, pp.19-22, 2013-09-25 (Released:2015-05-04)
- 参考文献数
- 14
- 被引用文献数
- 11 28
Objectives: To examine the impact of load on lower body kinetics during the jump shrug. Design: Randomized, repeated measures design. Methods: Fourteen men performed randomized sets of the jump shrug at relative loads of 30%, 45%, 65%, and 80% of their one repetition maximum hang clean (1RM-HC). A number of variables were obtained through analysis of the force-time data, which included peak force, peak velocity, peak power, force at peak power, and velocity at peak power. A series of one-way repeated measures ANOVA were used to compare the differences in peak force, peak velocity, peak power, force at peak power, and velocity at peak power between each load. Results: Statistical differences in peak velocity, peak power, force at peak power, and velocity at peak power existed between loads (p<0.001), while peak force trended toward statistical significance (p=0.060). The greatest peak velocity, peak power, and velocity at peak power occurred at 30% 1RM-HC. In addition the greatest peak force and force at peak power occurred at loads of 65% and 80% 1RM-HC, respectively. Conclusions: Velocity is the greatest contributing factor to peak power production during the jump shrug. Practitioners should prescribe specific loading schemes for the jump shrug to provide optimal training stimuli to their athletes based on the training goal: specifically, loads of 65% 1RM-HC or higher, loads of approximately 30-45% 1RM-HC, and loads of 30% 1RM-HC should be prescribed for improvements in peak force and force at peak power, peak power, and velocity and velocity at peak power, respectively.
- 著者
- Kevin M. Carroll Kimitake Sato George K. Beckham Travis Triplett N. Cameron V. Griggs Michael H. Stone
- 出版者
- Active Aging Research Center
- 雑誌
- Journal of Trainology (ISSN:21865264)
- 巻号頁・発行日
- vol.6, no.1, pp.9-12, 2017-01-26 (Released:2017-04-25)
- 参考文献数
- 16
- 被引用文献数
- 6
Objectives: The purpose of this study was to examine the relationship of velocities in the back squat between one repetition maximum (1RM) and submaximally loaded repetition maximum (RM) conditions, specifically in regard to what has been described as the minimal velocity threshold (MVT). The MVT describes a minimum concentric velocity that an individual must reach or surpass in order to successfully complete a repetition. Design: To test the presence of a MVT, participants were tested for 1RM and RM back squat ability. The mean concentric veloci ties (MCV) of the last successful repetition of each condition were then compared. Methods: Fourteen male participants familiar with the back squat volunteered to participate in the current study (age = 25.0 y ± 2.6, height = 178.9 cm ± 8.1, body mass = 88.2 kg ± 15.8). The mean concentric velocity (MCV) during the last successful repetition from each testing condition was considered for the comparison. Results: Results indicated a non-significant negative relationship of MCV between the 1RM and RM conditions (r = -0.135), no statistical difference between testing conditions (p = 0.266), with a small-to-moderate effect size (d = 0.468). Conclusions: The results of this study suggest that MVT should be further investigated to enhance its use in the practical setting. Additionally, coaches considering using a velocity-based approach for testing athletes should use data from either 1RM or RM conditions, but not both interchangeably. Coaches should be cautious when considering group averages or comparing velocity data between athletes, which may not be appropriate based on our results.