RESUMO
ABSTRACT: Calaway, C, Mishra, S, Parrino, R, Martinez, KJ, Mann, JB, and Signorile, JF. Velocity-based training affects the load-velocity relationship in leg press and chest press for older persons. J Strength Cond Res XX(X): 000-000, 2024-This study examined the impact of 3 months of velocity-based training (VBT) on chest press (CP) and leg press (LP) maximal strength (1 repetition maximum [1RM]), peak power (PP), and percentage load where PP was achieved (%1RMPP) in older adults. Twenty-nine subjects were assigned to either a velocity-deficit (VD) group or a force-deficit (FD) group for each exercise depending on their load-velocity (LV) curves. Changes in load were determined by the ability to maintain either 90% (VD) or 70% (FD) of their PP during training. Subjects' powers were tested before and after the training intervention at loads between 40 and 80%1RM. Separate 2 (group) × 2 (time) ANOVA was used to examine changes in each variable by group for each exercise. Wilcoxon signed-rank tests were used to determine whether significant changes in %1RMPP for each exercise and group. For chest press 1 repetition maximum, there were no significant main effects or interaction. Significant main effects for time were observed for leg press 1 repetition maximum (p < 0 .001, η2 = 0.547) and chest press peak power (p = 0.009, η2 = 0.243). For LPPP, there were no significant main effects or interactions. For %1RMPP, CP median scores revealed no significant changes for either group. Significant declines in %1RMPP were observed for leg press velocity-deficit and leg press force-deficit (p < 0.03) groups. Velocity-based training was effective at improving 1RM, PP, and shifting %1RMPP in the LP groups. These results have implications for targeting power improvements at specific areas of the LV curve. Health care providers and trainers should consider these findings when constructing exercise programs to counter age-related declines in older adults.
RESUMO
ABSTRACT: Parrino, RL, Martinez, KJ, Konlian, JA, Conti, JM, and Signorile, JF. Leg press and chest press power normative values by half decade in older women. J Strength Cond Res 38(5): 991-998, 2024-Neuromuscular power is essential for the performance of most activities of daily living and the maintenance of functional independence throughout the aging process. Power declines rapidly in later life; however, this decline may be reduced or delayed with early detection and intervention. Therefore, this study provides leg press and chest press power normative values for older women. Women's power data for this analysis included 229 participants, 60-90 years of age. Power testing was conducted on Keiser A420 pneumatic leg press and chest press machines following a standardized protocol. Data were stratified into half-decade age groups and analyzed using a 1-way ANOVA. Descriptive statistics and quartile rankings are reported, and significant differences between age groups are outlined. There were significant differences in absolute and relative leg press peak power between the age groups ( p < 0.05). However, there were no significant differences in absolute or relative chest press peak power between the age groups. This research established normative values and quartile rankings for leg press and chest press power in older women 60-90 years of age, allowing comparative evaluations with patients and subjects by clinicians and researchers, respectively. These values should improve exercise interventions designed to improve power production by providing assessments of subjects' current status and allowing comprehensive monitoring of progress.
