Evaluation of Peak Power Output in Healthy Adults during Sit-to-Stand and Vertical Jump Assessments

Abstract

ABSTRACT Introduction Measuring maximal, or peak, power output (Pmax) through vertical jumps (VJ) may not be appropriate for all individuals; the sit-to-stand (STS) test could potentially be more functionally relevant for older adults. However, the reliability of measuring Pmax in conjunction with STS and the relationships between Pmax during STS and VJ are unknown. This study aimed to determine the reliability and relationships of Pmax during VJ and STS assessments using a commercially designed testing device. Methods Sixteen healthy males (mean ± standard deviation: age, 24 ± 4 yr; height, 177 ± 7 cm; mass, 86 ± 19 kg) visited the laboratory on two occasions separated by 2–7 d. During each visit, participants performed three maximal STS tests from a table at knee flexions of 90° (STS90) and 120° (STS120) and three countermovement jumps (CMJ) and squat jumps (SJ) in randomized order. Reliability for Pmax during STS and VJ were determined using intraclass correlation coefficients (ICC; model 2,1) and standard errors of the mean (SEM). Systematic variability was examined using separate one-way repeated-measures analyses of variance (ANOVA). Pearson correlation coefficients (r) examined relationships between Pmax as measured during the STS and the VJ. Results ANOVA indicated no systematic variability in Pmax across trials (P > 0.05). ICC and SEM expressed as percentages of the mean ranged from 0.958 to 0.978 and 5.586% to 6.396% for STS and from 0.924 to 0.974 and 4.025% to 6.534% for VJ, respectively. Significant positive relationships were observed between Pmax as measured during STS90, STS120, CMJ, and SJ (r = 0.751–0.962, P ≤ 0.001). Conclusion Results indicate that commercially designed devices may be highly reliable for assessing Pmax during STS and VJ. STS testing is potentially an effective alternative to VJ for assessing lower-body muscle power.