Objectives

Lower body power declines with age and is associated with decreased physical function in older adults. However, the majority of the tools available to measure power are expensive and require considerable space and expertise to operate. The purpose of this study was to assess the validity, reliability, and measurement error of a sit-to-stand power test (STSp) to assess lower body power.

Methods

51 community-dwelling adults, 65 years or older, completed a power test using a pneumatic leg press (LP), the Short Physical Performance Battery (SPPB) that includes a test of balance, usual walking speed, and chair stand tests; Timed Up and Go (TUG) test at both usual and fast paces, and Patient-Reported Outcome Measures (PROMs). A two-week test-retest assessed the reliability in 36 participants. The study hypotheses and analysis were pre-registered prior to data collection and statistical analyses were blinded.

Results

The mean age was 71.3 years, with 63% females, and an average SPPB score of 10.6 (median = 12). STSp peak power was strongly correlated with LP (r = 0.90, 95% CI (0.82, 0.94). As hypothesized, the STSp peak power showed similar or higher correlations with physical function tests relative to LP peak power: SPPB (0.41 vs. 0.29), chair stand test (−0.44 vs. -0.35), TUG test at usual pace (−0.37 vs. −0.29) and fast pace (−0.41 vs. −0.34) and balance (0.33 vs. 0.22), but not for mobility (0.34 vs. 0.38) and function (0.41 vs. 0.48) questionnaire. For discriminant validity, as hypothesized, males showed higher STSp peak power compared to females (Δ = 492 W, p < .001, Cohen's d = 2.0). Test-retest assessment yielded an intraclass correlation coefficient of 0.96 and a standard error of measurement of 70.4 W. No adverse events were reported or observed for both tests.

Conclusion

The STSp showed adequate validity and reliability in measuring lower body power in community-dwelling older adults. The test is quick, relatively inexpensive, safe, and portable and thus should be considered for use in aging research.

中文翻译：

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老年人坐坐式功率测试的有效性，可靠性和测量误差：一项预先注册的研究

目标

较低的体力会随着年龄的增长而下降，并与老年人的身体机能下降有关。但是，大多数可用于测量功率的工具都很昂贵，并且需要相当大的空间和专业知识才能操作。这项研究的目的是评估坐下站立式功率测试（STSp）评估下半身功率的有效性，可靠性和测量误差。

方法

51名65岁或65岁以上的社区成年人，使用气压腿压（LP），短物理性能电池（SPPB）完成了功率测试，其中包括平衡测试，通常的步行速度和座椅站立测试；定时和按时（TUG）测试以及常规和快速步调，以及患者报告的结果测量（PROM）。为期两周的重新测试评估了36位参与者的可靠性。在数据收集之前对研究假设和分析进行了预先注册，并对统计分析进行了盲目处理。

结果

平均年龄为71.3岁，女性为63％，SPPB平均得分为10.6（中位数= 12）。STSp峰值功率与LP密切相关（r  = 0.90，95 ％CI（0.82，0.94）。假设，STSp峰值功率与物理功能测试相对于LP峰值功率显示相似或更高的相关性：SPPB（0.41 vs. 0.29 ），椅子站立测试（-0.44对-0.35），TUG测试以通常的速度（-0.37对-0.29）和快节奏（-0.41对-0.34）和平衡（0.33对0.22）进行，但不适用于流动性（0.34 vs. 0.38）和功能（0.41 vs. 0.48）问卷调查表，对于可区分的效度，如假设的，男性表现出比女性更高的STSp峰值功率（Δ= 492 W，p <.001，科恩的d = 2.0）。重测后评估得出的组内相关系数为0.96，测量的标准误为70.4W。两种测试均未报告或观察到不良事件。

结论

STSp在测量社区居民老年人的下肢力量方面显示出足够的有效性和可靠性。该测试快速，相对便宜，安全且便携，因此应考虑用于老化研究。