Jindo Takashi, Kitano Naruki, Tsunoda Kenji, Kusuda Mikiko, Hotta Kazushi, Okura Tomohiro
1Doctoral Program in Physical Education, Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan. 2Japan Society for the Promotion of Science, Tokyo, Japan. 3Faculty of Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan. 4Physical Fitness Research Institute, Meiji Yasuda Life Foundation of Health and Welfare, Tokyo, Japan. 5Master's Program in Physical Education, Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan. 6Department of Occupational Therapy, Ibaraki Prefectural University of Health Sciences, Ibaraki, Japan.
J Geriatr Phys Ther. 2017 Jul/Sep;40(3):150-157. doi: 10.1519/JPT.0000000000000087.
Decreasing daily life physical activity (PA) outside an exercise program might hinder the benefit of that program on lower-extremity physical function (LEPF) in older adults. The purpose of this study was to investigate how daily life PA modulates the effects of an exercise program on LEPF.
The participants were 46 community-dwelling older adults (mean age, 70.1 ± 3.5 years) in Kasama City, a rural area in Japan. All participated in a fall-prevention program called square-stepping exercise once a week for 11 weeks. We evaluated their daily life PA outside the exercise program with pedometers and calculated the average daily step counts during the early and late periods of the program. We divided participants into 2 groups on the basis of whether or not they decreased PA by more than 1000 steps per day between the early and late periods. To ascertain the LEPF benefits induced by participating in the exercise program, we measured 5 physical performance tests before and after the intervention: 1-leg stand, 5-time sit-to-stand, Timed Up and Go (TUG), habitual walking speed, and choice-stepping reaction time (CSRT). We used a 2-way analysis of variance to confirm the interaction between the 2 groups and the time effect before and after the intervention.
During the exercise program, 8 participants decreased their daily life PA (early period, 6971 ± 2771; late period, 5175 ± 2132) and 38 participants maintained PA (early period, 6326 ± 2477; late period, 6628 ± 2636). Both groups significantly improved their performance in TUG and CSRT at the posttest compared with the baseline. A significant group-by-time interaction on the walking speed (P = .038) was observed: participants who maintained PA improved their performance more than those who decreased their PA.
Square-stepping exercise requires and strengthens dynamic balance and agility, which contributed to the improved time effects that occurred in TUG and CSRT. On the contrary, because PA is positively associated with walking speed, maintaining daily life PA outside an exercise program may have a stronger influence on walking speed. To enhance the effectiveness of an exercise program for young-old adults, researchers and instructors should try to maintain the participant's daily life PA outside the program.
Regardless of decreasing or maintaining daily life PA, the square-stepping exercise program could improve aspects of LEPF that require complex physical performance. However, a greater effect can be expected when participants maintain their daily life PA outside the exercise program.
在锻炼计划之外减少日常生活中的身体活动（PA）可能会阻碍该计划对老年人下肢身体功能（LEPF）的益处。本研究的目的是调查日常生活中的身体活动如何调节锻炼计划对下肢身体功能的影响。
参与者为日本农村地区笠间市的46名社区居住老年人（平均年龄70.1±3.5岁）。所有人都参加了一项名为方步锻炼的预防跌倒计划，每周一次，共11周。我们使用计步器评估他们在锻炼计划之外的日常生活身体活动，并计算该计划早期和晚期的平均每日步数。根据参与者在早期和晚期之间每日步数是否减少超过1000步，将他们分为两组。为了确定参与锻炼计划所带来的下肢身体功能益处，我们在干预前后测量了5项身体性能测试：单腿站立、5次坐立试验、定时起立行走试验（TUG）、习惯步行速度和选择步反应时间（CSRT）。我们使用双向方差分析来确认两组之间的相互作用以及干预前后的时间效应。
在锻炼计划期间，8名参与者减少了他们的日常生活身体活动（早期，6971±2771；晚期，5175±2132），38名参与者维持了身体活动（早期，6326±2477；晚期，6628±2636）。与基线相比，两组在测试后TUG和CSRT的表现均有显著改善。观察到步行速度存在显著的组×时间交互作用（P = 0.038）：维持身体活动的参与者比减少身体活动的参与者表现改善得更多。
方步锻炼需要并增强动态平衡和敏捷性，这有助于改善TUG和CSRT中出现的时间效应。相反，由于身体活动与步行速度呈正相关，在锻炼计划之外维持日常生活中的身体活动可能对步行速度有更强的影响。为了提高针对年轻老年人的锻炼计划的有效性，研究人员和指导者应努力维持参与者在计划之外的日常生活身体活动。
无论日常生活中的身体活动是减少还是维持，方步锻炼计划都可以改善需要复杂身体性能的下肢身体功能方面。然而，当参与者在锻炼计划之外维持他们的日常生活身体活动时，可以预期会有更大的效果。
