抗阻训练对衰弱老年人肌力和体适能的剂量效应关系研究

Study on the dose response relationship of resistance training on muscle strength and physical fitness of the frail elderly

目的探讨抗阻训练对衰弱老年人肌力和体适能的剂量效应关系。方法选取2021年1—12月北京市朝阳区某四星级养老机构长期入住的衰弱老年人,采用随机数字表法分为中量小强度组、中量中强度组、中量大强度组、大量小强度组、大量中强度组、大量大强度组和对照组。对照组给予常规照护,6个干预组在对照组基础上分别给予为期12周的不同运动强度和运动量的下肢抗阻训练,在干预前、干预6周和12周时采用肌力测量仪评估下肢肌力,使用体适能测试评估体适能。结果本研究共招募老年受试者161人,分为6个干预组和1个对照组,每组23人,干预过程中无脱落患者。混合线性模型评估纵向重复测量数据的主效应(时间、分组)分析显示,①下肢肌力:干预前与干预中、干预前与干预后、干预中与干预后比较,中量中强度组与中量小强度组、中量大强度组与中量小强度组、中量小强度组与对照组比较,差异均有统计学意义(P<0.001);②6 min步行测试:干预中与干预后比较,中量中强度组与中量大强度组、中量大强度组与大量大强度组、中量大强度组与中量小强度组、中量小强度组与对照组比较,差异均有统计学意义(P<0.001);③30 s坐站测试:干预前与干预后、干预中与干预后比较,中量中强度组与中量大强度组、中量大强度组与大量大强度组、中量大强度组与中量小强度组、中量小强度组与对照组比较,差异均有统计学意义(P<0.001);④8英尺起立行走测试:中量中强度组与中量大强度组、中量大强度组与大量大强度组、中量大强度组与中量小强度组、大量小强度组与大量中强度组、大量小强度组与对照组比较,差异均有统计学意义(P<0.001)。抗阻训练的运动量与衰弱老年人下肢肌力、30 s坐站测试及6 min步行测试结果存在线性趋势,抗阻训练的运动强度与衰弱老年人的下肢肌力和6 min步行测试结果存在线性趋势。结论抗阻训练与衰弱老年人的肌力和体适能存在剂量效应关系。中等及以上运动强度或中等运动量的运动训练可为衰弱老年人肌力和体适能的改善带来较大效益,同时小强度及小运动量的训练也可产生积极的健康效应。

Objective To explore the dose response relationship of resistance training on muscle strength and physical fitness of the frail elderly.Methods The frail elderly who lived in a four-star nursing home institution in Chaoyang District of Beijing from January to December 2021 were selected and divided into medium amount and low intensity group,medium amount and moderate intensity group,medium amount and high intensity group,large amount and low intensity group,large amount and moderate intensity group,large amount and high intensity group and the control group by random number table method.The control group was given routine care,and the six intervention groups were given lower limb resistance training with different exercise intensity and amount for 12 weeks on the basis of the control group.The myosthenometer was used to quantify the lower limb muscle strength,and the senior fitness test(SFT)was used to evaluate physical fitness of the elderly before intervention,6 weeks and 12 weeks of intervention.Results A total of 161 elderly subjects were recruited and divided into six intervention groups and one control group,with 23 subjects in each group.There was no dropout during the intervention.The main effect(time,grouping)analysis of the longitudinal repeated measurement data assessed by the mixed linear model showed that:(1)Lower limb muscle strength:there were statistically significant differences between before and during intervention,before and after intervention,during and after intervention,the comparison also showed that the differences were statistically significant between the medium amount and moderate intensity group and medium amount and low intensity group,medium amount and high intensity group and medium amount and low intensity group,medium amount and low intensity group and control group(P<0.001).(2)6-minutes walk test:there were statistically significant differences between during and after intervention,the comparison also showed that the differences were statistically significant between medium amount and moderate intensity group and medium amount and high intensity group,medium amount and high intensity group and large amount and high intensity group,medium amount and high intensity group and medium amount and low intensity group,medium amount and low intensity group and control group(P<0.001).(3)30-seconds sit-stand test:there were statistically significant differences between before and after intervention,during and after intervention;the comparison also showed that the differences were statistically significant between medium amount and moderate intensity group and medium amount and high intensity group,medium amount and high intensity group and large amount and high intensity group,medium amount and high intensity group and medium amount and low intensity group,medium amount and low intensity group and control group(P<0.001).(4)8-feet up and go test:the comparison showed that the differences were statistically significant between medium amount and moderate intensity group and medium amount and high intensity group,medium amount and high intensity group and large amount and high intensity group,medium amount and high intensity group and medium amount and low intensity group,large amount and low intensity group and large amount and moderate intensity group,large amount and low intensity group and control group(P<0.001).There was a linear trend between the exercise amount of resistance training and the lower limb muscle strength,the results of 30-seconds sit-stand test and 6-minutes walk test of the frail elderly.There was a linear trend between the exercise intensity of resistance training and the lower limb muscle strength and 6-minutes walk test results of the frail elderly.Conclusions There is a dose response relationship between resistance training and muscle strength,physical fitness of the frail elderly.The exercise with moderate and above intensity or the exercise with medium amount can bring great benefits to improve muscle strength and physical fitness of the frail elderly.Meanwhile,the exercise with low intensity and small amount of exercise can also produce positive health effects.