Division of Social and Preventive Medicine, University of Potsdam, Am Mühlenberg 9, 14476, Potsdam, Germany.
Division of Training and Movement Sciences, Research Focus Cognition Sciences, University of Potsdam, Am Neuen Palais 10, Building 12, 14469, Potsdam, Germany.
Sports Med. 2023 Mar;53(3):723-745. doi: 10.1007/s40279-022-01806-9. Epub 2023 Jan 31.
The current literature on the chronic effects of static stretching (SS) exercises on muscle strength and power is unclear and controversial.
We aimed to examine the chronic effects of SS exercises on muscle strength and power as well as flexibility in healthy individuals across the lifespan.
Systematic review with meta-analysis of (randomized) controlled trials.
A systematic literature search was conducted in the databases PubMed, Web of Science, Cochrane Library, and SPORTDiscus up to May 2022.
We included studies that investigated the chronic effects of SS exercises on at least one muscle strength and power outcome compared to an active/passive control group or the contralateral leg (i.e., using between- or within-study designs, respectively) in healthy individuals, irrespective of age, sex, and training status.
The main findings of 41 studies indicated trivial-to-small positive effects of chronic SS exercises on muscle strength (standardized mean difference [SMD] = 0.21, [95% confidence interval 0.10-0.32], p = 0.001) and power (SMD = 0.19, 95% confidence interval 0.12-0.26], p < 0.001). For flexibility, moderate-to-large increases were observed (SMD = 0.96, [95% confidence interval 0.70-1.22], p < 0.001). Subgroup analyses, taking the participants' training status into account, revealed a larger muscle strength improvement for sedentary (SMD = 0.58, p < 0.001) compared with recreationally active participants (SMD = 0.16, p = 0.029). Additionally, larger flexibility gains were observed following passive (SMD = 0.97, p < 0.001) compared with active SS exercises (SMD = 0.59, p = 0.001). The chronic effects of SS on muscle strength were moderated by the proportion of female individuals in the sample (β = 0.004, p = 0.042), with higher proportions experiencing larger gains. Other moderating variables included mean age (β = 0.011, p < 0.001), with older individuals showing larger muscle strength gains, and the number of repetitions per stretching exercise and session (β = 0.023, p = 0.004 and β = 0.013, p = 0.008, respectively), with more repetitions associated with larger muscle strength improvements. Muscle power was also moderated by mean age (β = 0.006, p = 0.007) with larger gains in older individuals. The meta-regression analysis indicated larger flexibility gains with more repetitions per session (β = 0.094, p = 0.016), more time under stretching per session (β = 0.090, p = 0.026), and more total time under stretching (β = 0.078, p = 0.034).
The main findings indicated that chronic SS exercises have the potential to improve muscle strength and power. Such improvements appear to benefit sedentary more than recreationally active participants. Likewise, chronic SS exercises result in a marked enhancement in flexibility with larger effects of passive, as compared with active, SS. The results of the meta-regression analysis for muscle strength indicated larger benefits of chronic SS exercises in samples with higher proportions of female, older participants, and a higher number of repetitions per stretching exercise and session. For muscle power, results suggested larger gains for older participants. Regarding flexibility, findings indicated larger benefits following a higher number of repetitions per exercise and a longer time under stretching per session as well as a longer total time under stretching.
目前关于静态拉伸（SS）练习对肌肉力量和爆发力的慢性影响的文献尚不清楚，存在争议。
我们旨在研究 SS 练习对健康个体整个生命周期内肌肉力量和爆发力以及柔韧性的慢性影响。
系统综述和荟萃分析（随机对照试验）。
系统地检索了 PubMed、Web of Science、Cochrane 图书馆和 SPORTDiscus 数据库中的文献，截至 2022 年 5 月。
我们纳入了研究 SS 练习对至少一项肌肉力量和爆发力结果的慢性影响的研究，与主动/被动对照组或对侧肢体相比（即分别使用组内或组间设计），无论年龄、性别和训练状态如何，均为健康个体。
41 项研究的主要结果表明，慢性 SS 练习对肌肉力量（标准化均数差 [SMD] = 0.21，[95%置信区间 0.10-0.32]，p = 0.001）和爆发力（SMD = 0.19，95%置信区间 0.12-0.26]，p < 0.001）有较小到中等的积极影响。对于柔韧性，观察到适度到较大的增加（SMD = 0.96，[95%置信区间 0.70-1.22]，p < 0.001）。亚组分析考虑了参与者的训练状态，结果表明久坐（SMD = 0.58，p < 0.001）的参与者比休闲活动的参与者（SMD = 0.16，p = 0.029）肌肉力量改善更大。此外，与主动 SS 练习相比，被动 SS 练习（SMD = 0.97，p < 0.001）的柔韧性增益更大（SMD = 0.59，p = 0.001）。SS 对肌肉力量的慢性影响受样本中女性比例的调节（β = 0.004，p = 0.042），女性比例越高，收益越大。其他调节变量包括平均年龄（β = 0.011，p < 0.001），年龄较大的个体肌肉力量增益更大，以及每次拉伸运动和每次拉伸运动的重复次数（β = 0.023，p = 0.004 和 β = 0.013，p = 0.008），重复次数越多，肌肉力量改善越大。肌肉力量也受平均年龄的调节（β = 0.006，p = 0.007），年龄较大的个体肌肉力量增益更大。元回归分析表明，每次拉伸运动的重复次数（β = 0.094，p = 0.016）、每次拉伸运动的伸展时间（β = 0.090，p = 0.026）和总伸展时间（β = 0.078，p = 0.034）增加，柔韧性增益更大。
主要发现表明，慢性 SS 练习有可能改善肌肉力量和爆发力。这种改善似乎对久坐的参与者比对休闲活动的参与者更有益。同样，与主动 SS 相比，慢性 SS 练习会显著增强柔韧性，被动 SS 的效果更大。肌肉力量的元回归分析结果表明，在女性比例、年龄较大的参与者和每次拉伸运动和每次拉伸运动的重复次数较高的样本中，慢性 SS 练习的益处更大。对于肌肉力量，结果表明年龄较大的参与者的收益更大。关于柔韧性，结果表明，每次运动和每次伸展运动的重复次数增加，以及每次伸展运动的伸展时间和总伸展时间增加，都会带来更大的收益。
