Department of Exercise Physiology, Faculty of Sport Sciences, Ferdowsi University of Mashhad, Mashhad, Iran.
Hormones (Athens). 2021 Jun;20(2):247-257. doi: 10.1007/s42000-020-00250-6. Epub 2021 Jan 13.
Findings regarding the effects of resistance training (RT) on muscle strength, serum level of IGF-1, and its binding proteins are contradictory. To resolve this contradiction, we performed a systematic review and meta-analysis to investigate the effects of RT on muscle strength, the levels of serum IGF-1, and IGF-binding protein-3 in the elderly and aged.
The PubMed, CINAHL, Medline, Google Scholar, and Scopus databases and reference lists of included studies were systematically searched to identify randomized controlled trials (RCTs) comparing subjects who underwent RT and control individuals up to May 15, 2020. This study was performed following the Preferred Items for Reporting of Systematic Reviews and Meta-Analyses guidelines. We identified and analyzed 11 eligible trials in this meta-analysis.
Pooled data displayed an overall significant elevation in IGF-1 (mean difference (MD): 17.34 ng/ml; 95% confidence interval (CI): 7.23, 27.46) and in muscle strength in leg press (SMD: 0.82; 95% CI: 0.30, 1.34) and bench press (SMD: 0.82; 95% CI: 0.42, 1.23) following RT. By contrast, the pooled estimate showed a non-significant elevation in IGFBP-3 (MD: 0.13 ng/ml; 95% CI: - 39.39, 39.65). Subgroup analysis revealed that the elevation in serum IGF-1 levels after RT was significant only in women (MD: 19.30 ng/ml); moreover, it increased after intervention durations of both > 12 weeks (MD: 21.98 ng/ml) and of ≤ 12 weeks (MD: 15.31 ng/ml).
RT was associated with elevated muscle strength. Moreover, RT was correlated with increased serum levels of IGF-1 among women and among those who received the training for ≤ 12 weeks or > 12 weeks. Further studies are required to elucidate the mechanisms underlying the impact of RT on IGF-1, IGFBP-3, and muscle strength.
关于抗阻训练（RT）对肌肉力量、血清 IGF-1 水平及其结合蛋白的影响的研究结果存在矛盾。为了解决这一矛盾，我们进行了系统评价和荟萃分析，以研究 RT 对老年人和老年人肌肉力量、血清 IGF-1 和 IGF 结合蛋白-3 水平的影响。
系统检索了 PubMed、CINAHL、Medline、Google Scholar 和 Scopus 数据库以及纳入研究的参考文献列表，以确定截至 2020 年 5 月 15 日比较接受 RT 和对照组受试者的随机对照试验（RCT）。本研究遵循系统评价和荟萃分析的首选报告项目指南进行。在这项荟萃分析中，我们确定并分析了 11 项符合条件的试验。
汇总数据显示，IGF-1 总体显著升高（平均差异（MD）：17.34ng/ml；95%置信区间（CI）：7.23，27.46），腿部按压（SMD：0.82；95%CI：0.30，1.34）和卧推（SMD：0.82；95%CI：0.42，1.23）的肌肉力量也得到了提高。相比之下，汇总估计显示 IGFBP-3 水平升高无统计学意义（MD：0.13ng/ml；95%CI：-39.39，39.65）。亚组分析显示，RT 后血清 IGF-1 水平升高仅在女性中具有统计学意义（MD：19.30ng/ml）；此外，干预持续时间大于 12 周（MD：21.98ng/ml）和小于等于 12 周（MD：15.31ng/ml）后均会增加。
RT 与肌肉力量的提高有关。此外，RT 与女性和接受≤12 周或>12 周训练的人群血清 IGF-1 水平升高相关。需要进一步的研究来阐明 RT 对 IGF-1、IGFBP-3 和肌肉力量的影响的机制。
