Grip Strength Does Not Differ Between Free Weights or Machines in Older Adults: Meta-Analysis

Abstract

Introduction: The aging can lead to low levels of muscle strength, related to the emergence of diseases, physical limitations and an increase in premature death in the elderly. The handgrip strength test is a parameter to measure muscle strength, and strength training with free weights or machines are efficient to increase this outcome. However, these equipments differ in appearance, biomechanics and selection strategy within a periodization, which ends up generating questions in the scientific community regarding which one is more efficient for the outcomes that want to meansure. Objective: This study aimed to compare whether there is a significant difference in handgrip strength in strength training that used free weights or machines in elderly individuals through a systematic review and meta-analysis. Methods: This research followed the protocols and fulfilled all the requirements of Cochrane and The PRISMA Statement. The literature search was performed in the electronic databases Cochrane Library, EMBASE, MEDLINE/PubMed, SCOPUS, Web of Science and Science Direct, and searches were performed in the references of studies already published on the subject. Eligibility criteria included: full articles of clinical trials in English with elderly individuals able to practice physical exercises; interventions with strength training that compared free weights with machines; and assessment of pre- and post-training handgrip strength. Results: A total of 436 studies retrieved from the databases, two studies met the inclusion criteria for performing the systematic review and meta-analysis. Statistical analysis showed no significant difference between groups for handgrip strength (P = 0,56). There was no heterogeneity between the studies (P = 1,00). Conclusion: The conclusion of this study was that there was no significant difference in handgrip strength between strength training using free weights or machines in elderly. Level of Evidence I; Systematic Review and Meta-analysis.