High and low-load resistance training produce similar effects on bone mineral density of middle-aged and older people: A systematic review with meta-analysis of randomized clinical trials.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized clinical trials
PubMed 32454079 · doi:10.1016/j.exger.2020.110973
What was done
This systematic review and meta-analysis searched PubMed/Medline, Scopus, and Web of Science for English-language randomized clinical trials comparing high-load (≥70% 1RM) versus low-load (<70% 1RM) resistance training in middle-aged and older adults (≥45 years old) of both sexes. The primary evaluated outcomes were femoral neck and lumbar spine bone mineral density (BMD).
What was found
From 1,052 retrieved records, 6 studies were included. Meta-analysis showed no significant difference between high-load and low-load training for femoral neck BMD (weighted mean difference [MD] = 0.00 g/cm² [95% CI, -0.01 to 0.01]; P = 0.63; I² = 47%, P = 0.07) or lumbar spine BMD (MD = 0.01 g/cm² [95% CI, -0.00 to 0.02]; P = 0.12; I² = 59%, P = 0.02). Subgroup analysis indicated a small significant benefit favoring high-load training on femoral neck BMD among individuals with normal baseline BMD (MD = 0.01 g/cm² [95% CI, -0.00 to 0.02]; P = 0.04) and in interventions lasting up to 6 months (MD = 0.01 g/cm² [95% CI, -0.00 to 0.02]; P = 0.03).
Why it matters
These findings suggest that low-load resistance training can elicit bone preservation comparable to heavy resistance training in aging populations, offering an alternative for individuals unable to tolerate heavy loads.
Limits
Only six studies met inclusion criteria, and total participant counts were not reported in the abstract. Substantial statistical heterogeneity was observed across analyses (I² = 47% for femoral neck and 59% for lumbar spine). Searches were limited to English-language publications only.
Cited by
- contradicts Resistance training with moderate loads in the 8 to 12 repetition range provides greater bone mineral density benefits than performing high repetitions with light weights.