Differences in the Impact of Various Types of Exercise on Irisin Levels: A Systematic Review and Meta-Analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of controlled trials
PubMed 38563037 · doi:10.4103/ijpvm.ijpvm_76_23
What was done
A systematic review and meta-analysis of studies evaluating the effect of at least 8 weeks of exercise training versus a passive control group on serum irisin concentrations in overweight and obese adults. Four databases (Google Scholar, Web of Science Core Collection, PubMed, Scopus) were searched. Publication bias was evaluated using Begg and Egger tests.
What was found
From 560 identified records, 7 studies met inclusion criteria. Exercise significantly increased serum irisin compared to passive controls (standardized mean difference [SMD] = 0.957, P = 0.005). High-intensity interval training (HIIT) produced the largest increase (SMD = 1.229, P < 0.001). Subgroup analyses showed significant increases in overweight participants (P < 0.001) but not in obese participants (P = 0.1), in adults under 40 years (P < 0.001) but not over 40 years (P = 0.322), and in men (P < 0.001) but not in women (P = 0.285).
Why it matters
This review indicates that exercise, particularly HIIT, can elevate circulating irisin in overweight adults, though responsiveness may vary markedly by age, sex, and baseline degree of adiposity.
Limits
The total number of included studies is very small (n = 7), and total participant count is not reported in the abstract. The abstract reports publication bias tests rather than comprehensive study-level risk-of-bias assessments, and downstream clinical outcomes (such as sustained weight loss or changes in energy expenditure) were not directly evaluated.
Cited by
- supports Physical exercise stimulates the production of irisin, which causes tissue to burn fuel and generate waste heat.