Exercise-induced modulation of IGF-1 in healthy, obese, and cancer populations: a systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 41250619 · doi:10.1080/07853890.2025.2586331
What was done
PubMed and Embase were searched through July 2024 for randomized controlled trials (RCTs) evaluating chronic exercise interventions (≥8 weeks) versus non-exercise controls on serum IGF-1 levels in adults (≥18 years). Trials combining exercise with medications, hormone therapy, or structured dietary interventions were excluded. Meta-analysis was performed using weighted mean differences (WMD) with 95% confidence intervals across healthy individuals, individuals with obesity, and cancer patients or survivors, with trial sequential analysis used to assess robustness.
What was found
Twenty-one RCTs with 1,376 participants were analyzed: - Exercise increased IGF-1 in healthy individuals: WMD = 21.41 (95% CI 8.01 to 34.81). - In individuals with obesity: WMD = 15.46 (95% CI -1.07 to 31.99). - In cancer patients or survivors, exercise reduced IGF-1: WMD = -14.71 (95% CI -19.77 to -9.65). - Exercise increased IGFBP-3 in both healthy and cancer populations among studies reporting both markers.
Why it matters
This review demonstrates that the endocrine response to exercise is population-dependent, increasing circulating IGF-1 in healthy adults while reducing it in cancer patients and survivors.
Limits
Measurement units for IGF-1 values were omitted from the abstract. The confidence interval for the obesity group crossed zero despite text describing a significant increase. Specific exercise modalities, intensities, adherence, and cancer stages/types were not detailed in the abstract.
Cited by
- contradicts Acute aerobic exercise lowers circulating serum IGF-1 in humans.