The effect of exercise intervention on IGF axis and metabolic markers regulation in breast cancer patients: a systematic review with pairwise, network, and dose-response meta-analyses

Breast cancer is one of the most common malignancies among women today. Insulin resistance is closely associated with the occurrence and progression of breast cancer. The interplay between the insulin-like growth factor (IGF) axis and metabolic processes plays a critical role in the progression of breast cancer. Moderate exercise interventions can improve the overall health of breast cancer patients by regulating the IGF axis and associated metabolic markers. This study aims to evaluate the effects of various types and doses of exercise on the IGF axis and metabolic in breast cancer patients through pairwise meta-analysis, network meta-analysis (NMA), and dose-response NMA, and to identify the optimal exercise modalities and dosage range. A comprehensive search identified randomized controlled trials (RCTs) for inclusion. Exercise interventions were categorized into continuous aerobic exercise (CAE), combined aerobic and resistance exercise (CE), and resistance exercise (RE). Statistical analyses were conducted on insulin, IGF axis, insulin resistance, and fasting glucose. Dose-response NMA was used to assess the relationship between exercise dose and IGF-1, insulin, and insulin resistance levels. A systematic search of PubMed, Web of Science, and other databases included 26 RCTs with a total of 1803 participants. Exercise significantly reduced IGF-1, insulin, BMI, HOMA-IR, IGFBP-1, triglycerides, and low-density lipoprotein (LDL), while increasing IGFBP and high-density lipoprotein (HDL). Network meta-analysis revealed that CAE was most effective in inhibiting IGF-1 (SUCRA = 81.42), while CE showed the best improvement for insulin (SUCRA = 89.87) and HOMA-IR (SUCRA = 85.77). Dose-response analysis indicated that the recommended exercise dose for breast cancer patients ranged from 560 to 1080 METs·min/week. Specifically, for IGF-1 suppression, CAE with 560–1080 METs·min/week was recommended; for insulin, CE with 460–1400 METs·min/week was optimal; and for HOMA-IR reduction, CE with 460–930 METs·min/week was most effective. Exercise interventions effectively regulate the IGF axis and metabolic markers in breast cancer patients. Continuous aerobic exercise is most effective in reducing IGF-1, while combined aerobic and resistance exercise is more advantageous for improving insulin levels and insulin resistance.