No effect of exercise on insulin-like growth factor IGF1 etc

[Olga]

No effect of exercise on insulin-like growth factor (IGF)-1, insulin and glucose in young women participating in a 16-week randomized controlled trial.
http://www.ncbi.nlm.nih.gov/pubmed/20833973
Arikawa AY, Kurzer M, Thomas W, Schmitz KH.

1Food Science and Nutrition, University of Minnesota.
Abstract

BACKGROUND: Insulin-like growth factor 1 (IGF-1) and IGF binding protein 3 (IGFBP-3) have been associated with increased risk of breast cancer.

METHODS: We report our findings on the effects of 16 weeks of aerobic exercise on IGF axis proteins, insulin, glucose and insulin resistance of 319 young sedentary women. Demographics, health surveys, body composition, dietary intake and blood samples were collected at baseline and 16 weeks. IGF-1 and IGF binding proteins 1, 2, and 3 were measured by ELISA's.

RESULTS: Exercise adherence was 88% and the dropout rates for the exercise and control groups were 21.7% and 14.5%, respectively. There was a small significant change from baseline in IGFBP-3 concentrations. IGFBP-3 levels decreased in controls and increased in exercisers. The between group difference was significant. No other changes were noted.

CONCLUSIONS: This randomized trial suggests that 16 weeks of aerobic exercise, 30 minutes a day, five days a week, has minimal or no effect on levels of insulin, glucose, IGF-1 and IGF binding proteins.