Objective: In adults, skeletal muscle insulin sensitivity (SI ) and fatty acid oxidation (FAO) are linked with a predisposition to obesity. The current study aimed to determine the effects of maternal exercise on a model of infant skeletal muscle tissue (differentiated umbilical cord mesenchymal stem cells [MSCs]) SI and FAO and analyzed for associations with infant body composition.
Methods: Females <16 weeks' gestation were randomized to either 150 min/wk of moderate-intensity aerobic, resistance, or combination exercise or a nonexercising control. At delivery, MSCs were isolated from umbilical cords and myogenically differentiated, and SI and FAO were measured using radiolabeled substrates. Infant body fat percentage (BF%) and fat-free mass were calculated using standard equations at 1 and 6 months of age.
Results: MSCs from infants of all exercisers had significantly (p < 0.05) higher SI . MSC SI was inversely associated with infant BF% at 1 (r = -0.38, p < 0.05) and 6 (r = -0.65, p < 0.01) months of age. Infants with high SI had lower BF% at 1 (p = 0.06) and 6 (p < 0.01) months of age. MSCs in the high SI group had higher (p < 0.05) FAO.
Conclusions: Exposure to any type of exercise in utero improves offspring SI and could reduce adiposity in early infancy.
Trial registration: ClinicalTrials.gov NCT03838146.
© 2023 The Authors. Obesity published by Wiley Periodicals LLC on behalf of The Obesity Society.