Resistance training and bone mineral density in rodent models of menopause: review and meta-analysis

The decline in bone mineral density (BMD) is common among older adults, especially due to reduced sex hormone production in women (menopause). Understanding the impact of resistance training on bone tissue is essential for developing effective strategies for the prevention and treatment of this condition. This study investigated the effects of resistance training on BMD in rodent models of osteopenia induced by ovariectomy. The protocol was registered on PROSPERO (CRD42024549460). Inclusion criteria focused on ovariectomized (OVX) female rats and mice engaged in resistance training, with no restrictions on duration, frequency or intensity. A comprehensive search across six databases (and grey literature) identified 314 articles, of which 18 were selected. Resistance training, compared to control groups, significantly increased BMD, particularly in the femur and tibia. The included studies employed various training protocols, such as climbing, jumping and squatting, with variations in training duration and intensity. The meta-analysis demonstrated standardized mean differences of 3.02 (95% confidence interval 1.81-4.24) for climbing and 1.27 (95% confidence interval 0.72-1.82) for jumping protocols, quantifying the extent of improvement in BMD - particularly in the femur and tibia - observed in OVX rodents subjected to resistance training, as compared to sedentary controls. These findings suggest that resistance training positively impacts bone remodeling and may help restore bone microarchitecture in postmenopausal conditions.