Prolonged treadmill training is not able to prevent ovariectomy-induced bone loss

Area of Science:

• Bone biology and osteoporosis research
• Exercise physiology
• Gerontology

Background:

• Osteoporosis is a significant health concern, particularly postmenopause.
• Exercise is a known prophylaxis for osteoporosis, but optimal regimens are unclear.
• Ovariectomy (OVX) in mice is a standard model for postmenopausal bone loss.

Purpose of the Study:

• To evaluate the efficacy of different treadmill exercise regimens in preventing bone loss in OVX mice.
• To determine if axial loading and tensile strain from treadmill exercise can ameliorate osteoporosis.

Main Methods:

• Ovariectomized (OVX) and sham-operated mice underwent 14 weeks of treadmill training (constant speed, incline/decline, or interval training).
• Bone structure was assessed using micro-computed tomography (μCT).
• Biomechanical stability, muscle volume (MRI), and bone turnover markers (ELISA) were measured.

Main Results:

• OVX induced bone mass loss and decreased stability, with a transient increase in PINP.
• All exercise regimens increased muscle volume and running velocity.
• No exercise program effectively prevented OVX-induced bone loss.

Conclusions:

• Treadmill exercise alone, including varied inclines and interval training, is insufficient to prevent postmenopausal osteoporosis in this mouse model.
• Axial loading and tensile strain may not be adequate for osteoporosis prophylaxis.
• Combined therapeutic strategies, potentially including pharmaceuticals or supplements, may be necessary to complement exercise for effective osteoporosis prevention.