The importance of physical activity in osteoporosis. From the molecular pathways to the clinical evidence

Osteoporosis is a very common bone disorder characterized by low bone mass and signs of deterioration, responsible for bone fragility typical in this pathology. The risk factors for the onset of osteoporosis are many and different from each other. Some of them cannot be modified, such as age, hereditary diseases and endocrine diseases. Others are modifiable, so that prevention is an advisable tool to reduce the incidence of osteoporosis. Among preventive tools, physical activity is certainly a valid instrument of prevention, in fact physical activity contributes to a healthy energy balance and increases muscle mass and bone mass. In the present narrative review, we wanted to pay attention to the possible influence of physical activity on the pathophysiological molecular pathways of osteoporosis and to the use of different exercise training in treatment of osteoporosis. From the literature analyzed, in relation to the effects of physical activity on bone metabolism, it is shown that exercise acts on molecular pathways of bone remodeling involving all cellular types of bone tissue. In relation to clinical trials adopted in patients with osteoporosis, it is evident that a multi-component training, including aerobic activity and other types of training (resistance and/or strength exercises), is the best kind of exercise in improving bone mass and bone metabolism in older adults and especially osteopoenic and osteoporotic women. With regard to whole-body-vibration training, it seems to be a valid alternative to current methods due to its greater adaptability to patients. In conclusion, physical activity, whatever the adopted training, always has beneficial effects on patients suffering from osteoporosis, and not only on bone homeostasis but on the whole skeletal muscle system.