Muscle strength as a predictor of bone mineral density in young women

It is widely accepted that physical activity is beneficial to bone. However, the specific relationships of muscle strength to bone mineral density (BMD) are poorly understood. We examined strength and BMD in 59 women aged 18‐31 years who ranged in exercise patterns from sedentary to active. Mineral density of the right proximal femur (hip) and spine (L2‐4) was evaluated by dual‐energy x‐ray absorptiometry. BMD at the midradius was measured by single‐photon absorptiometry. Dynamic strength (one repetition maximum) was measured for the following muscle groups: back, elbow flexors (biceps), leg extensors (quadriceps), and the hip flexors, extensors, adductors, and abductors. Isometric grip strength was assessed by dynamometry.