Exercise and bone growth
Exercises that stimulate new bone formation are those that involve many muscle groups and multi-joints in one exercise, direct the force through the spine and hip, and allow greater absolute loads in training. Single-joint (or isolated or assistance) exercises should be limited. For example, performing the leg extension instead of the barbell back squat eliminates the compressive forces on the individual’s back and the muscular contractions of the synergistic muscle groups acting on the vertebral column for stabilisation during the exercise. The only force experienced by the lower limb during the knee extension exercise is at the point of muscle attachment of the quadriceps on the tibia. Therefore, structural exercises such as squats, deadlifts, cleans, etc (for the axial skeleton and hip) and bench press and overhead presses (for the upper limbs) will increase muscle and bone strength (NSCA).
The principle of progressive overload should be applied, with a progressive increase of the load (and therefore stress) as the tissues become accustomed to the stimulus. In addition, the exercises should be varied, changing the distribution of the direction of force to continually present a unique stimulus for new bone formation.