A functional cooperation exists between bones and skeletal muscles. Bones work together with muscles as a simple mechanical lever system to produce body movement. One of the important functions of bones is to exert resistance against gravity in order to carry the body. In order to carry out their mechanical functions, bones need to have considerable resistance to deformation under load. It is well-known that muscle activity (i.e., exercises) improves the resistance of bone to mechanical loading, and that it is also important for treating and preventing osteoporosis. Resistance and impact training have been shown to induce bone formation and/or prevent bone resorption. Skeletal muscles have positive effects on bone structure and function. Can bones have an effect on muscle activity? There is only one study about the effect of bones on muscles. In this study, it was shown that bones may affect muscle strength gain in healthy young adult males.