Are certain activities more beneficial in building bones? Does cycling as opposed to running have an effect on the density of our bones? Studies are showing that high impact sports as opposed to low impact sports have a much more beneficial effect on building bone. Activities that force the bones to bend or deform slightly encourage the body to increase the number of bone cells and prepare bones for the impacts that happen normally in life. Do swimmers and cyclists put less force on their bones than runners? At the Norwegian School of Sports Sciences studies were done looking closely at the skeletons of world class cyclists and runners. All were in their 20’s, lean, both sexes, fit and had adequate calcium intake. Even though the cyclists trained more hours than the runners, their bone mineral density was much lower. If you engage in low impact sports such as swimming and cycling, although you may have considerable aerobic capacity, it may be beneficial to make time to include a strenuous weight training session to help build stronger bones.