One of the biggest concerns for runners is muscle loss. Strength training helps prevent muscle loss - even for long-distance runners. It also brings out the best in your core running muscles. If you’re concerned about your calf muscles, as many runners are, using weights to target this area is highly effective. Expect to build new muscle mass in places that are missed from just running. Weighted and non-weighted exercises benefit all areas of the calves, as well as the torso, the shoulders, glutes, and back muscles.