As this occurs, the aging individual, sooner or later, notices that they can no longer eat all that they used to without gaining weight. Overall fitness requires more than just cardiovascular fitness. A balance of endurance, strength, and flexibility must be achieved. Running gives the quickest results in the area of cardiovascular fitness, but besides strengthening a few specific muscles and rapidly burning a lot of calories does not greatly contribute to the other criterion of fitness. Strength training or Resistance training may help contribute to the other areas of fitness.
Resistance training can also improve performance for a variety of sports.
While its impact may, in some cases, be limited for the long distance runner, it certainly can help the performance of a triathlete, and many other athletes who participate in a variety of sports. There are benefits to participating in strength training for the long distance runner. Those sore shoulders and tired arms at the end of long run, and those achy backs might become less troublesome. The long distance runner may find a bit more power for the sprint to the finish line and may find that improved arm strength allows for an easier crank up a hill and better balance on trails. The older runner will find that he has lost lean muscle mass from the aging process.