Thanks for this. It stimulated a few thoughts.
Many of the "older" distance athletes in their late 30's or even early 40's are excellent at *strategy* and maximizing their own physiologic strengths. They do not make the mistake of blowing out energy to establish a lead when a comfortable top 10 position is in the offing.
Having said that distance events are not the same thing as a sprint-centric sport like hockey, where the players often skirt the wall of maximum aerobic capacity, dive deep into anaerobic respiration, expending energy in their skeletal muscle to the point of exhaustion and taking themselves beyond aerobic capacity - followed by a short recovery. The average hockey player requires extraordinarily good vascular function, particularly of the great arteries - to allow storage of potential energy into the vascular wall, expended during brief cardiac relaxation phase, which contributes to high vascular efficiency. Older individuals, on average, lose this ability for energy storage as the large arteries become less and less able to muster capacitance - this is due to changes in fibrillar collagen and elastin content in the wall of the great arteries. The vascular system becomes less efficient, and so the aerobic capacity of the athlete will gradually fall over time.
Tom Brady will rarely need maximum aerobic capacity, and so this is not his limitation per se, for him its the maintenance of insanely high motor skill/hand-eye coordination. The loss of vascular function I mentioned above will influence athletes like Blake Wheeler and other hockey players who rely heavily on maximum output and who go there every game. He knows what to do, but his body is simply not capable of those extraordinary feats of cardiac output and quick recovery any more.
