Mark Sisson notes that Training is no guarantee of health:
The problem with many, if not most, age group endurance athletes is that the low-level training gets out of hand. They overtrain in their exuberance to excel at racing, and they over consume carbohydrates in an effort to stay fueled. The result is that over the years, their muscle mass, immune function, and testosterone decrease, while their cortisol, insulin and oxidative output increase (unless you work so hard that you actually exhaust the adrenals, introducing an even more disconcerting scenario). Any anti-aging doc will tell you that if you do this long enough, you will hasten, rather than retard, the aging process. Studies have shown an increase in mortality when weekly caloric expenditure exceeds 4,000.That’s why I stopped racing and training ten years ago and why I prefer hiking, sprinting and weight-training today. But what’s a competitive type-A to do if s/he wants to kick age-group butt in Kona and NOT fade away prematurely?
Given carte blanche to take advantage of all that medicine has to offer, I would aggressively consume antioxidants during my training (10-20,000 ORAC units per day), I would increase the amount of healthy fats (omega 3-rich) in my diet to 50% of total calories and I would only consume quality complex carbohydrates during my training. In fact, I would calculate my carbohydrate requirements on a daily basis and not exceed them. I would use simple sugars (e.g., gels) during long rides and races only to the extent they are necessary. That means I would do most of my training without them, saving them for races. I would work closely with a trained anti-aging doctor to monitor my fasting glucose, fasting insulin, free and bound testosterone, liver enzymes, cortisol, DHEA, hematocrit, ferritin and other parameters.
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