Further to the above and from a nutritional point of view, the master athlete's macronutrient are different from that of a younger athlete. For example being at 50 today, would mean my hormone levels are not what they once were, and since insulin's primary function is as growth hormone, after the age of (say) 25 or so, insulin takes a back seat to protein as the main building blocks, leading with the anabolic trigger amino acid Leucine.
So now a balance shifting more towards the consumption of fats (and more protein), and less of carbohydrates to suite the older athlete's requirement ought to be taken into account when designing a personalised diet plan.
Again, the above was just few pointers minus the intricate details.