Q: Hi Mike, I am a 73 year old with a weights Programme which I have been following for about 3 months. Progress with muscle gain is very slow but I do understand why at my age. However, in my youth, I was a runner and had a marathon time of just under 3 and a quarter hours BUT I couldnt do a 10K in less than 40 minutes. I am told this is because I have a preponderance of slow twitch fibres. OK....this is my question.....if I have lots of slow twitch fibres and given that I cannot at my age increase (by number) my fast twitch, would I be making more muscle gains if I switched to a lower weight high rep. Programme? Thanks in advance for your advice......

A: There's no evidence that a lower weight + higher reps program would be more suitable for 'slow-twitch' dominant individuals. The simplest reason is that slow-twitch doesn't have nearly the muscle size increase potential of fast-twitch fibers, so even if you don't have much fast-twitch fibers, they still ought to be your focus.

I also would not be quick to jump to the conclusion that you are necessarily slow-twitch dominant simply because of those times in the marathon and 10K since both events rely almost exclusively on slow-twitch. But again, even if you are slow-twitch dominant I would still recommend keeping up the weights for higher intensity targeted at whatever fast-twitch you may have. Unfortunately, as you noted, it simply gets difficult to build and maintain muscle with age.