Thursday 31 May 2012

Muscles in training

I like this graph. It says a lot about why 'real' sport and sport science don't quite agree. I don't have access to the original paper (Darn McGill U access isn't good enough...). I found the image from this presentation outline: Neural mechanisms are the most important determinants of strength adaptations, which as a thesis statement I wholly agree with. I like the little off-shoot of steroids, clearly implying they work for big muscles. If big muscles are not an option though, going that way is a complete waste.
 
Original paper: Moritani T and deVries HA (1979) Neural factors versus hypertrophy in the time course of muscle strength gain. American Journal of Physical Medicine 58(3):115-130

Here are three ways to think about muscles. Runners are, of course, in the 'Neural' category. Like I said, skinny runners don't increase muscle mass so much as muscle recruitment.

Runners have skinny legs, but not always the same kind of skinny. Bekele on far right has bigger quads than the Kenyan in centre. Far left is Bekele's younger brother, also fast.
 
What's interesting is that distance runners don't want to recruit ALL of their muscles in one go. This would be bad. A 'perfect' distance run would use a selection of muscles per set of strides, as chosen by your brain. Muscle recruitment is something you only have indirect control over, based on training. If you spend most of your time running it is unlikely you'll induce hypertrophy (muscle enlargement). But extreme mileage may induce some muscle enlargement to prevent injury. It all depends on the training.

Triathletes are more muscular even though they work longer than runners. It makes sense if you think about it
Does that mean running high mileage is not a good idea? I doubt it, since by 'extreme' high mileage I mean racing 100 mile runs, maybe going like 30 miles a day or more in training and 4-hour long runs. Training even 20 miles a day (split into two sessions) seems to be solidly in the 'neural' zone of training; your brain decides you'd be better off with a slim body and slender muscles.