How exercise changes our DNA?
well.blogs.nytimes.com
well.blogs.nytimes.com
I've mentioned here before, but John J. Ratey recently wrote the excellent Spark: The Revolutionary New Science of Exercise and the Brain[1], where he explains in colorful details what happens in (and to) the brain when you exercise.
[1] http://www.amazon.com/Spark-Revolutionary-Science-Exercise-B...
1. https://en.wikipedia.org/wiki/Transgenerational_epigenetics
In fact, my uneducated first guess would be that the different methylation patterns are related to the actual buildup in strength, which itself would require some way of coding for the expression of certain genes differently in one set of muscle cells than in another.
http://www.sciencedirect.com/science/article/pii/S0092867414...
http://www.telegraph.co.uk/news/science/science-news/1048647...