The Limits of Concurrent Training

A lot of people out there think that you can't undergo significant fiber type changes in the muscles that you have. That's a patently false for anyone who's gone out and done tests where they're attached like a respurometer or whatever. You'll never turn Chris Froome into Chris Hoy with training, but at the same time, you can definitely get a significant shift in fiber type with training. One study found that four days a week at 80% of your VO2 max is enough to fully inhibit the mTOR pathway and stop strength gains from happening.