Also read the Training for Fiber Type - article by Bryan Haycock You can't isolate fiber types in training for hypertrophy (or strength for that matter). All the notions of training for different fiber types is a misunderstanding of how muscle fibers are activated, or recruited. Slow twitch fibers are activated first, followed by fast twitch fibers in any muscle contraction. This is a function of small "motor units" (slow twitch fibers) being activated first for small precise movements/contractions of low force, followed by large motor units (fast twitch fibers) for large and powerful movements of relatively high force. All fibers are generally activated in a muscle at 85% of 1RM, but this may actually be as low as 50% of 1RM for some muscle groups. So the argument about training specifically for different fiber types is wrong from the very foundation. It is simple misinformation based on a lack of understanding about motor units and their recruitment patterns. What those programs you have come across aimed at training for specific fiber types are actually doing is training for different metabolic pathways (e.g. ATP>Glycolytic>beta-oxidative). In order to make a muscle grow you must apply high forces. This requires high loads. This requires that the body activate ALL fiber-types/motor-units during a contraction that is against sufficient load to induce microtrauma and hypertrophy. ANY biomechanics or kinesiology text book will explain in great detail the correct properties, functions, and recruitment patterns of different fiber types and motor units. Anyone with this basic knowledge of functional anatomy could not possibly claim that isolation of fiber types is possible with loads required for muscle hypertrophy. In essence, it would be like saying that you could rev a motor at 1,000 RPM without reving it at 500 RPM. If you have a high makeup of slow twitch fibers, all that changes is the relative %ages of 1RM you can do a certain amount of reps with. Just lay out your HST program, get your diet in order, and you will grow....day by day. Just like everybody else.