How can one strengthen white (fast-twitch) muscle fibers?

Question

For running and swimming? How can one then strengthen red (slow twitch) muscle fibers? How can one utilize the different fibers in a race or activity?

Answer 1

I've observed and experimented on myself.  Humans are pretty unique among animals because we can do either, high power, or endurance.

The quick answer is for fast twitch, burst of power/speed you need to adjust your training to high power output, short duration sets with rest in between.  Example for weight lifting is high weight, low number of reps.  For running would be sprints with rest in between.

For endurance you need to go to the other extreme.  Weights use low weight, high number of reps with very little rest between sets.  For running long distance and low speed, not sprints.

I saw a special on discovery a few years ago where they illustrated the difference in training techniques and results as well as compared various animals.  A Russian olympic weight lifter was compared to a marathon runner.   Obivious difference in power output.  The weight lifter could barely run a lap, but his vertical leap, despite being about 3 times the weight of the runner was about 3 times as high as the runner.

Dogs are naturally marathon runners and can run for hours.  Chickens, Quail and similar birds are able to fly for short distances and have white breast meat because it has few blood vessels, they just need a short burst of power, whereas, geese and doves had dark breast meat due to the large number of blood vessels and they were capable of flying long distances.  Humans can train themselves to do either.