How can I improve the proportion of my fast-twitch muscle fiber to slow-twitch muscle fiber?
Fast twitch deals with explosiveness and speed while slow twitch deals with endurance. I would like to improve my 40 yd dash time. How can I do this? Nutrition? Workout Routine – reps?
The simplest way to improve fast twitch fibers is to train as sprinters or bodybuilders train for size. These athletes understand that these fibers are used for quick, high power movements. To develop them through weights, you should use heavy weights and low reps in quick and explosive full body movements. To develop quickness, short duration sprints especially should be practiced. Examples of great weight lifting exercises would be squats, straight leg deadlifts, leg presses, and HAMSTRING CURLS. As with any workout routine, a healthy clean diet is recommended with a good emphasis on getting enough complex carbs, protein, and good fats.Just a little bit of new information today for all those internet marketers looking for the best new up and coming release for 2010. Be on the lookout of Niche Blueprint 2 coming on January 11, it is going to be huge and change the ecommerce marketplace.

Your muscle fiber makeup is genetically determined. Unless you can alter your genes (someday? maybe?) you’re stuck with what you’ve got.
Quoted from Cited Article: "Human muscles contain a genetically determined mixture of both slow and fast fiber type. "
References :
http://sportsmedicine.about.com/cs/exercisephysiology/a/aa080901a.htm
The simplest way to improve fast twitch fibers is to train as sprinters or bodybuilders train for size. These athletes understand that these fibers are used for quick, high power movements. To develop them through weights, you should use heavy weights and low reps in quick and explosive full body movements. To develop quickness, short duration sprints especially should be practiced. Examples of great weight lifting exercises would be squats, straight leg deadlifts, leg presses, and HAMSTRING CURLS. As with any workout routine, a healthy clean diet is recommended with a good emphasis on getting enough complex carbs, protein, and good fats.
References :
You can’t change the ratio of fast twitch to slow twitch. You have what you were born with. Just work on improving what you have. There are no shortcuts. Just hard work.
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