How to Improve Fast Twitch Fibers

Yoga poses require slow-twitch muscle fiber recruitment.

Muscles are composed of three main types of skeletal muscle fibers: slow-twitch, intermediate and fast-twitch. Slow-twitch fibers are used for endurance activities and are slow to fatigue. Large muscles in the back are predominantly slow-twitch. These muscles need endurance to hold a person upright. Fast-twitch fibers contract rapidly and provide short bursts of intense power for activities like sprinting. They can be found in high quantity in hand and eye muscles that move very quickly. Intermediate fibers fall between these two categories. The amount of each type of fiber in the makeup of your muscles is genetically based, however plyometric and sprinting activities can be performed to target fast-twitch fibers during training.

Things You'll Need

• 8- or 10-pound medicine ball
• 6- to 12-inch box
• 1- or 2-pound weighted ball
• trampoline

Instructions

1. Develop a plyometric training program to train your fast-twitch muscle fibers. Plyometric exercises use a stretch-shortening cycle. The muscle is first stretched, or lengthened, then quickly contracted, or shortened. Use a medicine ball to perform plyometric exercises with your arms. Lie on your back and hold the ball at your chest with your arms bent to stretch your triceps muscles. Throw the ball up toward the ceiling, straightening your arms by contracting your triceps muscles. Catch the ball as it returns, bring it to your chest and repeat 10 times.

2. Perform jumping exercises to improve fast-twitch muscle fibers in your legs. Place a 6- to 12-inch box in front of you. Squat and jump up onto the box, landing on both feet. Jump off the box and repeat 10 times. Place a small cone on the floor and jump over it with both feet together. Turn around and repeat 10 times. Progress to lateral movements, jumping sideways over the cone, and repeat 10 times.

3. Add more exercises as you build your training program. Try single leg hops, jumping in place, jumping forward and down from various heights. Perform one-hand and two-hand throwing activities with another person or against a trampoline. Jump up and touch the wall as high as you can. Increase the difficulty of your workout by performing several plyometric exercises in a circuit. Add several 10- to 30-second sprints to your circuit.

References

• Abraham Baldwin Agricultural College; PHED 1123; Weight Training Study Guide
• University of North Carolina Asheville; Biology 108; Muscle Fibers; Bryan Collins
• AthleticQuickness.com: Isometrics Training and Fast Twitch Muscle Fibers
• "Anatomy and Physiology"; Chapter 10: Muscle Tissue; Martini
• National Strength and Conditioning Association's Performance Journal; Plyometrics; 2007