Section: EXERCISE
WORK IT OUT
Develop fast-twitch muscle fibers for more physical gains.
Most fitness training programs miss out on one of the most essential elements in training the body–speed. Training programs often focus solely on working the slow-twitch muscle fibers. Virtually all aerobic, distance endurance training, as well as most weight training, “work” the slow-twitch fibers. Muscles, however, are made up of half fast-twitch and half slow-twitch fibers. Elizabeth Quinn, MS, an exercise physiologist points out:
Fast-twitch fibers [types IIA and IIB] produce force al a higher rate (they fire more rapidly). They use anaerobic metabolism for short bursts of speed and strength and they have a greater force output than slow-twitch fibers. So a lot of fast-twitch fibers can be an asset to a sprinter when there is a limited amount of time to generate maximal force. The stow-twitch fibers, on the other hand, fire less rapidly, but can go for a long lime before they fatigue because they use aerobic metabolism.( n1, n2)
Both muscle fiber types are important, but since common training techniques such as jogging, stair-stepping and standard weightlifting training use slow-twitch fibers, the slow–action fiber development occurs more readily. This affects the appearance of the muscles too, since slow-twitch fibers are smaller than fast-twitch fibers. Kristy Crowley, MS, CSCS, USAW, Fordham University Assistant Strength and Conditioning Coach, saw this in basketball conditioning.
Aerobic conditioning, such as the one- or two-mile run test, recruits the slow-twitch muscle fibers. Training the slow-twitch muscle fibers will hinder an athlete’s performance on the basketball court because this endurance-type of training reduces the overall muscle mass of fast-twitch type II fibers. Although hypertrophy is enhanced in type I muscle fibers, the resulting cross-sectional diameter is not as great as when type II fibers are recruited during anaerobic training.( n3)
Each type of muscle fiber responds specifically to the type of work by increasing in size. Light to moderate intensity exercise utilizes type I fibers whereas moderate to vigorous intensity exercise utilizes type IIA fibers and heavy intensity exercise recruits type IIB fibers.
Introduce Your Clients to Fast-twitch Training
For a real boost to the physique, training the fast-twitch muscle fibers offers the advantage of some noticeable new gains in muscularity, and also helps the body become leaner. The more muscle fiber the body has, the more fat it burns both during the workout and after. Muscle burns calories at a much higher rate than fat does, and introducing fast-twitch muscle fiber training will build up these crucial fibers in the body.
Fast-twitch muscle fiber is worked via explosive action, or plyometrics, where the stretch reflex is used to increase muscle fiber recruitment. A few great tools for employing explosive training include sprinting, jumping and explosive weightlifting. These are also known as rebound-, reactive-, jumping-, or power-training. The exercise eccentrically loads the muscles and requires them to contract explosively on the rebound. It requires increased levels of coordination and has the potential for injury.( n4)
Running and Lifting
Running is both a slow-twitch and fast-twitch training tool, depending on the speed and acceleration and the amount of sustained time at a certain speed. Jogging is primarily a slow-twitch muscle fiber exercise; sprinting is a fast-twitch muscle fiber exercise, as is jumping (in squat jumps, horizontal jumps and tuck jumps).
Explosive lifting involves simply moving the weights at fast speeds, especially in medicine ball passes and abdominal curl ups with ball passes. Combination movements such as the “clean and jerk,” or “clean and push press” are examples of the speed style of lifting. Speed can also be used in the traditional movements such as the bench press, cable rowing or triceps pushdown. The pace of the movement is the determining factor, as long as the weight being moved is significant enough to challenge the body.
By putting together a program that includes some sprinting and explosive lifting, you can help your clients target their fast-twitch muscles. Introduce your clients to the impressive benefits of speed and get your clients growing again.
Examples of Exercises
SPRINTING: Can be performed on a track (or anywhere else that is smooth and straight), a bike (recumbent or upright) or treadmill.
The best way to start with sprints is at a 50 percent effort after warming up sufficiently (especially the hamstrings and calves). Move up in intensity to sprints at 65 percent effort, 75 percent effort and then 85 percent effort in the first few workouts. Gradually work up to eight sprints per workout. If you are on a track, aim for 50- to 100-meter sprints. If you are using a recumbent bike or treadmill, perform 20- to 30-second sprints and gradually increase to more intense sprints.
13n1.jpgSPRINTING
13n2.jpgEXPLOSIVE LIFTING
EXPLOSIVE LIFTING: Introduce with the clean and jerk.
- The clean and jerk works virtually all the major muscle groups in the body and really gets the metabolism going. Start off with lighter weights to become accustomed to the action of moving the iron fast. Form is especially important when moving the weight at high velocity, so make sure each phase is perfected prior to pumping up the heavier weights. Start the first phase in a squat position with the barbell on the floor; flip the barbell into the racked position across the deltoids and clavicles while still squatting. In the second phase, rise up using the split technique, while pushing the weight overhead with straight arms. Then, in the third phase, the feet come together as the weight is held overhead. The weight is then returned to the floor. This move can also be performed using dumbbells with good results.
- The snatch is another excellent movement for getting most of the major muscles involved; but it is more technical in nature and may take longer to learn. Start in a squat and then pull the barbell to the chest and flip it overhead with the arms extended in one smooth move as you stand up from the squat. Use a 5 to 8 repetition range for these movements for 2 to 3 intense sets.
REFERENCES
(n1.) QUINN, E. “FAST AND SLOW TWITCH MUSCLE FIBERS.” WWW.SPORTSMEDICINE.ABOUT.COM/CS/EXERCISEPHYSIOLOGY/A/AA080901A.HTM (ACCESSED DEC 10, 2007).
(n2.) TAYLOR, J. “A TACTICAL METABOLIC TRAINING MODEL FOR COLLEGIATE BASKETBALL.” STRENGTH AND CONDITIONING JOURNAL 26, NO. 5 (2004): 22-29.
(n3.) CROWLEY, K. “ENERGY SPECIFIC TRAINING FOR THE GAME OF BASKETBALL.” WWW.THESPORTJOURNAL.ORG/2005JOURNAL/VOL8NO2/SCJ_02_KRISTY-CROWLEY.ASP (ACCESSED DEC 10, 2007).
(n4.) YOKE, M. PERSONAL FITNESS TRAINING: THEORY & PRACTICE. SHERMAN OAKS, CALIF.: AFAA, 2006. CAMPBELL, P. READY, SET, GO! SYNERGY FITNESS FOR TIME-CRUNCHED ADULTS. JACKSON, TENN.: PRISTINE PUBLISHERS INC., FEB 2002.
By Dwayne Hines II
Dwayne Hines II, is certified with the National Strength and Conditioning Association as a personal trainer. He has written a variety of training books, including Six Pack Abs in 60 Days (Muscle Magazine International, 1998), which is available at amazon.com as well as Barnes and Noble. In addition to his clients, he also enjoys teaching his two young boys the joys of fitness and good nutrition.