Strength training has long been an integral component of training programs designed to improve movement speed. It is an obvious approach since the greater the amount of force a muscle can produce, the faster the arm/leg will accelerate, thereby producing high top speeds. The end result should be faster pitches, longer drives, and harder serves.

Unfortunately, many strength programs for increasing movement speed have had mixed results over the years. Sometimes they work like a charm, other times there is no noticeable change in the athlete's performance. The mixed results are intriguing because it seems impossible that giving the muscular system the capacity to produce more force would not result in faster movement. Recent research may provide some insight to explain the inconsistent results.

In any fast movement, there are two essential parts of the action, 1) accelerating the limb to top speed, and 2) stopping it. Traditionally, strength training for speed has focused on improving the strength of the muscles responsible for accelerating the movement. In other words, the emphasis is on training the agonist muscles. These muscles are targeted with the assumption that if they are stronger, they can do things like accelerate the arm faster, which will result in a faster pitch. The antagonist muscles, the ones responsible for stopping the limb at the end of the movement, are not trained as much. This lack of attention to the antagonists could explain why athletes who should be able to go faster do not.

Studies of fast movements and strength training at the elbow have found that when the antagonist muscle (the triceps) was trained, movement was faster. Yet, when the agonist (the biceps) was trained, no significant change occurred in the movement speed. The reasoning is simple. At the elbow, the biceps is stronger than the triceps in most athletes. When the agonist is stronger than the antagonist, the neuromuscular system limits movement to speeds that the triceps can safely brake - even if the biceps could make the arm move faster.

It is the same safety precaution you would take if driving a car. Imagine that you had a car that could travel at 150 mph but brakes that could stop you only at 100 mph or slower. Would you drive 150 mph? No, and for the same reasons, the body will not allow the arm to move faster than it can be stopped. So, the traditional approach to strengthening a pitcher's throwing motion may not be enough to ensure that he will throw faster. Interestingly, faster pitches may be more dependent on getting stronger brakes than accelerators.

One additional finding of the research is important to note. When the stronger muscle was the braking muscle (biceps), strengthening the triceps did indeed result in faster movements. This just emphasizes the point that the speed athletes will move is based on the strength of the weakest muscle, which is often the antagonist.

The first step to applying this to your training programs is to do a careful analysis of the movement you are trying to make faster. Determine which muscles are accelerating the movement and which muscles are decelerating the movement. In many sport movements, the antagonists are the weaker muscles.

Then, design a strength training program that focuses on the weaker of the two muscles. Optimally, structure your workouts so that the weaker muscle gets more reps than the stronger muscle. This way your weaker muscle will make greater gains in strength while still improving the stronger muscle. This training approach will benefit both the acceleration and deceleration capability of the athlete.

Other research has provided additional tips on how to specifically train the antagonists. These exercise designs should be used in conjunction with isolated strength work for the muscles. Consider doing some of the exercises at faster speeds so that the muscle gets used to performing at faster speeds. To do this safely, you may need special equipment such as pulleys that can protect athletes from injury if the exercise is performed incorrectly. Look for systems that minimize the amount of "jump" in the weight stack when you move quickly.

Another consideration is the type of contraction and the angle at which the muscle has to work. This is especially important for training the braking muscles that are always using an eccentric contraction. Again, use a pulley system that can be adjusted to any height to allow you to place the angle of pull in the right place to mimic the way the muscle has to perform during the real movement. Emphasize the eccentric phase of the movement and work at faster speeds for maximum results.

Traditionally, training athletes for faster movement has focused on strengthening the acceleration muscles. Research has shown that this is not the only important component. Training the muscles to be better at stopping fast movements is equally critical. To make an athlete move faster, training must emphasize the antagonist.

Overall, analyzing your current training programs may reveal that you have been successfully training the right muscles. Hopefully, when you have an athlete that is not responding, keeping this information in mind may help you maximize their potential.

Christine Cunningham is the owner of performENHANCE sports performance training in Chicago and a member of the Life Fitness Academy. She currently is getting her PhD in exercise neuroscience at the University of Illinois at Chicago and can be reached at cunni5@uic.edu.

Recommended Reading:
Jaric, S. Changes in movement symmetry associated with strengthening and fatigue of agonist and antagoinist muscles. J. Mot. Behav. 32: 9-15, 2000.

Jaric, S., Ropret, R., Kukolj, M. and Ilic, D.B. Role of agonist and antagonist muscle strength in performance of rapid movements. Eur. J. Appl. Physiol. 71: 464-468, 1995.

Morrissey, M.C., Harman, E.A., and Johnson, M.J. Resistance training modes: Specificity and effectiveness. Med Sci Sports Exerc. 27:648-660,1995.