I am asked this question a lot by parents and even coaches. What I know and have experienced with Overload & Underload Training–(that’s the real name of this concept) Now before we get started I want you to know that that I am not advocating overload-underload training OVER conventional training methods. Rather I feel strongly if none correctly that combining overload-underload training with intelligently planned training progressions (strength, flexibility/mobility, power, recovery) players can get extraordinary results)

Last year I was part of a coaching staff that used overload-underload training with their players. What I experienced is somewhat mixed–I saw players (mostly pitchers) increase their throwing velocity, arm strength increased, added flexibility/mobility to arm and joints of the arm as well in adding stability to the scapular of the shoulder. Ok, so that’s all good and great, yet In my professional opinion I was uncomfortable with the stress it can cause if the program length is too long. Recently, the renowned and respected S&C Coach Eric Cressey posted his thoughts on Weighted Balls and J-Bands not to long ago–check it out — http://ericcressey.com/strength-and-conditioning-programs-methods-vs-applications.


The concept of overload-underload training is a simple one that has been used since the 1970’s by Olympic athletes to get dramatic performance increases in relatively short amounts of time. Unfortunately, the concept still remained a mystery to the majority of the general public until recent years. Overload Underload training is a training concept that uses resistances slightly above and below what one would encounter in his/her respective sport. So, for baseball that would mean swinging a baseball bat or throwing a baseball that is roughly 20% over and 20% under the normal weight one would usually encounter. This concept was studied extensively by the Soviet Union and other Eastern bloc countries back in the 1970’s. These countries took great pride in their athletic accomplishments and poured millions of dollars in research into more efficient ways to build better athletes. After experimenting with their Olympic throwers (shot put, javelin, hammer, and discus) they discovered that by increasing or decreasing the resistance of the projectiles that were thrown in practice, they could produce significant gains in throwing distance (and velocity) with objects of regulation weight. This was a huge find since strength and power gains from traditional weight training often doesn’t transfer well to more complex sporting motions such as throwing and hitting.


Over the years there have been numerous studies done to determine the effects of overload underload training on performance and safety. The majority of overload underload training research has been done with throwing a baseball. The research has all come back with stellar results. Not only did the players participating in the program make significant gains in velocity, but they also stayed healthy for the following season, a difficult accomplishment considering the stress that throwing a baseball puts on the muscles, tendons, and ligaments of the arm. The two most notable studies on the use of overload underload training for bat speed improvement and throwing velocity improvement comes from Coop DeRenne, one of the world’s premier research leaders in terms of overload underload training for baseball. DeRenne and colleagues came to the same conclusion as many of the world’s top sports scientists which is: overload underload training is simply one of the simplest and most effective ways to make significant performance improvements in a short amount of time.

Coop DeRenne, Barton P. Buxton, Ronald K. Hetzler and Kwok W. Ho. 1995: Effects of Weighted Bat Implement Training on Bat Swing Velocity. The Journal of Strength and Conditioning Research: Vol. 9, No. 4, pp. 247�250.
Coop DeRenne, Barton P. Buxton, Ronald K. Hetzler and Kwok W. Ho. 1994: Effects of Under- and Overweighted Implement Training on Pitching Velocity. The Journal of Strength and Conditioning Research: Vol. 8, No. 4, pp. 247�250.