Strength Training Project for Baseball/Softball

 

      Strength-training programs have long been recognized as a vital component of successful athletes and teams.  The emphasis on strength training for improved athletic performance began to take hold when Boyd Epley introduced a weight- lifting program to the University of Nebraska’s football team in 1969 (Musgrave, 2001).  For the next twenty years, the connection between strength training and the improvement in athletic performance focused primarily on football players.  Since the late 1980s, there has been a tremendous increase in the use of strength training to improve the performances of athletes in other sports as well.  Athletes in a variety of venues are using weight training to get bigger, stronger, and faster.  It is only within the past ten years, however, that strength training’s role in improving athletic performances of individuals participating in the sport of baseball has been recognized and expanded.  During this time, there has been a greater emphasis on offensive production and scoring in baseball.  This emphasis has focused primarily on an increase in the number of home runs being hit.  The strength and power needed to improve a player’s offensive output and home-run-hitting ability has led to an increase in the use of year-round, strength-training programs. 

      Despite the recent surge in the use of strength-training programs as a tool for improving performances of baseball players, the resources for implementing these programs and the data on the actual effects of these programs are limited.  In addition to the limited resources, many myths exist concerning the effects of strength training on a baseball player’s body and his performance on the field.  For example, many people have the misconception that strength training limits the overall flexibility of a player, which can hinder a player’s throwing and hitting ability.  This project will attempt to dispel such myths by showing how a strength-training program can positively influence a baseball player’s levels of strength, endurance, flexibility, and overall athletic performance.

 

Project Outcomes

 

      The primary objective of my project was to develop a resource guide and video that would enable coaches to create and implement their own strength-training programs.  This project was also designed to be an informative resource for the data that exists on the effects of strength programs upon the performances of baseball players.  Specific outcomes desired for this project involved the means of improving the athletic performance components of baseball players.  These performance components include throwing velocity, batting average, hitting power, and running speed.  As a coach responsible for the strength-training program of my team, it is my goal to develop the players to their highest potential of athletic performance.  I believe that one of the ways that this can be accomplished is through an appropriate and effective strength-training program. 

      The baseline measurement for determining the levels of each of the athletic performance components is ultimately based on the performance and production of the athlete on the field, and the performance of the athlete’s team in regards to wins and losses.  While there are many factors that can lead to a higher level of performance by an individual or a team, one such factor is an improvement in the physical condition of the athlete through the use of strength training.  It is a difficult task, however, to determine whether physical condition was the most important factor in improving the level of performance outcomes, or if another factor was indeed more critical.

      To determine the physical effects and outcomes of strength training on an athlete, an evaluation tool has been designed to help identify the athlete’s level of improvement.  The evaluation tool involves the testing of an athlete’s one-repetition maximum in particular core lifts at various times throughout the year.  The one-repetition maximum is an expression of the maximum amount of weight an athlete can lift in a particular exercise.  The one-repetition maximum is commonly calculated by inserting the results of an athlete’s multiple-repetition maximum into a formula.  The one-repetition maximum is vital to the success of a strength-training program since it is the factor that determines the intensity to be used in core lifts.  The baseline data for the one-repetition maximums is recorded at the beginning of the school year, following the off-season lifting program that the athletes participated in over the summer.  The athletes are tested again at the end of the fall program in November, again at the end of the winter program in January, and once more at the end of the baseball season in May, which precedes the summer program.  The athletes and coaches can use the data that is recorded during these evaluations to determine the level resistance to be used in the core lifts, referred to as the level of intensity.  The level of intensity is a percentage of the one-repetition maximum in the core lifts and varies throughout the course of the strength-training program.  This data can also be used to make comparisons between the various training programs utilized by the coaches throughout the year. 

      I reviewed the existing research in order to determine the effects of a strength-training program upon the player’s athletic performance on the field and the subsequent performance of the team.  There was a limited amount of information available on these topics, especially pertaining to the effects of strength training on team performance.

 

Review of Literature

 

      It is evident with the improvements in athletic performances and the continual breaking of long-standing records, that strength-training programs have had a tremendous impact on the training regimens of athletes in all sports.  There is a great deal of research that confirms that strength-training programs can lead to an improved level of performance. Historically, baseball has lagged behind other sports in the implementation of strength-training programs.  More recently, however, professional baseball players have stressed the importance of these programs in the development and improvement of their play.  One need to look no further than the record-breaking year of 1998, when Mark McGuire and Sammy Sosa both shattered the season record for home runs, for the evidence of the role that strength training has in a baseball player’s performance.  Both players acknowledged that strength training played a key role in the development of their powerful, record-setting swings (Shepard, 1998).  With the increased exposure of the role of strength training in baseball performance, many books have been published which promote generic training programs that promise to improve a baseball player’s level of performance.  However, existing literature and research have shown that in order for a training program to be successful in helping to attain improvements in baseball player’s performances, it should be tailored to the needs of each baseball program and the individual athlete, and it should also be specific in terms of improving those skills necessary to the sport of baseball.  It is these standards that determine whether or not a strength-training program is effective and appropriate for high-school and collegiate players.

      Baseball is a sport that has traditionally been unresponsive to change.  This is evident in the area of conditioning programs.  Baseball coaches typically have used conservative methods when conditioning their players, and often use the same methods year after year.  There are coaches who are willing to use training methods that may be new to them, but because of unfounded concerns or training fallacies, they may be reluctant to incorporate systematic and comprehensive training programs in fear of hindering their athletes.  For example, many baseball coaches do not recommend weight training for their players for fear that it could cause their players to become too bulky, limit their range of motion, and decrease their overall flexibility, all of which could lead to a decreased level of performance.  However, research by Murphy and Forney has shown that a proper program will not overly bulk up a player and will actually increase range of motion  (Murphy & Forney, 1997).  Another study by Potteiger, Williford, Blessing, and Smidt also showed that if players performed weight-training exercises correctly, muscular flexibility could be increased (Potteiger, Williford, Blessing, & Smidt, 1992).  Any effective strength-training program should incorporate exercises that will aid in increasing and maintaining the athlete’s level of flexibility.

 

Strength Training Background

 

      A sport-specific training program is designed to improve a player’s overall physical condition and enhance his performance of a sport-specific skill.  An appropriate program takes a multi-dimensional approach to attaining the desired results.  This type of program focuses on improving the training components of muscular strength and power, anaerobic and aerobic capacity, body composition, and flexibility.  The specific skills of running, throwing, hitting, and fielding depend upon these training components, and while some may be more important than others, improving these training components can result in a positive influence of the performance of the aforementioned skills as required in baseball (Hagerman, Starr, & Murray, 1989).

      Controversy and debate on the benefits of supplemental conditioning exercises continues to exist among those in the baseball profession.  Supplemental exercises, also referred to as auxiliary exercises, are those exercises that generally have no direct effect on baseball skill development.  It is difficult to measure the effect that supplemental exercises have on improving the level of a baseball player’s performance; but experts in other skill-oriented sports have recommended adopting supplemental, non-specific exercise programs as part of an athlete’s training regimen.  Their recommendations were based upon observed improvements in performance of athletes who have participated in successful testing and conditioning regimens (Hagerman, et al., 1989).

      Muscular strength and power are the two most important training components to consider when developing a strength-training program for baseball players.  Strength refers to the ability of a muscle or muscle group to exert force.  It is a training component vital in many of the skills necessary in baseball competition.  Power refers to the ability of the neuromuscular system to overcome a resistance in a given time period.  Maximal force is generated through rapid, explosive movements of the muscles. (Watkinson, 1997).

      The source of power for baseball hitters and pitchers is centered in the musculature of the trunk and lower body regions.  Baseball players need appropriate trunk and lower body development in order to transfer power from the muscles to the movements required in hitting and pitching (Gardner & Schwab, 1998).  Most of this force is initiated in the lower body and trunk musculature, where it then must be transferred and accelerated through the upper body to the bat or the ball (Weatherly & Schinck, 1996). 

      Rapid rotational and explosive movements of the trunk, which are initiated in the hips and legs, are common in hitting and pitching movements.  Rotational trunk movements may contribute fully half of the force in a pitching or throwing motion.  The trunk must transfer the momentum created in the lower extremities up to the throwing arm, in turn generating the high angular velocities specific to pitching (Gardner & Schwab, 1998).  According to the results of a biomechanical study, 47% of the velocity of the overhand throw can be attributed to the stride and body rotation, whereas 53% of the velocity was due to action of the arm.  Therefore, training programs for baseball players to improve throwing velocity should be designed to include arm, trunk, and lower-body exercises (DeRenne, Ho, & Murphy, 2001).

      Of course, trunk rotation is also vital in hitting the baseball.  The legs accelerate initially, followed by an acceleration of the trunk region.  The legs and trunk then decelerate, which facilitates the arms coming through in a manner analogous to a whipping type of motion as the bat passes through during the swing (Weatherly & Schinck, 1996).

      The legs are used primarily in gross movements that are mainly unilateral.  The legs have higher force requirements than the upper body because they must propel the weight of the player’s body.  The trunk movements utilized in hitting and throwing are diagonal and rotational in nature.  The trunk is responsible for receiving, producing, and transmitting force through these diagonal/rotational movements primarily through the muscles of the abdomen and the lower back.  The upper body movements are exceptionally rapid and are considered to be fine motor skills.  Throwing and hitting also require high-speed, eccentric strength for deceleration purposes (Weatherly & Schinck, 1996).

      Players can throw with greater velocity and hit with more power when the muscles of the trunk, lower body, and arm/ shoulder areas move at greater velocities.  Players can achieve greater muscular movement velocities by training their muscles to generate forces in less time (Watkinson, 1997). 

      The abdominals, obliques, lower back muscles, gluteals, hamstrings, quadriceps, and muscles of the hip region initiate power and should be trained in a high-velocity, explosive manner.  Therefore, core exercises in a strength-training program for baseball players should consist of parallel squats and power cleans, two exercises that focus on developing maximal power output in the major muscles of the upper leg and hip regions (Shepard, 1998). Training methods utilizing plyometric exercises and medicine balls are effective in the development of the abdominal and lower back muscles (Odgers, 1993).

      Muscles of the shoulder/arm region should be trained in a more conventional manner.  Exercises used to train this region should focus on internal and external shoulder rotation (Weatherly & Schinck, 1996).  Stabilizing exercises are necessary for the shoulder and rotator cuff regions and should be baseball specific in nature (Gardner & Schwab, 1998).  In addition to the training of the muscles responsible for acceleration of the arms in hitting and throwing movements, an emphasis should also be placed on the training of the muscles responsible for the deceleration of the arms in these movements, an area that is often neglected in exercise programs (Panariello, 1992).

 

Training Effects on Throwing Velocity

 

      A review of the literature revealed that a majority of the studies that evaluated performance variables tended to focus on throwing velocity as the measurable factor.  Throwing velocity refers to the velocity at which an individual can throw a baseball.  Throwing velocity is one of the more important determinants of success in baseball, especially among pitchers.  The review of the literature indicated that throwing velocity could be increased with an improvement of the biomechanics necessary in throwing movements, or by incorporating a resistance-training program that trains the muscles used in these movements (DeRenne, et al., 2001).  This portion of the review will focus on the effects of resistance- or strength-training programs on throwing velocity.

      In a study conducted by Lachowetz, Evon, and Pastiglione (1998) which measured throwing velocity, a comparison was made between two groups of baseball players during the fall portion of the preseason.  The treatment group received eight weeks of strength training while the control received no training.  Previous research on the relation between strength training and throwing velocity had focused on increasing the strength of the muscles responsible for acceleration of the arm, with minimal attention given to the muscles responsible for arm deceleration.  The training program in this study, however, addressed the issue of muscle balance by specifically targeting both the muscles responsible for acceleration and deceleration of the throwing arm.  Analysis showed a significantly higher mean for throwing velocity of the treatment group following the eight weeks of strength training (Lachowetz, Evon, & Pastiglione, 1998).

      In a 1994 study which measured throwing velocity, Newton and McEvoy made a comparison between two forms of upper-body training programs.  One group utilized plyometric training which incorporated the use of medicine balls.  In the second group, conventional weight-training methods were utilized.  A control group that did not participate in any training was also used in this study.

      The use of medicine balls as a means to improve the throwing velocity of baseball players is a type of training based on the specificity of training theory.  In this case, the specificity of training theory rationalizes that medicine ball training is more specific to the throwing action used in baseball in terms of the velocity of movement, the load being accelerated, and the execution of a coordinated full-body action.  Therefore, it would be expected that training with medicine balls would be more effective than traditional weight training.  However, upon completion of the study, the weight-training group showed a noticeable increase in throwing velocity, while the group that trained with medicine balls showed no significant increase in throwing velocity.  The group that trained with medicine balls did, however, show a significant increase in levels of strength (Newton & McEvoy, 1994).

      DeRenne, Ho, and Murphy (2001) reviewed the three broad categories of resistance-training methods by which throwing velocity could be improved.  According to DeRenne, Ho, and Murphy, resistance-training exercises are classified as general, special, or specific, depending on their biomechanical characteristics and effects on the neuromuscular system. 

      The first category, general-resistance exercises, aims to increase the overall, maximal strength of the muscles.  In theory, general-resistance exercises aim to improve the contractile capabilities of the muscle.  General-resistance exercises typically are isotonic in nature.  Traditionally, isotonic-resistance training used in throwing velocity studies among high-school and collegiate baseball players involved upper-body free-weight exercises, including those exercises that utilized dumbbells to train the shoulder region.  The majority of these studies demonstrated that a significant increase in throwing velocity could result from upper-body isotonic training (DeRenne, et al., 2001).

      The second category, special-resistance exercises, can be used to train athletes for the development of muscular power.  The purpose of training with special-resistance exercises is to convert general muscular strength to the quality of muscular power as it is relevant to throwing.  Special-resistance exercises produce the explosive muscular power output needed for the ballistic movements of throwing.      

      Studies previously done on special-resistance exercises and their effects on throwing velocity have focused on three types of training methods.  The first type is concentric/eccentric training, which concentrates on the explosive concentric/eccentric movements that target the muscles used for acceleration and deceleration of the throwing arm.  The second type is ballistic training, which combines the powerful elements of plyometric training and weight training.  The exercise protocol for ballistic training involves the lifting of relatively light loads at high speeds.  Ballistic training has been supported by numerous strength-training coaches who believe that the closer the velocity and movement pattern of the training exercise is to the actual skill required in a competitive sport, the greater the transfer of training gains to the athletic performance.  The final type of training is isokinetic training, in which the speed of movement is fixed and the resistance varies in accordance with the amount of muscular force exerted.  It appears, based on the results of research, that all three types of special-resistance training can significantly improve throwing velocity (DeRenne, et al., 2001).

      Specific-resistance exercises are designed to adhere to the concept of specificity by providing a training stimulus that is very similar to an actual motion or skill performed in competition.  Examples of specific-resistance training included exercises that incorporate weighted implements, surgical tubing, wall pulleys, and exercise rubber bands.  Studies have sought to prove whether or not specific-resistance training exercises principally recruit the high-threshold motor units used in the movements of throwing by imitating the actual motion and velocity of these movements.  Results have been inconclusive to this point on this matter.  However, studies conducted on specific-resistance exercises have all reported an increase in throwing velocity after training with these methods (DeRenne, et al., 2001).

    

Training Effects on the Reduction of Shoulder and Elbow Pain

 

      Shoulder injuries are reported to be the most common type of baseball injury, accounting for 19% of all injuries, while elbow injuries comprise 8% of the reported injuries.  Research showed that the rotator cuff complex is involved in 68% of shoulder injuries in baseball.  Most physicians, physical therapists, and coaches agree that the nature of the repetitive eccentric, contractions of the rotator cuff and the biceps during the deceleration/follow-through phase of a pitch is the primary reason for the high number of injuries to these areas (Lachowetz, Drury, Elliot, Evon, & Pastiglione, 1998).

      Several studies have investigated the concentric strength of the arm musculature in the throwing motion, but there has been little research on eccentric strength of the arm.  Concentric strength is important in the acceleration phase of the throwing motion as the upper body muscles needed in throwing movements contract in preparation of the delivery of the baseball.  However, it is the eccentric strength of these upper body muscles required during the deceleration/follow-through phase that may be most critical in preventing injury (Lachowetz, Drury, et al., 1998).

      In a study conducted by Lachowetz, Drury, Elliot, Evon, and Pastiglione, baseball players were randomly assigned to a training group and a control group.  The training group participated in eight weeks of strength training consisting of eleven exercises involving a combination of isokinetic machines, free-weight equipment, and a cable-pulley machine.  The control group received no training.  After the eight-week training period, both groups participated in a maximal-effort throwing session followed by pain measurements for the elbow and shoulder; the measurements were recorded with a 10-cm visual analog scale.  Initially, pain levels were measured in the elbow and shoulder area prior to the maximal-effort throwing session in order to establish a baseline level of pain.  Pain levels were then measured at intervals of 24 hours, 48 hours, and 72 hours following the maximal-effort throwing session.  There were no significant differences in shoulder pain at baseline, but there were significant differences in shoulder pain levels between groups at the 24-, 48-, 72-hour time intervals with regard to mean shoulder pain.  There were no significant differences in mean elbow pain levels between groups at baseline or at any of the time intervals (Lachowetz, Drury, et al., 1998).

      The data of this study suggested that strength-training programs for intercollegiate baseball players can yield the benefits associated with eccentric training.  The belief that baseball players will suffer losses in flexibility, and thus suffer decreases in performance, from regimens that employ eccentric training appears to be a myth.  In fact, research has shown that players who do not participate in strength training, particularly during the competitive season, are at a greater risk for performance decrements.  Strength-training programs, particularly those that incorporate an eccentric component, can result in an increase in strength and a reduction in post-throwing pain, allowing for a quicker recovery time between throwing bouts.  In addition to these benefits, eccentric training programs can contribute to an increase in throwing velocity (Lachowetz, Drury, et al., 1998).

 

Training Effects on Overall Athletic Conditioning and Performance

 

      In addition to the dramatic effect that strength-training programs can have on throwing velocity and the reduction of pain in the shoulder and elbow regions, these programs may also have a positive effect on an individual player’s offensive production, pitching production, or on the overall success of a team.  While there is very little to no research on these effects, there has been some scientific research done in regards to overall athletic conditioning and performance of baseball players.

      The purpose of a study conducted by Potteiger et al. was to examine the effects of two training methods on selected physiological and performance factors that were deemed important to successful performance in baseball by the researchers.  The researchers attempted to determine whether a weight/sprint conditioning program or an aerobic-dance conditioning program would significantly change selected body composition (BC), cardiovascular (CV) and performance (PF) variables in baseball players. Twenty-one collegiate baseball players participated in a 10-week conditioning program in addition to their normal baseball activities. Subjects were randomly assigned to either a weight/sprint (WS) or an aerobic-dance (AE) training group. The WS group performed strength and sprint training, while the AE group was involved in an aerobic dance program. Pre- and post-training measurements were taken of the following variables: height, weight, percent of body fat, lean body mass, lower body flexibility, aerobic power, anaerobic power, throwing velocity and 30-yard sprint time. 

      The WS group showed significant improvement in the PF variables. Anaerobic power increased 4.2 percent, while throwing velocity increased 3.0 percent after the WS training. No significant changes in the BC or CV variables were observed. The AE group produced significant differences in the BC variables. An 8.5 percent decrease was observed for levels of body fat, while lean body mass increased 2.1 percent after the aerobic-dance program. There were no significant changes in CV or PF variables in the AE group. There were no significant interactions between the WS and AE groups for any of the variables. The results indicated that a weight/sprint training program will improve PF variables related to baseball, while maintaining acceptable BC and CV components. Based on this information, it is suggested that baseball coaches use weight/sprint conditioning when training their players (Potteiger, et al., 1992).       

      In a study conducted from 1981 to 1987 by Hagerman, Starr, and Murray, players on a major league baseball team underwent physical fitness testing for the entire seven-year period, or for as long as they remained with the team.  The purpose was to evaluate each player’s fitness status and design individualized training programs for both the off- and in-seasons based on the test results.  Body composition, flexibility, aerobic capacity, anaerobic power, muscle strength, and muscle power were the fitness areas that were evaluated.  Results indicated that baseball players are highly skilled athletes whose muscle strength and anaerobic power are excellent, whose flexibility is better than average, but whose aerobic capacity is low.  A comprehensive training and education program produced significant improvements in all areas of fitness testing with the exception of aerobic capacity (Hagerman, et al., 1989).

 

Implementing Change

 

      Coaches, trainers, and athletes have slowly begun to acknowledge the value of strength training as it relates to improved skill performance in baseball.  In years past, it was thought that lifting weights would hinder a baseball player’s ability to pitch, throw, and hit.  Thanks to research and education, it is now known that strength training is not detrimental to a baseball player’s level of performance, and can actually improve and enhance his performance.  There are still some coaches, however, who do not believe that strength training can be useful when developing a baseball player’s skills.  Further research needs to be conducted to more closely examine the effects of strength training on a baseball player’s skill enhancement and performance.  Additionally, coaches need to be continually educated on the rapidly changing theories, ideas, and trends in strength training for baseball players.  Up-to-date knowledge and training techniques can enable coaches to implement appropriate strength-training programs which can lead to improved success of their team.

 

Summary

 

      It is evident by examining the existing research and data, that strength-training programs can have a positive effect on the variables important to a baseball player’s level of performance, and also aid in the reduction of arm and shoulder pain.  It is imperative that strength-training programs use particular exercises related to baseball-specific skills in order for the use of these programs to be effective in achieving the desired outcomes.  The research on this topic is still relatively new, and further research needs to be conducted to understand any far-reaching implications that strength-training programs may have on baseball players.

 

 

References

 

DeRenne, C., Ho, K., & Murphy, J.  (2001).  Effects of general, special, and specific resistance training on throwing velocity in baseball: A brief

review.  Journal of Strength and Conditioning Research, 15 (1), 148-156. 

 

Gardner, P.J. & Schwab, G.  (1998).  Preseason power training for baseball at rhodes college.  Strength and Conditioning Journal, 20 (2), 44-49.

 

Hagerman, F., Starr, L., & Murray, T.  (1989).  Effects of a long term fitness program on professional baseball players.  The Physician and Sports Medicine, 17 (4),  101-119.

 

International Fitness Professionals Association’s Health & Fitness Glossary.  (n.d.).  Retrieved May 15, 2002, from http://www.ifpa-fitness.com/Fitness-Glossary/fitness_glossary_a.htm

 

Lachowetz, T., Evon, J., & Pastiglione, J.  (1998).  The effect of an upper body strength program on intercollegiate baseball throwing velocity.  The Journal of Strength and Conditioning Research, 12 (2), 116-119.   

 

Lachowetz, T., Drury, D., Elliot, R., Evon, J., & Pastglione, J.  (1998).  The effect of an intercollegiate baseball strength program on the reduction of shoulder and elbow pain.  The Journal of Strength and Conditioning Research, 12 (1), 46-51.   

 

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Marshall, R. & Jacobs, D.  (2001).  Physical science.  Circle Pines, MN: American Guidance Service, Inc.

 

Murphy, J. & Forney, J.  (1997).  Complete conditioning for baseball.  Champaign, IL: Human Kinetics.

 

Musgrave, J.  (2001).  Big man on campus.  American Football Monthly, 7 (3), 16-19.

 

Netfit’s Health and Fitness Glossary.  (n.d.).  Retrieved May 15, 2002, from http://www.netfit.co.uk/glossa.htm

 

Newton, R. & McEvoy K.  (1994).  Baseball throwing velocity: A comparison of medicine ball training and weight training.  The Journal

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Odgers, S.  (1993).  Strength training benefits White Sox pitcher McDowell.  National Strength and Conditioning Journal, 15 (4), 50-54.

 

Panariello, R.  (1992).  Arm deceleration training for the baseball pitcher.  National Strength and Conditioning Journal, 14 (6), 19-25.

 

Potteiger, J., Williford, H., Blessing, D., Smidt, J.  (1992).  Effect of two training methods on improving baseball performance variables.  The Journal of Applied Sport Science Research, 6 (1), 2-6.

 

Shepard, G.  (1998).  Home run predictions come true.  Bigger Faster Stronger Magazine, Winter, 68-70.

 

Tracy, G., Tropp, H., & Friedl, A.  (1974).  Modern Physical Science.  New York: Holt, Rinehart, and Winston, Inc. 

 

Trygve.com’s dictionary of weightlifting, bodybuilding, and exercise terms and techniques.  (n.d.).  Retrieved May 15, 2002, from www.trygve.com/weights glossary.html

 

Watkinson, J.  (1997).  A strength, speed, power approach to improving throwing velocity in baseball.  Strength and Conditioning Journal, 19 (5), 42-47.

 

Weatherly, J. & Schinck, C.  (1996).  Concepts for baseball conditioning. Strength and Conditioning Journal, 18 (4), 32-39.