David J. Szymanski

Contributing factors for increased bat swing velocity.

Bat swing velocity is an important characteristic of successful hitters in baseball and softball. The purpose of this literature review is threefold. First, before describing what components and training methods have been investigated to improve bat swing velocity, it is necessary to discuss the importance of bat swing velocity and batted-ball velocity. The second purpose is to discuss bat weight during on-deck circle warm-up, bat weight during resistance training, resistance training with an overload of force, performance of additional supplemental resistance exercises, the relationship between strength, power, lean body mass, and angular velocity and bat swing velocity, and the relationship between improvements in strength, power, lean body mass, and angular velocity and improvements in bat swing velocity. The third purpose of this review is to recommend some practical applications based on research results.

Effect of various warm-up devices on bat velocity of intercollegiate baseball players.

Szymanski, DJ, Beiser, EJ, Bassett, KE, Till, ME, Medlin, GL, Beam, JR, and DeRenne, C. Effect of various warm-up devices on bat velocity of intercollegiate baseball players. J Strength Cond Res 25(2): 287-292, 2011-A variety of warm-up devices are available to baseball players to use before their game at-bat. Past baseball research evaluating warm-up devices indicates that implements that are ±12% of standard game bat weight produce the greatest bat velocities for high school and intercollegiate players. The purpose of this study was to examine the effect of various warm-up devices on bat velocity (BV) of intercollegiate baseball players. Twenty-two Division I intercollegiate baseball players (age = 20.0 ± 1.5 years, height = 182.6 ± 8.3 cm, body mass = 91.4 ± 11.4 kg, lean body mass = 78.8 ± 8.9 kg, % body fat = 13.6 ± 3.8) participated in a warm-up with 1 of 10 weighted devices on separate days. Each of the 10 testing sessions consisted of a standardized warm-up, 3 dry swings as hard as possible with the assigned warm-up device, 2 comfortable dry swings with a standard game baseball bat followed by 3 game swings (20-second rest between swings) while hitting a baseball off of a batting tee with the same standard game baseball bat. Results indicated that there were no statistically significant differences in BV after using any of the 10 warm-up devices. For male intercollegiate baseball players, results indicate that warm-up devices varying from 623.7 to 2,721.5 g (22-96 oz.) did not change mean BV of a standard game baseball bat, suggesting that intercollegiate players can use any of the 10 warm-up devices in the on-deck circle and maintain their BV. Therefore, personal preference as to which warm-up implement to use in the on-deck circle is advised.

The relation between anthropometric and physiological variables and bat velocity of high-school baseball players before and after 12 weeks of training.

Szymanski, DJ, Szymanski, JM, Schade, RL, Bradford, TJ, McIntyre, JS, DeRenne, C, and Madsen, NH. The relation between anthropometric and physiological variables and bat velocity of high school baseball players before and after 12 weeks of training. J Strength Cond Res 24(11): 2933-2943, 2010-The purpose of this article was to investigate the relation between anthropometric and physiological variables to linear bat swing velocity (BV) of 2 groups of high-school baseball players before and after completing a 12-week periodized resistance exercise program. Participants were randomly assigned to 1 of 2 training groups using a stratified sampling technique. Group 1 (n = 24) and group 2 (n = 25) both performed a stepwise periodized resistance exercise program and took 100 swings a day, 3 d·wk−1, for 12 weeks with their normal game bat. Group 2 performed additional rotational and full-body medicine ball exercises 3 d·wk−1 for 12 weeks. Fourteen variables were measured or calculated before and after 12 weeks of training. Anthropometric and physiological variables tested were height, body mass, percent body fat, lean body mass (LBM), dominant torso rotational strength (DTRS) and nondominant torso rotational strength (NDTRS), sequential hip-torso-arm rotational strength measured by a medicine ball hitters throw (MBHT), estimated 1 repetition maximum parallel squat (PS) and bench press (BP), vertical jump (VJ), estimated peak power, angular hip velocity (AHV), and angular shoulder velocity (ASV). The baseball-specific skill of linear BV was also measured. Statistical analysis indicated a significant moderately high positive relationship (p ≤ 0.05) between prelinear BV and pre-NDTRS for group 1, pre-LBM, DTRS, NDTRS, peak power, and ASV for group 2; moderate positive relationship between prelinear BV and preheight, LBM, DTRS, peak power, BP, PS, and ASV for group 1, preheight, body mass, MBHT, BP, and PS for group 2. Significantly high positive relationships were indicated between postlinear BV and post-NDTRS for group 1, post-DTRS and NDTRS for group 2; moderately high positive relationships between postlinear BV and post-LBM, DTRS, peak power, BP, and PS for group 1, postheight, LBM, VJ, peak power for group 2; moderate positive relationships between postlinear BV and postheight, body mass, MBHT, and VJ for group 1, postbody mass, MBHT, BP, PS, and ASV for group 2. Significantly low positive relationships were indicated between prelinear BV and prebody mass, MBHT, and VJ for group 1, pre-VJ and AHV for group 2; postlinear BV and post-AHV for group 2. These data show that significant relationships do exist between height, body mass, LBM, rotational power, rotational strength, lower body power, upper and lower body strength, AHV, and ASV to linear BV of high-school baseball players. Strength coaches may want to consider using this information when designing a resistance training program for high-school baseball players. Those recruiting or scouting baseball players may want to use this information to further develop ways of identifying talented players. However, one should be cautious when interpreting this information when designing strength training programs for high-school baseball players to increase linear BV.

College Baseball/Softball Periodized Torso Program

David J. Szymanski, MEd, CSCSGregory A. Fredrick, CSCSDepartment of Health and Human PerformanceAuburn UniversityKeywords: baseball; softball; periodization; torso; abdominals; low back.WHEN DESIGNING A SPORT-specific training program for base-ball/softball (BA/SB), it is impor-tant to implement a systematictotal body conditioning programthat will prepare the athlete for thedemands of the sport. A year-round periodized program shouldinclude a variety of upper- andlower-body exercises, and the in-tensity and volumes of exerciseshould change as the season ap-proaches. The exercises completedby the athletes should becomemore specific to the movementsinvolved in the sport. However,many BA/SB athletes perform tra-ditional trunk exercises that con-sist of continuous sets (rangingfrom 3 to 8 minutes) throughoutthe entire year. This type of repeti-tive torso training for the BA/SBathlete is not specific to the move-ments of the 2 sports, nor will itimprove the strength and power ofthe athletes. Torso movementsthat mimic the explosive, ballistic,and dynamic movements of swing-ing a bat or throwing a ball shouldbe performed instead.The purpose of this article is todescribe and illustrate how thestrength and conditioning special-ist or baseball/softball coach candevelop the powerful, twisting,and functional strength needed toimprove a college BA/SB player’sability to field, throw, and hit. Ad-ditionally, this information shouldpositively affect injury risk andfurther educate those who aretraining for the explosive needs ofthe BA/SB athlete.

Effects of Various Warm-Up Devices and Rest Period Lengths on Batting Velocity and Acceleration of Intercollegiate Baseball Players

Abstract Wilson, JM, Miller, AL, Szymanski, DJ, Duncan, NM, Andersen, JC, Alcantara, ZG, Morrison, TJ, and Bergman, CJ. Effects of various warm-up devices and rest period lengths on batting velocity and acceleration of intercollegiate baseball players. J Strength Cond Res 26(9): 2317–2323, 2012—It is common among competitive baseball players to swing bats while in the batters box in an attempt to improve their batting performance. Players use bats of different weights during this time, and only a few studies have evaluated the optimal bat weight to increase performance. Previous studies have not investigated the optimal rest period after a warm-up with bats of varying weights. Therefore, we tested the peak bat velocity of 16 National Collegiate Athletic Association Division II intercollegiate baseball players at 1, 2, 4, and 8 minutes, after warming up with bats of 5 different weights. Measured variables were peak bat velocity at peak acceleration (PVPA), peak bat velocity of the swing (PV), peak bat acceleration (PA), and time to reach peak acceleration (TPA) using a chronograph, which measured the batting velocity in real time every 10 milliseconds throughout the swing. A repeated measure analysis of variance was run to assess group, time, and group by time interactions. If any main effects were found, a Tukey post hoc was employed to locate differences. There were significant (p ⩽ 0.05) time effects for PVPA, PV, and PA but not for TPA. The PVPA, PV, and PA all increased over time, peaking from 4 to 8 minutes. There were no significant differences in any of the variables among the 5 bat weights used in the warm-up (p > 0.05). However, there were significant differences in PVPA, PV, and PA after 2, 4, and 8 minutes of rest compared with the preexperimental warm-up and 1-minute post–warm-up. From a practical standpoint, batters should warm up early and quickly in the batters box to maximize the amount of recovery time before they swing at the plate. In addition, batters may want to take their time getting ready at the plate or take some pitches while at-bat in an attempt to maximize performance. Alternatively, the data imply that pitchers should throw their fastest pitch near the beginning of the at-bat to correspond with the potentially slower bat speeds of the batter.

Validity of 2 Skinfold Calipers in Estimating Percent Body Fat of College-aged Men and Women

Beam, JR, and Szymanski, DJ. Validity of 2 skinfold calipers in estimating percent body fat of college-aged men and women. J Strength Cond Res 24(12): 3448-3456, 2010-There is a need for cost-effective techniques that accurately predict percent body fat (%BF) and require little skill to administer. There are 2 commercially available skinfold calipers, 1 digital and the other self-administered, that claim to accurately predict %BF. The primary purpose of this study was to validate these calipers using dual-energy x-ray absorptiometry (DXA) as a reference method in a sample of college-aged men and women. A secondary purpose of this study was to compare the validity of these calipers to the validity of arm-to-arm bioempedance analysis (BIA) (Omron, Shelton, Connecticut, U.S.A.), leg-to-leg BIA (Tanita, Arlington Heights, Illinois, U.S.A.), and 3-site skinfold equations (SUM3) using DXA as a reference method. Fifty college students (25 men and 25 women) from a kinesiology department who ranged in fitness levels volunteered to have %BF measured by the digital and self-administered skinfold calipers, Omron, Tanita, and SUM3. The digital and self-administered skinfold calipers had the poorest group predictive accuracy for the men and women (total error ranged from 7.9 to 10.9%BF) when compared to the other field methods. The digital skinfold caliper had good individual predictive accuracy in the men (95% limits of agreement [LOA] = ± 6.4%BF) and women (95% LOA = ± 4.9%BF) when compared to the other field methods. However, the self-administered skinfold caliper had poor individual predictive accuracy for the men (LOA = ± 8.6%BF) and the women (LOA = ± 7.5%BF) when compared to the other field methods. Compared to DXA, Tanita, Omron, and SUM3, we would not recommend using the digital or self-administered skinfold calipers for estimating %BF in college-aged men and women with similar body composition as the men and women in this study. We recommend using the SUM3 to estimate %BF.

Effects of Three Recovery Protocols on Range of Motion, Heart Rate, Rating of Perceived Exertion, and Blood Lactate in Baseball Pitchers During a Simulated Game.

Abstract Warren, CD, Szymanski, DJ, and Landers, MR. Effects of three recovery protocols on range of motion, heart rate, rating of perceived exertion, and blood lactate in baseball pitchers during a simulated game. J Strength Cond Res 29(11): 3016–3025, 2015—Baseball pitching has been described as an anaerobic activity from a bioenergetics standpoint with short bouts of recovery. Depending on the physical conditioning and muscle fiber composition of the pitcher as well as the number of pitches thrown per inning and per game, there is the possibility of pitchers fatiguing during a game, which could lead to a decrease in pitching performance. Therefore, the purpose of this study was to evaluate the effects of 3 recovery protocols: passive recovery, active recovery (AR), and electrical muscle stimulation (EMS) on range of motion (ROM), heart rate (HR), rating of perceived exertion (RPE), and blood lactate concentration in baseball pitchers during a simulated game. Twenty-one Division I intercollegiate baseball pitchers (age = 20.4 ± 1.4 years; height = 185.9 ± 8.4 cm; weight = 86.5 ± 8.9 kg; percent body fat = 11.2 ± 2.6) volunteered to pitch 3 simulated 5-inning games, with a maximum of 70 fastballs thrown per game while wearing an HR monitor. Range of motion was measured pre, post, and 24 hours postpitching for shoulder internal and external rotation at 90° and elbow flexion and extension. Heart rate was recorded after each pitch and after every 30 seconds of the 6-minute recovery period. Rating of perceived exertion was recorded after the last pitch of each inning and after completing each 6-minute recovery period. Immediately after throwing the last pitch of each inning, postpitching blood lactate concentration (PPLa−) was measured. At the end of the 6-minute recovery period, before the next inning started, postrecovery blood lactate concentration (PRLa−) was measured. Pitchers were instructed to throw each pitch at or above 95% of their best-pitched fastball. This was enforced to ensure that each pitcher was throwing close to maximal effort for all 3 simulated games. All data presented represent group mean values. Results revealed that the method of recovery protocol did not significantly influence ROM (p > 0.05); however, it did significantly influence blood lactate concentration (p < 0.001), HR (p < 0.001), and RPE (p = 0.01). Blood lactate concentration significantly decreased from postpitching to postrecovery in the EMS recovery condition (p < 0.001), but did not change for either the active (p = 0.04) or the passive (p = 0.684) recovery conditions. Rating of perceived exertion decreased from the postpitching to postrecovery in both the passive and EMS recovery methods (p < 0.001), but did not decrease for AR (p = 0.067). Heart rate decreased for all conditions from postpitching to postrecovery (p < 0.001). The use of EMS was the most effective method at reducing blood lactate concentration after 6 minutes of recovery during a simulated game (controlled setting). Although EMS significantly reduced blood lactate concentrations after recovery, blood lactate concentrations after pitching in the simulated games were never high enough to cause skeletal muscle fatigue and decrease pitching velocity. If a pitcher were to throw more than 14 pitches per inning, throw more total pitches than normal per game, and have blood lactate concentrations increase higher than in the simulated games in this study, the EMS recovery protocol may be beneficial to pitching performance by aiding recovery. This could potentially reduce some injuries associated with skeletal muscle fatigue during pitching, may allow a pitcher throw more pitches per game, and may reduce the number of days between pitching appearances.

Relationships Between Sports Performance Variables and Bat Swing Velocity of Collegiate Baseball Players

Baseball is an anaerobic, power sport. Position players need to perform the skill of hitting explosively to generate bat speed. Greater bat speed has been described as one of the most important traits of successful hitters. However, if a coach or scout was only given the results from fitness and performance tests, could they predict who might have greater bat speed? PURPOSE: To determine the relationship of various sports performance variables to bat swing velocity (BV) of college baseball players. METHODS: Twenty-two Division I college baseball players (age = 20.06 1.5 yr) participated in this study. Tests included percent (%) body fat (Tanita bioelectrical impedance device), height, body mass, lean body mass, dominant and non-dominant grip strength (Jamar hydraulic dynamometer), rotational power (6 lb medicine ball side toss), upper body strength (1RM bench press and 1-arm dumbbell row), lower body strength (1RM parallel squat), leg power (vertical jump), peak power, and BV (SETPRO SPRT5A chronograph). Correlation coefficients were calculated for all variables by utilizing a correlation matrix from raw scores. RESULTS: Statistical analysis indicated a significant and moderately high positive relationship (p , 0.05) between BV and dominant grip strength (r = 0.61). Significant and moderately positive relationships were indicated between BV and nondominant grip strength (r = 0.59), body mass (r = 0.53), peak power (r = 0.51), 1-arm dumbbell row (r = 0.51), lean body mass (r = 0.50), and parallel squat (r = 0.41). Significant and low positive relationships were indicated between BV and height (r = 0.37), % body fat (r = 0.25), medicine ball side toss (r = 0.25), and bench press (r = 0.21). CONCLUSIONS: These data suggest that significant relationships do exist between sports performance variables and BV, but one cannot interpret this to mean a cause and effect relationship. Other variables, such as hitting mechanics and bat properties (mass and moment of inertia), are also important in producing greater BV. PRACTICAL APPLICATIONS: Strength and conditioning coaches wanting to improve player’s BV should design sport-specific programs to develop strength, peak power, lean body mass, and rotational power.