EFFECT OF AGE ON ANTHROPOMETRIC AND PHYSICAL PERFORMANCE MEASURES IN PROFESSIONAL BASEBALL PLAYERS GERALD T. MANGINE, 1 JAY R. HOFFMAN, 1 MAREN S. FRAGALA, 1 JOSE VAZQUEZ, 2 MATTHEW C. KRAUSE, 3 JAVAIR GILLETT, 4 AND NAPOLEON PICHARDO 2 1 Sport and Exercise Science, University of Central Florida, Orlando, Florida; 2 Texas Rangers Baseball Club, Arlington, Texas; 3 Cincinnati Reds Baseball Club, Cincinnati, Ohio; and 4 Detroit Tigers Baseball Club, Detroit, Michigan ABSTRACT Mangine, GT, Hoffman, JR, Fragala, MS, Vazquez, J, Krause, MC, Gillett, J, and Pichardo, N. Effect of age on anthropometric and physical performance measures in professional baseball play- ers. J Strength Cond Res 27(2): 375–381, 2013—The pur- pose of this study was to investigate age-related changes in anthropometric and performance variables in professional baseball players. Baseball players (n = 1,157) from several professional baseball organizations were categorized into 7 cohorts based upon age. All adolescent athletes were catego- rized as age group 1 (AG1), whereas the next 5 groups (AG2– AG6) consisted of players 20–22, 23–25, 26–28, 29–31, and 31–34 years, respectively. The final group (AG7) comprised athletes $35 years. All performance assessments were part of the athlete’s normal preseason training camp testing routine. Field assessments were used to analyze lower-body power, speed, agility, grip strength, and body composition. The players were heaviest between the ages of 29 and 31 (AG5), and their body mass in that age group was 10.1% (p = 0.004) greater than that of AG1. A 7.0% increase (p = 0.000) in lean body mass occurred between AG1 and AG5. No differences in 10-yd sprint times or agility were seen across any age group or position. A 2.0 seconds (p = 0.001) slower run time for the 300-yd shuttle was seen between AG4 and AG5 for all posi- tions combined. Elevations in grip strength were seen at AG4 compared with AG1 (p = 0.001) and AG2 (p = 0.007) for all positions combined. No other differences were noted. Lower- body power was increased for all positions combined from AG1 to AG3 (p = 0.007). This pattern was similar to that observed in position players, but a 12.4% decrease (p = 0.024) in VJMP was seen between AG7 and AG5 in pitchers. Results of this study indicate that lower-body power is maintained in baseball players until the age of 29–31, whereas speed, agility, and grip strength are maintained in players able to play past the age of 35 years. Age-related differences observed in this study suggest that athletes focus on their strength and conditioning programs to extend the length of their profes- sional careers. KEY WORDS athletes, strength, vertical jump, power, speed, agility INTRODUCTION R ecent investigations have demonstrated that size, strength, power, and speed are associated with successful baseball performance. Hoffman et al. (11) examining professional baseball players reported that lean body mass (LBM), lower-body jump power, and grip strength were significantly correlated with home runs, total bases, and slugging percentage, whereas significant correlations were also observed between 10-yd sprint time, agility (proagility test), and stolen bases. Others, examining high school and college athletes, have suggested that power (lower body) is positively associated with throw- ing velocity, bat speed, and batted-ball velocity (18). Addi- tionally, the importance of strength, power, and agility for baseball-specific performance (batting and fielding) has been reported in Japanese collegiate players (15). The results from these studies are consistent with the concept that strength, power, and speed are associated with greater success in baseball and provides evidence to support the anecdotal beliefs raised during baseball’s “steroid era” that stronger, more powerful athletes were dominating base- ball’s statistical categories (20). During this recent “era,” baseball performance by athletes in their 30’s were consid- ered to be statistical anomalies that may have been elevated by the use of illegal performance-enhancing drugs. As a result of the inclusion of rigid drug testing, it was believed that the performance levels that were seen in previous seasons would decline because of the potential decrease in strength, power, and other physical performance attributes that may have been related to illegal performance-enhancing drug use, Address correspondence to Jay R. Hoffman, Jay.hoffman@ucf.edu. 27(2)/375–381 Journal of Strength and Conditioning Research Ó 2013 National Strength and Conditioning Association VOLUME 27 | NUMBER 2 | FEBRUARY 2013 | 375 Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.