Test-retest reliability of power, pinch, and tripod grip strengths in male baseball players: a preliminary study

Since baseball players must grip and pinch the ball, grip strength is paramount. However, current assessments on various grip types need to be more comprehensive. This study aimed to determine the test-retest reliability of different handgrip strengths measured by a dynamometer connected to a player’s smartphone. Sixty male baseball players sponsored by secondary schools (middle- and high-schools) or colleges varying in age (12–22 years) were selected as participants. For male baseball players, three types of grip strengths were evaluated using a dynamometer and smartphone application: power, pinch, and tripod grip. The test was conducted thrice for each grip. Overall grip strength measurements showed slight decreases across tests and tended to increase with academic grade level. Tests 1 and 2 indicated good-to-excellent retest reliability for three grip strength positions by determining their intraclass correlation coefficients (ICCs) (middle-school power grip: 0.917 (0.644–0.973); collegiate pinch grip: 0.920 (0.770–0.970); high-school tripod grip: 0.929 (0.728–0.976)). In addition, these results determined moderate reliability compared to other grip strengths in the three groups (middle-school tripod grip from Tests 1 and 2: 0.779 (0.428–0.914); collegiate power grip from Tests 2 and 3: 0.738 (0.360–0.895)). This study concluded that the studied grip strength tests are reliable measurements, with an acceptable margin of error, for male baseball players from childhood to adulthood. Therefore, these handgrip strengths may be used as preliminary values to help discipline and rehabilitate baseball players and other athletes.