Differences in PlayerLoad and pitch type in collegiate baseball players

ABSTRACT

PlayerLoad is derived from a tri-axial accelerometer device and is a measure of an athlete’s external training load. Tri-axial accelerometers (Optimeye S5, Catapult Sports, Melbourne, Australia) were worn by 25 collegiate pitchers during a pitching session. Pitches included fastballs, curve balls, sliders, and changeups. Peak and sum PlayerLoad were calculated for fastballs, curve balls, sliders, and changeups. Statistical analysis included paired t-tests (p < 0.01) and effect size indexes (ESI). Peak and sum PlayerLoad were higher for fastballs compared to changeups (N = 20; ESI_peak = 0.47, p= 0.001 and ESI_Sum = 0.13, p = 0.001, respectively). Peak and sum PlayerLoad were not different comparing fastball to curveball (N = 12; ESI_peak = 0.24, p = 0.050 and ESI_Sum<0.01, p = 0.106) and fastball to slider (N = 12; ESI_peak = 0.32, p = 0.088 and ESI_Sum = 0.02, p = 0.221). Fastball velocity (37.1 ± 2.1 m/s) differed from the changeup (33.8 ± 1.9 m/s; p < 0.001), curveball (32.2 ± 1.2; p < 0.001), and slider (33.8 ± 1.3 m/s; p < 0.001). Pitching workload may differ based on pitch type. Pitch counts may not capture true player fatigue due to variability in stresses resulting from different pitch types.

KEYWORDS:

• Baseball pitching
• pitch count
• throwing
• accelerometer
• PlayerLoad

Acknowledgments

The authors would like to thank Sophia Ulman, Steven Heer, Justin Losciale PT, DPT, and Jason Shutt PT, DPT for their help in data collection.

Disclosure statement

No potential conflict of interest was reported by the authors.