We recently demonstrated body fat %, fast ball velocity, and RPE were significant predictors of valgus torque in NCAA baseball pitchers. Even though changes in hyperemic-induced limb volume are associated with acute, repetitive pitching performance, possibly indicating approaching dominant elbow soft-tissue risk, no investigation, to our knowledge, has examined relationships between performance, biometric, and throwing-limb volume in collegiate pitchers.
PURPOSE: To quantify the relationship between pitching performance, subject biometrics, and hyperemic-induced changes in collegiate baseball pitchers during game-simulated pitching sessions of 40, 80, or 120 pitches.
METHODS: Following informed consent, 5 male subjects (x̄ age = 18.8 ± 0.8 years; x̄ BMI = 27.6 ± 1.8; x̄ body fat % = 22.9 ± 6.2; x̄ throwing velocity = 80.4 ± 1.8 mph) were block-assigned to groups of 40, 80, or 120 pitches. Bouts consisted of 10 pitches (~20s between pitches) delivered from an artificial mound with 1-2 mins rest between bouts. HR and RPE were recorded immediately following each 10-pitch bout. A MOTUS sensor and compression sleeve measured elbow valgus torque. A Stalker Sport II Radar Gun measured fastball velocity. Pre-test and post-test upper- and lower-extremity limb girths were measured, signifying reactive hyperemia. Wilcoxon non-parametric testing determined pre- to post-test differences. Pearson correlation identified relationships between variables. Alpha was set at p ≤ 0.05.
RESULTS: No group differences were found on any performance, biometric, demographic, or hemodynamic variable. HR (72.6 ± 8.3bpm vs. 97.6 ± 10.0bpm, p = 0.02) and dominant forearm limb girth (29.4 ± 1.5cm vs. 30.9 ± 1.5cm, p = 0.04) increased from pre-test to post-test for subjects combined. Significant correlations were found for: pitching volume & post-test HR (r = 0.90, p = 0.039); post-test dominant upper arm circumference & RPE (r = 0.89, p = 0.042), and; valgus torque % change & pitching volume (r = 0.91, p = 0.031).
CONCLUSIONS: Forearm limb girth increased for subjects combined, and; given this metric’s indication of reactive hyperemia, future research focused on elucidating and quantifying the biological components of the tissue (compartments), as well as their contribution to performance- and/or injury-specific outcomes, is warranted.