Throwing training load in baseball, grip strength, and reach test results

Summary of an article looking at the influence of the number of throws and overall training load on grip strength and shoulder range of motion in male collegiate baseball players.

Who

18 players aged 20.1±1.3 years from 2 collegiate baseball teams (USA).

Design

Longitudinal repeated-measures (pre-season, 4, 8,12, 16 weeks) design.

Outcome measures

• training load (duration of training in minutes, throw count, RPE for the whole body and arm-specific) via daily survey used to calcuate ACWR

ACWR – Acute:chronic workload ratio = a ratio of traning load acummulated over the recent week and the training load accumulated over the previous 4 weeks

• glenohumeral range of motion via overhead and behind-the-back reach tests (measurement tape over the spine with 0 at C7, non-tested arm on the hip, tested arm reaching either overhear or behind the back)
• grip strength (in 3 positions: shoulder in neutral and elbow flexed at 90°, shoulder abducted to 90° and elbow flexed at 90°, shoulder abducted and externally rotated to 90° and elbow flexed 90°) via handheld compression load-cell dynamometer

Main results

• Low arm-specific acute:chronic workload ratio (ACWR) group decreased their behind-the-back scores. For overhead reach test, the moderate training load group increased reach distance comparing to low and high groups. The results did not differ between dominant and non-dominant arm.
• Grip strength increased in the low arm-specific ACWR group compared to moderate and high groups.

Take home message

Original article

Pexa B, Ryan ED, Blackburn JT, Padua DA, Garrison JC, Myers JB. Influence of Baseball Training Load on Clinical Reach Tests and Grip Strength in Collegiate Baseball Players. Journal of Athletic Training. 2020 Aug 28.