ISOKINETIC EVALUATION OF THE SHOULDER ROTATORS OF COMPETITIVE TRAP SHOOTERS282

Abstract

Seventeen male Trap shooters exposed to chronic shotgun recoil (1000+ targets per month for five years or more) participated in an investigation aimed to establish the effects of chronic recoil upon the shoulder girdle musculature. Tests included bilateral goniometric measurements of shoulder range of motion (ROM) and isokinetic evaluation of peak torque (PT) strength during internal and external shoulder rotation (60, 180, and 300 deg·s-1). External/Internal ratio of muscle balance (ER/IR) and Time Rate of Tension Development (TRTD) were calculated from measurements of PT. Paired t-tests revealed significant differences between shoulders ROM (nondominant > dominant: p < 0.05) during internal rotation (IR) and PT generated during IR at 300 deg·s-1(nondominant < dominant; p < 0.05). No differences were found when comparing both shoulders for external rotation (ER) PT and TRTD (IR, ER). However, regardless of shoulder or rotation direction (IR, ER), PT and TRTD decreased with increments in velocity (60 > 180 > 300 deg·s-1; p < 0.05). Contrary to PT or TRTP, both shoulders showed increments in ER/IR along with testing velocity (60 < 180 < 300 deg·s-1; p < 0.05). Pearson product-moment correlations established significant relationships for both shoulders between ROM during IR and PT generated during external rotation (r=.63-.64; p < 0.05). It was concluded that chronic shotgun recoil influences shoulder rotational ROM and ER/IR ratio but does not seem to affect rotational peak torque strength.