ABSTRACT:
Background/Objectives: The Anterior cruciate ligament injury is known to develop muscular weakness in the quadriceps. Especially, the weakness of the quadriceps muscle might be associated with increasing functional instability Protein supplementation can enhance the training outcomes of subjects, but it is not clear if there are benefits after ACL reconstruction. The aim of this study was to determine the effect of 12 weeks of rehabilitation exercise that only measured quadriceps muscle strength with supplementation of whey protein versus non supplementation. Methods/Statistical analysis: The thirty men (mean age: 25.4±6.1yr) who underwent ACL reconstruction were divided into two groups. The first group was proteins supplementation exercise group (PSG, n=15) and another group was non-protein supplementation exercise group (NPSG, n=15). All groups had gotten right on the rehabilitation exercise for 12 weeks after the surgery with ACL reconstruction via hamstring-tendon auto-graft. Outcomes were measured the quadriceps strength on either side by CSMI isokinetic testing device. Findings: PSG showed significantly improvement in quadriceps muscle strength compared with NPSG. In PSG, the quadriceps strength deficit reduced 37.4±16.8% to 22.5±6.5% at 60°/sec and 29.2±13.1% to 18.5±7.9% at 180°/sec whereas NPSG showed reduced by 36.1±15.6% to 28.5±8.8% at 60°/sec and 27.8±14.7 % to 21.9±9.3% at 180°/sec, respectively. Improvements/Applications: The combination of protein supplementation and exercise inanterior cruciate ligament reconstruction surgery has effective impact on quadriceps muscle strength.