RESUMEN
PURPOSE: The purpose of this study was to investigate the changes on alpine skiers' body composition, anaerobic power, isokinetic knee strength and muscle balance ratio (hamstring to quadriceps [HQ] ratio) before and after winter season. METHODS: The subjects of this study was 22 elite alpine skier, aged 16–20 years. Participants were divided into two groups (male, 12; female, 10). The study conducts a periodization training program in the winter season for 4 months. The data processing of this study was analyzed by paired t-test, using SPSS 21.0 statistics program. RESULTS: There was significance on fat free mass in male group (p < 0.05); there was significance on anaerobic power and average power in female group (p < 0.01), and fatigue index significantly increased in male group (p < 0.05). There was significance on extension power of male group and flexion power of female group in 30°/sec. There was significance on extension power of both groups in 180°/sec (p < 0.05). There was significant increase on flexion power of male group in 240°/sec (p < 0.01). There was significant increase on H/Q% of female right side in 30°/sec (p < 0.01). There was significance on right side of both groups in 180°/sec (p < 0.05). There were significances on right and left side of both groups in 240°/sec (male, p < 0.01; female, p < 0.05). CONCLUSION: Therefore, this study suggests that the periodization training should be important to maintain and to develop seasonal condition of alpine skiers.