The Effects of Astaxanthin on Physiological Anti-fatigue and Sports Performance: an Integrated Study From the Application of Laboratory Human Sports Platform to Simulated Competitions

First Year: In this study, participants will be randomly assigned to either the AST group or the placebo group and will take AST supplements or a placebo (20 mg/day) for 8 weeks. You will not know whether you have been assigned to the supplement group or the placebo group. After the first trial in each group, there will be a 14-day washout period, after which the two groups will switch places to conduct the second trial. Seven days before the exercise performance test, all participants will undergo a maximal oxygen uptake (VO₂ max) test, and the intensity of the single-session cycling challenge will be calculated based on this measurement. Participants will fast for 12 hours prior to the day of the exercise challenge. They will report to the laboratory at 7:00 AM on the day of the test for body composition measurements, followed by consumption of a light meal (300 kcal) accompanied by an AST supplement or placebo capsule, and a 1-hour rest period. One hour after taking the supplement capsule, participants performed a 5-minute cycling warm-up on a human motion platform designed by the PI's laboratory, followed by a single 60-minute cycling exercise at 70% VO2max, maintaining a cadence of 60 rpm throughout. After completing the exercise challenge, participants consumed a meal (60% carbohydrates, 25% fat, 15% protein) tailored to their body weight. Then, 3 hours into the recovery period, they underwent an anaerobic power test and a subsequent exercise-to-exhaustion (Time to Exhaustion, TTE) challenge at 75% VO2max, with exercise performance times recorded. Additionally, blood and gas samples were collected before the first cycling challenge, at the 30-minute mark during the challenge, immediately after exercise, every hour during the recovery period, and after the subsequent exercise-to-exhaustion test. Following a brief recovery period (3 hours), participants performed a 30-second anaerobic power test. After a 5-minute rest, they proceeded to a 75% cycling test to exhaustion. The experimental design included administering the Profile of Mood States (POMS) questionnaire before and after each exercise challenge to assess participants' emotional tendencies during exercise. The experimental procedures and exercise performance tests for both trials were identical to those described above.

Year 2: This study employs a randomized, single-blind, crossover design. Participants will be randomly assigned to groups to receive either an AST supplement or a placebo (12 mg/day) for 4 weeks, and you will not know whether you have been assigned to the supplement or placebo group. After the first trial is completed for each group, there will be an 8-week washout period, after which the two groups will switch places to conduct the second trial. This simulated badminton competition consists of 5 matches over 5 consecutive days, with a 24-hour rest period between each match. All participants will follow a controlled diet for 3 days prior to the simulated badminton competition trial. Participants will fast starting 12 hours before the day of the simulated competition. They will report to the laboratory at 7:00 AM on the day of the test for body composition measurements, followed by consumption of a light meal (300 kcal) paired with an AST capsule or placebo. After a 3-hour rest period, the first blood draw will be performed, followed by a badminton-specific warm-up (15 minutes). Following the research assistant's instructions, participants first performed a badminton-specific warm-up for 10 to 15 minutes. Subsequently, in accordance with the latest international competition format "3 x 21-point system" established by the Badminton World Federation (Badminton World Federation, BWF) in 2006, participants were paired up to complete a simulated badminton match using the "3 x 21-point system," with a 1-minute-30-second rest period before the start of the next game. Participants were allowed to hydrate during the simulated badminton matches. Finally, to better simulate the scenario where badminton players may need to prepare for the next match immediately after completing one, the final aerobic capacity test involved a badminton-specific incremental endurance test. Participants were allowed to stop the test upon reaching exercise exhaustion, and the total exercise duration and power output were recorded. The experimental procedures and performance assessment items for both trials were the same as described above. Sport-specific physical performance assessments included upper-body grip strength, the Counter Movement Jump (CMJ), and 10-second anaerobic power.