The effect of astaxanthin supplementation on performance and fat oxidation during a 40 km cycling time trial

This study aimed to investigate whether supplementation with 12 mg⋅day^-1 astaxanthin for 7 days can improve exercise performance and metabolism during a 40 km cycling time trial.

A randomised, double-blind, crossover design was employed.

Twelve recreationally trained male cyclists (VO_2peak: 56.5 ± 5.5 mL⋅kg^-1⋅min^-1, W_max: 346.8  ± 38.4 W) were recruited. Prior to each experimental trial, participants were supplemented with either 12 mg⋅day^-1 astaxanthin or an appearance-matched placebo for 7 days (separated by 14 days of washout). On day 7 of supplementation, participants completed a 40 km cycling time trial on a cycle ergometer, with indices of exercise metabolism measured throughout.

Time to complete the 40 km cycling time trial was improved by 1.2 ± 1.7% following astaxanthin supplementation, from 70.76 ± 3.93 min in the placebo condition to 69.90 ± 3.78 min in the astaxanthin condition (mean improvement = 51 ± 71 s, p = 0.029, g = 0.21). Whole-body fat oxidation rates were also greater (+0.09 ± 0.13 g⋅min^-1, p = 0.044, g = 0.52), and the respiratory exchange ratio lower (-0.03 ± 0.04, p = 0.024, g = 0.60) between 39-40 km in the astaxanthin condition.

Supplementation with 12 mg⋅day^-1 astaxanthin for 7 days provided an ergogenic benefit to 40 km cycling time trial performance in recreationally trained male cyclists and enhanced whole-body fat oxidation rates in the final stages of this endurance-type performance event.