
Doctors said that astaxanthin, the bright red carotenoid in salmon and shrimp, increases muscle enzymes that help convert fat to energy. To test this theory, 14 competitive cyclists took 4 mg of astaxanthin per day or a placebo.
After 28 days, the bikers fasted and rode for two hours to deplete stored carbs, and then took a 12-mile time trial. The astaxanthin group completed the trial much faster than the placebo group.