Though nutrition wasn’t the main focal point of this study, says Arciero, participants did follow a strict diet. Men and women in all groups met with a registered dietitian and were given a 12-week meal plan to follow.

On resistance training days, participants in all groups ate a small snack one hour before training. On stretching, endurance, and interval days, morning participants arrived fasted, but hydrated, and evening participants were also hydrated and fasted for four hours.