PGC-1α mRNA expression for carbohydrate (CHO) and carbohydrate and whey protein isolate trials (CHO + WPI) following 16 day dietary intervention and exercise trial. Muscle biopsies were taken at rest, another following 60 min cycling at 70% VO2 max (70%), time to fatigue at 90% VO2 max (90%) and at the end of 6 h recovery (6 h recovery). CHO + WPI trial was significantly lower at rest, following cycling at 70% and 90% VO2 max, compared to 6 h recovery (# P < 0.05). After 6 h of recovery the CHO + WPI trial was significantly increased compared to CHO trial (^P < 0.05). Values are mean ± SEM (n = 6).