Intake of Protein Plus Carbohydrate during the First Two Hours after Exhaustive Cycling Improves Performance the following Day

PLoS One. 2016 Apr 14;11(4):e0153229. doi: 10.1371/journal.pone.0153229. eCollection 2016.


Intake of protein immediately after exercise stimulates protein synthesis but improved recovery of performance is not consistently observed. The primary aim of the present study was to compare performance 18 h after exhaustive cycling in a randomized diet-controlled study (175 kJ·kg(-1) during 18 h) when subjects were supplemented with protein plus carbohydrate or carbohydrate only in a 2-h window starting immediately after exhaustive cycling. The second aim was to investigate the effect of no nutrition during the first 2 h and low total energy intake (113 kJ·kg(-1) during 18 h) on performance when protein intake was similar. Eight endurance-trained subjects cycled at 237±6 Watt (~72% VO2max) until exhaustion (TTE) on three occasions, and supplemented with 1.2 g carbohydrate·kg(-1)·h(-1) (CHO), 0.8 g carbohydrate + 0.4 g protein·kg(-1)·h(-1) (CHO+PRO) or placebo without energy (PLA). Intake of CHO+PROT increased plasma glucose, insulin, and branch chained amino acids, whereas CHO only increased glucose and insulin. Eighteen hours later, subjects performed another TTE at 237±6 Watt. TTE was increased after intake of CHO+PROT compared to CHO (63.5±4.4 vs 49.8±5.4 min; p<0.05). PLA reduced TTE to 42.8±5.1 min (p<0.05 vs CHO). Nitrogen balance was positive in CHO+PROT, and negative in CHO and PLA. In conclusion, performance was higher 18 h after exhaustive cycling with intake of CHO+PROT compared to an isocaloric amount of carbohydrate during the first 2 h post exercise. Intake of a similar amount of protein but less carbohydrate during the 18 h recovery period reduced performance.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / blood
  • Analysis of Variance
  • Athletic Performance / physiology*
  • Bicycling / physiology*
  • Blood Glucose / metabolism
  • Creatine Kinase / blood
  • Dietary Carbohydrates / administration & dosage
  • Dietary Carbohydrates / pharmacology*
  • Dietary Proteins / administration & dosage
  • Dietary Proteins / pharmacology*
  • Double-Blind Method
  • Exercise Test
  • Fatty Acids, Nonesterified / blood
  • Glucagon / blood
  • Glycerol / blood
  • Humans
  • Insulin / blood
  • L-Lactate Dehydrogenase / blood
  • Male
  • Myoglobin / blood
  • Oxygen Consumption / drug effects
  • Oxygen Consumption / physiology
  • Physical Endurance / drug effects*
  • Physical Endurance / physiology
  • Time Factors
  • Young Adult


  • Amino Acids
  • Blood Glucose
  • Dietary Carbohydrates
  • Dietary Proteins
  • Fatty Acids, Nonesterified
  • Insulin
  • Myoglobin
  • Glucagon
  • L-Lactate Dehydrogenase
  • Creatine Kinase
  • Glycerol

Grant support

The study was funded by Norwegian School of Sport Sciences.