Addition of Caffeine to a Carbohydrate Feeding Strategy Prior to Intermittent Exercise

Int J Sports Med. 2020 Aug;41(9):603-609. doi: 10.1055/a-1121-7817. Epub 2020 Apr 6.

Abstract

The ergogenic effect of caffeine is well established, although no investigations providing a high carbohydrate feeding strategy (pre-exercise meal=2 g/kg BM) co-ingested with caffeine exist for soccer. This investigation examines the effect of caffeine in addition to a pre-exercise carbohydrate meal and drink mid-way through a soccer simulation. Eight recreational soccer players completed an 85-minute soccer simulation followed by an exercise capacity test (Yo-yo Intermittent Endurance test level 2) on two occasions. Prior to exercise participants consumed a high carbohydrate meal, with placebo or 5 mg/kg BM-1 caffeine. No significant performance effect was identified (p=0.099) despite a 12.8% (109 m) improvement in exercise capacity following caffeine. Rates of carbohydrate and fat oxidation did not differ between conditions and nor were differences apparent for plasma glucose, fatty acids, glycerol, β-hydroxybutyrate (p>0.05). However, an increase in lactate was observed for caffeine (p=0.039). A significant condition effect on rating of perceived exertion was identified (p<0.001), with the overall mean for the protocol lowered to 11.7±0.9 au for caffeine compared to 12.8±1.3 au. Caffeine supplementation with a carbohydrate feeding strategy failed to affect metabolic and metabolite responses, although reductions in perception of exercise were observed. While a 12.8% increase in exercise capacity was noted the findings were not significant, possibly due to the small sample size.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • 3-Hydroxybutyric Acid / blood
  • Athletic Performance / physiology*
  • Blood Glucose / metabolism
  • Caffeine / administration & dosage*
  • Diet, Carbohydrate Loading*
  • Dietary Carbohydrates / blood
  • Double-Blind Method
  • Energy Metabolism
  • Exercise / physiology*
  • Fatty Acids / blood
  • Glycerol / blood
  • Humans
  • Lactic Acid / blood
  • Male
  • Perception / physiology
  • Performance-Enhancing Substances / administration & dosage*
  • Physical Exertion / physiology
  • Soccer / physiology*
  • Young Adult

Substances

  • Blood Glucose
  • Dietary Carbohydrates
  • Fatty Acids
  • Performance-Enhancing Substances
  • Lactic Acid
  • Caffeine
  • Glycerol
  • 3-Hydroxybutyric Acid