Table 1 Summary of the effects of caffeine on performance
From: The effects of caffeine, nicotine, ethanol, and tetrahydrocannabinol on exercise performance
Caffeine | |||
|---|---|---|---|
WADA status: now being monitored (stimulants - in competition only), banned from 1962 to 1972 and again from 1984 to 2003 at urinary caffeine concentrations >12 μg/ml | |||
Acute effect | Effect on performance | Caffeine dose | Reference |
Greater reliance on fat metabolism; increased FFAs; lower respiratory exchange ratio (RER) | Increased time trial performance | 6 mg/kg body mass | Mc Naughton et al. [34] |
Counteract central fatigue, directed effect on the CNS | 3% PMAX increase, increase in voluntary activation, maintenance of MVC | 6 mg/kg body mass | Del Coso et al. [35] |
No clear mechanism; effect on CNS (greater motor unit recruitment and altered neurotransmitter function) or direct effect on skeletal muscle | Enhanced time trial performance | 6 mg/kg caffeine 1 h pre-exercise and ~1.5 mg/kg after 2 h of exercise | Cox et al. [33] |
No mechanism proposed | No significant effects observed on performance | 1.5 or 3 mg/kg body mass of caffeine 1 h before cycling | Desbrow et al. [65] |
Direct effect on skeletal muscle; interaction with ryanodine receptor; potentiated calcium release from the SR | Increase in contraction force at low frequency stimulation (20 Hz) | 6 mg/kg 100 min before stimulation | Tarnopolsky et al. [23] |
Blunted pain response | Significantly higher reps during leg press set 3 with caffeine, same RPE | 6 mg/kg 1 h prior to 10-RM bench and leg press | Green et al. [66] |
Glycogen-sparing effect & increased utilization of intramuscular TGs and plasma FFAs with caffeine | Increased cycling time trial performance with caffeine | 9 mg/kg body mass 1 h before exercise | Spriet et al. [13] |