Caffeine
Conditions
Brief summary
In previous research we have shown that an acute caffeine dose of 5 mg/kg body mass reduces heart rate at rest and during low intensity exercise, with the effect dissipating as exercise intensity increases. If, as suspected, the effect at rest and at low intensities is due to an effect of caffeine on parasympathetic activity, this is likely to be reflected in an increase in heart rate variability (the beat-to-beat fluctuation in heart rate). The aim of this study is therefore to investigate the effect of caffeine on heart rate and heart rate variability at rest and during submaximal exercise.
Interventions
DRUGCaffeine
Single pill in an acute dose of 5 mg per kg of body mass
DRUGPlacebo
Single pill in an acute dose of 5 mg per kg of body mass
Sponsors
St Mary's University College
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
MALE
Age
18 Years to 55 Years
Healthy volunteers
Yes
Inclusion criteria
* Trained cyclists
Exclusion criteria
* Injured or a contraindicative medical condition
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Heart rate variability | From baseline to completion, up to 31 days | Change from baseline in heart rate variability measured at rest and at five different exercise intensities (40, 50, 60, 70 and 80% percent of maximal oxygen uptake) on an electromagnetically-braked cycle ergometer |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Heart rate | From baseline to completion, up to 31 days | Change from baseline in heart rate measured at rest and at five different exercise intensities (40, 50, 60, 70 and 80% percent of maximal oxygen uptake) on an electromagnetically-braked cycle ergometer |
Outcome results
None listed