Although the
effect of caffeine on endurance performance is well documented, a recent study
by researchers from South Africa investigated the possible
mechanisms why. The researchers studied the effect of caffeine in two
triathlons held two weeks apart. The study was conducted with male
and female triathletes who trained an average of 12.8 hours per week. The
triathletes consumed caffeine 60 minutes before their triathlon and time
to completion data was measured.
On average, caffeine supplementation reduced swim times by
3.7% and reduced overall times by 1.7 %. Males appeared to have better
performance effects from caffeine than females. What makes the study
quite interesting is the possible mechanism by which caffeine
acts. The ratings of perceived exertion (RPE) did not change.
However the improved performance suggested that caffeine had a central
effect resulting in greater muscle performance at the same perceived level
of exertion.
Higher levels of cortisol seen post exercise and higher peak
lactate levels also suggested that caffeine helps you work harder at
the same level of perceived exertion. In other words the mental effect of
caffeine on endurance performance is an important mechanism of action.
Posted by Dr. Robert Portman on 4/11/2019 to
Performance Tip Of The Week