Caffeine Can Reduce Pain During Exercise

A lot of people are drinking coffee, taking caffeine before a workout and they don't realize the actual benefit, they're experiencing less pain during the workout.

It's becoming increasingly common for athletes, before competing, to consume a variety of substances that include caffeine, motivated by the belief that it will help metabolize fat more efficiently.

Recearchers at the University Of Iceland have been investigating the relationship between caffeine and physical activity. The research work initially was focused on exploring possible links between caffeine intake, spinal reflexes and physical activity.

Earlier research determined caffeine works on the adenosine neuromodulatory system in the brain and spinal cord, and this system is heavily involved in nociception and pain processing. The theory developed that caffeine blocks adenosine from working, he speculated that it could reduce pain.

A number of studies support that conclusion, including investigations considering such variables as exercise intensity, dose of caffeine, anxiety sensitivity and gender.

The latest published study on the effects of caffeine on pain during exercise appears in the April edition of the International Journal of Sport Nutrition and Exercise Metabolism. The study examines the effects of caffeine on muscle pain during high-intensity exercise as a function of habitual caffeine use. Interestingly, caffeine consumed by individuals who rarely used it before and habitual users have the same amount of reduction in pain during exercise after consumption.

The study's 25 participants were fit, college-aged males divided into two distinct groups: subjects whose everyday caffeine consumption was extremely low to non-existent, and those with an average caffeine intake of about 400 milligrams a day, the equivalent of three to four cups of coffee.

After completing an initial exercise test in the lab on an ergometer, or stationary cycle, for determination of maximal oxygen consumption or aerobic power, subjects returned for two monitored high-intensity, 30-minute exercise sessions.

An hour prior to each session, cyclists who had been instructed not to consume caffeine during the prior 24-hour period were given a tablet. On one occasion, it contained a dose of caffeine measuring 5 milligrams per kilogram of body weight (equivalent to two to three cups of coffee); the other time, they received a placebo only.

During both exercise periods, subjects' perceptions of quadriceps muscle pain was recorded at regular intervals, along with data on oxygen consumption, heart rate and work rate.

If a person regularly consumes caffeine, they need more to have a bigger, mental-energy effect. But the tolerance effect is not ubiquitous across all stimuli. Even brain metabolism doesn't show this tolerance-type effect. That is, with individuals who are habitual users versus non-habitual users, if you give them caffeine and do brain imaging, the activation is identical.
In the future, further research might be able to determine caffeine's effect on sport performance. Although the current research has already shown that caffeine reduces pain reliably, consistently during cycling, across different intensities, across different people, different characteristics... The next logical question arises about whether the reduction in pain also translates into an improvement in sport performance. For now, the current research could prove encouraging for a range of people, including the average person who wants to become more physically active to realize the health benefits.

It's valuable as a practical application. If you go to the gym and you exercise and it hurts, you may be more likely to stop doing that because pain is an aversive stimulus that tells you to withdraw. Giving people caffeine and to reduce the amount of pain they're experiencing, would help them stick with the exercise. Maybe then they'll push a little harder as well and also better adapt to the exercise.

Center for Sport and Health Sciences, Iceland University of Education.