Caffeine has the ability to increase endurance during prolonged or short and low-intensity exercise. This study was aimed at assessing the effect of caffeine ingestion on short and high-intensity exercise, in moderately trained adults. The subjects were assessed thrice on different occasions, after intake of caffeine, placebo or nothing and were asked to perform the Wingate anaerobic test, a test that involves exercise against heavy resistance. It was found that the highest mechanical power exhibited by the subjects on performing the test was greater in those who ingested caffeine and placebo, as compared to the control group. It was concluded that the effects of caffeine were similar to those of the placebo.
Caffeine has been proven to be beneficial in terms of endurance, during prolonged exercise. However, the effects of caffeine during short-term, high-intensity exercises are ambiguous. A few studies have shown that caffeine is beneficial while others disprove the same. It has been suggested that caffeine could help in the attenuation of fatigue and that it might be able to alter the perception of exertion during exercises. High-intensity exercises are simulated by intense exercise against heavy resistance. Usually, mechanically braked bicycle ergometers are used in tests such as the Wingate test. This study was designed to assess the effects of caffeine on the performance of the Wingate test.
* The subjects included eight males and six females. They underwent the test on three separate occasions. They were given caffeine or placebo prior to two tests and nothing before the third test.
* The highest power achievable was calculated during each test. The average heart rates were also tabulated.
* The subjects were asked to rate the level of exertion based on a standard scale. Blood lactate levels were also determined after each test.
* The highest power achieved during the exercise interval was significantly higher in those who had consumed either caffeine or placebo, as compared to those who didn’t consume anything.
* The changes in heart rate were found to be insignificant in all the three conditions.
* The rating of the level of exertion post-exercise and the lactate levels were found to be greater in those who consumed placebo than in those who consumed caffeine.
Habitual caffeine intake could influence a person’s response to further intake. The study did not take measures to check caffeine consumption; it is possible that the results could have been influenced by the habits of the subjects. Hence, the authors suggest further research accounting for this bias by providing the subject with sufficient time prior to the commencement of the study.
Caffeine has been thought to lower the perception of exertion during prolonged and low-intensity exercises. However, the effects of caffeine during high intensity exercise were no different than those of placebo treatment. The average heart rate, peak power during exertion, lactate levels and an exertion-level assessment showed no favor toward those who had consumed a caffeinated drink. This study shows that mere placebo could play the role of caffeine, as shown in previous studies. Hence, to ascertain more details on caffeine, more studies need to be done comparing the effect of caffeine on exercises in trained and untrained populations, as also on habitual and non-habitual caffeine users.
For More Information:
Placebo Effects of Caffeine on Anaerobic Performance in Moderately Trained Adults
Publication Journal: Serbian Journal of Sports Sciences, September 2009
By Michael Duncan; University of Derby, England