The most used drug in the world is caffeine. In the world of sports, it comes in the form of pill, powder, or the almighty Starbucks cup. Research has been done to show the effects it has on athletic performance. There are plenty of positive attributes for caffeine, but it is not always a great idea. Depending on what is on the training plan caffeine may excel or inhibit training.
Caffeine decreases reaction time!
The literature for caffeine and reaction time is surprising as it points to a decrease in reaction time with caffeine. Reaction time is defined as the period of time it takes from stimulus to response. One study examined the effects of caffeine on simple reaction time and mood and noted a significant decrease in simple reaction time after the ingestion of caffeine compared to a placebo (Souissi et al, 2012). The theory behind it was that elevated levels of anxiety decreased simple reaction time. A separate study notes that caffeine had been shown in multiple previous studies to have a reduction on simple reaction time (Saville et al, 2018). This study assessed the reasoning behind the reduction and concluded that it was likely due to attentional versus motor processes. Perhaps what was even more interesting was how the variable of sleep impacted caffeine’s effect on reaction time.
Fatigued or well rested?
Souissi et al (2014) suggested that sleep deprivation may change the effect caffeine has on reaction time compared to a rested individual. The study showed that while caffeine continued to show reduced simple reaction time one hour after consumption of caffeine the opposite was true in sleep deprived participants. Results of participants showed increased reaction time after consuming caffeine when they were deprived of sleep for 36 hours. The reasoning behind the difference discovered was explained by caffeine possibly having an antagonistic effect on adenosine. This was thought to potentially cause an increase in dopamine and adrenaline which improves the attention level. In other words, if you are fatigued caffeine may have a more positive effect on reaction time.
So when is coffee time?
What practical knowledge can be gained from this? Consider what skills are being performed before ingesting too much caffeine. If the day’s tasks relay on reaction time, maybe playing a sport such as tennis do not overdo the caffeine. If the goal is endurance based, then caffeine will be beneficial. The explanations of how caffeine effects mood and attention levels did provide some clarity behind why caffeine would impact reaction time negatively. It also showed that there could be a place for the use of caffeine in sleep deprived athletes before performance. An example of this would be in mountaineering where lack of sleep is common and the need for peak performance is critical.
Take away:
- Caffeine decreases reaction time.
- Caffeine can increase endurance.
- Choose when to caffeinate based on requirements of sport being performed.
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References
Souissi, M., Abedelmalek, S., Chtourou, H., Atheymen, R., Hakim, A., & Sahnoun, Z. (2012). Effects of morning caffeine ingestion on mood states, simple reaction time, and short-term maximal performance on elite judoists. Asian Journal of Sports Medicine, 3(3), 161–167. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3445643/
Saville, C. W. N., de Morree, H. M., Dundon, N. M., Marcora, S. M., & Klein, C. (2018). Effects of caffeine on reaction time are mediated by attentional rather than motor processes. Psychopharmacology, 235(3), 749–759. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5847000/
Souissi, M., Chtourou, H., Abedelmalek, S., Ghozlane, I. B., & Sahnoun, Z. (2014). The effects of caffeine ingestion on the reaction time and short-term maximal performance after 36 h of sleep deprivation. Physiology & Behavior, 131, 1–6. https://doi.org/10.1016/j.physbeh.2014.04.012