What Determines Reaction Time and How to Improve It

Scientists examine the factors affecting reaction time and determine they are less neurological and more dependent on things we can actually train and improve.

Since reaction time is the length of time between a stimulus and a person’s response to it, we could say that reaction time is important for every sport. We normally think of a starting pistol for a race, and the shorter the race the more critical reaction time is. But even in a very different sort of sport, such as a combat sport, the athletes need to react to every punch.

When you think about reaction time you begin to wonder just how fast a person can react or if there are differences in reaction time between people. In a recent study in the Journal of Strength and Conditioning researchers tried to answer these questions.

Researchers looked at data from 1,319 sprinters running a 100-meter sprint. In such a short race, a difference in reaction time could make the difference between first and last, but the results may extend to any sport. The researchers looked at pretty much everything they could think of that might affect reaction time. So without further ado, let’s get to the results.


Height was one trait they examined. Since the foundation of reaction time is neurological, it stands to reason that a taller athlete might have slower reaction times because signals have further to travel down the nerves. However, this was not the case, probably because the speed at which the nerves work is simply too fast to register.


Psychological pressure has an important role. In general, reaction times got shorter the more important the race was. This might be neurological in nature – potentiation of the nerves from the excitement of the race. However, it could also be because runners kept some in the tank in earlier qualifying rounds, knowing the critical races were yet to come. The female athletes also had a small worsening of reaction time in the final, perhaps because the excitement was such that they worried about a false start.


With training, reaction time shortens. This might be because of better tactical preparation. More experienced athletes are better prepared for all of the queues for the start of a race, and so they react faster at the right time.


In general, reaction time decreases with age. That is to say, the older the athlete is the faster his or her reaction time. This is probably because of a combination of factors we’ve touched on, like more experience and more muscle. This might also be partially a selection bias, since older athletes still competing made it to that level because of being superior athletes, in part because of quicker reaction time. This improvement of reaction time plateaus when the athlete reaches his or her thirties.


Men have an average reaction time 100ths of a second faster than women. A faster reaction might be due to greater strength. Reaction time depends in part on force development, which is faster in stronger muscles. And unlike men, who get faster and faster reaction times up until their thirties, women continue to improve on into their thirties.

So, for those of us who aren’t competitive sprinters or coaches of sprinters, there is still much to take away. Reaction time in sprinters only had a weak correlation to performance, but it’s still an important one in many sports. It seems as though the two biggest contributors to reaction time are not neurological as we might think, but rather a product of both power and experience, and we can develop these for any sport.


1.Espen Tonnessen, et. al., “Reaction Time Aspects of Elite Sprinters in Athletic World Championships,” J Strength Cond Res 27(4), 2013

Photo courtesy of Shutterstock.

Leave a Comment