I don’t know if the world of fitness professionals, academics, sports psychologists, etc… agree on a definition of agility in the field of sports and athletics. I briefly mentioned a few in my first blog post. But since the majority of subsequent posts will be on the subject of athletic agility, I thought I should go for a more complete definition. And since I don’t think the profession has a standard, agreed upon, definition, I’m going with what seems to be the most recent AND that makes good sense with me (it’s my blog, I’m allowed to do that!).
This definition comes from a pair of sports research scientists in Australia:
“a rapid whole-body movement with change of velocity or direction in response to a stimulus” (1)
Wow! So what does it mean? Let’s break it down. “Rapid whole-body movement”. “Rapid” means quick, got it. “Whole-body”. Interesting. One’s whole body is involved in getting the job done, not just the legs, torso, arms, feet, back, etc… but the whole body working in concert. This includes the brain, but we’ll get to that.
Let’s keep going. “Change of velocity or direction”. There is change involved: Change in speed means acceleration or deceleration: speeding up, slowing down rapidly. It can also mean a sudden change of direction, some evasive maneuver perhaps.
Now the really interesting part: “in response to a stimulus”. What does that mean? It means that something has to happen to cause you to change your movement. There’s a reason to zig, cut, sprint, etc… and the movement is executed in response to something that has happened around you. Can the reason (stimulus) be anything? No it can’t, according to the research scientists. It needs to be something you couldn’t have specifically rehearsed before hand. That is, you couldn’t have anticipated with 100% accuracy what the stimulus was going to be.
Let’s pretend we’re playing tennis. The stimulus (the thing we need to react to) is a shot coming our way. If we are lucky, we are in a ready position and not scrambling to get back into position. We don’t know before hand where the shot is going. However, experience tells us where it might go because we have been in this situation before, because we’ve played this person before, because our opponent’s body position limits the possibilities, etc… but we can’t know for certain. Then the shot comes. We need to quickly change direction (assuming the shot wasn’t right to us) and execute our own return strategy.
This scenario is one executed everyday by millions of people around the world and one that requires agility: A rapid change of direction or speed in response to a stimulus. And one other thing: we had to use our brains to assess the situation and make a decision. Our brains are involved.
If I was to change slightly the definition of agility presented above it would be as follows (and this is just my opinion):
“a rapid whole-body movement with change of speed or direction in response to a non-deterministic stimulus”
“Non-deterministic stimulus” is just a fancy way of saying that there are a range of possibilities for the thing we need to react to. [Aside: I used speed instead of velocity because, strictly speaking, velocity means the speed and direction of something, but never mind that.]
So now that we have a definition of agility, we can apply it to things to say what does and doesn’t involve agility. The research scientists that devised the definition of agility I’m discussing here used this example: The reaction of a sprinter to a starters pistol, while an important task that needs to be trained, it is not a task requiring agility. Why? Because the sprinter knows exactly what is required when the pistol goes off.
By contrast, a soccer player who quickly changes his speed or direction in order to evade an attacking player(s) is engaging in movement requiring agility because there is uncertainty in the stimulus (where and when the attack will come from) and a quick decision required as to what the response (movement) will be.
I’ll end this post with a couple more definitions. A skill that can be pre-planned (rehearsed) and/or does not involve a response to a stimulus is called a closed skill. On the other hand, open skills require a reaction to some uncertain range of events in the athletes environment.
References for this Post:
- Sheppard, J.M and Young, W.B, Agility Literature Review: Classifications, Training and Testing, Journal of Sports Sciences 2006, 24(9), pp 919-932.