Why getting off the ground quickly is important to improving running speed

Mar 10, 2023

Why, reacting to the ground, will improve your running speed?

Speed is described as the rate of change of position of an object in any direction, it is measured as the ratio of distance to the time in which the distance was covered. Ground contact time refers to the period of time between when the foot first makes contact with the ground (toe, mid-foot or heel) and the last part of the foot that leaves the ground. Ground contact time without other measures however do not mean much. The force generated with the ground contact time adds the other measure of flight time which is useful to know when looking to improve running speed.

Contact times and air times are similar to stride length and stride frequency. While knowing both measures is nice, the key is to know how these two variables influence horizontal speed. Whatever distance you are running/training for, understanding how long you spend on the ground and how quickly you can get off the ground are useful to know as you can plan your training programmes around this information. If your running style sees that you spend a lot more time on the ground your training sessions to improve speed should be lots of plyo metric training.

The more time you spend on the ground the more likely you are to sink into the ground on each stride, in effect this starts to decelerate your body. The reason the intervals, plyo and hill sessions will help you are that they work on your leg being a more dynamic part of your run. This allows your foot to be on and off the ground quicker, more effectively, the end result is that you will run quicker. Again this is the result of the wokr put in on your mobility, dynamic strength and technique to get to this end result, and that is before you start to work on your CV deveopment.

Ground contact time balance is the measure of how similar your left and right leg ground contact times are. GCT balance is normally displayed as a percentage split. A 50/50 split is the theoretical optimum and indicates an equal GCT for both legs. In reality, GCT balance is rarely 50/50. Anything between 49% and 51% is considered fairly symmetrical. However, if your GCT balance is beyond 49/51 (an imbalance of more than 2%) the asymmetry may affect your performance and put you at risk of injury.

The ways you can check for possible imbalances before you start training are;

  • How long can you stand on one leg with your eyes closed
  • Are you able to do a single leg squat on each leg
  • Complete the Foundation Running Assessment to see what your area for development needs to be

Typically, the faster you run, you’ll naturally spend more time suspended in the air, which is a result of generating enough power with every push-off. So, logically, by increasing the amount of time you spend in float, you’ll ultimately increase your speed. Surprisingly the most efficent place to be while running is in the air, so your aim is to spend as little time on the gorund as possible.

The more time you spend on the ground, the more friction you generate while running, and the more forces you have to slow down your forward motion. So, spending the least amount of time on the ground will go a long way in maintaining your speed. By increasing your hip range of motion, developing explosiveness, and improving your muscular activation, strength, and power, you will create performance boosts that transfer to an improved running economy and increased float time.

Building A Faster Runner