Before any race, you will no doubt see most runners engaged in stretching. They will either be sitting on the ground trying to touch their toes, or pulling their foot back to stretch the quads. These runners want to ensure that their muscles are ready to race. But what if pre-race stretching actually hurts performance?
In his excellent and informative book Holistic Strength Training for Triathlon, Andrew Johnston argues that static pre-race stretching will make a runner slower.
As researchers Nelson, Kokkonen, and Arrnall explain it, the stretching regimen placed a proportion of the motor units into a fatiguelike state prior to the initiation of the (event). Placing specific motor units into a fatiguelike state would decrease the pool of motor units available for activation, this loss of motor units from the pool of available moor units could hasten the fatigue and lead to a decrease in performance.
In other words, runners who engage in a complex pre-race routine of static stretching are actually fatiguing their muscles.
Johnston states that diligent stretching is important, but that it must be done after a workout or race, not before. Stretching well after a run helps to “re-set” the muscles to their ideal resting state. Failure to stretch after a race or workout will teach your muscles that their ideal resting state is the state they have been throughout the workout: short and tight.
While static stretching is not recommended before a run, it is perfectly fine to engage in dynamic stretching and drills to warm up the muscles before a run. Dynamic stretching involves constant movements that serve to wake up the body’s muscles, instead of making them fatigued. This will effectively warm you up for the race without causing a decrease in your performance.