A triathlete's stride is critical to his or her running performance. Some athletes have a stride that eases across the ground with grace and composure while others appear to strain with every step.
However, if each component of the running action is carefully analyzed and developed, even the most ungainly runners can find improvement.
The stride consists of two parts: the stance phase, where the leg is in contact with the ground, and the flight phase, where the leg moves through the air and prepares for contact with the ground and the next stride.
The stance phase: When a runner's foot hits the pavement, it is only in contact with the ground for about one-tenth of a second. In that short time, all of the mechanical forces that produce forward propulsion must be transferred through the leg. The powerful extension of the leg downward and backward creates the horizontal movement forward.
As Isaac Newton wrote in his laws of motion: for every action there is an equal and opposite reaction. So, the action of extending the leg backward creates a forward and upward movement (the flight phase).
The flight phase: As an athlete moves through the air, his leg swings backward and then moves rapidly forward. When the leading leg strikes, there can be a braking motion as speed is inhibited by the contact of the foot with the ground.
Athletes without efficient technique may be capable of generating substantial speed during the flight phase, but a jarring stance phase can hinder their forward progress. Overstriding is one of the key contributors to excessive braking during the stance phase.
Limb length, strength and running technique can affect stride length. Each athlete has an optimal stride length, so there is no one-size-fits-all rule; nonetheless, watch for excessive slapping of the feet on the pavement, and note that at most running speeds your right foot should strike the ground 21 times in 15 seconds.
Time yourself on your next run. If you are below 21 strikes for 15 seconds, you may be overstriding.
Doing it Right
Posture: Try to avoid exaggerated lean, either forward or back. Too much forward lean reduces the efficiency of the legs and can place strain on the hamstrings. Excessive backward lean can create muscular tension in the lower back and gluteal group, which can hasten fatigue and inhibit running efficiency.