Runners Gait analysis is one of the key things we do at SBR Sport. There have been a number of books written of late that describe how to run. The running motion or, runners gait has become a hot topic. For further information on this subject I would recommend Chi Running by Danny Dreyer
Herewith is a study on the running gait.
The major difference between running and walking is that in walking you have at least one foot on the ground. In running there are moments when both feet are off the ground.
Let’s split the gait up into its different phases:
Stance phase – the moment the front foot makes contact with the ground.
Swing phase – the leg moves backward, thus propelling the runner forward.
Takeoff – the foot now pushes off the ground and the runner is airborne.
Forward swing – the leg now returns through the air so that it can make contact with the ground once again.
A detailed look at each phase.
The stance phase:
As the foot plants on the ground a number of things occur, the Quadriceps flex in order to begin to absorb the shock of the runners body moving downward and his/her feet meeting with the ground. The main muscle used at this point is the Rectus Femoris. At impact the entire leg comes into play in order to dissipate shock.
The Subtalar joint now inverts allowing a degree of pronation (or inward roll of the heel) to take place. This is part of the body’s ability to absorb shock. A number of variances can take place at this point:
The foot can under pronate. This is also called Supination. This lack of foot roll hinders the legs ability to absorb shock. The resultant shock wave can lead to chronically tight Achilles Tendons, tight Calf muscles, anterior calf strain, Illiotibial Band syndrome and Lateral Knee pain.
The foot can over pronate. This is generally referred to as Pronation. This ‘over roll’ of the foot can lead to Tibia pain, Shin Splints, Anterior Calf strain and Medial or inside knee pain due to the rotation of the Tibia.
At SBR Sport we place runners on a treadmill and measure the degree of pronation. We only correct excessive pronation after 3 degrees. Anything less than this is part of the foot’s normal shock reflex.
It is alarming to see how many Running Shops misjudge this critical measurement and sell runners the wrong running shoes.
The Swing Phase
At this point the leg now begins to swing backwards. The hip flexors, hamstrings, quadriceps and cal f muscles power the leg backwards in order to move the runner forward. Whilst this happens, the arms are used to counterbalance the runner. As the left leg moves backward, the left arm moves forward.
The Takeoff Phase.
The Calf muscles now contract together with the hamstring muscles, thus propelling the runner forward and upward into the airborne moment of the cycle.
The Swing Phase.
The rear leg now begins to swing forward. The forward motion requires the hamstrings to contract giving the foot necessary clearance off the ground. The Psoas and Illium muscles also contract swinging the leg forward.
Muscle strength imbalances can play a major role at this point in causing injury. This is where Biokinetisists come into the equation. As an example, when the rear leg comes forward, the quads pull the lower leg forward, the hamstrings act as a control of this motion. An imbalance in muscle strength can cause injury.
At SBR Sport we look at a number of factors as we video runners on the treadmill.
We look at the moment of heel strike and the resultant pronation or lack thereof. We look at the ability of the hip flexors to stabilize the hip, forward lean of the runner and at how the foot lands.
This study has proved invaluable to a number of runners as they learn more about their running style.
This is a really complex field of study. I have done my best to simplify the topic for the purpose of the blog.
I know of few things more liberating than running. I wish you a wonderful run tomorrow.