View Full Version : Analyzing running performance with the spring-mass model.

08-06-2008, 09:25 AM
Hello Colleagues,

Is anyone else using the spring-mass model to understand their running

I modified my home treadmill (1) to capture my step-frequency and

>From my running-in-place step-frequency I can calculate my leg-stiffness.
When I use this value in the model, its output (2) closely follows the
step-frequency and duty-factor I measure over the speed range (3).

I am especially interested in the mass specific power (watts/kg) expenditure
due to spring compression (4). The values shown in the PowerSpring/mass
curve (2 to 4.5 watts/kg) are close to the power expended by a mid-pack cyclist.

Does anyone else use the spring mass model in this way?

Ted Andresen
Math Department
St. Petersburg College
St. Petersburg, Florida

(1) A graph of the data from the model is at:

(2) A graph of the data from the model is at:

(3) The output tabulation from the model is at:

(4) How the model calculates the mass specific power:

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