OPTIMAL MANUAL CONTROL FOR HEART RATE TRACKING DURING TREADMILL EXERCISES

Recently, a nonlinear dynamic system has been presented to model the heart rate (HR) response during and after treadmill exercise. The parameters of the model can be estimated and individualized. Based on the nonlinear model, several control techniques for the regulation of HR during treadmill exercise have been proposed. But commercial treadmills may not have equipments to be computer-controlled. In this paper, an optimal manual method is presented to track a predefined HR trajectory. A piecewise constant speed profile is considered as the input to the system and computed by an optimization procedure offline. The objective function is constituted in term of heart rate deviation from its desired. The subject must change manually the speed of the treadmill according to the optimal protocol periodically. The time interval between two speed changes should be long enough so that the subject is able to change the speed. Also, the proposed method is such that, limited attention for control is needed and the controller is not always active.