Blood pressure and heart rate response to voluntary and nonvoluntary static exercise in man.

6 healthy men produced static knee extension with one leg for 5 min. In one series of experiments the force was held constant at 20% of the isometric maximum voluntary contraction force. In another series of experiments the same subjects performed the same work non-voluntarily by direct percutaneous electrical stimulation. Heart rate and blood pressure was continuously recorded. Heart rate increased by 40% and systolic and diastolic blood pressure by 30% and 50% in both kind of experiments. It is concluded that receptors within the muscle has the full capacity to adjust central circulation to the muscle work performed.