Blood pressure and heart rate response to static exercise in relation to electromyographic activity and force development.

摘要: 5 healthy men performed static knee extension (90 degree angle) with one leg for min. In series of experiments the force was held constant at 20% isometric maximal voluntary contraction. other initial development also 20%, but smoothed, rectified electromyographic activity, (SREMG) recorded after s contraction kept constant. Heart rate (HR), arterial mean blood pressure (MBP) (measured 20 cm proximally to elbow in a. brachialis), EMG (surface electrodes) from lateral portion m. quadriceps femoris, and were continuously recorded. HR MBP increased approximately 40% force-constant SREMG-constant experiments. The greatest increase occurred during first two minutes SREMG doubled, most marked increases occurring very early late parts correlated both (r = 0.85) 0.98). declined quickly minute remained about 12% MVC thereafter. observed cardiovascular responses can best be explained as result combined action central peripheral drives, drive being related activity recruitment motor units, mediated through chemoreceptors exercising muscles.