All are true about circulating changes in exercising muscle EXCEPT?
Ans. D Peripheral resistance increasesRef: Ganongy 25th ed. pg. 549* Blood flow of resting skeletal muscle is low (2-4 ml/100 gm/min)* When the muscle contracts, it compresses the vessels and when it develops 70% of its maximal tension, blood is completely interrupted.* Between contractions the flow is increased by 30 times* This is due to dilatation of arterioles and precapillary sphincters cause of 10-100 times increase in open capillaries* During exercise there is a net fall in peripheral resistance, due to vasodilation in exercising muscles. Hence the SBP increases moderately and diastolic pressure remains unchanged or falls.
Complete flow stops on maximal tension reaching 70%
Blood supply increases by 30 times between contractions
Dilation of arterioles and pre-capillaries
Peripheral resistance increases
Heart, Circulation, and Blood