This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Physiology
Which of the following is not increased during isometric exercise? 
Select and explain. 
A. Respiratory rate, B. Hea rate, C. Stroke volume, D. Total peripheral reisistance
D: Total peripheral reisistance
Answer: D: Total peripheral reisistance 
Explanation: Net fall in total peripheral resistance due to vasodilation in exercising musclesWith the sta of an isometric muscle contraction, the hea rate rises, probably as a result of psychic stimuli acting on the medulla oblongataWithin a few seconds of the onset of an isometric muscle contraction, systolic and diastolic blood pressures rise sharply.The response to exercise involving isotonic muscle contraction is similar in that there is a prompt increase in hea rate, but different in that a marked increase in stroke volume occursIncreased O2 consumption result in increase of respiratory rateRef: Ganong&;s review of medical physiology 23rd edition pg no: 518