Physiological changes

Blood pressure

• systolic increases, diastolic decreases
• leads to increased pulse pressure
• in healthy young people the increase in MABP is only slight

Cardiac output

• increase in cardiac output may be 3-5 fold
• results from venous constriction, vasodilation and increased myocardial contractibility, as well as from the maintenance of right atrial pressure by an increase in venous return
• heart rate up to 3-fold increase
• stroke volume up to 1.5-fold increase

Systemic vascular resistance falls in exercise due to vasodilatation in active skeletal muscles.