. Author manuscript; available in PMC: 2016 Jun 1.

Published in final edited form as: J Mol Cell Cardiol. 2015 Apr 11;83:1–13. doi: 10.1016/j.yjmcc.2015.04.005

Table 1.

Changes in cardiorespiratory reserve in healthy, community-dwelling persons during peak cycle exercise between the ages of 20 and 80 years (from Ref. 44)

Peak (A–V) O₂	(25%)	↓
Cardiac index	(25%)	↓
Heart rate	(25%)	↓
Stroke volume	No change
End diastolic volume	(30%)	↑
Peripheral vascular reserve	(30%)	↑
End diastolic volume	(275%)	↑
LV contractility	(60%)	↓
LV ejection fraction	(15%)	↓
Plasma catecholamines		↑
Cardiac and vascular response to		↓
beta-adrenergic stimulation