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Endurance exercise is usually prescribed with caution for hypertensive patients because of the possible adverse effects of increased blood pressure on cardiorespiratory function. Cardiopulmonary responses were studied in 11 young (37 +/- 4 years) and 10 elderly (65 +/- 4 years) male subjects during treadmill exercise with wrist weights (WW) and with no weights (NW) at constant 60% of their maximal heart rate for 8 min at each exercise condition. The results revealed that both groups had similar responses at rest. During maximal stress test, heart rate, oxygen consumption and minute ventilation were significantly (p less than 0.01) higher in the younger subjects. During 60% WW and NW exercises heart rate, oxygen consumption and minute ventilation were significantly (p less than 0.01) lower in the elderly than in the younger group. Diastolic and mean arterial blood pressures were significantly (p less than 0.01) higher in both groups during WW compared to NW exercise. However, minute ventilation and rate-perceived exertion were significantly (p less than 0.01) higher during NW compared to WW exercise. These measurements indicated a similar pattern of hemodynamics in younger and elderly hypertensive responders, with variable respiratory responses to endurance exercise. In addition, careful observation of blood pressure during exercise with WW is recommended for both groups where an increased afterload is contraindicated. We recommend the usage of controlled WW exercise for hypertensive responders of all age groups as part of their rehabilitative program.

Background: Aging-related changes occur mainly in the cardiopulmonary system and skeletal muscles, bringing about a reduction in physical performance. Consequently, maximal oxygen uptake (VO2max) decreases. Objectives: The current study investigated exercise oxygen utilization during maximal aerobic exercise in trained and untrained elderly. Methods: Fifteen trained (59.3 ± 1.1 years) and 15 untrained (60.1 ± 1.1 years) elderly underwent a peak cardiopulmonary exercise test on a bicycle ergometer. Arterial O2 was defined from echocardiograph and venous oxygen content. Results: At rest, trained compared to untrained elderly had significantly (p < 0.05) higher values of end diastolic volume (108.1 ± 5.8 and 100.7 ± 6.2 ml, respectively) and stroke volume (68.1 ± 4.3 and 57.3 ± 6.5 ml, respectively), while heart rate (68.7 ± 9.3 and 81.3 ± 8.2 beats · min–1, respectively), and mean arterial blood pressure (90.6 ± 6.9 and 95.4 ± 7.2 mm Hg, respectively) were significantly lower. At peak aerobic test, the trained elderly, compared to the untrained subjects, achieved significantly (p < 0.05) higher values of end diastolic volume (156.1 ± 8.2 and 134.1 ± 7.6 ml, respectively), stroke volume (123.0 ± 7.9 and 96.0 ± 4.8 ml, respectively), cardiac output (20.2 ± 1.5 and 15.0 ± 1.3 liters·min–1, respectively) and oxygen uptake (42.1 ± 2.1 and 31.1 ± 2.4 ml·kg–1·min–1, respectively), while diastolic blood pressure (70.3 ± 5.6 and 77.5 ± 4.2 mm Hg, respectively) and total peripheral resistance [4.3 ± 0.8 and 5.9 ± 1.41 (dyn·s–1·cm–5)·10–1, respectively], were significantly (p < 0.05) lower. Conclusions: The present study suggests that the differences between trained and untrained elderly in absolute oxygen uptake of the working muscles and peak power output at maximal exercise test are due to physical activity status. The higher aerobic capacity in the trained elderly is related to increased cardiovascular function and to a lesser extent to increased muscle mitochondria concentration and capillarity. Although untrained elderly have reduced maximal oxygen uptake at peak aerobic exercise, intrinsic regulation of mitochondrial function does not seem to be significantly altered because of aging associated physical inactivity. Therefore, untrained elderly can partially compensate for their lower cardiac output by increasing oxygen extraction to levels comparable with those of trained elderly.

Background: All-out anaerobic exercise may be dangerous for the older population, due to hypoxia and inappropriate blood pressure response. Objectives: This study compared and evaluated left ventricular function at peak all-out anaerobic effort in 12 well-trained older (58 ± 1 years) and 12 young men (22 ± 1 years). Methods: Subjects were studied by echocardiography at peak all-out anaerobic exercise, on a cycle ergometer. Results: Seven older subjects experienced ECG abnormalities. Significant (p < 0.05) differences between the older group and the young group, respectively, were noted for: cardiac output (9.8 ± 0.9 and 15.8 ± 0.9 l·min–1), left ventricular end-systolic pressure-volume ratio (4.7 ± 0.8 and 4.4 ± 4.9), left ventricular end-diastolic volume (104.8 ± 6.9 and 125.7 ± 6.2 ml), ejection fraction (67.1 ± 6.0 and 59.8 ± 5.5%), left ventricular end-systolic pressure volume ratio (4.4 ± 0.4 and 4.8 ± 0.3 ratio), and total peripheral resistance (966.0 ± 84.0 and 660 ± 82.8 dyn·s–1·cm–5). Conclusions: Data suggest that during all-out anaerobic exercise, forces opposing ejection were not reduced enough to avoid left ventricular dysfunction and ECG abnormalities in the older subjects. This is attributed to functional changes with age in the myocardium and associated blood vessels, leading to impairment of left ventricular function and blunted inotropic and chronotropic responses to catecholamine. Therefore, an all-out anaerobic-type effort should not be given to an older subject due to the great hazardous potential.

Cardiovascular responses were studied echocardiographically in 10 young (23 +/- 3 years) and 10 elderly (67 +/- 4 years) men, during upright isometric handgrip and deadlift. During handgrip and deadlift both groups showed significant increases in systolic and diastolic blood pressure. Those responses were significantly greater in both groups during deadlift. Heart rate was significantly higher in both groups during deadlift than resting and handgrip values. Oxygen uptake increased progressively and significantly across conditions, and was significantly higher for the younger subjects. Ejection fraction remained unchanged during handgrip in both groups. During deadlift it remained unchanged in the elderly while it increased significantly in the younger. Both groups increased significantly heart volumes from rest to handgrip. During deadlift end systolic volume was significantly lower from resting and handgrip values only in the young group. These data indicate a similar cardiovascular response to acute pressure overload in both groups.