Exercise training bradycardia is largely explained by reduced intrinsic heart rate

Decreased maximal heart rate with aging is related to reduced -adrenergic responsiveness but is largely explained by a reduction in intrinsic heart rate

Christou DD, Seals DR. Decreased maximal heart rate with aging is related to reduced -adrenergic responsiveness but is largely explained by a reduction in intrinsic heart rate. J Appl Physiol 105: 24–29, 2008. First published May 15, 2008; doi:10.1152/japplphysiol.90401.2008.—A decrease in maximal exercise heart rate (HRmax) is a key contributor to reductions in aerobic exercise capacity with a...

Decreased maximal heart rate with aging is related to reduced {beta}-adrenergic responsiveness but is largely explained by a reduction in intrinsic heart rate.

A decrease in maximal exercise heart rate (HR(max)) is a key contributor to reductions in aerobic exercise capacity with aging. However, the mechanisms involved are incompletely understood. We sought to gain insight into the respective roles of intrinsic heart rate (HR(int)) and chronotropic beta-adrenergic responsiveness in the reductions in HR(max) with aging in healthy adults. HR(max) (Balke...

Point: Exercise training-induced bradycardia is caused by changes in intrinsic sinus node function.

in intrinsic sinus node function 5 6 7 Mark R. Boyett, Yanwen Wang, Shu Nakao, Jonathan Ariyaratnam, George Hart, 8 Oliver Monfredi and Alicia D’Souza 9 10 11 Cardiovascular Sciences, University of Manchester, UK 12 13 14 Corresponding author: Professor Mark Boyett, Cardiovascular Sciences, University of Manchester, 15 46 Grafton Street, Manchester M13 9NT, UK 16 Phone: +44-161-2751192 Email: m...

the respiratory exchange ratio is higher in older subjects, but is reduced by aerobic exercise training

Loss of resting bradycardia with detraining is associated with intrinsic heart rate changes.

The mechanisms underlying the loss of resting bradycardia with detraining were studied in rats. The relative contribution of autonomic and non-autonomic mechanisms was studied in 26 male Wistar rats (180-220 g) randomly assigned to four groups: sedentary (S, N = 6), trained (T, N = 8), detrained for 1 week (D1, N = 6), and detrained for 2 weeks (D2, N = 6). T, D1 and D2 were treadmill trained 5...