Effect of endurance training on cardiac morphology in Alaskan sled dogs.

摘要: The cardiac morphology of 77 conscious Alaskan sled dogs before and after 5 mo endurance training (20 km/day team pulling a musher) was studied using two-dimensional M-mode echocardiography. Subgroups included with at least one season previous ("veterans") undergoing their first ("rookies"). Training resulted in significant (P < 0.05) decrease resting heart rate (-15%) increases interventricular septal thickness (systole, 15%; diastole, 13%), left ventricular (LV) internal dimension diastole (LVIDd, 4%), LV free wall systole (9%) (LVWd, 9%), atrial diameter (5%) all dogs, but the increase LVWd greater rookies (16%) than veterans (7%). increased end-diastolic volume index (8%), mass (24%), weight (24%) decreased LVIDd-to-LVWd ratio (-6%) did not alter index. We conclude that attributable to dilation hypertrophy is associated dogs. Disproportionate thickening accompanying suggests morphological changes are due pressure loading. These training-induced similar those documented human athletes combined isometric isotonic differ from studies trained on treadmills.