Exercise capacity in young and old mares.

摘要: OBJECTIVE To test the hypothesis that, compared with unfit young horses, older horses have lower aerobic capacity and reduction in other indices of exercise capacity. ANIMALS 6 (mean +/- SEM, 5.3 0.8 years 445 13 kg) aged (22.0 0.4 473 18 healthy Standardbred Thoroughbred mares. PROCEDURES The mares, accustomed to running on a treadmill, were tested by use an incremental test. None mares had received training for at least 4 months prior study. During testing, ran up fixed 6% grade, starting speed m/s, 1 m/s increase every 60 seconds (omitting 5 m/s) until they reached fatigue. Maximal oxygen uptake (VO2max) was measured open-flow calorimeter. Venous blood samples (10 ml) collected during last 10 each step used measure lactate concentration PCV. Calculated performance included velocity VO2max, maximal velocity, mmol/L; work rate (watts) those velocities also determined. RESULTS There differences (P < 0.05) between old run attained (8.7 0.5 versus 10.8 respectively), VO2max (89.4 4.3 117.3 9.5 ml/kg body weight/min, (8.0 9.8 0.7 respectively). Also, required reach mmol/L (7.5 m/s), (10.2 CONCLUSION Older substantially (-24%) than do CLINICAL RELEVANCE Many participate athletic activities into their late teens some so beyond age 20 years; thus, need exists explore ways adjust programs horses.