The effect of long term moderate intensity exercise on heart rate and metabolic status in sedentary Labrador Retrievers.

Heart rate (HR) and oxygen uptake linearly increase during exercise, so the aim of this study was to investigate the effects of moderate exercise in sedentary dogs on heart rate frequency, as a marker of aerobic status. Fifteen Labrador Retrievers participated in a 4-month exercise protocol, and their body mass, serum biochemistry status and HR response were monitored and measured at the baseline and after 2 and 4 months of activity. The baseline control speed was set for each dog and corresponded to the moderate intensity mean HR value of 137.5 ± 2.58 beats per minute (BPM). During the experiment, the running speed was altered to maintain the baseline HR for each dog individually. The mean running speed needed to maintain the control HR increased significantly (P<0.01), measured after 2 and 4 months of aerobic exercise. Then mean HR at control speed after 2 and 4 months of moderate exercise decreased significantly (P<0.01) compared to the baseline value. Body mass decreased significantly after 2 months (P<0.01) and 4 months (P<0.05) compared to the baseline value.After 2 months of exercise albumin, creatinine and cholesterol concentrations significantly decreased, while alkaline phosphatase (ALP) activity significantly increased from the baseline values. After 4 months of exercise a statistically significant increase was found in glucose, triglycerides, and BUN concentrations from the baseline values. Compared to the 2 month results, BUN and albumin concentrations significantly decreased, while ALP activity significantly increased. This study demonstrated the positive effects of a long- term moderate intensity training protocol in sedentary dogs on heart rate and possibly also on aerobic capacity, as observed by the decrease in heart rate during exercise at the end of 4 months’ training.