Effects of Diet Versus Exercise on Morphometric Measurements, Blood Hormone Concentrations, and Oral Sugar Test Response in Obese Horses.

This research explored the effects of dieting versus exercising in obese horses, demonstrating that both approaches led to comparable weight loss, albeit with some variations. The exercise group showed greater reduction in neck size and more significant improvement in insulin to glucose ratio.

Research Goals and Methodology

The aim of this study was to compare the effects of diet and exercise on obese horses. The research team implemented a diet or exercise protocol on ten obese horses that resulted in equal caloric restriction:

• The horses were grouped according to sex, age, and breed or breed type.
• One horse from each pair was assigned to either a diet plan, which restricted food intake to approximately 85% of digestible energy requirements, or an exercise routine, which resulted in the expenditure of around 15% of digestible energy requirements.
• This treatment continued for four weeks while measuring various indicators of their health and body condition.

Measurements and Results

To track the progress and effects of the applied methods, the researchers measured several factors weekly. These measurements included the horses’ body weight, heart girth, girth-to-height ratio, neck circumference, neck circumference-to-height ratio, belly girth, body condition score, cresty neck score, serum insulin, plasma leptin, and plasma ghrelin concentrations. An oral sugar test was also conducted at the beginning and end of the study period to measure the insulin to glucose ratio and the 60-minute insulin sensitivity index.

When assessing the results, both the diet and exercise groups showed similar decreases over time in most physical attributes including body weight, heart girth, girth-to-height ratio, belly girth, body condition score, and cresty neck score. There were, however, some differentiation in the results:

• The exercise group presented substantially larger decreases in neck circumference and neck circumference-to-height ratio.
• Additionally, the exercise group exhibited significant improvement in their log insulin-to-glucose ratio and showed a tendency for improvements in log insulin sensitivity index and plasma leptin concentrations.
• In contrast, the diet group did not show any changes in these areas.
• Overall, no changes were observed with regards to plasma ghrelin concentration in response to weight loss.