Postprandial glucose and insulin responses to a postexercise grain meal.

This study investigated the effect of exercise, performed one hour prior to a meal, on post-meal glucose and insulin responses in horses. The research found that moderate exercise before eating did not significantly change glucose or insulin responses, suggesting that an hour’s gap after light exercise suffices for normal glucose metabolism of a grain meal in horses.

Objective and Methodology of the Study

• The researchers aimed to explore the impact of exercise executed an hour before meal consumption on glucose and insulin responses in horses.
• This research involved the study of eight mature male horses (geldings) in a two-period crossover design experiment.
• In each period, four horses were subjected to different conditions. In one condition (NoEx), the horses received a meal after a 14-hour fast. In the other condition (PostEx), the horses did the same but also undertook a bout of exercise, comprising 48 minutes of walking and trotting.

Data Collection and Analysis

• Blood samples from the horses were taken before and every 30 minutes for five hours after the meal.
• The researchers measured glucose and insulin levels in these samples.
• They assessed the measurements statistically to determine any difference between the two sets of conditions (NoEx and PostEx).
• The team observed whether glucose and insulin concentrations differed at various time points before and after the meal, how fast they increased within 90 minutes after the meal, and total change in glucose and insulin levels (captured as area under the response curves).
• The glucose-to-insulin ratio was also compared between the two conditions.

Findings of the Study

• The study found that glucose and insulin concentrations were not significantly different at any of the measured points in time between the two treatments.
• Post-meal glucose and insulin levels increased at similar rates in both groups from 0 to 90 minutes.
• Peak glucose and insulin concentrations and the overall change (area under the curve) in glucose and insulin levels did not significantly vary between the two treatment groups.
• The glucose-to-insulin ratio was also not different between the two groups, before or after the meal.
• This suggested that a bout of mild work done an hour prior to a meal did not affect the glucose or insulin response to eating in horses.

Conclusion

• Based on this study’s findings, it appears an hour’s rest after a period of light exercise is adequate for horses to maintain normal glucose metabolism after a grain meal.