The effect of interval versus continuous exercise on plasma leptin and ghrelin concentration in young trotters.

This study examines the impact of different types of exercise – interval and continuous – on the levels of leptin and ghrelin, two hormones linked to appetite and energy expenditure, in young Standardbred horses. The researchers found that continuous exercise increased leptin levels and ghrelin concentration, while interval exercise did not impact leptin levels but significantly reduced ghrelin concentration.

Research Methodology

• The research was carried out on 27 Standardbred horses aged between 2 and 3 years.
• These horses were split into two groups based on the type of exercise they performed: interval exercise and continuous exercise.
• Blood samples were taken from the horses at rest, immediately following exercise, and 30 minutes after the completion of the exercise.
• The concentrations of leptin and ghrelin in the plasma were measured using radioimmunoassay (RIA) tests.

Results

• Continuous exercise led to an increase in plasma leptin concentration whereas interval exercise did not affect the hormone level.
• The plasma ghrelin concentration measured after continuous exercise displayed a significant increase. In contrast, ghrelin concentration measured after interval exercise showed a significant decrease.
• An inverse correlation was found between the changes in plasma ghrelin concentration measured after the end of exercise and blood lactic acid concentration.

Conclusion

• The study’s findings highlight that medium-intensity exercise, such as trotting, whether in an interval or continuous format, has little effect on plasma leptin levels but significantly impacts plasma ghrelin concentration in young Standardbred horses.
• These changes in hormone levels could potentially influence the horses’ response to appetite and energy expenditure, although the research does not directly address this question.