The Impact of High Intensity Intermittent Exercise (HIIE) on Serum Leptin Levels in Sedentary Overweight Adult Women

The prevalence of a sedentary lifestyle is increasing, which can lead to overweight and subsequently obesity, potentially triggering metabolic diseases. The objective of this study is to analyse the HIIE impact on serum leptin levels in sedentary overweight adult women. Twenty-four adult women with a BMI falling within the overweight category (23-24.9 kg/m²) were selected as subjects of this study. They were randomly divided into two groups: the control and the HIIE group. The HIIE group underwent static cycling, and the session lasted a total of 25 minutes which consisted of a 3-minute warm-up, 20 minutes of core exercise, and a 2-minute cool-down. The core exercise of the HIIE protocol followed a 1:1 ratio, involving 10 sets of high intensity cycling (80-90% of HRmax) for 60 seconds, alternated with low intensity cycling at a lower speed of 40 rpm without load. Blood samples for serum leptin measurement were collected before (pre-data) and 1 hour after the completion of the HIIE session (post-data). The post-data leptin levels (ng/mL) in both the control and HIIE groups showed a significant decrease compared to the pre-data levels (p<0.05; Cpre=74.521±16.658 vs. Cpost=68.178±19.367; HIIEpre=57.749±19.327 vs. HIIEpost=48.010±17.508). Based on these results, the study concludes that HIIE led to a greater reduction in serum leptin levels. From a physiological perspective, leptin is essential for appetite suppression. In overweight individuals, leptin levels tend to increase. However, due to the occurrence of leptin resistance, its ability to reduce appetite is compromised. Therefore, further research is needed to investigate leptin sensitivity.