Purpose
We investigate the effects of 12-week interval training of moderate- or high-intensity exercise on blood lipids and plasma levels of adiponectin.
Methods
Thirty-four obese adolescent females [age = 15.9 ± 0.3 years; BMI and BMI-Z-score = 30.8 ± 1.6 kg/m2 and 3 ± 0.3, respectively], were randomized to high-intensity interval training (HIIT, n = 11), moderate-intensity interval training (MIIT, n = 11), or a control group (CG, n = 12). Maximal oxygen uptake ( $$\mathop V\limits^{.} {\text{O}}_{{2{\text{peak}}}}$$ V . O 2 peak ), maximal aerobic speed (MAS), plasma lipids and adiponectin levels were measured in all subjects before and after training.
Results
Following the training program, in both training groups, body mass, BMI-Z-score, and percentage body fat (% BF) decreased, while $$\mathop V\limits^{.} {\text{O}}_{{2{\text{peak}}}}$$ V . O 2 peak and MAS increased. Low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and adiponectin levels were positively altered (−12.6 and −7.4 %; 6.3 and 8.0 %; 35.8 and 16.2 %; high to moderate training program, respectively). Waist circumference, triglyceride and total cholesterol decreased only in HIIT group (−3.5; −5.3 and −7.0 %, respectively, in all P < 0.05). Significant decrease in the usual index of insulin resistance (HOMA-IR) occurred in HIIT and MIIT groups (−29.2 ± 5.3 and −18.4 ± 8.6 %, respectively; P < 0.01).
Conclusion
The results show that HIIT positively changes blood lipids and adiponectin variables in obese adolescent girls, resulting in improved insulin sensitivity, as attested by a lower HOMA-IR, and achieving better results compared to moderate-intensity exercise.