This study compared the effects of self-selected exercise intensity (SEI) versus predetermined exercise intensity (PEI) on blood pressure (BP) and arterial stiffness in adolescents with obesity. A total of 37 adolescents, 14.7 (1.6) years old, body mass index ≥95th percentile were randomly allocated into SEI (n = 18; 12 boys) or PEI (n = 19; 13 boys). Both groups exercised for 35 minutes on a treadmill, 3 times per week, for 12 weeks. The SEI could set the speed at the beginning of the sessions and make changes every 5 minutes. The PEI adolescents were trained at an intensity set at 60% to 70% of heart rate reserve. Brachial and central BP, pulse pressure, augmentation index, and carotid–femoral pulse wave were determined at baseline and after 12 weeks. Both groups reduced brachial systolic BP (SEI, Δ = −9 mm Hg; PEI, Δ = −4 mm Hg; P < .01), central systolic BP (SEI, Δ = −4 mm Hg; PEI, Δ = −4 mm Hg; P = .01), and central pulse pressure (SEI, Δ = −4 mm Hg; PEI, Δ = −3 mm Hg; P = .02) without differences between groups. No changes in the augmentation index and carotid–femoral pulse wave were observed in either group. The SEI induced similar changes in various cardiovascular outcomes compared with PEI in adolescents with obesity.
Effect of Low- Versus High-Intensity Exercise Training on Biomarkers of Inflammation and Endothelial Dysfunction in Adolescents With Obesity: A 6-Month Randomized Exercise Intervention Study
Purpose: To investigate the effects of a low- versus high-intensity aerobic training on biomarkers of inflammation and endothelial dysfunction in adolescents with obesity. Methods: Sixty-two adolescents with obesity [age = 15 (14) y, body mass index = 34.87 (4.22) kg·m−2] were randomized to receive either a high-intensity training (HIT, n = 31) or a low-intensity training (LIT, n = 31) for 24 weeks. All participants also received nutritional, psychological, and clinical counseling. Leptin, total and subtype leukocyte counts, tumor necrosis factor-alpha, interleukin-6, myeloperoxidase, soluble intercellular adhesion molecule-1, and soluble vascular cell adhesion molecule-1 were obtained at baseline and after 24 weeks. Results: HIT reduced neutrophils [from 4.4 (1.9) to 3.6 (1.3) µL−1 × 103; P = .01] and monocytes [from 7.2 (2.5) to 5.2 (1.8) µL−1 × 102; P < .01], but LIT increased neutrophils [from 4.5 (1.7) to 5.2 (3.3) µL−1 × 103; P = .01]. Although tumor necrosis factor-alpha increased in LIT [from 13.3 (7.5) to 17.7 (10.8) pg·mL−1; P = .01], it decreased in HIT [from 12.4 (7.5) to 11.3 (6.2) pg·mL−1; P = .01]. No changes in leukocyte counts, soluble intercellular adhesion molecule-1, soluble vascular cell adhesion molecule-1, and homeostasis assessment model for insulin resistance were observed. Conclusions: Both HIT and LIT improved the inflammatory profile. The study, however, indicated that the number of biomarkers and the magnitude of changes were higher in the HIT compared with LIT.