We hypothesized that high-intensity interval training (HIIT) would be more effective than moderate-intensity continuous training (MICT) at improving endothelial function and maximum oxygen uptake (V̇o2 max) in obese adults. Eighteen participants [35.1 ± 8.1 (SD) yr; body mass index = 36.0 ± 5.0 kg/m(2)] were randomized to 8 wk (3 sessions/wk) of either HIIT [10 × 1 min, 90-95% maximum heart rate (HRmax), 1-min active recovery] or MICT (30 min, 70-75% HRmax). Brachial artery flow-mediated dilation (FMD) increased after HIIT (5.13 ± 2.80% vs. 8.98 ± 2.86%, P = 0.02) but not after MICT (5.23 ± 2.82% vs. 3.05 ± 2.76%, P = 0.16). Resting artery diameter increased after MICT (3.68 ± 0.58 mm vs. 3.86 ± 0.58 mm, P = 0.02) but not after HIIT (4.04 ± 0.70 mm vs. 4.09 ± 0.70 mm; P = 0.63). There was a significant (P = 0.02) group × time interaction in low flow-mediated constriction (L-FMC) between MICT (0.63 ± 2.00% vs. -2.79 ± 3.20%; P = 0.03) and HIIT (-1.04 ± 4.09% vs. 1.74 ± 3.46%; P = 0.29). V̇o2 max increased (P < 0.01) similarly after HIIT (2.19 ± 0.65 l/min vs. 2.64 ± 0.88 l/min) and MICT (2.24 ± 0.48 l/min vs. 2.55 ± 0.61 l/min). Biomarkers of cardiovascular risk and endothelial function were unchanged. HIIT and MICT produced different vascular adaptations in obese adults, with HIIT improving FMD and MICT increasing resting artery diameter and enhancing L-FMC. HIIT required 27.5% less total exercise time and ∼25% less energy expenditure than MICT.

Background/Objectives Inflammation, oxidative stress, and dysregulation of adipokines are thought to be pathophysiological mechanisms linking obesity to the development of insulin resistance and atherosclerosis. In adults, bariatric surgery reduces inflammation and oxidative stress, and beneficially changes levels of several adipokines, but little is known about post-surgical changes among adolescents. Subjects/Methods In two separate longitudinal cohorts we evaluated change from baseline of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), monocyte chemo-attractant protein-1 (MCP-1), oxidized LDL cholesterol (oxLDL), adiponectin, leptin, and resistin up to 12 months following elective laparoscopic roux en Y gastric bypass (RYGB) or vertical sleeve gastrectomy (VSG) surgery in adolescents with severe obesity. Results In cohort 1, which consisted of 39 adolescents (mean age 16.5±1.6; 29 females) undergoing either RYGB or VSG, IL-6 (baseline: 2.3±3.4 pg/mL vs. 12 months: 0.8±0.6 pg/mL, p<0.01), leptin (baseline: 178±224 ng/mL vs. 12 months: 41.4±31.9 ng/mL, p<0.001), and oxLDL (baseline: 41.6±11.6 U/L vs. 12 months: 35.5±11.1 U/L, p=0.001) significantly decreased and adiponectin significantly increased (baseline: 5.4±2.4 μg/mL vs. 12 months: 13.5±8.9 μg/mL, p<0.001). In cohort 2, which consisted of 13 adolescents (mean age 16.5±1.6 years; 10 females) undergoing RYGB, results were similar: IL-6 (baseline: 1.7±0.9 pg/mL vs. 12 months: 0.4±0.9 pg/mL, p<0.05) and leptin (baseline: 92.9±31.3 ng/mL vs. 12 months: 37.3±33.4 ng/mL, p<0.001) significantly decreased and adiponectin significantly increased (baseline: 6.1±2.9 μg/mL vs. 12 months: 15.4±8.0 μg/mL, p<0.001). When the cohorts were combined to evaluate changes at 12 months, oxLDL also significantly decreased (baseline: 39.8±16.7 U/L vs. 12 months: 32.7±11.9 U/L, p=0.03). Conclusions Bariatric surgery produced robust improvements in markers of inflammation, oxidative stress, and several adipokines among adolescents with severe obesity, suggesting potential reductions in risk for type 2 diabetes and cardiovascular disease.

Background The normal rate of subclinical vascular aging from adolescence to young adulthood has not been well‐characterized. We conducted a 5‐year longitudinal study among adolescents with normal‐weight, obesity, and/or type 2 diabetes mellitus to examine trajectories of early vascular aging. Methods and Results Adolescents (mean [SD] age 17.6 [3.5]; 35.3% male) had either normal weight (n=141), obesity (n=156), or type 2 diabetes mellitus (n=151) at baseline. Primary metrics used for early vascular aging included measures of vascular structure (carotid intima‐media thickness [cIMT]; common, internal, and bulb) and arterial stiffness (carotid‐femoral pulse wave velocity, and augmentation index). Longitudinal (5‐year) outcomes were examined using generalized estimating equations adjusting for baseline value, sex, race, and age. Compared with participants with normal weight, those with obesity had greater positive change in common cIMT (0.05 mm [0.03, 0.06]; P <0.001), bulb cIMT (0.02 mm [0.00, 0.05]; P =0.033), internal cIMT (0.03 mm [0.01, 0.05]; P <0.001), and pulse wave velocity carotid‐femoral (0.38 m/sec [0.14, 0.61]; P =0.001), and those with type 2 diabetes mellitus had greater positive change in common cIMT (0.05 mm [0.04, 0.07]; P <0.001), bulb cIMT (0.06 mm [0.04, 0.09]; P <0.001), internal cIMT (0.04 mm [0.02, 0.07]; P <0.001), augmentation index (4.67% [2.20, 7.13]; P <0.001), and pulse wave velocity carotid‐femoral (0.74 m/sec [0.46, 1.02]; P <0.001). Higher baseline systolic blood pressure was associated with greater positive change in common cIMT (0.007 mm [0.003, 0.011]; P <0.001), bulb cIMT (0.009 mm [0.002, 0.016]; P =0.01), internal cIMT (0.008 mm [0.003, 0.013]; P =0.001), and pulse wave velocity carotid‐femoral (0.066 m/sec [0.002, 0.130]; P =0.042). Conclusions These longitudinal data support the hypothesis that the presence of obesity, type 2 diabetes mellitus, and elevated baseline systolic blood pressure in early life accelerates the progression of risk factors key in the development of early vascular aging.