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VAN DIJK, J.-W., R.J.F. MANDERS, E. E. CANFORA, W. VAN MECHELEN, F. HARTGENS, C. D. A. STEHOUWER, and L. J. C. VAN LOON. Exercise and 24-hGlycemic Control: Equal Effects for All Type 2 Diabetes Patients? Med. Sci. Sports Exerc., Vol. 45, No. 4, pp. 628-635, 2013. Purpose: We assessed the effect of a single bout of moderate-intensity exercise on subsequent 24-h glycemic control in 60 type 2 diabetes patients. Moreover, we examined whether individual responses to exercise were related to subjects' baseline characteristics, including age, body mass index, diabetes duration, exercise performance, medication, and HbA(1c) content. Methods: Sixty type 2 diabetes patients (insulin-treated, n = 23) participated in a randomized crossover experiment. Patients were studied on two occasions for 3 d under strict dietary standardization but otherwise free-living conditions. Parameters of glycemic control (means [95% confidence interval]) were assessed by continuous glucose monitoring over the 24-h period after a single bout of moderate-intensity endurance-type exercise or no exercise at all (control). Results: Type 2 diabetes patients experienced hyperglycemia (blood glucose >10 mmol.L-1) for as much as 8:16 h:min (6:44 to 9:48 h:min) per day. The prevalence of hyperglycemia was reduced by 31% to 5: 38 h: min (3: 17 to 7: 00 h: min) over the 24-h period after the exercise bout (P

PURPOSE: High levels of cardiorespiratory fitness (.VO2max) are associated with reduced risk of cardiovascular morbidity and mortality. However, little is known to what extent longitudinal changes in .VO2max affect arterial wall thickness and stiffness, i.e., two major risk factors for cardiovascular disease. We therefore investigated the relationship between changes in .VO2max from adolescence (13-16 yr) to adulthood (age 36) and from young adulthood (21-32 yr) to age 36, and carotid intima-media thickness (IMT) and stiffness of the carotid, femoral, and brachial arteries, at age 36. METHODS: Analyses of changes in .VO2max from adolescence to age 36 consisted of 154 subjects (79 women), and from young adulthood to age 36 consisted of a subpopulation of 118 subjects (62 women). Throughout the years, .VO2max was measured directly with a maximal running test on a treadmill. When the subjects had the mean age of 36, carotid IMT and large artery stiffness (distensibility and compliance coefficients) were assessed noninvasively by ultrasound imaging methods. RESULTS: Longitudinal changes in .VO2max were not significantly associated with carotid IMT. Changes in .VO2max were inversely and significantly associated with large artery stiffness. These associations were not uniform throughout the arterial tree, being stronger and independent of changes in other risk factors in the muscular (brachial and femoral) arteries but dependent on and possibly mediated by concomitant changes in HDL cholesterol and body weight in the elastic carotid artery. CONCLUSION: Increases in .VO2max that occur from adolescence up to age 36 are associated with less arterial stiffness. Improving .VO2max by increasing physical activity levels may therefore contribute to a reduction in mortality from cardiovascular disease through decreasing arterial stiffness.