Longer rest intervals do not attenuate the superior effects of accumulated exercise on arterial stiffness.

PURPOSE: To examine and compare the acute effects of moderate-intensity continuous and accumulated exercise in three bouts with different intervals on arterial stiffness. METHOD: Nineteen healthy young males (mean age = 24.7 years) were randomized to no-exercise control (CON), continuous exercise (CE, 30-min cycling), accumulated exercise with 10-min intervals (AE10, 3 × 10-min cycling, 10-min interval), and accumulated exercise with 60-min intervals (AE60, 3 × 10-min cycling, 60-min interval) trial in balanced self-control crossover design. The intensity in all the exercise trials was set at 50% heart rate reserve. Cardio-ankle vascular index (CAVI), an index of arterial stiffness, was measured at baseline (BL), immediately after (0 min) and 60 min after the completion of the exercise. RESULTS: CAVI remained stable (6.8 ± 0.1, 6.8 ± 0.2, 6.9 ± 0.1 at BL, 0 and 60 min, respectively) in CON trial. Immediately after exercise, CAVI in CE, AE10 and AE60 trials all decreased significantly to similar degree compared to CON trial (P < 0.05 for CE, AE10 and AE60 vs. CON). Though CAVI in CE trial returned to baseline level after 60 min of recovery, CAVI in both AE10 and AE60 trials remained significantly low compared to CON trial (P < 0.01 for AE10 and AE60 vs. CON). CONCLUSION: When the total duration and relative intensity were matched, the effects of accumulated exercise in three bouts were superior to continuous exercise. Elongation of intervals between bouts did not attenuate the superior effects of accumulated exercise on arterial stiffness. TRIAL REGISTRATION: ChiCTR-OTRCC-14005229.

Grey-matter volume as a potential feature for the classification of Alzheimer's disease and mild cognitive impairment: an exploratory study.

Specific patterns of brain atrophy may be helpful in the diagnosis of Alzheimer's disease (AD). In the present study, we set out to evaluate the utility of grey-matter volume in the classification of AD and amnestic mild cognitive impairment (aMCI) compared to normal control (NC) individuals. Voxel-based morphometric analyses were performed on structural MRIs from 35 AD patients, 27 aMCI patients, and 27 NC participants. A two-sample two-tailed t-test was computed between the NC and AD groups to create a map of abnormal grey matter in AD. The brain areas with significant differences were extracted as regions of interest (ROIs), and the grey-matter volumes in the ROIs of the aMCI patients were included to evaluate the patterns of change across different disease severities. Next, correlation analyses between the grey-matter volumes in the ROIs and all clinical variables were performed in aMCI and AD patients to determine whether they varied with disease progression. The results revealed significantly decreased grey matter in the bilateral hippocampus/parahippocampus, the bilateral superior/middle temporal gyri, and the right precuneus in AD patients. The grey-matter volumes were positively correlated with clinical variables. Finally, we performed exploratory linear discriminative analyses to assess the classifying capacity of grey-matter volumes in the bilateral hippocampus and parahippocampus among AD, aMCI, and NC. Leave-one-out cross-validation analyses demonstrated that grey-matter volumes in hippocampus and parahippocampus accurately distinguished AD from NC. These findings indicate that grey-matter volumes are useful in the classification of AD.