Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital, Dallas, TX, USA.
Neuroimage. 2013 Nov 15;82:510-6. doi: 10.1016/j.neuroimage.2013.06.011. Epub 2013 Jun 12.
White matter (WM) integrity declines with normal aging. Physical activity may attenuate age-related WM integrity changes and improve cognitive function. This study examined brain WM integrity in Masters athletes who have engaged in life-long aerobic exercise training. We tested the hypothesis that life-long aerobic training is associated with improved brain WM integrity in older adults.
Ten Masters athletes (3 females, age=72.2 ± 5.3 years, endurance training >15 years) and 10 sedentary older adults similar in age and educational level (2 females, age=74.5 ± 4.3 years) participated. MRI fluid-attenuated-inversion-recovery (FLAIR) images were acquired to assess white matter hyperintensities (WMH) volume. Diffusion tensor imaging (DTI) was performed to evaluate the WM microstructural integrity with a DTI-derived metric, fractional anisotropy (FA) and mean diffusivity (MD).
After normalization to whole-brain volume, Masters athletes showed an 83% reduction in deep WMH volume relative to their sedentary counterparts (0.05 ± 0.05% vs. 0.29 ± 0.29%, p<0.05). In addition, we found an inverse relationship between aerobic fitness (VO2max) and deep WMH volume (r=-0.78, p<0.001). Using TBSS, Masters athletes showed higher FA values in the right superior corona radiata (SCR), both sides of superior longitudinal fasciculus (SLF), right inferior fronto-occipital fasciculus (IFO), and left inferior longitudinal fasciculus (ILF). In addition, Masters athletes also showed lower MD values in the left posterior thalamic radiation (PTR) and left cingulum hippocampus.
These findings suggest that life-long exercise is associated with reduced WMH and may preserve WM fiber microstructural integrity related to motor control and coordination in older adults.
随着正常衰老，脑白质（WM）完整性下降。身体活动可能会减弱与年龄相关的 WM 完整性变化并改善认知功能。本研究检测了终身有氧训练的大师运动员的脑 WM 完整性。我们检验了这样一个假设，即终身有氧训练与老年人脑 WM 完整性的提高有关。
10 名大师运动员（3 名女性，年龄=72.2±5.3 岁，耐力训练>15 年）和 10 名年龄和教育程度相似的久坐不动的老年人（2 名女性，年龄=74.5±4.3 岁）参与了本研究。采集磁共振成像液体衰减反转恢复（FLAIR）图像以评估脑白质高信号（WMH）体积。进行弥散张量成像（DTI）以评估 WM 微观结构完整性，用 DTI 衍生的指标，各向异性分数（FA）和平均弥散度（MD）来评估。
相对于久坐不动的对照组，大师运动员的深部 WMH 体积减少了 83%（0.05±0.05%对 0.29±0.29%，p<0.05），经全脑体积归一化后。此外，我们发现有氧运动能力（VO2max）与深部 WMH 体积之间呈负相关（r=-0.78，p<0.001）。使用 TBSS，大师运动员右侧上额状回（SCR）、双侧上纵束（SLF）、右侧下额枕束（IFO）和左侧下纵束（ILF）的 FA 值更高。此外，大师运动员左侧丘脑后辐射（PTR）和左侧扣带回海马的 MD 值也更低。
这些发现表明，终身锻炼与 WMH 减少有关，并且可能与老年人运动控制和协调相关的 WM 纤维微观结构完整性有关。
