Killgore William D S, Kipman Maia, Schwab Zachary J, Tkachenko Olga, Preer Lily, Gogel Hannah, Bark John S, Mundy Elizabeth A, Olson Elizabeth A, Weber Mareen
aCenter for Depression, Anxiety, and Stress Research, McLean Hospital, Belmont bDepartment of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA.
Neuroreport. 2013 Dec 4;24(17):962-7. doi: 10.1097/WNR.0000000000000029.
Physical exercise has many health benefits, including improved cardiovascular fitness, lean muscle development, increased metabolism, and weight loss, as well as positive effects on brain functioning and cognition. Recent evidence suggests that regular physical exercise may also affect the responsiveness of reward regions of the brain to food stimuli. We examined whether the total number of minutes of self-reported weekly physical exercise was related to the responsiveness of appetite and food reward-related brain regions to visual presentations of high-calorie and low-calorie food images during functional MRI. Second, we examined whether such responses would correlate with self-reported food preferences. While undergoing scanning, 37 healthy adults (22 men) viewed images of high-calorie and low-calorie foods and provided desirability ratings for each food image. The correlation between exercise minutes per week and brain responses to the primary condition contrast (high-calorie>low-calorie) was evaluated within the amygdala, insula, and medial orbitofrontal cortex, brain regions previously implicated in responses to food images. Higher levels of exercise were significantly correlated with lower responsiveness within the medial orbitofrontal cortex and left insula to high-calorie foods. Furthermore, activation of these regions was positively correlated with preference ratings for high-calorie foods, particularly those with a savory flavor. These findings suggest that physical exercise may be associated with reduced activation in food-responsive reward regions, which are in turn associated with reduced preferences for unhealthy high-calorie foods. Physical exercise may confer secondary health benefits beyond its primary effects on cardiovascular fitness and energy expenditure.
体育锻炼对健康有诸多益处，包括改善心血管健康、促进瘦肌肉发育、提高新陈代谢、减轻体重，以及对大脑功能和认知产生积极影响。最近的证据表明，定期体育锻炼还可能影响大脑奖赏区域对食物刺激的反应性。我们研究了自我报告的每周体育锻炼总分钟数是否与功能性磁共振成像（fMRI）期间食欲和食物奖赏相关脑区对高热量和低热量食物图像视觉呈现的反应性有关。其次，我们研究了这种反应是否与自我报告的食物偏好相关。在接受扫描时，37名健康成年人（22名男性）观看了高热量和低热量食物的图像，并对每张食物图像给出了喜好程度评分。在杏仁核、脑岛和内侧眶额皮质（这些脑区先前被认为与对食物图像的反应有关）内，评估了每周锻炼分钟数与大脑对主要条件对比（高热量>低热量）的反应之间的相关性。较高水平的锻炼与内侧眶额皮质和左侧脑岛对高热量食物的较低反应性显著相关。此外，这些区域的激活与对高热量食物，特别是具有咸味的食物的偏好评分呈正相关。这些发现表明，体育锻炼可能与食物反应性奖赏区域的激活减少有关，而这反过来又与对不健康高热量食物的偏好降低有关。体育锻炼可能在其对心血管健康和能量消耗的主要影响之外带来额外的健康益处。
