Aging Research Center (ARC), Department of Neurobiology, Care Sciences and Society (NVS), Karolinska Institutet, Tomtebodavägen 18A, 171 65 Stockholm, Sweden.
Aging Research Center (ARC), Department of Neurobiology, Care Sciences and Society (NVS), Karolinska Institutet, Tomtebodavägen 18A, 171 65 Stockholm, Sweden; The Swedish School of Sport and Health Sciences, Stockholm, Sweden.
Neuroimage. 2021 Jan 15;225:117500. doi: 10.1016/j.neuroimage.2020.117500. Epub 2020 Oct 24.
Regular physical activity is beneficial for cognitive performance in older age. A single bout of aerobic physical exercise can transiently improve cognitive performance. Researchers have advanced improvements in cerebral circulation as a mediator of long-term effects of aerobic physical exercise on cognition, but the immediate effects of exercise on cognition and cerebral perfusion are not well characterized and the effects in older adults are largely unknown.
Forty-nine older adults were randomized to a 30-min aerobic exercise at moderate intensity or relaxation. Groups were matched on age and cardiovascular fitness (VO2 max). Average Grey Matter Blood Flow (GMBF), measured by a pulsed arterial-spin labeling (pASL) magnetic resonance imaging (MRI) acquisition, and working memory performance, measured by figurative n-back tasks with increasing loads were assessed before and 7 min after exercising/resting.
Accuracy on the n-back task increased from before to after exercising/resting regardless of the type of activity. GMBF decreased after exercise, relative to the control (resting) group. In the exercise group, higher n-back performance after exercise was associated with lower GMBF in the right hippocampus, left medial frontal cortex and right orbitofrontal cortex, and higher cardiovascular fitness was associated with lower GMBF.
The decrease of GMBF reported in younger adults shortly after exercise also occurs in older adults and relates to cardiovascular fitness, potentially supporting the link between cardiovascular fitness and cerebrovascular reactivity in older age.
有规律的身体活动有益于老年人的认知表现。单次有氧运动可以短暂地提高认知表现。研究人员提出，改善大脑循环是有氧运动对认知产生长期影响的中介，但运动对认知和大脑灌注的即时影响还没有很好地描述，而且在老年人中的影响还知之甚少。
49 名老年人被随机分为中等强度的有氧运动组或放松组。两组在年龄和心血管健康（最大摄氧量）方面相匹配。使用脉冲动脉自旋标记（pASL）磁共振成像（MRI）采集测量平均灰质血流（GMBF），使用具有递增负荷的具象 n-回任务测量工作记忆表现，在运动/休息前后进行评估。
无论活动类型如何，n-回任务的准确性都在运动/休息后从之前提高。与对照组（休息）相比，运动后 GMBF 下降。在运动组中，运动后 n-回表现较高与右侧海马体、左侧内侧额皮质和右侧眶额皮质的 GMBF 较低有关，而心血管健康较高与 GMBF 较低有关。
在运动后不久，年轻成年人中报告的 GMBF 下降也发生在老年人中，与心血管健康有关，这可能支持了心血管健康与老年人大脑血管反应性之间的联系。
