The purpose of this study was to examine the effects of walking exercise on the mental activity of 44 elderly patients with slight, long-term cerebral infarction. Walking exercise, mental activity and brain morphology were determined by the number of steps taken per day, modified Hasegawa's dementia scales-R and computed tomography, respectively.
The results are as follows : The average number of steps taken per day for the group of normal mental activity was 3489±1692, for subnormal 2073±980, pre-dementia 1458±1241, and dementia 570±1132. Sylvian fissures enlargement ratio in the normal group was 4.3±1.7%, subnormal was 4.1±0.8%, predementia 6.0±2.3%, dementia 6.3±1.8%.
The difference between the right and left sylvian fissure enlargement ratio in the normal group was 1.8±0.9% (right) vs. 2.5±1.3% (left), subnormal: 1.7±0.4% (right) vs. 2.5±0.5% (left), predementia : 2.6±0.9% (right) vs. 3.4±1.5% (left), dementia: 3.0±1.2% (right) vs. 3.2±0.9% (left) . Cerebrum-cranial cavity ratio in the normal group was 80.6±5.0%, subnormal 78.6±5.0%, predementia 74.6±4.8%, dementia 72.7±3.4%.
The lateral ventricles-cranial cavity ratio for normal was 14.3±4.5%, subnormal 14.7±3.1%, predementia 17.3±3.6%, dementia 16.8±4.7%. The difference between good walking patients (over 1000steps/day) and poor walking patients (less than 1000steps/day) concerning the sylvian fissures-cranial cavity ratio (A), cerebrum-cranial cavity ratio (B) and lateral ventricles-cranial cavity ratio (C) was as follows: (A) 4.4±1.5% vs. 6.4±1.9% (p<0.001), (B) 78.4±6.7% vs. 74.0±3.4% (p<0.05), (C) 15.2±3.9% vs. 16.5±4.5% (ns) .
The above data indicates that there is an interrelationship among walking exercise, mental activity and brain morphology.