Time-of-day effects of ethanol consumption on EEG topography and cognitive event-related potential in adult males were studied. Ethanol (0.5 g/kg) or control drink was orally administered to nine healthy males at 10:00 and 18:00. The alpha2 amplitude was significantly lower than that of the control at 0.5, 2.5 and 4.5 hours after ethanol consumption in the morning. These effects were observed in the left hemisphere and were only found after consumption in the morning. The subjectively rated attention was significantly lower than that of the control at 0.5 and 2.5 hours after ethanol consumption in the morning and at 0.5 hours after ethanol consumption in the evening. In contrast, the search speed of serial search task and P300 amplitude was significantly lower than that of the control at 2.5 hours after ethanol consumption in the evening. These results demonstrate that effects of ethanol are dependent on time-of-day of consumption. Ethanol consumption significantly lowered the alpha2 amplitude when consumed in the morning, and lowered P300 amplitude when consumed in the evening.
It has been reported that activation of autonomic effectors during mental simulation of voluntary motor actions (motor imagery: MI) may be explained by two different factors, i.e., functions of preparation or anticipation of actual exercise (motor anticipation) and the central motor programming/planning which acts during actual motor action (motor programming). This study was designed to clarify how these factors participate during MI, utilizing two mental tasks with high mental stress, i.e., MI and mental arithmetic (MA). Several autonomic effectors' responses were compared between MI of a 500 m speed skating sprint and MA. Subjects were eight 18 to 25 year old young male speed skate athletes, all of them could easily and vividly imagine a 500 m speed skating sprint. Duration of the MI ranged from 35 to 38 sec and these were very close to each subject's actual best record (means of absolute differences were less than 0.6 sec, i.e., less than 1.7% relatively). A significant decrease of skin resistance (SR), increases of heart rate (HR) and respiration rate were observed in both MI and MA when compared to each control resting level (excluding one subject for respiration rate during MI). SR decreased during MI (mean and SD of 8 subjects: 45.9 ± 17.7%) and MA (39.7 ± 16.8%), with no significant differences between MI and MA (t=1.29, by paired t-test). HR increased significantly above control values in MA (10.3 ± 4.3%) and MI (44.3 ± 18.8%). However, the increase during MA was significantly smaller (t=4.99, p<0.001) than in MI. Respiratory rate increased significantly in both MI (46.5 ± 30.9%) and MA (27.7 ± 14.6%), with no significant difference between MI and MA (t=1.82) due to the large individual variation in MI. The frequency of respiration was fairly regular during MA, but quite irregular during MI (similar to those during actual motor actions). The central nervous system which acts in MI may possess the function of activation of target effectors which play an important role in actual exercise, on the basis of incremental vigilance level induced by the function of motor anticipation.
The questionnaire to determine the biosocial rhythms of daily living in the disabled elderly was newly developed. This questionnaire was aimed to evaluate a state of synchronization of biological rhythms in the disabled elderly. Eighteen items of the questionnaire relating to the synchronization of biological rhythms were finally selected by the test-retest method that was conducted for 68 disabled elderly living in a community with a duration of one year. The factor analysis showed that the questionnaire consisted of five factors: outdoor activities, ultradian rhythms, subjective evaluation of health status, social support, and sleep habits. The cumulative contribution rate of five factors was 53.2%. Reliability of the questionnaire was confirmed by a calculation of the Equal-length Spearman-Brown coefficients ranging from 0.60 to 0.80. Regarding the construct validity of the questionnaire, results of factor analysis showed five factors that were consistent with the synchronizers known in chronobiology. The total score of the questionnaire was significantly correlated to Barthel Index score and the competence score, suggesting that it partly reflects the activities of daily living of the disabled elderly. We conclude that a new questionnaire to determine the biosocial rhythm of daily living in the disabled elderly is useful to evaluate the biosocial synchronization of the disabled elderly because of its high reliability and validity.
Stroke-prone spontaneously hypertensive rats (SHRSP) induce spontaneous osteoporosis. To elucidate the specific characteristics of bone metabolism, the SHRSP was compared with age matched Wistar-Kyoto (WKY) rats. We investigated the effects of prolonged swimming exercise training on bone mineral density (BMD) and metabolism in the SHRSP. Seven-week-old male SHRSP and WKY were divided into three groups; the sedentary control WKY group (n=6, WKY), the sedentary control SHRSP group (n=6, SP) and the swimming exercise training SHRSP group (n=6, SWIM) (in pool with 60 min./day, 5 days/week for 12 weeks). The femoral BMD, bone mineral content (BMC), strength, Ca and P contents (%) of SHRSP were approximately 17, 27, 25, 20 and 9%, respectively, lower than that of WKY (p<0.001). Serum alkaline phosphatase (AlP) had not changed between both of SP and WKY, but tartrate-resistant acid phosphatase (TrAcP) of SP approximately 3-fold higher than that of WKY (p<0.05). Both serum calcium (Ca) and intact parathyroid hormone (i-PTH) were similar between SP and WKY. However, serum phosphate (P) of SP was approximately 180wer than that of WKY (N.S.). These results suggested that SHRSP induces osteopenia by the bone turnover of the promoted osteoclast activity with disturbed phosphate homeostasis. On the other hand, the femoral BMD and strength were approximately 7% and 20%, respectively, decreased in the SWIM (p<0.001), and femoral bone Ca and P contents (%) were also approximately 11% and 14%, respectively, lower than that of SP (p<0.001). There were no significant difference between SWIM and SP on serum Ca, but serum P of SWIM was significantly lower than that of SP (p<0.05). These results suggested that the prolonged swimming exercise training in the SHRSP induces more cruelly hypophosphatemia, and leading to osteopenia eventually. We conclude that SHRSP induces osteopenia with disturbance of phosphate homeostasis, and the prolonged swimming exercise in the SHRSP might deteriorate hypophosphatemia and osteopenia.
We attempted to determine the effectiveness of exercise prescription for women with hyperlipidemia (HL), because some HL women showed no significant improvement in serum lipid and lipoprotein profiles despite the continuation of exercise conditioning. We therefore tested the hypothesis that exercise can be clinically beneficial even when there are no alterations in total cholesterol (TC), low-density lipoprotein cholesterol (LDLC), and/or triglycerides (TG). Twenty-three women with HL (aged 54.3 ± 7.6 yr) participated in our outpatient-supervised exercise conditioning program for 90 minutes each session, twice a week for 1 year, and also did home-based exercise three days a week. Vital age (VA) is a useful index for assessing functional status, especially the risk of coronary heart disease (CHD) and is computed from 11 independent variables measured not only when a person is at rest but also during exercise. Although TC and LDLC did not change significantly after the exercise conditioning, TG decreased significantly (P < 0.05). Furthermore, when we computed the corrected VA (VAc) assuming no changes in TC, LDLC, and TG, VAc was found to decrease significantly from 64.0 ± 9.9 yr to 58.4 ± 9.0 yr (P < 0.05). In conclusion, these results indicate the effectiveness of exercise conditioning on risk of CHD in HL women, irrespective of alterations in the concentrations of serum lipid and lipoprotein.