ABSTRACT
The purpose of this study was to investigate the relationships between muscle mass or muscle power and bone mineral density in 43 postmenopausal women. Single photon absorptiometry was used to measure the bone mineral density and bone width of the calcaneuse. Isotonic muscle power of knee extensions (KE), knee flexions and incline squats (ISQ) were measured, using the power processor (VINE Co., Ltd.) . Statistical analysis demonstrated a significant positive correlation (p<0.05) between bone mineral density and lean body mass or muscle thickness. Although, bone mineral density was not significantly correlated with body mass index or fat mass, it was significantly corre-lated with leg muscle power. Further, the bone mineral density was also positively correlated with muscle contraction speed in the motion of KE (p<0.01) and ISQ (p<0.05), but not with muscle strength. This data suggest that the bone mineral density is closely related to the muscle power and/or speed rather than the muscle strength in postmenopausal women.
ABSTRACT
For endurance exercise in swimming mice, 1.8% VAAM (<I>Vespa</I>amino acid mixtiure) which has the same amino acid components as hornet (<I>Vespa</I>mandarinia) larval saliva, 1.8% casein amino acid mixture (CAAM), 10% glucose, or amino acid mixtures in which the amino acids were varied while maintaining the same molar ratio as VAAM were administered orally to mice. Mice recieving 1.8% VAAM showed significantly longer maximum swimming times than mice receiving other nutrients. Among these nutrients, mixtures of proline, glycine, and essential amino acid mixture (EAAM) from the VAAM component, showed maximum times near those with VAAM. In swimming exercise in mice earring of 0.3g tail weight, mice administered 1.8% VAAM showed lower blood lactate concentrations and higher blood glucose concentrations than mice recieving other nutrients. Mice recieving 1.8% VAAM also had lower lactate concentrations in muscle as well as blood. This suggests that VAAM suppresses lactate production and glucose catabolism during exercise. The effects of hornet larval saliva were stronger than those of VAAM. VAAM therefore showed the major effect of the saliva. The results suggest that VAAM improves physiological condition during endurance exercise. A positive correlation was observed between the blood concentrations of lactate and glucose in exercising mice administered various nutrients (r=0.779) . This suggests metabolic equilibration between glucose and lactate during exercise. A positive correlation (r=0.507) was also found between the maximum swimming time and blood glucose concentration. Maximum swimming times were highest at low (Ca. 2.5 mMol) and high (Ca. 4.0 mMol) blood lactate concentrations in high blood glucose concentrations. These facts support that glucose homeostasis is important in prolonged exercise.
ABSTRACT
For endurance exercise in swimming mice, 1.8% VAAM (<I>Vespa</I>amino acid mixtiure) which has the same amino acid components as hornet (<I>Vespa</I>mandarinia) larval saliva, 1.8% casein amino acid mixture (CAAM), 10% glucose, or amino acid mixtures in which the amino acids were varied while maintaining the same molar ratio as VAAM were administered orally to mice. Mice recieving 1.8% VAAM showed significantly longer maximum swimming times than mice receiving other nutrients. Among these nutrients, mixtures of proline, glycine, and essential amino acid mixture (EAAM) from the VAAM component, showed maximum times near those with VAAM. In swimming exercise in mice earring of 0.3g tail weight, mice administered 1.8% VAAM showed lower blood lactate concentrations and higher blood glucose concentrations than mice recieving other nutrients. Mice recieving 1.8% VAAM also had lower lactate concentrations in muscle as well as blood. This suggests that VAAM suppresses lactate production and glucose catabolism during exercise. The effects of hornet larval saliva were stronger than those of VAAM. VAAM therefore showed the major effect of the saliva. The results suggest that VAAM improves physiological condition during endurance exercise. A positive correlation was observed between the blood concentrations of lactate and glucose in exercising mice administered various nutrients (r=0.779) . This suggests metabolic equilibration between glucose and lactate during exercise. A positive correlation (r=0.507) was also found between the maximum swimming time and blood glucose concentration. Maximum swimming times were highest at low (Ca. 2.5 mMol) and high (Ca. 4.0 mMol) blood lactate concentrations in high blood glucose concentrations. These facts support that glucose homeostasis is important in prolonged exercise.
ABSTRACT
The effects of voluntary exercise on resting systolic blood pressure and vascular lesions of stroke-prone spontaneously hypertensive rats (stroke-prone SHR) were investigated with and without 1 % saline loading. Forty male stroke-prone SHR aged 7 weeks were assigned to one of 4 experimental groups. Each consisted 10 animals ; sedentary control (S), sedentary with 1 % saline loading (SS), exercised control (E), and exercised with 1 % saline loading (ES) . Animals were sacrificed at the 5 th week. In the prehypertensive phase, resting caudal arterial systolic blood pressure was significantly lower in the E group than in the S group. However, after being loaded with 1 % saline, the ES group showed higher resting systolic blood pressure than those of the SS group. In addition, the ES group revealed severer renal, myocardial, and cerebrovascular lesions than those of the rest of the groups.
ABSTRACT
In this study, we investigated the effect of exercise training on serum and liver chblesterol levels and on biosynthesis of liver cholesterol in rats. The training was carried out at low [Low-Ex, 60% max O<SUB>2</SUB> consumption (VO<SUB>2</SUB>) ] and high (High-Ex, 75% max VO<SUB>2</SUB>) intensities for 16 weeks. The energy expenditure was adjusted to be equivalent. The succinate dehydrogenase activities of gastrocnemius muscle in the Low-Ex group and High-Ex group were higher than that of control, 36% and 109% (p<0.05) respectively. The levels of total and high density lipoprotein cholesterol in serum were 14-26% lower than those of control, but no difference was detected between the trained groups. The activity of HMG-CoA reductase in liver microsome was significantly higher than that of control for both trained groups. However, the stimulation of this enzyme activity was not changed by training intensity.
ABSTRACT
The effect of voluntary exercise training and influence of saline loading on blood pressure and cholesterol metabolism in rats were investigated in this study. Experimental animals used were male Wistar strain rats, aged 7 weeks old. These rats were allocated respectively into four groups, each of which consisted of 10 rats; sedentary control (SC), sedentary with 1 % saline loading (SS), training control (TC), and training with 1 % saline loading (TS) . In each of groups rats were sacrificed at the 10 th week.<BR>Following results were obtained in this study.<BR>1) The mean values of systolic blood pressure remained unchanged in all four groups, 2) serum and hepatic cholesterol levels were lowered by 10 weeks of exercise training, 3) the ratio of HDL-cholesterol to total cholesterol increased significantly in the training groups compared to that in the sedentary groups, 4) the incorporation of <SUP>14</SUP>C-acetate into liver cholesterol was significantly lower in the SS group than in the SC group, and 5) a direct correlationship was found between the increased exercise level and the incorporation of acetate into liver cholesterol in both TC and TS groups.