ABSTRACT
The purpose of this study was to assess the status of nutrients intake in male Japanese collegiate athletes. Each 20 of baseball (B), soccer (S), volley ball (V), and long distance (L) athletes participated in this study. The B, S, and V athletes lived by themselves, whereas the L athletes lived in an athletes dormitory with provided meal. The nutritional status was assessed for 2 days. Mean energy intakes in the B, S, V, and L groups were 43.6, 53.7, 47.0, and 55.0 kcal/kg body weight, respectively. Mean protein intakes were 1.2, 1.6, 1.3 and 2.4 g/kg, respectively. In B athletes, skipping of breakfast was recognized frequently. Most of micronutrients intakes in the B, S, and V groups were less than the recommended dietary allowances for athletes. We suggest that a provided meal system is a better system for collegiate athletes and more nutritional education is necessary for Japanese male collegiate athletes, in particular, those living by themselves.
ABSTRACT
In this study, we investigated the effects of prolonged voluntary running training on bone mass in the tiba of growing male SD rats. At 5 weeks old, the rats were divided into 4 groups : group 15 VE (n=7) exercised voluntarily on a running wheel for 10 weeks from 5- to 15-weeks old ; group 35 VE (n=7) exercised voluntarily on a running wheel for 30 weeks from 5- to 35-weeks old ; in groups 15SC (n=6) and 35 SC (n=5), rats were housed individually in normal plastic cages for the same periods as groups 15 VE and 35 VE, respectively. At the end of each experimental period, the right tibia from each rat was used for bone- mass analysis using peripheral quantitative cumputed tomography (pQCT) . The evaluated portions were the proximal methaphysis and the diaphysis, with total, cortical, and trabecular data from these portions being obtained as volumetric bone mineral content (vBMC) and volumetric bone mineral density (vBMD) . The results indicated that 1) although voluntary running distance tended to decline during the later period (1635 wk old) in 35 VE rats, some mean values obtained for bone mass parameters using pQCT were significant greater in 35 VE than in 35SC ; 2) the mean values from those parameters in 15 VE were not significantly different from those in 15 SC. These results suggest that the continuation of voluntary exercise may be important for bone- mass enhancement in rat tibia.
ABSTRACT
We examined the effect of running training on regional cardiac myosin isozyme composition in rats. Male Sprague-Dawley strain rats (4 weeks old) were used, and divided into two groups: sedentary control (C) and trained (T) groups. The T group was trained by treadmill running (40 m/min, 1h/day, 5 days/week, for 12 weeks) . At 16 weeks old, their hearts were excised. The left ventricle was separated into the subendocardium (Endo) and subepicardium (Epi) by dissecting the ventricle at the mid-wall. The ventricular myosin isozymes were examined by electrophoresis on pyrophosphate gel under non-dissociating conditions. The results showed the following: 1) The relative heart weight of the T group was significantly higher than the C group. 2) Left ventricular myosin isozyme composition showed a region-specific distribution in the C rats, and the proportion of V3 myosin or β-myosin heavy chain in the Endo was significantly higher than that of the Epi. However, the training had no effect on the cardiac myosin isozyme in either portion. 3) The activity of citrate synthase did not show transmural gradient in the ventricle of C animals. Training had no effect on the activities of either portion. 4) The activity of lactate dehydrogenase (LDH) showed transmural gradient in the ventricle of C rats. Training-induced changes in the activity of LDH were found in both portions, therefore, training abolished the transmural gradient in the activity of LDH, suggesting a corresponding redistribution of the myocardial work load.<BR>These results indicate that running training might induce the redistribution of the myocardial work load, whereas the stimulation apparently has no effect on the regional distribution of cardiac myosin isozyme composition.
ABSTRACT
Long term physical training is known to cause a change of cardiac functions and this effect is observed at various levels of the heart (from whole heart to subcellular level), although its mechanism is not fully understood. It is reported that cardiac hypertrophy and decreased heart rate can be observed as effects of long term physical training, but change of the catecholamine content in heart tissue induced by training is controversial.<BR>In the present experiment, long schedule of short daily swimming episodes was employed to observe the effect of mild physical training on cardiac functions of rats in the growing stage. We measured body weight, heart weight, heart rate under light anesthesia, variation of R-R-interval of electrocardiogram, and catecholamine contents in cardiac muscle.<BR>1) Wister rats were divided into 2 groups 3 weeks after birth. One group rats was kept sedentary in cages, and the other group was required to free swim in a tank containing water at 30°C. At the beginning of the programme, swimming time was 10 min. Swimming was applied 5 days a week for up to 14 weeks, and swimming time was gradually increased to 30 min.<BR>2) Body weight of rats in the trained group was significantly less than that of the controls, and the heart weight to body weight ratio in the trained rats was significantly higher than in the controls.<BR>3) In the exercised rats, the R-R interval of the ECG was longer than that of the controls, and there was a tendency for the variation of R-R interval in the trained group to be larger than that of the controls.<BR>4) At 10 and 17 weeks, rats from each group were sacrificed after or without a 30 min test swim for measurement of catecholamine content of the ventricular muscle. One time swimming for 30 min increased dopamine content, but did not change norepinephrine content except for the trained group at 10 weeks. There was no significant difference in cardiac catecholamine contents in the rested state of the control and trained groups at 10 and 17 weeks.<BR>5) Results were interpreted as follows: One time swimming for 30 min influences the activity of the autonomic nervous system innervating the heart, and catecholamine metabolism at nerve terminals of the sympathetic nervous system. Long term mild swimming does not cause permanent change of catecholamine contents, and the low heart rate in the trained group cannot be soley explained by the decreased activity of the sympathetic nervous system.
ABSTRACT
Triglyceride contents of liver, heart muscle and skeletal muscles (rectus femoris, tibiaris anterior, soleus, plantaris and extensir digitrum longus) were determined on 1, 3.5, 14, 18 and 21 months-old rats, and especially on 14 and 21 months-old rats composition of triglyceride fatty acids was analyzed and interrelation of these triglyceride contents with aging of rats was studied quantitively and qualitatively. Following results were obtained<BR>1) Changs in liver and muscular triglyceride contents appeared on 14 months-old rats and were significant increase at 21 months-old rats.<BR>2) Liver triglyceride content significantly decreased at 21 months-old rats (p<0.05) .<BR>3) lrriglyceride contents of tibiaris anterior and extensor digitrum longus muscles were mostly unchangeable through the aging of rats.<BR>4) But triglyceride contents of soleus, rectus femoris and plantaris muscles in 21 months-old rats significantly increased (p<0.05) and the individual difference was great.<BR>5) In composition of triglyceride fatty acids, increase of C<SUB>18</SUB>, C<SUB>18-1</SUB>, C<SUB>18-2</SUB> and C<SUB>18-3</SUB> was observed in epididymal adipose tissue, soleus and rectus femoris muscle on 21 months-old rats, but in extensor digitrum longus and tibiaris anterior muscles.<BR>From these results, changes of tissue triglyceride contents with aging of rats are different in each tissue and increase of triglyceride content is present with qualitative changes in composition of triglyceride fatty acids, increase of long chain and unsaturated fatty acids, and organic specificity, which is related to the functional changes with aging of rats is considered.
ABSTRACT
Students and general long distance runners carried out 1600m run for 24 hours and their physical functions were measured with lapse of the relay. Following results were obtained.<BR>1) Prolongation of mean running time of student long distance runners in 1600m runs appeared at about 8th-10th runs, 12.8-16.0km, but that of general long distance runners did at 5th-6th runs, 8-9.6km.<BR>2) There was plus correlation between mean of running time and its standard deviation in 1600m runs. It was r=0.55 and its regression equation was Y=0.58X-162.3. But these of general long distance runners were r=0.53 and Y=0.358X-97.3, respectively.<BR>3) Decreased body weight from 1st-8th run was great and succesive, and occupied about 30%-70% of final decreased body weight. Thereafter, increase or decrease of the body weight was repeated and the time course became slow. There were some runners who showed large and succesive decreased body weight with the runs through the competition. The decreased body weight during the competition was influenced by the wind velocity, which supressed it considerably.<BR>4) Heart rate of a student long distance runner during 1600m run reached 180-189 beats per minute every run. Resting heart rate of general and student long distance groups showed circadian rhythm during the competition, but that of student runners was higher through the competition and their systolic pressure shows a tendency to below in later period of the competition.<BR>5) Threshold of knee jerk was low in the initial few runs and thereafter showed circadian rhythm. Reaction time to light was also facilitated in the initial runs and there-after prolonged about 30msec and maintained till the end of the competition. Frequency of subjective symptoms increased with number of the runs. At middle of the competition, it came over Sakai's standard and the A, B and C symptoms at the end of the competition were 33.0%, 20.0% and 25.0%, respectively.<BR>6) Calorie intake per day of the student long distance runners was in the range of 1240-2540Cal. Total energy consumption was estimated 7457Cal. per day.<BR>7) Blood glucose of the student long distance runners mostly unchanged through the competition, but serum triglyceride and total phospholipids significantly decreased and inversely serum free fatty acids prolongly mobilized.
ABSTRACT
34 male rats (13 weeks old) were used in this experiment. 11 rats were at rest and 23 rats were loaded to run on a treadmill with 2 degree slope at a speed of 25m/min. Relation between quantities of blood substances (plasma glycerol, blood lactate and plasma free fatty acids ; FFA) and lipolytic activity of epididymal adipose tissue was studied to clarify a mechanism of lipolysis of the adipose tissue in the exercise.<BR>1) Plasma FFA and glycerol began to increase in parallel at 30 min after the run, but at exhaustion only plasma glycerol enhanced.<BR>2) Blood lactate increased at 10 min after the run and more at exhaustion.<BR>3) Basal lipolytic activity of epididymal adipose tissue in vitro was not influenced by the run, while norepinephrine induced lipolysis of the adipose tissue decreased with lapse of running time. Relation between plasma FFA and lipolytic activity of epididymal adipose tissue was inverse during the run.<BR>4) There was also inverse relation between blood lactate and lipolytic activity of adipose tissue induced with norepinephrine. From these results, it is assumed that the increase of plasma FFA during the exercise was not resulted from the increase of lipolytic activity of the adipose tissue stimulated with only norepinephrine and effects of other hormones (ACTH, Glucagon, Growth hormone and etc.) and their interactions on the lipolysis might be considered.
ABSTRACT
Lipolytic activity of adipose tissue with age has been widely investigated by many authors. There are differences on the conception of intrinsic lipolytic activity of a cell changed with aging. Since lipolytic activity has been expressed by amount of FFA release per wet weight, per triglyceride or per protein, increase of triglyceride or wet weight seems to be a main factor to affect on it. It is of interest, therefore, to investigate the intrinsic lipolytic activity of adipose tissue with aging from the relationship among FFA release, wet weight, protein and triglyceride content in adipose tissue.<BR>In the present paper, we investigated effect of aging on lipolysis by using epididymal adipose tissue in 29, 35, 43, 57, 105 and 350 days rats. Rats were anesthetized by intraperitoneal injection of pentobarbital sodium (4mg/100g body weight) and after that epididymal adipose tissue were removed and washed out the blood by 25°C Krebs-Ringer solution. The fat pads were placed in glass bottles containing Krebs-Ringer bicarbonate buffer solution (pH 7.2-7.4), bovine serum albumin (4°C/ w/v) and epinephrine (3.9 pM/ litre) . Incubations were carried out in a shaking water bath for 120 min at 37°C under an atmosphere of 95% O<SUB>2</SUB>-5% CO<SUB>2</SUB>. Rate of lipolysis were determined by assaying the production of free fatty acids. Free fatty acids were titrated by Dole's method. Triglyc-eride and protein content in fat pads were assayd by Stern and Shapiro's method and Lowry's method, respectively.<BR>The following results were obtained<BR>1) Triglyceride-to-wet weight ratio and triglyceride-to-protein ratio in the adipose tissue corresponded to age (days) remarkably increased between 35 days and 43 days rats. However, after that, triglyceride-to-wet weight ratio was unchanged up to 350 clays rats.<BR>2) Maximum lipolytic activity of adipose tissue in rats with aging was observed at 29 days in the range studied and after that its lipolytic activity decreased with aging. This decreased phase of lipolytic activity seemed to be divided into two phases : one was fast decrease phase which was observed in the rats before 43 days, and the other was slow decrease in the rats after 57 days.<BR>3) Relationship between lipolytic activity and triglyceride-to-protein ratio in adipose tissue during aging showed inverse curvelinear relation, and it was found that lipolytic activity of adipose tissue was extremely inhibited at triglyceride-to-protein ratio more than ten.<BR>From these results, we assumed that increase of triglyceride content in adipose tissue was related with the decrease of lipolytic activity during aging and that the lipolytic activity of adipose tissue would be enhanced with decrease in triglyceride-to-protein ratio inversely.