ABSTRACT
The present study examined the relationship between rate of abnormal menstrual cycles in women who participated in competitive sports and long-term fertility. Longitudinal menstrual data were collected over 25 years from 33 women who graduated from physical education collegesThe results were as follows:1)Among the 33 women surveyed, the number of pregnancies for each woman ranged from zero to eight; the total number of pregnancies was 85 (mean 2.6). Sixty-five (76.5%) of the 85 pregnancies were carried out to delivery times.2)The rate of spontaneous abortion was 15.3%. Four (12.1%) of the 33 women were infertile.3)In women with fertility-related problems such as infertility, spontaneous abortion, premature delivery, and stillbirth, the rate of abnormal menstrual cycles tended to be higher with increase of the fertility-related problems.4)In women with a high rate of abnormal menstrual cycles during college, the rate continued to be high after graduation.5)In women without fertility-related problems, the rate of abnormal menstrual cycles during college varied widely. Also, the rate of abnormal menstruation decreased less than 30% after graduation, excluding one woman. Conversely, in women with fertility-related problems, the rate of abnormal menstrual cycles was higher than in women without fertility problems both during college and after graduation.6)Changes in menstrual cycle length with age were more different than an individual. In women with fertility-related problems, abnormal menstrual cycles were observed between the ages of 18 and 42, and abnormal cycles were both longer and shorter than normal cycles.The results indicated that, in women who participated in competitive sports during their youth, abnormal menstrual cycles may remain long after retirement from sports. In addition, problems such as infertility and spontaneous abortion were observed to be associated with higher rates of abnormal menstrual cycles.
ABSTRACT
The present study was to evaluate endothelial nitric oxide synthase (eNOS) protein expression and hemodynamics of pulmonary circulation in rats of "Living high and Training low" (LH+TL). The Sprague Dawley strain of male rats were used at the age of 9 weeks. They were divided according to four conditions of a living low (LL) group, living low and training low (LL+TL) group, living high (LH) group and LH+TL group, for 10 days. We assessed the effects of LH+TL on exercise-induced pulmonary arterial pressure and blood lactic acids under sea-level altitude in catheter-implanted conscious rats. Also, we measured the pulmonary artery under anesthesia and analyzed eNOS protein expression by western blot analysis. The blood lactate levels in the LH+TL rats decreased after maximal treadmill running compared to LL, LL+TL and LH rats (p<0.05). The increase in pulmonary arterial blood pressure with exercise was significantly lower in the LH+TL group than in the LL group (p<0.05). The eNOS protein expressions of pulmonary artery were higher in the LH+TL group than in the LL group (p<0.05). This study indicates that LH+TL reduced the increase of pulmonary arterial blood pressure with exercise at below sea-level altitude. In addition, eNOS protein expressions were enhanced in the pulmonary arteries of LH+TL rats. Thus, we conclude that the high altitude training of LH+TL was a useful method for improvement of endurance exercise ability and this improvement may be associated with pulmonary arterial response.
ABSTRACT
This study was undertaken to compare the effect of the pre-exercise intake of a dry egg white protein supplement (86 kcal) on the post-exercise alterations in leukocytes and the plasma interleukin-6 (IL-6) concentrations in male collegiate runners. The 43 runners who participated in this study were divided into 2 groups, namely those with (E groups) and without (C groups) a 12,000 m pace run, and then they were further divided into 4 subgroups in which the subjects were given the 86 kcal nutrient supplemented including either 0, 5, 10, or 20 g protein from egg white. Peripheral blood samples were collected before supplementation (Pre), just after running (Post 0h), and at 1 h after running (Post 1h). The concentrations of the leukocytes, neutrophils, and monocytes in both groups E and C remained unchanged at Post 0 h. Furthermore, these concentrations increased significantly at Post 1 h. The lymphocytes were not significantly different at Pre. The plasma IL-6 concentrations were significantly higher at Post 0 h than at Pre or Post 1 h. In addition, no effect of the protein supplementation on the leukocytes, leukocytes subsets, or the IL-6 concentrations was observed. These observations suggested that such isocaloric supplementation as described above may therefore be able to help control the changes in the concentrations of leukocyte and leukocyte subsets immediately after running a 12,000 m time trial.
ABSTRACT
Purpose : This study was undertaken to clarify the effect of heme-iron supplementation on the prevention of iron-deficiency anemia in male collegiate distance runners.Methods : Forty-one male collegiate runners were divided into three groups, consisting of a heme-iron group (HI), a citrate-iron group (CI), and a non-iron group (NI). Iron tablets (heme-iron or citrate-iron) were administered at a dose of 7 mg per day for two months. The blood components and nutritional intakes were estimated before and after the intervention.Results : The nutritional intakes did not differ among the three groups. The red blood cell, hemoglobin, hematocrit, ferritin, Glutamic-Pyruvate Transferase and <i>γ</i>-Glutamyl Transpeptidase levels were unchanged throughout the experimental periods. After the intervention, the serum iron levels significantly decreased in the NI group but not in the iron-supplemented groups, while the reticulocytes counts increased among the three groups.Conclusion : The small amount of heme-iron supplementation was thus found to have a preventive effect on iron deficiency anemia without causing any negative side affects.
ABSTRACT
This study reviewed the influence of hypoxic training on hypoxic pulmonary vasoconstriction (HPV) sensitivity in the isolated perfused lungs preparation of rats. In addition, the study examined the kind of mechanism involved. Therefore, we inhibited nitric oxide (NO) release of endothelial cells, using on NO synthase inhibitor, and reviewed the impact on HPV.As a result, the following became clear. 1)Hypoxic training inhibited HPV. 2) HPV was increased by the administration of NO synthase inhibitor L-NMMA, in particular, conspicuously inhibited HPV in the hypoxic training group was increased. 3) The negative correlation between the onset of blood lactate accumulation and HPV was significant.From the above, it can be concluded that hypoxic training inhibited HPV and NO release for a pulmonary vascular endothelial cell. In addition, we understood that HPV was decreased by hypoxic training as the ability for endurance exercise was increased.
ABSTRACT
Previously, we observed that hypoxic pulmonary vasoconstriction (HPV) can be reduced by endurance exercise training. This study determined whether nitric oxide (NO) plays a role in inhibition of the HPV after endurance exercise training in isolated rat lung perfused with physiological saline solution containing meclofenamate. Sprague-Dawley rats were used, and were divided into two groups: a control (Cont) group and an endurance exercise-trained (ET) group. Endurance exercise training was carried every day on a small-animal motorized treadmill. The training protocol was 30 to 40 min/day and the rats ran at a speed of 15 to 30 m/min for 2 weeks. It appeared that HPV could be reduced by short-term endurance exercise training. The NO-forming enzyme inhibitor, N<SUP>G</SUP>-nitro-L-arginine methyl ester (1.5×10<SUP>-8</SUP>M, L-NAME), administered to the ET group increased the HPV compared in that of the Cont group. These findings indicate that endothelial NO synthesis may contribute to the inhibition of HPV in ET rats. Our data suggest that endurance exercise training promotes endothelium dependent-pulmonary vasodilation through the stimulation of NO released during HPV.
ABSTRACT
Sensory estimates of thermal sensation of exercising unclothed five healthy male subjects have been compared with the associated thermo-physiological responses at various ambient temperatures.<BR>The subjects were exercising at approximately 50% of their maximal oxygen intake 30 minutes in a handmade wind tunnel. Three levels of ambient air temperatures were used at about 20°C, 25°C, and 30°C. Relative humidity was always maintained at about 60%, and the air movement was kept constant at 0.1 m/sec.<BR>Physiological measurements were thermal sensation, skin temperatures (22 points), rectal temperature, local sweating rate and total sweating rate.<BR>The relationship between rectal temperature and mean skin temperature and the estimate of thermal sensation was described by a summation model, where the thermal sensation was linearly related to the rectal temperature and the higher levels of mean skin temperature shifted the former relation to the higher deretion.<BR>The subjective estimate of thermal sensation (Sense) during exercise has been described as a summation of thermal signals from the core (Tr : rectal temperature) and the skin (Ts ; mean skin temperature) as follows ;<BR>Sense=2.21 Tr+0.29 Ts-84.81 (r=0.869, p<0.001)<BR>Further, the linear thermal sensation-rectal temperature relationship was dependent on ambient air temperature during exercise.<BR>Increasing the maximal oxygen intake decreased the gain of the thermal sensationrectal temperature relationship at only 30°C air temperature.<BR>It was difficult to estimate the local sweating rate by the degree of thermal sensation during exercise.
ABSTRACT
To visualize skin temperatures during the dynamic and static arm exercises, a monochromatic thermograph was used.<BR>The thermoviewer JTG system presented a 5-monochromatic step-thermal display in centaral temperatures of 34.5 or 34.0°C and a temperature range of 2°C. The temperature resolving power of the system was 0.2°C. A 35 mm camera was used to take a synchronous thermogram of 2 sec scanning time.<BR>The experiments were carried out in August in an experimental room with an air temperature of 27.3±0.6°C, and a relative humidity of 50.5±4.3%.<BR>The skin temperatures of the forearm, upper arm and chest for five male subjects (18-25 yr) were observed before, during and after 5 min exercise on an arm ergometer at work intensities of 0, 2, 3 and 4 kg (dynamic exercise : a rate of 40 contractions/min as timed with a metoronome) .<BR>The following results were obtained.<BR>1) Changes in skin temperatures were observed in detail and over a wide area during the dynamic and static exercises.<BR>2) The upper arm skin temperature increased as soon as that of the shoulder fell immediately after the beginning of dynamic exercise.<BR>3) The decrease in skin temperatures on the chest, shoulder and upper arm appeared with static exercise.<BR>4) The fall in skin temperature increased and spread from forearm toward chest with the incresse in static work intensity.