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The purpose of this study was to examine the relationships between running performance and the cross–sectional area of the psoas major, peak oxygen uptake, and running economy in male junior long–distance runners. The subjects were 37 male junior athletes who achieved good records in interscholastic athletic competition during 5 years (2011–2015). Their seasonal best times in a 5,000 m race (5,000m–SB) were 14:04.11 ± 0:07.25 (13:53.64–14:16.15). In a multiple regression analysis, 5,000m–SB was statistical significantly correlated with the cross–sectional area of psoas major (16.0 ± 1.7 cm<sup>2</sup>) measured on magnetic resonance imaging and peak oxygen uptake (4.25 ± 0.36 l min<sup>-1</sup> [76.9 ± 5.8 ml min<sup>-1</sup> kg<sup>-1</sup>]) during a lactate curve test comprising five stages. However, 5,000m–SB was not related to oxygen uptake at the work–load which was less than the load at the lactate threshold estimated by using the lactate curve test results. These results suggest that a high volume of the psoas major, the largest hip–flexor muscle, and peak oxygen uptake are among the important factors for junior long–distance runner performance.
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Background: The beneficial effects of exercise on plasma lipids have been widely explored. These changes depend upon the type of sports in which one is indulged. The aim of the present study was to analyze these changes in different sportspersons. Methods: 32 male sportspersons participating in 3 different games in the university were selected for this study. Lipid profile of the three groups was compared to each other. Results : Total Cholesterol (TC), Triglyceride (TG) and Low Density Lipoprotein (LDL) levels were found to be significantly lower in distance runners as compared to football players and basketball players . Whereas High Density Lipoprotein (HDL) level was found to be significantly increased in runners as compared to other groups. Conclusion: The results of this study suggest that the lipid profile is more favourable in sports involving more aerobic activity with less physical stress.
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College athletes often tend to suffer from defective nutrition status due to excessive physical training with inadequate dietary intakes, which resulted in various physical disorders such as anemia. This study was conducted to investigate the effects of nutrition interventions to the anemic state of long distance runners. A nutritional education program was applied and daily single pack of nutritional supplement drink rich in iron, zinc, copper, selenium as well as eleven vitamins were provided for two months. Blood hemoglobin, red blood cells as well as serum ferritin and iron levels after the intervention were significantly higher compared with the basal, pre-intervention level of respective items. Among the subjects, two were found to be anemic (hemoglobin<13g/dl) before the intervention. Both of them, however, were successfully recovered to normal status (hemoglobin≧13g/dl) thereafter. The pre-intervention levels of hemoglobin were negatively correlated to the amount of difference between those of pre- and post-intervention, which appeared to indicate an improvement of nutrient deficiency that caused the hypochromia. On the other hands, the intake of energy and nutrients from meals did not change before and after the intervention. From the results obtained, it seems to be appropriate to emphasize the importance of nutrition education, especially, a possible effectiveness of including multiple nutrient supplementation in nutrition program for college athletes is suggested.
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The purpose of this study was to examine the influence of autostretching and static stretching on range of motion (ROM) and running economy (RE) in long-distance runners. Twenty-two male distance runners were randomly assigned to an autostretching group (n=8), a static stretching group (n=7) and non-intervention control group (n=7). The experimental protocol was composed of interventions between treadmill runnings for RE. The interventions were either autostretching or static stretching, after the first treadmill running. The oxygen consumption (VO<sub>2</sub>) as RE was measured at three steady-state running speeds (240m/min, 268m/min, and 295m/min). Goniometric measurements of hip flexion and ankle dorsiflexion ROM were taken immediately before and after each treadmill running for RE. The results showed that the autostoretching group had a significant decrease in VO<sub>2</sub> at 240m/min (p＜0.05), and at 268m/min (p＜0.05). On the other hand, the control group had a significant increase in VO<sub>2</sub> only at 295m/min (p＜0.05). At the same time, the autostretching group had significant improvements in ROM for hip flexion (p＜0.05) and ankle dorsiflexion (p＜0.05). The static stretching group had no significant changes in RE or ROM. The results of this experiment suggest that autostretching had a positive effect in improving RE in subjects of this study, and indicate the possibility that improved RE leads to the improvement of long-distance runners' performance.
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Objective To study the effects of Grape Procyanidins(GPC)on hemorheology in long distance runner.Method In vitro study: 22 long distance runners were divided into two groups randomly,the experimental group and control group.With ten days period,the experimental group was given GPC 200 mg per day;while the control group were given the capsule of starch 200 mg per day.In vivo study: the vein blood samples were taken from 5 long distance runners and every example was divided into five parts,and then treated with different concentrations of GPC or H2O2.Items of the hemorheology such as Er,HCT,Eb,Ep,PFC and VAI were tested both in vivo and vitro before and after the study.Results in vitro study: all items of the experimental group showed significant decline at then end of the study than those before the study.The contents of Er,Eb and Ep before the study(6.830?0.164,4.145?0.177,1.647?0.020,respectively) were significantly higher than those after the study(6.759?0.158,4.088?0.173,1.621?0.013,respectively)(P
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This study was carried out to compare the nutrient intake, urinary excretion of mineral (Na, K, Ca, Mg, Zn, Fe, Cu ), and the ratios of creatinine (Cr), body mass index (BMI) and basal metabolic rate (BMR) to the amount of mineral in 24-hour urine between both the male university students with few exercise (non-exercisers) and male university distance runners. The propriety of ratios of Cr, BMI and BMR was also examined in order to estimate intake of mineral for the male university distance runners.<BR>There were no significant differences in the intakes of energy, protein and carbohydrate between the both groups of subjects, and those major nutrients were at reasonable levels for the both groups of subjects. On the other hand, neither the intake levels of VB<SUB>6</SUB>, Ca, Mg, and Cu in the non-exercisers, nor niacin, Mg and Cu in the male university distance runners reached the level of Recommended Dietary Allowance for the Japanese. The intakes of retinol, VB<SUB>1</SUB>, VB<SUB>6</SUB> and Ca were higher in the male university distance runners than in the non-exercisers. The urinary excretion and excretion ratio to intake of Zn, excretion ratio of Na, ratios of Cr, BMI and BMR of Zn, and Cr ratio of Na were higher in the non-exercisers than those in the male university distance runners. So as to achieve the same levels of Cr ratios of Ca and Zn as the non-exercisers, the male university long distance runners should take larger amounts of those minerals than the non-exercisers. It was suggested that the ratio of BMR rather than that of Cr ratio to urinary excretion of mineral would be suitable for the estimation of a desirable intake level of mineral for the male university distance runners.
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To determine the zinc (Zn) status in long distance runners during the period after the running season, Zn balance was measured in 12 male student long distance runners for five days. Daily dietary intake of energy and Zn were 3000 kcal and 38 mg, respectively. Twenty-four-hour urine Zn excretion exceeded the standard value, the serum Zn concentration was within the normal range, and the sweat Zn concentration was relatively low, but prominently positive Zn balances were observed 11 of the 12 subjects. These results suggest that the Zn status in long distance runners during runnning season is low or deficient.
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This study was conducted to assess body composition and somatotype in elite female distance runners and to investigate the relationship between body composition and somatotype. Nine elite female distance runners (21.6±2.7 yrs) and 10 female college students (21.4±0.5 yrs) as a control group participated in this study. Body composition was estimated in terms of total body water based on the analysis of dilution of orally ingested deuterium oxide (D<SUB>2</SUB>O) in urine. Somatotype was estimated by Heath-Carter method.<BR>The skinfold thickness in distance runners were significantly thinner at 14 sites than those of the control group. The mean subcutaneous fat in distance runners was 4.1±1.6 kg (8.6±2.8%), which was significantly lower than that of the control group (9.4±3.0 kg & 17.2±3.8%) . The mean internal fat in distance runners was 7.2±2.0 kg (15.5±3.5%), which tended to be lower than that of the control group (8.2±1.5 kg & 15.4±2.2%) . The mean fat mass and percentage of body fat in distance runners were 11.3±3.1 kg and 24.1±4.7%, respectively, which were siginificantly lower than those of the control group (17.6±4.2 kg & 32.6±5.2%) . On the other hand, somatotype scores in distance runners were 2.35-2.32-3.82, suggesting more ectomorphic. In addition, fat mass positively correlated with the first component (r=0.890-0.916, p<0.05), and negatively correlated with the third component (r=-0.635--0.818, p<0.05) . The subjects who were more ectomorphic had less fat mass. However, the second component that was mesomorphic had no significant correlation with lean body mass. And the mean lean body mass in distance runners was almost the same as that of the control group (35.1±2.5 kg & 36.1±3.5 kg) .<BR>The results of this study suggest that although endurance training done by elite female distance runners does not increase their lean body mass, it has a great influence on their subcutaneous fat.
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A study was undertaken to determine whether the specific change in the ratio of systolic to diastolic time (QS<SUB>2</SUB>/DT) observed during prolonged exercise<SUP>17)</SUP> is dependent on HR or elapsed time, and also to elucidate the possible relationship between change in QS<SUB>2</SUB>/DT and distance-running performance. Twelve male distance runners were divided into two groups, a high- (HP Group) and a low-performance (LP Group) group, according to their 10, 000-meter running performance. They performed 60-min exercise on a bicycle ergometer at a work load controlled so as to keep the HR at 150 bpm. HR, systolic time intervals (STIs) and DT were calculated from electrocardiogram, phonocardiogram and the derivative of ear densitogram.<BR>In the time course of QS<SUB>2</SUB>/DT, two crests were formed at 2 and 15 min after the start of exercise, and also two troughs were formed at 10 and 20 min. Some of these troughs and crests formed even when HR was kept constant. Patterns of change in QS<SUB>2</SUB>, DT, QS<SUB>2</SUB>/DT and other parameters were similar in the two groups. However, the absolute values of the parameters differed. QS<SUB>2</SUB>, left ventricular ejection time (LVET) and QS<SUB>2</SUB>/DT in the HP Group were lower than those in the LP Group, whereas DT in the HP Group was longer than that in the LP Group.<BR>From these findings, it was concluded that the specific change seen in QS<SUB>2</SUB>/DT during prolonged exercise is dependent not on the HR level but on elapsed time. The changes in STIs and DT during prolonged exercise are thus influenced by the distance-running performance of the subjects.
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The purpose of this study is to investagate the meaning of systolic time intervals (STI) in evaluating cardiac functional condition of athletes.1. STI and step test were examined on 13 sprinters, 8 jumpers, 5 throwers and 5 distance runners during early, middle and the last phases in summer training season.No significant changes of the left ventricular ejection time (LVET), the pre-ejection period (PEP) and PEP/LVET ratio were found from examinations on athletes in the three different phases.The cases were divided into two groups of PEP/LVET ratio increased more than 0.05 (N=8) and PEP/LVET ratio decreased more than 0.05 (N=10) by the different of PEP/LVET ratio between linked phases examinations. Athough two of PEP/LVET ratio of each group were different evidently (P