The impact of water immersion recovery to the neck after short distance swimming on pulmonary functions in individuals with the past history of bronchial asthma / 体力科学

<p>The purpose of this study was to assess an impact of water immersion recovery after short distance swimming on the recovery process in pulmonary functions in individuals with the past history of bronchial asthma (PHA). Eleven Japanese healthy males with PHA (23 years) volunteered to perform two bouts of a 25-m maximal front crawl session in an indoor pool. The two bouts were separated by either 10-min of recovery on the land (L-session) or the same condition with water immersion to the neck (W-session), using a counterbalanced crossover design. Water temperature was 30 °C. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV_1.0) (%predicted) were measured according to the following time course; at baseline (REST), water immersion to the neck (WIN) before the swimming session, after 5-min (REC-5) and 10-min (REC-10) recovery with the assessment of dyspnea sensation (ADS) at the same time point. %FVC and %FEV_1.0 at WIN, REC-5 and REC-10 in the W-session were significantly lower than those REST. A similar reduction was observed at WIN in the L-session, and %FEV_1.0 at REC-5 was significantly different from those REST. The subjects had higher ADS at REC-5 in both sessions compared with those REST. %FVC and %FEV_1.0 at REC-5 and REC-10 in W-session were significantly lower than those at REC-5 and REC-10 in L-session. These results indicates a negative impact of not only water immersion recovery but also recovery on the land after short distance swimming on pulmonary function in individuals with PHA.</p>

The relationship between health-related quality of life measures, daily rhythm of oral temperature and lifestyle in young men / 体力科学

The purpose of the present study was to indicate the relationship between health-related quality of life (HRQOL) measures, the daily rhythm of oral temperature (OT), and lifestyle. Five-hundred young men volunteered to participate in this study. Their OT, measured using a digital thermometer, was recorded every 2h from the time they woke up to the time they went to sleep for 1 week. The daily rhythm of OT was calculated as a quadratic function using the 1-week data. The HRQOL was measured using the Short-Form 36-Item Health Survey version 2 (SF-36v2). The participants were divided into 3 groups: a high-value group (HG) with ≥ 55 points of each summary score and each subscale score, a middle-value group (MG) with score > 45 and < 55 points, and a low-value group (LG) with score ≤ 45 points. Lifestyle was assessed in terms of eating habits, sleeping and exercise, and the presence of unidentified complaints. At the mental component summary, the OT at the time of waking up and the peak OT in the HG were significantly higher than those in the LG. At the physical and mental component summary, lifestyle in the HG was more favorable. These data suggest that the daily rhythms of OT may reflect the mental health status of an individual. The entraining factors in circadian variation might play a role in improving mental health and reducing unidentified complaints. In conclusion, there appears to be an association between mental health status, lifestyle, and daily rhythms of OT.

EFFCT OF WALKING SPEED ON THE COMPLEXITY OF THE CYCLE OF HEAD FLUCTUATION DURING WALKING USING APPROXIMATE ENTROPY / 体力科学

The purpose of this study is to show clearly whether the complexity of the cycle of head fluctuation during walking is influenced with walking speed. Thirty young healthy males and females volunteered as subjects for this study. Subjects walked 40 m, and they were instructed to walk “slowly”, “a little slowly”, “usual speed”, “a little fast” and “fast” depending on their subjectivities. The head fluctuation of the right-and-left direction during a walk was measured by using an accelerometer. In addition, the complexity of the head fluctuation of the right-and-left direction cycle was calculated by utilizing Approximate Entropy (ApEn). After the value of ApEn was standardized at the walking speed, each walking speeds were compared. As a result, the value of ApEn increased at the slowly speed, and decreased with the increases in the walking speed. And the value of ApEn showed plateau or decrease at a little faster than free walking speed. From our results, it thought a possibility that Central Pattern Generator is optimized at the free walking speed. In conclusion, it is clear that walking speed have influenced on the complexity of the walking cycle.

EFFECTS OF SUPINE FLOATING ON RECTAL TEMPERATURE AND CARDIAC AUTONOMIC NERVOUS SYSTEM ACTIVITY AFTER HIGH AND MODERATE INTENSITY EXERCISE WITH A CYCLE ERGOMETER / 体力科学

The purpose of this study was to determine the effects of supine floating on rectal temperature and cardiac autonomic nervous system activity after exercise. Seven healthy males volunteered for this study. Subjects performed supine position for 30 minutes in both control condition (C-condition) and water condition (W-condition) after exercise with a cycle ergometer for 15 minutes. Exercise intensity was high (80%VO₂max) and moderate (60%VO₂max). Water temperature was 30 degrees Celsius. Rectal temperature of post exercise showed no significant differences under the W-condition, as compared to the C-condition. Delta rectal temperature (point 0-0 was end of exercise) was significantly reduced (p<0.05) under the W-condition, as compared to the C-condition. Log HF was significantly increased (p<0.05) under the W-condition, as compared to the C-condition. These data suggested that supine floating after high and moderate intensity exercise could promote recovery of rectal temperature and increased in cardiac parasympathetic nervous system activity.

Effects of Water Immersion on Systemic Cardiovascular Responses During Recovery Period Following Steady State Land Exercise / 体力科学

The aim of this studv was to clarify the effects of water immersion on the cardiovascular recovery process following submaximal steady state exercise on land. Seven male subjects (23 yrs old) underwent experiments under four separate conditions on separate days (15 minutes of cycling exercise at 50% and 80% maximal oxygen consumption followed by 16 minutes of recovery in a sitting position in water and out of water) . Concerning conditions in water, mean water temperature was 29.4 degrees, and the immersion level was set at xiphoid. Mean room temperature in out of water conditions, and during all conditions of exercise, was 24.4 degrees. Oxygen consumption (VO<SUB>2</SUB>), heart rate (HR) and blood pressure (systolic: SBP, diastolic: DBP) were measured under each condi tion. Mean blood pressure was calculated from SBP and DBP (MBP=1/3× ( SBP-DBP) +DBP) . Stroke volume (SV) was measured by Doppler echocardiography, and then cardiac output (CO=SV×HR), total peripheral resistance (TPR=NIBP/CO) and arteriaVmixed venous oxygen difference (a-v O<SUB>2</SUB>diff=VO<SUB>2</SUB>/CO) were calculated. In comparison with the same exercise intensity condition, there were no significant differences between recovery processes of VO<SUB>2</SUB>, HR, SBP, DBP and MBP in and out of water. SV and CO were significantly higher (p<0.05) during the recovery process in water than out of water (SV: at 50 and 80% maximal oxygen consumption conditions, CO: at 80% condition) . The TPR and a-v O<SUB>2</SUB>diff were significantly lower (p<0.05) during the recovery process in water than out of water at 80% oxygen consumption condition. These results indicate that water immersion facilitates circulating blood volume during the recovery process without increasing blood pressure, especially during recovery after high intensity exercise. Therefore, we suggest that increased left ventricular preload with immersion would be an important factor in cardiovascular regulation not only at rest but also during recovery after exercise.

Effect of Different frequencies of Skipping Rope on Elastic Components of Muscle and Tendon in Human Triceps Surae / 体力科学

The purpose of this study was to clarify the effects of different frequencies of skipping rope on the elastic components of muscle and tendon in human triceps surae. Six male subjects performed ten rounds of skipping rope. Skipping tempos were with in a range of 100-170 skips per minute (SPM) . The vertical ground reaction force and the surface EMG of triceps surae muscles were recorded during each skipping round. Elastic components of muscle and tendon were estimated by Residual Time (RT : lag time difference between the vanishing point of muscle discharge and disappearance of EMG, and the end of the ground reaction force wave) and RTintegrate (integration of ground reaction force while RT still appears) . RT and RTintegrate at 100 SPM were the smallest values for all jump frequencies. On the other hand, integrated EMG (iEMG) at 100 SPM was the largest value for all jump frequencies. Although RT and RT<SUB>integrate</SUB>progressively increased as SPM was increased, iEMG correspondingly decreased. Rate in utilization of elastic components of muscle and tendon assessed by RT<SUB>integrate</SUB>at 170 SPM corresponds to 150% at 100 SPM. These results suggest that the rate in utilization of the elastic components of muscle and tendon while skipping rope, depend on jump frequency.

The relationship between resting bradycardia with endurance training and autonomic nervous system modulation / 体力科学

We investigated whether the autonomic nervous system (ANS) modulation contribute to the bradycardia induced by endurance training. First, the meta-analysis approach was used to collect group mean values of maximal oxygen consumption (Vo<SUB>2</SUB>max) and heart rate variability (HRV) from 14 studies involving 30 groups and 485 subjects. Subsequently, we performed a cross-sectional (n=116) and intervention (n=training group : 10 and control group : 6) studies. In both studies, ANS modulation was estimated by spectral analysis of HRV. In the meta-analysis and cross-sectional study, HR and natural logarithmic high frequency power (In HF power) were correlated with Vo<SUB>2</SUB>max or peak oxygen uptake (peak Vo<SUB>2</SUB>) . The significant negative correlations were found between HR and In HF power (meta-analysis and the cross-sectional study ; r<SUP>2</SUP> = 0.42 and 0.44, respectively) . Endurance training in the intervention study increased peak Vo<SUB>2</SUB> and resting In HF power, and decreased resting HR. These results strongly suggest that endurance training induces an increase in resting ANS modulation especially parasympathetic modulation. Furthermore, about half of the variability of resting HR can be accounted for by difference in parasympathetic modulation.

Stress in the Lower Extremities Due to Walking Stairs One Step at a Time / 体力科学

The purpose of this study was to determine the differences between walking stairs one step at a time versus using alternating feet by evaluating muscle tensions and joint forces. This quantitative basic knowledge will be useful in setting safe guidelines for stair walking in rehabilitation programs. Five healthy young males participated as subjects. Ascending and descending motions were measured by utilizing a 3 D motion analysis system, a force platform and an EMG telemetry system. Measurements were made for three conditions : 1) Both limbs during alternating feet walking (normal stair walking : NW), 2) The leading limb (LL) and 3) The trailing limb (TL) when walking stairs one step at a time. Moments of force on the joints, muscle tensions and joint forces were calcu-lated using two mathematical models (the link segment and musculoskeletal models, Yamazaki (1992) ) . When ascending, maximum flexion angles of three joints in the TL were smaller than during NW. Also, quadriceps tension in the TL and soleus tension in the LL were smaller than during NW. Except for joint force, which was directed toward the anterior of the tibia, knee joint forces in the TL were smaller than during NW. When descending, maximum flexion angles of the three joints of the LL were smaller than during NW. The quadriceps tension and the soleus tension in the LL were smaller than during NW. Knee joint forces in the LL were smaller than during NW. The results suggested that : 1) When ascending, if a patient has a failure in the system of knee extension, the unaffected side should be made the LL and the affected side the TL. Also, if there is a failure in the system of plantar flexion, the unaffected side should be the TL and the affected side the LL. 2) When descending, if there is a failure in one limb, the unaffected side should be the TL and the affected side the LL.

Effect of Interval Training for 12 Weeks on Diastolic Filling of Left Ventricle During Mild Exercise / 体力科学

To clarify the mechanism responsible for the increase in stroke volume (SV) due to training, we investigated the effects of interval training on the left ventricle using M-mode echocardiography. Six healthy male subjects volunteered to undergo 48 training sessions for 12 weeks (4 sessions· week<SUP>-1</SUP>) One session consisted of five periods of exercise of 3-min duration on a cycle ergometer at a power output of 100% maximal O<SUB>2</SUB> uptake (Vo<SUB>2</SUB>max), interspersed with 2-min recovery cycling at 50%Vo<SUB>2</SUB>max. The echocardiograms at rest and during mild exercise (100W) were recorded before and after the training. The interval training significantly increased Vo<SUB>2</SUB>max. Although there was no significant difference in SV at rest before and after the training, the training increased SV significantly during exercise. Before the training, there was a significant difference in left ventricular enddiastolic dimension (LVEDD) and left ventricular end-diastolic volume (LVEDV) at rest and during exercise. However, after the training, LVEDD and LVEDV during exercise were significantly larger than those at rest. These results suggest that interval training for 12 weeks increases diastolic filling (elasticity) of the left ventricle during exercise in healthy young men, partly contributing to the increase in SV due to the training.

A basic study for establishing a suitable exercise prescription with long distance walking. II / 体力科学

The present study was performed to investigate the effects of 120 km walking, 40 km a day for 3 successive days on the condition that taking rest and foods freely, upon physical functions for healthy male and female subjects. All measurements were enforced at postabsorptive state early in the morning for the 10 successive days including the days of walking. Blood pressure, heart rate, and body weight were measured every morning. Blood samplings enforced, too. Urine collections were enforced from first day to 7 th day. The results obtained were as follows;<BR>1) There were no changes in heart rate, blood pressure, and body weight, which were measured early in the morning, before and after 120 km walking.<BR>2) Serum GOT and GPT activities had little changes, while serum LDH, α-HBDH, and CK activities increased gradually after walking.<BR>3) Serum CK-MB activities, which indicate myocardial injury, increased after walking, on the contrary CK-MB/CK ratio decreased. It was suggested that effects of 120km walking to myocardium were rather than slight ones.<BR>4) In spite of the same sorce in which serum CK-MB and LDH-1 were resulted, both did'nt exhibit same patterns in serum.<BR>5) Serum lipids decreased gradually after walking.<BR>6) Urinary excretion of creatinine and uric acid increased after 120km walking especially.<BR>7) If it is allowed to take sufficient foods and rest, 120km walking, 40km a day for 3 successive days, would not result in such a physical stress over the following days.

CHANGES OF MUSCLE RELAXATION MANNER DURING GROWTH / 体力科学

Manner of muscular relaxation in elbow flexion was observed on the subjects aged from 7 to 22 years old. Relation between surface electromyogram of <I>m, biceps brachii</I> and mechanogram of elbow flexion were used for the parameters of muscular relaxation.<BR>Results were as follows: 1) At elder subjects, silence of surface electromyogram preceeded to the tension decrease. But discharge of surface electromyogram preceeded during muscular relaxation at younger subjects. 2) It could be observed the transient tension increase before muscular relaxation. The appearance rate of the transient tension increment increased as becoming elder.<BR>From above results, it could be considered that the inhibitibility of spinal alpha motoneuron pool did not yet developed for about 7 years old.

A BASIC STUDY FOR ESTABLISHING A SUITABLE PRESCRIPTION OF EXERCISE ON THE LONG DISTANCE WALKING / 体力科学

The present study was performed to investigate the effect of long distance walking upon physical functions for healthy male subjects. The first experiment was carried out in 1977, the second, in 1978, and the third, in 1979 in each autum season. At the first experiment, subjects began walking upon having breakfast, then ate and drank noting during first 30km, and took some foods during another 26km. Twelve hours and fifty minutes of time was spent for 56km walking including 15, 60, and 30 minutes rest periods in between. In the second experiment, subjects ate nothing after dinner of the previous evening and 35km walking took 6 hours during which some rest periods were taken for blood sampling. The third was 80km walking for two days. Subjects walked 40km in 8 hours in the first day and on the following day they walked 40km in ten hours and twenty minutes. They took foods and rest freely.<BR>From the view points of the changes in blood and urinary recordings obtained from those three experiments, the influences of long distance walking on the body indicate as follows ;<BR>1) In case of long distance walking while nothing to eat and drink, the rate of serum saturated fatty acids composition decreased and unsaturated fatty acids increased.<BR>2) In a fasting state, blood glucose gradually decreased, LDH activity increased and blood lactate, GOT and GPT activity presented no significant changes on long distance walking.<BR>3) It was shown that the longer distance to walk, the lesser tendency in blood triglyceride even though subjects take a carbohydrate rich diet while walking.<BR>4) In fasting state, less than 35km walking without foods, the stress to the body seemed not to be critical.<BR>5) More than 40km walking in a day, even though taking meals, would result a significantly severe stress for body.<BR>6) As long as usual meals are taken, 80km walking for two days continuously, 40km in each day, would not result in such a physical stress over the following days.

EFFECT OF TAURIN ON THE METABOLISM WITH EXERCISE (I) / 体力科学

Effects of 20km running uppn taking a low-carbohydrate, high-fat and protein diet on the changes in blood pressure, heart rate, body weight, skinf old thickness, blood components and urinary recordings in five healthy young men were investigated and the changes in these items which occured by taurine inducement were studied by double blind test method. The results were as follows:<BR>1) As to the degree of decrease in body weight in 20km running, the case in taurine administration (T. A.) was more than in placebo administration (P. A.) .<BR>2) As to the degree of increase in systolic pressure upon 20km running, T. A. was less than P. A. 3) The rate of creatine kinase isozyme (CK-MB) against creatine kinase (CK), which increased after 20km running in P. A., was possible to reduce by T. A.<BR>4) T. A. was less than P.A. in the rate of increase in lactate dehydrogenase (LDH) on 20km running.<BR>5) In P. A., triglyceride increased after 20km running, but in T. A., it decreased.<BR>6) T. A, much influenced the rate of individual fatty acid composition on 20km running<BR>7) T. A, was more than P. A. in the secretion of adrenaline on 20km running.<BR>8) No changes were observed in other blood components and urinary kallikrein.