• The Korean Journal of Physiology
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• v.1 no.1
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• pp.103-120
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• 1967

As pointed out by many previous investigators, the cardio-pulmonary system of well trained athletes is so adapted that they can perform a given physical exercise more efficiently as compared to non-trained persons. However, the time course of the development of these cardio-pulmonary adaptations has not been extensively studied in the past. Although the development of these training effects is undoubtedly related to the magnitude of an exercise load which is repeatedly given, it would be practical if one could maintain a good physical fitness with a minimal daily exercise. Hence, the present investigation was undertaken to study the time course of the development of cardio-pulmonary adaptations while a group of non-athletes was subjected to a daily 6 to 10 minutes running exercise for a period of 4 weeks. Six healthy male medical students (22 to 24 years old) were randomly selected as experimental subjects, and were equally divided into two groups (A and B). Both groups were subjected to the same daily running exercise (approximately 1,000 kg-m). 6 days a week for 4 weeks, but the rate of exercise was such that the group A ran on treadmill with 8.6% grade for 10 min daily at a speed of 127 m/min while the group B ran for 6 min at a speed of 200 m/min. In order to assess the effects of these physical trainings on the cardio-pulmonary system, the minute volume, the $O_2$ consumption, the $CO_2$ output and the heart rate were determined weekly while the subject was engaged in a given running exercise on treadmill (8.6% grade and 127 m/min) for a period of 5 min. In addition, the arterial blood pressure, the cardiac output, the acid-base state of arterial blood and the gas composition of arterial blood were also determined every other week in 4 subjects (2 from each group) while they were engaged in exercise on a bicycle ergometer at a rate of approximately 900 kg m/min until exhaustion. The maximal work capacity was also determined by asking the subject to engage in exercise on treadmill and ergometer until exhaustion. For the measurement of minute volume, the expired gas was collected in a Douglas bag. The $O_2$ consumption and the $CO_2$ output were subsequently computed by analysing the expired gas with a Scholander micro gas analyzer. The heart rate was calculated from the R-R interval of ECG tracings recorded by an Offner RS Dynograph. A 19 gauge Cournand needle was inserted into a brachial artery, through which arterial blood samples were taken. A Statham $P_{23}AA$ pressure transducer and a PR-7 Research Recorder were used for recording instantaneous arterial pressure. The cardiac output was measured by indicator (Cardiogreen) dilution method. The results may be summarized as follows: (1) The maximal running time on treadmill increased linearly during the 4 week training period at the end of which it increased by 2.8 to 4.6 times. In general, an increase in the maximal running time was greater when the speed was fixed at a level at which the subject was trained. The mammal exercise time on bicycle ergometer also increased linearly during the training period. (2) In carrying out a given running exercise on treadmill (8.6%grade, 127 m/min), the following changes in cardio·pulmonary functions were observed during the training period: (a) The minute volume as well as the $O_2$ consumption during steady state exercise tended to decrease progressively and showed significant reductions after 3 weeks of training. (b) The $CO_2$ production during steady state exercise showed a significant reduction within 1 week of training. (c) The heart rate during steady state exercise tended to decrease progressively and showed a significant reduction after 2 weeks of training. The reduction of heart rate following a given exercise tended to become faster by training and showed a significant change after 3 weeks. Although the resting heart rate also tended to decrease by training, no significant change was observed. (3) In rallying out a given exercise (900 kg-m/min) on a bicycle ergometer, the following change in cardio-vascular functions were observed during the training period: (3) The systolic blood pressure during steady state exercise was not affected while the diastolic blood Pressure was significantly lowered after 4 weeks of training. The resting diastolic pressure was also significantly lowered by the end of 4 weeks. (b) The cardiac output and the stroke volume during steady state exercise increased maximally within 2 weeks of training. However, the resting cardiac output was not altered while the resting stroke volume tended to increase somewhat by training. (c) The total peripheral resistance during steady state exercise was greatly lowered within 2 weeks of training. The mean circulation time during exorcise was also considerably shortened while the left heart work output during exercise increased significantly within 2 weeks. However, these functions_at rest were not altered by training. (d) Although both pH, $P_{co2}\;and\;(HCO_3-)$ of arterial plasma decreased during exercise, the magnitude of reductions became less by training. On the other hand, the $O_2$ content of arterial blood decreased during exercise before training while it tended to increase slightly after training. There was no significant alteration in these values at rest. These results indicate that cardio-pulmonary adaptations to physical training can be acquired by subjecting non-athletes to brief daily exercise routine for certain period of time. Although the time of appearance of various adaptive phenomena is not identical, it may be stated that one has to engage in daily exercise routine for at least 2 weeks for the development of significant adaptive changes.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.3 s.28
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• pp.285-294
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• 1988

The purpose of this study is to investigate the effect of cotten, polyester and cotton/polyester blend fabrics on subjective wear sensations and physiological responses at the environmental conditions. Experimental garments were round neckline T-shirts made of $100\%$ cotton, $50/50\%$ cotton/polyester, $35/65\%$ cotton/polyester and $100\%$ polyester, respectively. Four healthy young women wern chosen as subjects for the experiment and the subjects have taken intermittent exercise for 30-min, on bicycle ergometer. Conditions of experimental chamber were as follows Environment I; Temperature $30\pm1^{\circ}C$, Humidity $70\pm3\%$ R.H and Air Velocity 0.25 m/sec Envorpnment II; Temperature $22\pm1^{\circ}C$, Humidity $54\pm3\%$ R.H. and Air Velocity 0.25 m/sec The results are as follows; 1) At Environment I, skin temperatures of chest and back covered with experimental garments were not significantly different, but, at Environment II, $100\%$ polyester garment showed the higher skin temperature. 2) In both conditions, garment made of $50/50\%$ cotton/polyester were felt the best 'tactile sensation' and 'comfort' 3) The significance of subjetive wear sonsations among clothings are larger in Environment I than in Environment II.

• The Journal of Korean Physical Therapy
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• v.14 no.2
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• pp.172-180
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• 2002

The purpose of this paper was to make an analysis of anaerobic power in professional female basketball players using the Wingate Test Method with bicycle ergometer. Twenty-three subjects(age $21.6\pm2.8years$, body height $178.0\pm7.4cm$, body weight $70.3\pm7.4kg$) were selected from professional female basketball team whose careers were over 10years and participated in this investigation. Each subject peformed a Wingate anaerobic power test to determine total work, peak power, mean power, fatigue index and blood lactate concentration. The following were obtained from result data analysis; 1. The Total Work of athletes was a $1128.7\pm120.6watt$ 2. The Peak Power of athletes was a $449.5\pm53.1watt$ 3. The Mean Power of athletes was a $369.1\pm39.4watt$ 4. The Fatigue Index of athletes was a $33.5\pm6.9\%$ 5. The blood lactate concentration was $1.85\pm0.85mM/L$ at the normal state and $3.16\pm1.53mM/L$ at the after Wingate test. The blood lactate concentration was $6.96\pm0.81mM/L$ after 3 minute and $6.95\pm1.05mM/L$ after 5 minutes.

• Journal of Nutrition and Health
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• v.27 no.2
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• pp.162-171
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• 1994

The purpose of this study was to describe the effects of caffeine ingestion on the metabolic responses during submaximal exercise. Ten male of rowing player aged 18-22yrs. participated in the study. No subjects had any remarkable medical history and none were taking medications. According to the administration of dehydrated caffeine(CA) (6mg/kg) or placebo(PA), they were classified into two groups such as caffeine group and placebo group. A randomized, double-blind, crossover protocol was employed using either CA or PA. Subjects underwent a submaximal bicycle ergometer. Blood was drawn intravenously prior to 60 min., at rest, at 30, and 45 min. of exercise, and recovery period. Plasma concentrations of glucose, free fatty acid and lactate were obtained using enzymatic method. Followings were obtained by the tests and analyses; 1) Blood glucose(BG) of 45 minute of exercise was significantly decreased in CA group of 76.3$\pm$14.8 mg/100ml compared with PA group of 94.9$\pm$11.2 mg/100mg(p<0.5). 2) Free fatty acid(FFA) of 30minute of exercise was significantly increased in CA group of 720$\pm$80 $\mu$Eq/1 compared with PA group of 360$\pm$120 $\mu$Eq/1(p<0.5). After exercise, FFA was significantly higher in CA group than those in PA group(p<0.1). 3) Blood lactate(BL) was not significantly different between the two. After exercise, BL was significantly different in 30 minute(p<05).

• Journal of the Korean Society of Clothing and Textiles
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• v.11 no.3 s.25
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• pp.41-55
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• 1987

The purpose of this study is to investigate the effects of napping of knitted fabric on wear sensation and physiological responses. Experimental garments were four types of warm-ups made of either $100\%$ PET or $65/35\%$ P /C and either napped or unnapped respectively. Two healthy young female adults were chosen as subjects for the experiment. Experimental room conditions were as follows: Temp., $22\pm0.5^{\circ}C$ R.H., $54\pm3\%$ and Air Velocity, 0.25m/ sec or 2. 86m/sec. The subjects exercised on bicycle ergometer and rested alternatively for totally 45-min. The results are summarized as follows. 1) With napped Warm-up, chest, back, mean skin temp. and microclimates, i.e., temp., relative humidity and water vapor pressure inside the clothing, were higher than with unnapped warm-up. And there was no difference in pulse rate between napped and unnapped warm-ups. 2) Wear sensations of thermal, humidity, tactile and comfort were 'more hot' and 'more uncomfortable' in 0.25m/sec air velocity. but in 2.86m/sec condition the tactile sensation was 'better' and 'more comfortable' with napped warm-ups. According to Pearson's Correlation, among various kinds of wear sensations, tactile is most related with comfort. From these results, it can be concluded that napped fabric decreases the rate of heat trans? mission and moisture diffusion through the clothing. Therefore skin and body temp. and temp., R.H., Vapor Pressure inside the clothing are increased.

• Journal of Biomedical Engineering Research
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• v.3 no.1
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• pp.23-30
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• 1982

The regimen of physical activity of the patient with coronary artery disease requires that he should not overshoot the prescribed heart rate based on his age, health and fuctional status of the heart during his exercise. The step input of work load, however, involves a great danger of overshooting. The purpose of this study was to desigil a system that makes it passible for a subject to check the overshooting. This system shows on tile H.R-meter, the amplified and filtered heart-rate signal of the subject received by the photosensor on his earlobe, puts it in the lead coinpensational circuit where it is conpared with the reference input signal(=the presfribed heart rate). The output of the lead compensational circuit works the aull meter. By means of this null meter, the subject knows whether he is overshooting the prescribed heart rate or not. He can continue the natl meter needle at the'Zero'position through the control of the speed of pedaling of the bicycle ergometer, An experimental test, made on eight men and four women in healthy condition, showed that 91. 7% of them vlaintained the stable heart rate and that the overshooting of the desired heart rate did not exceed $\pm$2BPM. According to the result of this experiment, since the heart rate feedback controller makes it possible for the subject to take the prescribed exercise based not on the work load but on the heart rate which incidentally is inexpensive, it can be made use of as the instrument for the regimen of pflysical activity by the patient with coronary artery disease.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.8 no.3
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• pp.293-301
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• 2001

Purpose: The purpose of this study was to investigate the effect of exercise therapy and relaxation therapy on the level of ACTH and cortisol in workers and to determine, from this information, the effectiveness of applied exercise therapy and relaxation therapy as a nursing intervention method for workers experiencing stress. Method: The subjects were divided into an exercise therapy group. a relaxation therapy group, and a control group. The research design was a nonequivalent control group pretest-posttest design (exercise therapy : n=12. relaxation therapy: n=12, control group, the group without exercise or relaxation therapy: n= 12). The subjects in the exercise therapy group were given a particular intensity for each kp over 30 min, bicycle ergometer which uses the LX PE training system before and after four weeks of training. The subjects did 60-70% exercise intensity exercise therapy for eight weeks The relaxation therapy subjects were trained using a modified Jacobson's relaxation technique for eight weeks. The exercise and relaxation therapy groups were trained at the following intensity for eight weeks (3 times/week, 30 min/day). Changes in the levels of ACTH and cortisol were identified. Two-way ANOVA and multiple range test (SNK: Student Newman Keul) were used to examine the effects of exercise therapy and relaxation therapy at four and eight weeks. Result: 1. Changes in the level of ACTH in the relaxation therapy group were statistically significant at .05 level, and were better than that of the exercise therapy group after eight weeks. But there was no significant difference between the exercise therapy group and the control group. 2. Change in the level of cortisol in the relaxation therapy group were statistically significant at .05 level as compared to the exercise therapy group and the control group after four weeks, but not after eight weeks. Also, the relaxation therapy was statistically significant at .05 level after four weeks compared to before treatment, but there was a tendency toward increased cortisol after eight weeks. Conclusion: Relaxation therapy was found to be more effective in stress treatment than exercise therapy and as such is a desirable nursing intervention method for stress hormone reduction in workers.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.2
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• pp.183-192
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• 2006

Predicting energy expenditure (EE) is important to prevent work-related musculoskeletal disorders (WMSDs). The problem to predict EE is that the standard of EE is based on western data. The authors checked average EE by job categories to provide basic data for suggesting proper work intensity for Korean workers. This study was conducted from 2003 to 2005. Study subjects were recruited from 4 car parts assembly plant, 2 car assembly plant, 2 Heavy machine manufacturing plant and 2 shipyards. Total study subjects were 515 male workers. To estimate VO2max, sub-maximal test was conducted to measure VO275%max by bicycle ergometer (Combi Co, Aerobike 75XL II). Heartbeats were recorded with heartbeat recorder (Polar Electro Co, Finland, S810) during work. EE of work was calculated by recorded heartbeat and individual regression equation which was derived from sub-maximal test. Subjects were classified into 4 industry and 8 work posture, 23 job task categories. Mean EEs (S.D.) according to industry classification (kcal/min) were 4.9 (0.7), 4.8 (0.7), 4.9 (0.7), 5.0 (0.9), and 4.0 (0.5) for Car Part manufacture, Car Assembly, Ship Building, Heavy Machinery Manufacture, and Hospital Office, respectively. The results suggest that Korean male workers of exceeding to the NIOSH criteria will be needed to plan for job rescheduling to maintain $worker^{\circ}$Øs health. Further study to establish Korean work intensity standard would be needed.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.3
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• pp.356-362
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• 1999

Humans may lose considerable amounts of water and electrolytes from sweat during exercise in a hot climate. Optimal ingestion of fluid-replacement beverages may overcome an obstacle factor of exercise performance in the heat. This study was performed the comparison of heart rate and blood lactate between ingestion of Prunus mume solution and water solution during graded maximal exercise using bicycle ergometer in the heat(ambient temperature of 31-32$^{\circ}C$ and relative humidity of 50-55%). Ten healthy no-heat-acclimatized males participated in the study. Exercise duration until all-out of graded testing in the condition of Prunus mume solution ingestion(786.15$\pm$47.66s) was significantly higher(P＜0.05) than the condition of water ingestion. Heart rate at 4 min during graded testing and recovery phase in the condition of Prunus mume solution ingestion was significantly lower(P＜0.05) than the condition of water ingestion. Blood lactate concentration at 30min of recovery phase after graded maximal exercise in the condition of Prunus mume solution ingestion was significantly lower(P＜0.05) than the condition of water ingestion. Recovery rate of blood lactate concentration at 15 min and 30 min of recovery phase after grated maximal exercise in the condition of Prunus mume solution ingestion was significantly lower(P＜0.05) than the condition of water ingestion. Present results suggested that ingestion of Prunus mume solution showed the positive effects on the cardiorespiratory function and acid-base regulation as compared with ingestion of water during graded maximal exercise and recovery phase in hot environment.

• Journal of Korean Biological Nursing Science
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• v.3 no.1
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• pp.29-40
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• 2001

The purpose of this study was to investigate the effect of exercise training on work capacity, psychologic functions and quality of life in hemodialysis patients. Forteen hemodialysis patients, 3 males, 11 females, age ranged from $23{\sim}58$ years($42.3{\pm}0.4$) were selected and assessed using a modified Bruce protocol on a treadmill. The 3 months supervised exercise training consisted of 60 minites session thrice weekly on the treadmill, bicycle and arm ergometer at $40{\sim}60%$ of maximum $O_2$ consumption. The changes of maximum $O_2$ consumption, psychologic test and quality of life questionnaire in 14 patients before and after 3 months exercise training have been measured. The mean maximum $O_2$ consumption($VO_2$ max) of exercises increased by 23% after training(pre-and postexercise $26.3{\pm}4.6ml$/kg/min vs $29.8{\pm}4.9ml$/kg/min, p=0.013). There was significant reduction in anxiety score(p=0.004) and significant improvement in quality of life score(p=0.031) after training. The result of this study indicated that a structured exercise training for hemodialysis patients provides many benefits. These result suggest the exercise training can improve the work capacity, psychologic functions and quality of life outcomes in hemodialysis patients.