This study examined the physiological response to different water depths in recreational synchronized swimming. Nine middle-aged, female, recreational swimmers carried out the same team free routines in deep water (deep-water synchronized swimming: DWS) and shallow water (shallow-water synchronized swimming: SWS). Heart rate (HR) was measured continuously during each performance, combined with estimation of metabolic equivalent (MET) values using individual linear regression equations of HR-oxygen uptake. These equations were created using the results of 12 water activities. Blood lactate concentration and systolic blood pressure were measured at the 1/3 and 2/3 stages and immediately after each performance period. HR and estimated METs during DWS (mean±SD, 152.9±7.5 beats·min^-1 and 7.3±1.2) were significantly higher than those measured during SWS (131.8±11.3 beats·min^-1 and 5.7±0.8). Blood lactate concentration and systolic blood pressure measured immediately after DWS were significantly higher than those measured after SWS. With DWS, blood lactate concentration at the 2/3 stage and immediately after the performance were significantly higher than those measured at the 1/3 stage, whereas in SWS no significant difference was found in these values at any time period. In conclusion, the exercise intensity of DWS was high and SWS moderate. The predominant sources of energy may be phosphocreatine stores and aerobic metabolism during these performances. It is possible that glycolysis may also play an important role in energy requirements during the 2/3 stage and immediately after a DWS performance.

The effects of wind and rain on exercising humans have not been fully investigated in the field of sports science. The purpose of this study was to investigate the characteristics of thermoregulation and cardiovascular-respiratory responses during exercise in a climate chamber that allowed control of wind and rain. Seven healthy males performed treadmill running at 70%VO_2max for 30 min under three conditions (CON, control ; WIND, wind only; WIND&RAIN, both wind and rain). The temperature was 27.0℃ under the three conditions. Relative humidity was 60%RH except under the WIND&RAIN condition (100%RH under WIND&RAIN condition). The wind velocity corresponded to running velocity in the open air and the precipitation was 90 L/h. Under the WIND&RAIN condition, both body trunk and extremities skin temperature (T_sk) showed a clear decrease for the first 5 minutes after the start of running, and was significantly lower during the running period than under the other two conditions (p<0.05). Rectal temperature (T_re) did not differ significantly among the three conditions. An interaction was observed between conditions and time in terms of minute ventilation (VE) (p<0.05). Under WIND and WIND&RAIN conditions, VE was higher than under CON condition while running. Oxygen consumption, heart rate and respiratory exchange ratio did not differ significantly among the three conditions. These results indicate that wind and rain in a natural environmental condition with neutral temperature (27.0℃), cause a decline in T_sk, and may become factors that influence performance, similarly to temperature and humidity.

Six young males walked in a swimming pool, swimming flume and land treadmill at 0.4, 0.6 and 0.8 m·⋅^-1. At 0.6 and 0.8 m⋅s^-1, VO₂and HR values were significantly lower for the swimming flume walking than for the swimming pool waking. At rest and 0.4 m⋅s^-1, there were no significant VO₂differences between swimming flume walking and land treadmill walking ; while significantly lower HR values were found for swimming flume walking. There was no significant difference in the VO₂-HR relationship between land treadmill waking and swimming pool waking. On the other hand, a significant downward sift in the regression line was observed in swimming flume waking compared to land treadmill walking. The differences between the two types of underwater walking exercise may produce a different effect concerning the muscle pump on leg muscles. Soleus, and especially lateral gastrocnemius muscles, showed lower electromyogram activity at push-off phase during swimming flume walking compard with swimming pool walking. This activity may contribute to the lower VO₂and HR values during swimming flume walking. It is apparent that the swimming flume walking has different physiological and kinematic characteristics such leg muscles EMG activity walking or swimming pool walking.

This study was designed to analyze physiologically recreational synchronized swimming and speed swimming. Two types of recreational synchronized swimming (Long face-in time performance : LFIP and Short face-in time performance : SFIP) and maximum exertion in the 200-m free style swimming (200 mFR) were measured in six recreational middle-aged female swimmers. LFIP and SFIP were conducted in shallow water. The percentage of face-in time for LFIP was about 10% longer than that of SFIP. Heart rate (HR) during each exercise was measured continuously. Blood lactate concentration (La), the rate of perceived exertion (RPE) and systolic and diastolic blood pressure (SBP, DBP) were measured after each exercise. Average HR during the LFIP, SFIP and 200 mFR were 133±12, 132±13 and 153±12 beats·min^-1 (mean ± SD), respectively. La was 2.4±0.7 mmol·1^-1for LFIP, 2.2±0.6 mmol·1^-1for SFIP and 5.7 ± 2.4 mmol·1^-1for 200 mFR, respectively. SBP was 181±32 mmHg for LFIP, 166±22 mmHg for SFIP and 185±30 mmHg for 200 mFR, respectively. No significant differences were observed in blood pressure among the three exercises. SBP of 200 mmHg or higher after LFIP and 200 mFR was observed in some subjects. HR, La and RPE for LFIP and SFIP showed no significant differences, but were significantly lower than those of 200 mFR. These results show that the exercise intensity of LFIP was moderate and was similar to that of SFIP. LFIP, however, caused a marked rise in SBP. Thus, SFIP may be more recommended for health promotion to recreational middle-aged swimmers than LFIP.

Walking exercise in forests, referred to as “shinrin-yoku, forest-air bathing and walking, ” has been attracting attention as a method for promoting mental and physical health utilizing the environment and topography of forests in the recent time. Walking exercise in forests has characteristics arising from the natural environment and topography of forests with beautiful trees, twittering of birds, and favorable fragrances of woods, etc. However, scientific verification of such specific effects is necessary in order to make walking an authentic method to health promotion. This study intended to physiologically investigate it from physical and scientific point of view. For this purpose, we determined chronological changes in energy consumed in walking exercise in forests with a portable oxygen intake measuring device, on the basis of data on the respiratory and circulatory systems such as heart rate and the amounts of ventilation and oxygen intake. The results suggested that the changes in these parameters showed the movement correlated with the changes in topography of forests, including the inclination and demonstrated that selection on the resting locations was related to the comfortable rhythm of walking. Furthermore, it was indicated that exercise loading to living body tended to increase in association with increases in the upward inclination, resulting that the energy consumed in walking was less though the amounts of exercise loading to lower limbs tended to be very large at a download inclination of 36.0 degrees or larger. This demonstrative study suggested that to determine chronological changes in physiological loading conditions related to the walking route was effective to establish promenades in order to perform comfortable and effective forest bath.

A study was conducted to clarify the exercise intensity and metabolic condition during a free routine of synchronized swimming with respect to heart rate (HR), blood lactate concentration (La) and the rate of perceived exertion (RPE) . Six well trained female synchronized swimmers participated as subjects. HR during the free routine was measured continuously. La and RPE during the free routine were measured intermittently from the start to end of each stage. Maximum heart rate (swimmingHRmax : S-HRmax) was determined by measurement of maximum oxygen uptake using a swimming flume. Peak blood lactate concentration (Peak La) was measured after the maximum front crawl stroke of 100 m. The average values and S. D. of S-HRmax and Peak La were 180.0±3.8 beats · min^-1 and 9.6 ± 1.0 mmol · 1^-1, respectively. Average values, S. D. and ranges of HR and %S-HRmax during the free routine were 137.6±25.5 (60-180) beats · min^-1 and 76.5± 14.3 (34.5-96.8) %, respectively. HR during the free routine showed a decrease in the breath-holding phase. Average values and S. D. of La, %Peak La and RPE at the fourth stage were 5.4±1.2mmol·1^-1, 57.0±17.2% and 17.7±0.8, respectively. La, %Peak La and RPE at the fourth stage were significantly higher than those at the other stages, and La, %Peak La and RPE at the third stage were significantly higher than those at the second stage. These results suggested that the overall intensity of the free routine was moderate, but that part of the free routine included high-intensity activity and the percentage of anaerobic metabolism during the free routine increased in the final stages

The purpose of this study was to determine the physiological responses, stroke rate and stroke length of front crawl leg kick and arm stroke of age-group and college swimmers and to elucidate the characteristics of male age-group swimmers, which have not been highlighted adequately. The subjects were ten 11.8-to 12.4-year-old well-trained male elementary school swimmers (group E) and nine 20.1-to 21.1-year-old well-trained male college swimmers (group C) . All the subjects were categorized into similar swimming levels for their ages. All the experiments were performed in a swimming flume (AQUAGYM made by IHI) . The water velocities during leg kicking and arm stroking were 60 and 70%, respectively, of the maximal velocity at maximal oxygen uptake (Vmax) . The oxygen uptake (VO₂), heart rate (HR), pulmonary ventilation (V_E), tidal volume (TV), respiratory rate (RR) and blood lactate (BL) level of each group were significantly higher during leg kicking than arm stroking at both velocities. VO2, V_E; and TV were significantly higher in group C than group E during leg kicking and arm stroking at both velocities, but HR, RR and BL did not differ significantly. The leg kick to arm stroke VO₂ ratio at 70% Vmax was significantly higher in group E than group C. The stroke rate at the same velocity was significantly lower and the stroke length was significantly higher in group C than group E, but the kick rate and length did not differ significantly. VO₂·SR^-1 and VO₂ KR^-1 at both velocities were significantly higher in group C than group E. VO₂ Wt^-1 SR^-1 at 70% Vmax was significantly higher in group C than group E, but VO₂ Wt^-1 KR^-1 at both velocities was significantly lower in group C than group E. These results clarified the differences between group E and group C, which must be considered carefully when designing a training program for age-group swimmers.

The most characteristic feature of the triathlon is integration of the three endurance activities including of swimming, cycling and running, into a continuous task. So, it is necessary to identify the cardiorespiratory responses during the triathlon to develop a beneficial training program. Twelve male triathletes conducted a simulated triathlon test in a laboratory. This test consisted of continuous swimming, cycling and running using a flumepool, a bicycle ergometer and a treadmill, respectively. The exercise intensity and duration were 60% of maximal oxygen uptake during swimming, cycling and running for 30, 75 and 45 min, respectively. The results demonstrated that the residual effects of the prior exercise stage were observed during the latter exercise stage : The prior swimming stage produced an increment of oxygen uptake and heart rate during the cycling stage ; Prior swimming and cycling stages increased oxygen uptake, minute ventilation, heart rate and ventilatory equivalent to those during the running stage. These results suggest that the residual effects of the preceding exercise decreased the mechanical and respiratory efficiency by increasing the physiological demands of conducting the subsequent exercise. Therefore, triathletes are recommended to train themselves in a continuous task rather than separately.

This study was designed to determine prediction equations of body density (BD) for athletes using anthropometric variables and to examine validity of the prediction equations. The subjects were 211 male and 198 female athletes aged 18 to 22 years. The subjects were measured for standing height, body weight, skinfold thickness, girth as well as body composition. Body composition was estimated from densitometry using underwater weighing method and pulmonary residual volume measurement. Skinfold thickness was measured at 9 sites on the right side of the body with an Eiken-type ski nfold caliper and 7 measures of girth were taken using a cloth tape. All measurements were done three times from April to October : pre-, mid- and post-competitive season, in order to find out a suitable site reflecting body composition change. Using multiple regression analysis, equations to estimate BD were obtained from standing height, body weight, skinfold thicknesses and girths. The effective prediction equations for BD were as follows : For Males
ED=1.11104-0.00053 (sum of chest, abdomen and quadriceps skinfold thicknesses in mm) -0.00027 (waist girth in cm) .
R=0.851, SEE=0.0051.
For Females
BD=1.11861-0.00054 (sum of abdomen, triceps and subscapula skinfold thicknesses in mm) -0.00054 (waist girth in cm) .
R=0.826, SEE=0.0062.
A cross-validation analysis of these prediction equations for BD correlated highly with hydrodensitometrically determined BD (r=0.832, SEE=0.0053 for males and r=0.812, SEE= 0.0062 for females) . Thus the prediction equations developed in the present study will be applicable to athletes.

This study was designed to find out about the body composition of ordinary Japanese adults, and to clarify how gender and age have effects on it. The subjects were volunteers living in the northern, central and western parts of Japan. They consisted of 154 males and 142 females aged 20 to 59 years. Their body height and weight did not differ by more than 1 S. D. from the mean of the given age category cited in the Japanese Ministry of Education Annual Report. Body composition was estimated from densitometry using an underwater weighing method and pulmonary residual volume measurement. Within each age group, there were significant differences in body height, weight, body density, percentage body fat, lean body weight, fat per 1 m of body height and lean body weight per 1 m of body height, but there was no significant difference in fat between males and females. Percentage body fat and fat increased significantly with age in both genders. The rate of increases of fat were calculated to be 14.2% for males and 10.7% for females per decade. Lean body weight decreased significantly with age in males, decreasing at a rate of 3.3%. However, the lean body weight of females stayed constant over the given ages of this study. These results show that the difference in body weight between males and females is caused by lean body mass, not by fat.