The purpose of the present study was to elucidate the effective recovery mode during intervals in water-polo games from the viewpoint of blood lactate removal. Six male elite water-polo players (aged 20±2 years old) volunteered to participate as the subjects. Three different modes of recovery ; sitting (Rest), kicking of breast stroke on the spot (Kick), and backstroke swimming (Swim) were compared for breathing air or 60%O₂. Blood lactate removal was expressed as the percentage decrease in blood lactate concentration from the end of preceding period to the end of the interval. The lactate removal in Swim was the highest (p<0.05) of the three kinds of recovery modes. Lactate removal indicated a higher value in order of Swim>Kick>Rest for breathing air. And it was facili tated in Swim (2.1%), Kick (5.4%) and Rest (8.1%) by 60%O₂ inhalation, although no significant differences were observed. From these results, it was suggested that the blood lactate removal during intervals in water-polo games would be facilitated by an active recovery mode like Swim, and that the inhalation of 60%O₂ would not bring any significant effects.

View full abstract

The purpose of the present study was to compare between healthy male endurance trained athletes (T, n=6) and sedentary control subjects (S, n=6) for the blood velocity profile in left ventricle at rest and during exercise. Peak velocity of blood injection into the left ventricle at diastole (dV), peak velocity of blood ejection out of the left ventricle at systole (sV), duration of blood injection (dD) and duration of blood ejection (sD) were measured by pulsed Doppler sonography at rest and during cyclic ergometer exercise at intensity of 40, 60 and 80% maximal 0₂ uptake (VO₂max) . The dV tended to be higher T than S at rest and during exercise at all intensities, and statistical significance existed at rest and during exercise at 80%VO₂max. However, there was no significant differences in the sV between T and S. In addition, the dV/sV in T was significantly highter than that in S at rest and during exercise at all intensities. These results indicate that Pulling velocity on the left ventricle in T was faster than that in S. In other words, these indicate that preload on the left ventricle in T was larger than that in S. Moreover, the relationship between stroke volume and dV (r=0.50, p<0.001) was closer than that between stroke volume and sV (r=0.30) in all subjects at rest and during exercise. These data suggest that the contribution of enhanced dV was stronger than that of sV to the larger stroke volume observed in dV.

View full abstract

A training experiment was carried out to investigate the difference in training effects between power-up type and bulk-up type strength training exercises from the aspects of muscle histochemical properties and capillary supply. The subjects were eleven healthy males. The power-up type group (five males) performed knee extension exercise for 5 sets at 90% of 1 RM (one repetition maximum) with a 3-min rest between sets (repetition method) . The bulk-up type group (six males) performed the same exercise for 9 sets at 80-40% of 1RM with a 30-s or 3-min rest between sets (interval method, multi-poundage system) . Both programs were carried out twice a week for 8 weeks.
The main results were as follows ;
1. Percentages of fiber types showed no recognizable changes in either group.
2. Fiber area was significantly increased for all fiber types (Type I, Type IIA, Type JIB) in both groups. However, the rate of increase was greatest for type IIA fiber, followed by type JIB fiber and then type I fiber. Moreover, the rate of increase for all fiber types in the bulk-up group was higher than that in the power-up group.
3. Percentage of fiber area showed no recognizable changes for any fiber types in the powerup group. However, the percentage area of type II fibers, especially type IIB fiber, was significantly decreased in the bulk-up group.
4. CC (Type I), CC (Type IIA) and CC (Type IIB) (number of capillaries in contact with each fiber type) were significantly increased in both groups. However, in comparison with CC (Type I), CC (Type IIA · Type IIB) showed a higher rate of increase in the power-up group. On the other hand, in comparison with CC (Type IIA · Type JIB), CC (Type I) showed a higher rate of increase in the bulk-up group. Also, compared with the power-up group, the bulk-up group showed a signifi-cantly higher rate of increase of CC (Type I) .
5. C/Fiber area (Type I), C/Fiber area (Type IIA) and C/Fiber area (Type IIB) (number of capillaries supplying each fiber area) were decreased in both groups.
The above results show that power-up type exercise leads mainly to hypertrophy of type I, type IIA and type IIB fibers without any change in percentage fiber type or percentage fiber area, whereas bulk-up type exercise leads mainly to hypertrophy of each fiber type with decreases in percentage area of type II fibers, especially type JIB fiber. Also, power-up type exercise leads mainly to an increase in the number of capillaries around type II fibers, whereas bulk-up type exercise leads mainly to an increase in the number of capillaries around type I fiber. However, capillary development around all fiber types did not necessary coincide with muscle hypertrophy in either exercise.
The authors reported previously that power-up type exercise is effective mainly for improving muscular strength and anaerobic power, whereas bulk-up type exercise is effective mainly for induc. ing hypertrophy and anaerobic endurance. The results of this study may help to clarify these effects from the viewpoint of the adaptations of muscle fibers and the capillary supply.

View full abstract

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

View full abstract

A study was conducted to examine the effects of exhaustive enduring exercise training on the skeletal muscle of rats. Twenty-six male Wistar rats were divided into 3 groups : an exhaustive training group (EE), a free-eating control group (Co), and a pair weight group in which body weight was matched to EE (PW) . The rats in EE were forced to run on a treadmill with an inclination of 0-3°, 6 days/week for 4 weeks. At first the rats ran at a constant speed for 60 min. Then we gradually added 2 m/min to the basic speed every minute until they were exhausted. The treadmill speed was 20 m/min during the first, 30 m/min during the second, 35 m/min during the third, and 40 m/min during the final week. The muscle wet weight, the quantity of the muscle protein and the isometric tetanic force were measured with the soleus and extensor digitorum longus (EDL) . Food restriction induced significant decreases in EDL weight. Exhaustive enduring exercise training induced noteworthy decreases in soleus weight, but remarkable gains in EDL weight. It also induced significant changes of the quantity of the muscle protein in the two muscles, which corresponded to the changes in muscle weight. The isometric tetanic force of both muscles was not affected by food restriction. The isometric tetanic force showed a significant decreases in EDL in EE comparison Co. The isometric tetanic force of the soleus did not show a significant decreases. However, its degree of decrease corresponded to that of the muscle protein. These findings illustrate that exhaustive endurance exercise training induces degradation of the soleus and hypertrophy of the EDL. However, it also decrease the muscle force which generats the capacity of the two muscles. We think that this phenomenon depends on the skeletal muscle characteristics, such as fiber type, and eccentric or concentric contraction.

View full abstract

We examined the relationship between serum magnesium (sMg) change and urinary Mg (uMg) excretion, lipid metabolism and hormonal responses induced by prolonged physical exercise. Six recreational runners voluntary participated in the study, and their sMg, uMg, serum lipid and circulatory levels of plasma hormones (ACTH, cortisol, ADH, aldosterone) were determined during a 1-week recovery period after a full-marathon race. Immediately after the race, fall of sMg was significant, but recovered to the pre-race level in the next day. Urinary Mg excretion decreased significantly after the race and the tubular reabsorption rate (%TRMg) was elevated for one week. The negative correlation between sMg and %TRMg suggested that a decreased level of sMg enhanced tubular reabsorption of Mg. On the other hand, no correlation was observed between the plasma hormone levels and %TRMg, thus hormonal responses induced by prolonged exercise had less effect on the tubular reabsorption of Mg. Therefore, fall of sMg after the full marathon race may not be a reflection of Mg depletion, but seems to be the result of a Mg shift to other regions (muscle, erythrocytes and adipose cells) from the serum. Increased level of serum FFA after the race suggested enhanced lipolysis, which might be a cause of sMg reduction.

View full abstract

The purpose of this study was to investigate the relationships of fundamental physical fitness (FPF) and health-conditions, activities of daily living, and food habits in elderly women.
A total of 338 women aged 60 to 89 years were the subjects for this study. Fourteen tests were selected from 4 physical fitness domains of muscle function, joint function (flexibility), neuromuscular function and lung function, considering the validity, safety and convenience of tests. To measure the above-stated living conditions, a questionnaire consisting of 30 items was constructed. Principal component analysis was applied to the correlation matrix, which was calculated from physical fitness variables. The first principal component could be interpreted as the FPF factor, since it correlated significantly with all physical fitness variables and showed the greatest contribution (about 36%) to total variance. Statistical techniques of contingency coefficient and theory of quantification I were used to determine the influence of the above-stated living conditions to FPF.
It was inferred that each living condition influences FPF as a composite factor, and the elements of exercise habit, the existence of the trouble caused by past disease and injury, bedtime and age have greater influence on the decline of FPF. Fundamental physical fitness showed a decreasing trend with age, but the continuous exercise enforcement on one day or more a week, seemed to be effective in postponing the decline of FPF related to age. Further, it was inferred that influence of each living condition to FPF differs in the 60 and 70 age levels.

View full abstract

It is generally accepted that secretory immunoglobulin A (sIgA) is a major effector of local immunity in the oral cavity. The salivary sIgA level is known to be temporarily decreased after an acute single bout of intense exercise. On the other hand, the effect of continuous exercise training on salivary sIgA has been controversial. In the present study, we collected timed saliva samples from collegiate kendoists using the reliable saliva collection method that has already been reported. The collection was performed before, during and after a traditional high-intensity 10-day training camp during the coldest part of the winter. We investigated the effect of repetitious intense exercise training on resting sIgA levels in saliva.
The subjects were 19 males and 8 females (age: 19.9±0.5 years) who took part in the camp. We obtained saliva samples before the camp, on the first and the 10th days of the camp, and 4 and 10 days after the camp at 5 p. m. The concentration of sIgA was measured by ELISA, and the sIgA secretion rate was calculated.
The resting sIgA secretion rate decreased significantly during the camp. It remained at a lower level 4 and 10 days after the camp compared to the initial level, although it tended to recover gradually. Prolonged suppression of the resting sIgA secretion rate during a traditional winter kendo training camp might be induced by repetition of high-intensity training.

View full abstract