The purpose of this study is to investigate the effect of the long-term aerobic exercises on cardiac structure, left ventricular stroke volume, and cardiac output. To achieve the purpose of the study, a total of 22 volunteers—including 10 people who have continued regular exercises and 12 people as the control group—were selected as subjects. With regard to data processing, the IBM SPSS Statistics ver. 21.0 was used to calculate the mean and standard deviation, and the difference of the means between the groups was verified through an independent t-test. As a result, there were significant differences between groups in the left ventricular end-diastolic internal dimension, left ventricular end-systolic internal dimension, left ventricular end-diastolic septum thickness. There were significant differences between groups in left ventricular end-diastolic volume, left ventricular mass, and left ventricular mass index per body surface area. However, in cardiac function, only left ventricular stroke volume showed a significant difference between groups.

The purpose of this study is to investigate the effects of strenuous exercises on resting heart rate, blood pressure, and maximal oxygen uptake. To achieve the purpose of the study, a total of 30 subjects were selected, including 15 people who performed continued regular exercises and 15 people as the control group. With regard to data processing, the IBM SPSS Statistics ver. 21.0 was used to calculate the mean and standard deviation. The difference of mean change between groups was verified through an independent t-test. As a result, there were significant differences in resting heart rate, maximal heart rate, maximal systolic blood pressure, and maximal oxygen uptake. However, the maximal systolic blood pressure was found to be an exercise-induced high blood pressure. Thus, it is thought that a risk diagnosis for it through a regular exercise stress test is necessary.

The purpose of this study was to investigate the effects of aquatic exercise on body composition, physical fitness, and vascular compliance of obese elementary school students. For the purpose of this study, 20 obese elementary students were selected as subjects. The subjects were then divided into two groups: the swimming group (n= 10) and the control group (n= 10). The subjects were asked to exercise for 60 minutes a day, 3 times a week for 12 weeks with an exercise intensity of 50–70% HRmax. The following results were achieved: first, in terms of body composition, both body fat percentage and fat-free mass showed significant differences within the swimming group. There were also significant differences again in the posttest of difference between the two groups. Second, in terms of changes in physical fitness, there were, again, no significant changes in muscular strength between the two groups. However, muscular endurance, flexibility, and cardiopulmonary endurance showed significant differences in the swimming group’s test for difference within groups. Significant differences in both groups for the posttest of differences between groups were also seen. Third, in terms of vascular compliance, there was a significant increase in the right leg for the swimming groups’ test of difference within groups, as well as in the posttest of difference between groups.

Despite the broad rehabilitative potential of aquatic exercises, the relationship between aquatic exercise and the immune system has not been fully elucidated to date. In particular, there are few specific and delicate immunological approaches to the effect of water temperature on immunity. Thus, we examined the effect of water temperature on immunity during aquatic exercise. The animal tumor model was adopted to examine the impact of aquatic exercise at thermoneutral temperature (TT; 29°C) on immunity compared with aquatic exercise at body temperature (BT; 36°C). Tumor-bearing mice were made to swim in TT water or in BT water for 3 wk and immune cells and their functional activity were analyzed using FACS. Tumor growth was significantly suppressed in mice that exercised in TT than in BT water. The tumor control correlated with the increased number of NK (2-fold), γδT cells (2.5-fold), NKT (2.5-fold), and cytotoxic CD8 + T cells (1.6-fold), which play a critical role in anti-tumor immune responses. Furthermore, the functional activity was dramatically improved in the TT group, showing enhanced production of IFNγ in CD8 + T cells compared with the BT group. This study demonstrates that aquatic exercise in TT water may improve protective immune responses more effectively than in BT water. Although the effects of water temperature on immune function need further verification in humans, this study suggests that water temperature in human hydrotherapy may be important for improving immune function.

The purpose of this study is to define the effects of regular swimming exercise on the physical composition, physical strength, and blood lipids of middle-aged women. The subjects of this study are a total of 24 middle-aged women in the swimming group and the control group, with 12 women for each group. The swimming group performed swimming exercise for 60 min every time for 3 times a week, for a total of 12 weeks. For data processing, SPSS 21.0 statistics program was used to calculate the mean and standard deviation. For the difference verification on the change in mean for each group and between the groups, paired and independent t-tests were respectively used. As a result, for physical composition, the body fat rate decreased in the swimming group. Moreover, the difference verification result showed a statistically significant difference between the groups. For physical strength, the difference verification result for each group showed that the swimming group had a statistically significant difference in flexibility and cardiovascular endurance. Moreover, the difference verification result between the groups showed a statistically significant difference only for flexibility. For blood lipids, as a result of the difference verification for each group, T-C and TG showed a significant decrease, and HDL-C, a significant increase. However, in the difference verification result between the groups, only T-C and TG showed a statistically significant difference. With these results, it is considered that regular swimming exercise is effective for improving the physical composition, physical strength, and blood lipids of middle-aged women.