This study was designed to examine the relationship between exercise diuresis and running load, following seven types of running events by five male athletes, aged 19 to 25 years. None had a history of renal disease.
Informed written consent was obtained from all subjects prior to the study.
1. Compared to the resting levels, significant increases in the urinary volume were observed thirty minutes after performing a 400-meter dash, but not after the other exercises.
2. The changes in creatinine concentration (30 min after exercise/after warm-up) were inversely proportional to the changes in urinary volume, indicating that exercise diuresis depends on the depressed reabsorption of water in the renal tubules.
3. The absence of diuresis after 60 and 100-meter sprints, indicates that the phosphagen system is mainly employed for energy supply.
4. The urinary volumes after 200, 300 and 400-meter dashs highly correlated with the changes in the excretion rate of pyruvate. This suggests that exercise diuresis is related to the lactic system in energy metabolism.
5. The decreased excretion rate of creatinine after 800 and 1, 500-meter runs indicates that GFR is reduced by these exercises. Furthermore, the lactic energy system caused the diuretic effect. Thus, even though secretion of antidiuretic hormones is increased following exercise, their effectiveness is reduced by lactic oxygen deficit.

For revealing the post exercise proteinuria, the variation of leucine aminopeptidase (LAP) and γ-glutamyltranspeptidase (γ-GTP) activities were observed to know the fluctuation of the substances excreted in the urine and the composition of the urinary protein in 4 college athletes aging from 19 to 21 years before and after 10-mile road race.
The results obtained are as follows:
1) During the race and in the early stage of recovery the excretion of creatinine, uric acid, and urea-nitrogen decreased, and in this term clearance in the kidney reduced. More than 60 minutes after the end of the road race, the excretion of these substances returned to the level before the race.
2) The urinary pH value began to increase just after the race, became alkaline at pH more than 7 and less than 8 in all the subjects 30 to 60 minutes after the race, 90 to 120 minutes after the race it returned to level obtained before the race.
3) In the term when the excretion of the substances decreased, as described in the above 1), protein was much excreted, and it gradually decreased in the urine collected 60 to 90 minutes and later after the race, but the level of the excreted protein was still higher than that obtained before the race.
4) The Albumin/Globulin ratio of the urinary protein was low at rest, but in the early stage of recovery it was higher than 1, but in the later stage of recovery it decreased.
5) LAP and γ-GTP activities were also high in the term when protein was much excreted, but gradually decreased following the progress of recovery. LAP activity in the urine collected 120 to 150 minutes after the race recovered nearly to the level before the race, but γ-GTP remained still at a rather high level, and indicated the difference in the composition of the post exercise proteinuria.
6) It was estimated that the post exercise proteinuria would include not only the leaked plasma component caused by increase of the permeability but also some part derived from the renal tissue.

An experiment was carried with 15 males (60.2 years old on the average) and 12 females (43.3 years old on the average) who had made it a rule to run regularly for exercise in daily life. The females were before the climacteric stage. Its purpose was to study the serum cholesterol fraction in relation to food intake and distance, duration, and speed of running for exercise.
The following results were obtained.
1) The composite variable of serum lipid synthesis tended to be affected more distinctly by the group with food intake as indicator than by the group with locomotion as indicator. It seemed to be influenced primarily by the amount of food intake to a remarkable extent, and secondarily by the group with locomotion as indicator. In this group an increase in consumption of energy with the practice of running exercises participated in bringing about such influence.
2) It was suggested that great care should be taken for food intake in performing running exercises as a habit, taking energy consumed by running into consideration.

Fourteen female handball players who were candidates for Olympic representative team were asked to run 12 minutes, and the relationship between the variation of the urinary components and the variations of the running speed and the heart beats was researched.
The obtained results in short are in the following:
1) The covered distance of the 12-minute running was from 2, 385 meters to 3, 050 meters, and the average was 2, 830±196.6 meters.
2) The heart beat rate quickly recovered for about 5 minutes after running, and then gradually reduced; after 30 minutes the rate was considerably higher than the level before the running in many cases.
3) The urinary volume was obviously less after the running than that before it.
4) The 1-hour after urine including the running time contained much pyruvates and lactates exhausted therein, and then the excretion amount reduced to the previous level. The ratios of Pyruvic acid/Creatinine and Lactic acid/Creatinine showed similar tendencies. The ratio of Pyruvic acid/Creatinine before the running against that after the running showed positive correlation with the running speed more than 230m/min., but showed a negative correlation clearly with the recovering rate of the heart beat after 30 minutes being higher than 60%. It suggests that the excretion of urinary pyruvate increase with more anaerobic factors for energy production under the conditions of the higher speed running and the larger oxygen debt.
5) The urinary citrate obviously decreased just after the running, but in recovered considerably in the urine obtained after 2 hours. The ratio of Citric acid/Creatinine was low just after the running. The variations appears not to be simply due to the reduction of renal clearance.
6) The urinary creatinine tended to reduce in the urine obtained 1-hour after the running, and particularly with the urinary pyruvate more than 50μg/ml there was observed clear negative correlation with creatinine which showed lower concentration with more anaerobic factors; it suggests some reduction of renal clearance.

Several studies have shown that low cardiorespiratory fitness (CRF) or heavy alcohol consumption is risks of total or certain types of cancer death. However, the combined influence of CRF and drinking habits on total cancer mortality is not clear. The purpose of this study was to investigate the joint effect of CRF and drinking habits on total cancer mortality among Japanese men. We evaluated the CRF and drinking habits on risk of total cancer mortality in 8,760 Japanese men (age: 19-59 yr) who were given a submaximal exercise test, a medical examination test, and questionnaires on their health habits. CRF was measured using a cycle ergometer test, and the men were classified into two categories by CRF levels based on the reference value of CRF (R-CRF) in “Physical Activity Reference for Health Promotion 2013” (Under R-CRF and Over R-CRF). Also, the men were assigned to Non Drinking, Moderate Drinking, and Heavy Drinking categories. There were 178 cancer deaths during the 20-yr follow-up period. Relative risk and 95% confidence intervals for total cancer mortality were obtained using the Cox proportional hazards model while adjusting for age, body mass index, systolic blood pressure, and smoking habits. Using the Under R-CRF & Heavy Drinking group as reference, the relative risk and 95% confidence intervals were 0.37 (0.16–0.85) for the Over R-CRF & Non Drinking group. This result suggests that Japanese male with a high CRF and a low drinking habit have a lower risk of total cancer mortality.

Approximately 40%–65% of new fitness club (FC) members cancel their membership within 6 months. To prevent such cancellations, it is essential to identify members at high risk of doing so. This study developed a model to predict the probability of discontinuing FC membership among new members. We conducted a cohort study and enrolled participants from 17 FCs in Japan. We asked 5,421 individuals who became members from March 29, 2015 to April 5, 2016 to participate in the study; 2,934 completed the baseline survey, which was conducted when the participants became FC members. We followed up the participants until September 30, 2016. We excluded 883 participants with missing values and 69 participants under aged 18 years; thus, our analysis covered 1,982 individuals. We conducted the random survival forest to develop the prediction model. The mean follow-up period was 296.3 (standard deviation, 127.3) days; 488 participants (24.6%) cancelled their membership during the follow-up. The prediction model comprised 8 predictors: age; month of joining FC; years of education; being under medical follow-up; reasons for joining FC (health improvement, relaxation); and perceived benefits from exercise (maintaining good body weight, recognition of one’s ability by other). The discrimination and calibration were acceptable (C statistic: 0.692, continuous ranked probability score: 0.134). Our findings suggest that the prediction model could assess the valid probability for early FC cancellation among new members; however, a validation study will be needed.

Background/Aims: Metabolic dysfunction-associated steatotic liver disease (MASLD) was recently proposed as an alternative disease concept to nonalcoholic fatty liver disease (NAFLD). We aimed to investigate the prognosis of patients with biopsy-confirmed MASLD using data from a multicenter study. Methods: This was a sub-analysis of the Clinical Outcome Nonalcoholic Fatty Liver Disease (CLIONE) study that included 1,398 patients with NAFLD. Liver biopsy specimens were pathologically diagnosed and histologically scored using the NASH Clinical Research Network system, the FLIP algorithm, and the SAF score. Patients who met at least one cardiometabolic criterion were diagnosed with MASLD. Results: Approximately 99% of cases (n=1,381) were classified as MASLD. Patients with no cardiometabolic risk (n=17) had a significantly lower BMI than patients with MASLD (20.9 kg/m2 vs. 28.0 kg/m2, P<0.001), in addition to significantly lower levels of inflammation, ballooning, NAFLD activity score, and fibrosis stage based on liver histology. These 17 patients had a median follow-up of 5.9 years, equivalent to 115 person-years, with no deaths, liver-related events, cardiovascular events, or extrahepatic cancers. The results showed that the prognosis for pure MASLD was similar to that for the original CLIONE cohort, with 47 deaths and one patient who underwent orthotopic liver transplantation. The leading cause of death was extrahepatic cancer (n=10), while the leading causes of liver-related death were liver failure (n=9), hepatocellular carcinoma (n=8), and cholangiocarcinoma (n=4). Conclusions Approximately 99% of NAFLD cases were considered MASLD based on the 2023 liver disease nomenclature. The NAFLD-only group, which is not encompassed by MASLD, had a relatively mild histopathologic severity and a favorable prognosis. Consequently, the prognosis of MASLD is similar to that previously reported for NAFLD.