ABSTRACT
The effects of exercise and dietary therapy on the prevention of diabetic nephropathy (DN) were compared. Thirty-two male OLETF rats were divided into four groups (Ex, Diet, Sed, Pre) . Fourteen LETO rats served as the normal controls. Therapy was conducted for 10 weeks from age 22 to 31 weeks. The Ex group was trained by voluntary exercise, and the Diet group had a restricted food intake resulting in the same BW as that of the Ex group. The Ex developed a significant increase in urinary albumin excretion compared to the Diet group, although significantly less than the Sed group. Blood pressure in the Ex group showed a tendency to be higher during therapy. BW and serum lipids were significantly reduced, and glucose intolerance was improved in both the Ex and Diet groups. There were no differences in the metabolic indices between the Ex and Diet groups. The Ex group showed a significantly heavier kidney weight and a tendency for enlargement of the glomerular area and volume. The protective effect of DN through improvement of the metabolic dis-order by exercise might be offset by exercise-induced renal loads. Control of exercise intensity and blood pressure appear to be important as well as the improvement of glucose intolerance and lipid metabolisms in exercise therapy to prevent an occurrence and development of DN.
ABSTRACT
The effect of ingestion of a chilled carbohydrate and electrolyte solution on metabolic and hormonal responses and water-electrolyte balance was studied after two 5-km runs in hot outdoor conditions (Temp, 30.6-30.9°C ; humidity, 61.3-62.4%) . Eight healthy females (mean age 21.8 years) participated in : 1) a control experiment (Copt) with no fluid intake, 2) an experiment with 500 ml of tap water (WI), and 3) an experiment with 500 ml of sports beverage (SB) containing carbohydrate and electrolytes each of which were given after the 1st 5-km run, followed by a second 5-km run with an equivalent to 68.7-72.3% of VO<SUB>2</SUB>max. In the Cont, decreases in %ΔPV and blood glucose (BS) and increases in serum osmolality (Sosm), free fatty acid (sFFA) and plasma hormone concentrations related to regulation of the water-electrolyte balance in the body persisted after the 2 nd run. The intake of the sports beverage prevented hypoglycemia and ketoacidosis, as shown by an increase in sFFA and positive results for qualitative analysis of ketone body in the urine, and quick recovery of plasma volume following an endurance run under a hot environment. This study suggests that fluid replacement with a sports beverage containing carbohydrate and electrolytes was superior to plain water or no fluid ingestion in terms of metabolic and hormonal responses and the recovery of plasma volume and elevated rectal temperature following an endurance run under hot conditions.
ABSTRACT
A cross-sectional study was carried out to investigate the effect of physical exercise in daily lives of healthy women on the aging process in terms of maximal aerobic capacity (VO<SUB>2</SUB>max), body fat tissue mass (FTM), lean tissue mass (LTM), bone mineral density (BMD), serum triglyceride (TG), total cholesterol (TC), HDL-C and LDL-C concentrations, and systolic (SBP) and diastolic blood pressure (DBP) . These parameters are considered as risk factors of cerebrovascular disease and/or osteoporosis, which are the main causes of becoming bedridden and demented in middle-aged and older women. One hundred sixty-five healthy female volunteers aged 20 to 76 years participated in the study, 82 of whom were postmenopausal with a mean age at menopause of 49.7±3.1 years. Eighty-two of the subjects had been exercising regularly by jogging, swimming, aerobic dancing, or playing tennis more than twice a week for 2 years (Ex group), whereas 83 individuals had not been engaging in regular exercise (Cont group) . Serum lipid concentrations, SBP and DBP measurements at rest and treadmill VO<SUB>2</SUB>max and HRmax measurements were determined in the morning after an overnight fast. Whole-body BMD (TBMD), head, lumbar, arm and leg BMD, FTM and LTM were measured by dual-energy X-ray absorptiometry one to two hours after a light lunch. The mean and SD of each measurement were calculated for five-year age groups between 40 and 60 years and one group each under 40 and over 60 years.<BR>The results were as follows:<BR>1, VO<SUB>2</SUB>max (r=-0.590) and HRmax (r=-0.632) decreased significantly with age. The VO<SUB>2</SUB>max of the Ex group was significantly higher than that of the Cont group in all each age groups. However, no differences in the aging process in terms of HRmax were found between the two groups.<BR>2, Resting SBP (r=-0.391) and DBP (r=0.315) increased significantly with age. However, no hypertensive individuals (160/95 mmHg-) were found among the 165 subjects.<BR>3. Only serum TC (r=0.346) and LDL-C (r=0.339) among the blood constituents measured changed with age. No changes in serum HDL-C were detected with age. Lower TC (189.2±23.3 mg/dl) and higher HDL-C (72.2±10.9 mg/dl) were observed in eleven runners (49.7±7.7 years) among the subjects who participated frequently in official races than in subjects of the same ages in the Cont group. The highest serum HDL-C (75.8±15.8 mg/dl) and HDLC/TC ratios (0.362) were noticed among the subjects (n=26) who both regularly exercised and consumed alcoholic beverages.<BR>4. A tendency for FTM to increase and LTM to decrease with age were observed in both groups, and a lower %FTM (percentage of FTM to body weight) and higher %LTM were evident in the Ex group. Differences in %FTM and %LTM between the Ex and Cont groups at 40-45 years were significant.<BR>5. Partial and whole BMDs decreased significantly with age (TBMD-Age ; r=- 0.527) . Significantly higher leg BMDs in both the 20-39-year and 40-45-year groups, and spine and TBMD in the 20-39 years in the Ex group, who were premenopausal women, were shown. No significant differences in BMDs between the two groups were observed in postmenopausal women, but the Ex group tended to have higher partial and whole BMDs. The postmenopausal official race runners (n=5.52.6-1.5years) also had higher TBMD and leg BMD values than subjects of the same ages in the Cont group.<BR>6. Investigation of correlations between VO<SUB>2</SUB>max, LTM, FTM, BMDs and serum lipid concentrations, yielded a significantly higher correlation (r=0.669) between LTM (kg) and absolute VO<SUB>2</SUB>max (1/mm) . Although VO<SUB>2</SUB>max per LTM (VO<SUB>2</SUB>max/LTM) decreased with age (r=-0.595), VO<SUB>2</SUB>max/LTM in the Ex group was significantly higher than in the Cont group in each age group. The VO<SUB>2</SUB>max per body weight (ml/kg/min) was negatively correlated with %FTM (r=-0.442) and positively correlated with