EFFECTS OF HIGH INTENSITY EXERCISE TRAINING ON CARDIOVASCULAR FUNCTION,OXYGEN UPTAKE, INTERNAL OXYGEN TRANSPORT AND OSMOTIC BALANCE IN CHINOOK SALMON(ONCORHYNCHUS TSHAWYTSCHA) DURING CRITICAL SPEED SWIMMING

SUMMARYTo examine cardiorespiratory plasticity, cardiovascular function, oxygen consumption, oxygen delivery and osmotic balance were measured at velocities up to critical swimming speed (Ucrit) in seawater-adapted chinook salmon. We used two groups of fish. The control group had swum continuously for 4 months at a low intensity (0.5 BL s-1)and the other was given a high-intensity training regimen (a Ucrit swim test on alternate days) over the same period of time. Compared with available data for other salmonid species, the control group had a higher maximum oxygen consumption(Ṁo2max; 244μmol O2 min-1 kg-1), cardiac output(Q̇max; 65 ml min-1 kg-1) and blood oxygen content(CaO2; 15 ml O2 dl-1). Exercise training caused a 50% increase in Ṁo2max without changing either Ucrit or CaO2, even though there were small but significant increases in hematocrit, hemoglobin concentration and relative ventricular mass. During swimming, however,exercise-trained fish experienced a smaller decrease in body mass and muscle moisture, a smaller increase in plasma osmolality, and reduced venous oxygen stores compared with control fish. Consequently, exercise training apparently diminished the osmo—respiratory compromise, but improved oxygen extraction at the tissues. We conclude that the training-induced increase in Ṁo2max provided benefits to systems other than the locomotory system, such as osmoregulation,enabling trained fish to better multitask physiological functions while swimming. Furthermore, because a good interspecific correlation exists between Ṁo2max and arterial oxygen supply(Ṫo2max; r2=0.99) among temperate fish species, it is likely that CaO2 and Q̇max are principal loci for cardiorespiratory evolutionary adaptation but not for intraspecific cardiorepiratory plasticity as revealed by high intensity exercise training.

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Effects of high-intensity exercise training on body composition, abdominal fat loss, and cardiorespiratory fitness in middle-aged Korean females

Applied Physiology Nutrition and Metabolism ◽

10.1139/h2012-084 ◽

2012 ◽

Vol 37 (6) ◽

pp. 1019-1027 ◽

Cited By ~ 20

Author(s):

Man-Gyoon Lee ◽

Kyung-Shin Park ◽

Do-Ung Kim ◽

Soon-Mi Choi ◽

Hyoung-Jun Kim

Keyword(s):

Oxygen Consumption ◽

Exercise Training ◽

High Intensity ◽

Maximal Oxygen Consumption ◽

Training Group ◽

Abdominal Fat ◽

High Intensity Exercise ◽

Whole Body ◽

Fat Loss ◽

Intensity Training

The primary purpose of this study was to investigate the effects of high-intensity exercise training under relatively equal energy expenditure on whole body fat and abdominal fat loss, and cardiorespiratory fitness. Twenty-two untrained middle-aged Korean females were randomized into one of the following groups: control, low-intensity training group (LI), and high-intensity training group (HI). Subjects completed 14 weeks of training at 50% maximal oxygen consumption (LI) or 70% maximal oxygen consumption (HI) with the volume of exercise equated relative to kilograms of body weight. Weekly exercise volumes were 13.5 METs⋅h/week for the first 4 weeks, 18 METs⋅h/week for next 5 weeks, and 22.5 METs⋅h/week for the final 5 weeks. Data were analyzed using 2-way repeated measures ANOVA with post hoc test, using Bonferroni’s correction. HI showed significant reductions in fat mass (p < 0.05), total abdominal fat (p < 0.01), and subcutaneous abdominal fat (p < 0.01). LI reduced total abdominal fat (p < 0.05), but there were no other significant changes found in the control or LI groups. Maximal oxygen consumption was enhanced in both HI and LI with no significant group difference. High-density lipoprotein cholesterol increased significantly in HI (p < 0.05). IL-6, C-reactive protein, TNF-α, and other blood lipids were unaltered following training. Results indicate that high-intensity exercise training is more beneficial in whole body and abdominal fat loss; however, cardiorespiratory enhancement shows a dose–response relationship with weekly exercise volume. It is suggested that 14 weeks of aerobic exercise training at either high- or low-intensity is not sufficient enough to induce changes in levels of inflammatory proteins.

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PO-099 Effects of long-term high-intensity exercise training on renal local renin-angiotensin system in rats

Exercise Biochemistry Review ◽

10.14428/ebr.v1i3.11733 ◽

2018 ◽

Vol 1 (3) ◽

Author(s):

Zhang Dang ◽

Jianmin Cao ◽

Xian Guo ◽

Yanlong Niu ◽

Hui Xiao

Keyword(s):

Exercise Training ◽

Renal Injury ◽

High Intensity ◽

Renin Angiotensin System ◽

Exercise Group ◽

High Intensity Exercise ◽

Renin Activity ◽

Control Group ◽

Angiotensin System

Objective Exercise stimulation to the body of the first stress: blood changes, regulated by the renin-angiotensin system. Long-term high-intensity exercise training will lead to changes in kidney structure and function, resulting in renal injury. This will not only affect training and competition, but also affect the health of athletes, thus it is becoming an influential factor in the occurrence and development of excessive fatigue. At present, the mechanism of renal injury and proteinuria caused by exercise is not very clear. Therefore, this study conducted an in-depth study on the upstream mechanism of renal blood flow changes from the molecular level and explored the effects of 6-week high-intensity exercise training on the renal local renin-angiotensin system in rats. Methods 30 SD male rats (8 weeks old) were randomly divided into control group (10) and exercise group (20). Then according to different time, the exercise group (20) was divided into two groups on average, which are 0h group and 24h group. The rats in the control group did not do any exercise, and the rats in the exercise group were trained to run on the platform with high intensity for 6 weeks. At the beginning of the sixth week, the urine of rats from different group were selected randomly, and the urine NGAL, urinary microalbumin (mAlb), urinary creatinine (UCr) and total urine protein (TP) were tested, to determine the rat model of exercise-induced renal injury with proteinuria. After training on the 6th weekend, the renal tissue renin activity and angiotensin Ⅱ (Ang Ⅱ) content in right kidney were tested. At the same time, the left kidney of the rat was taken to make HE staining sections. Results (1) The mAlb, Alb/Cr and TP of the exercise group were higher than those of the control group, while the UCr content was lower than that of the control group. There was a significant difference between mAlb and TP in the exercise group and the control group(p<0.05). UCr, mAlb/Cr were significantly different from the control group(p<0.01). The urine NGAL concentration in the exercise group was higher than that in the control group, and the difference was significant(p<0.05). (2) The glomerulus of the rats in the 0h group showed obvious congestion, swelling and erythrocyte exudation. The tissue morphology of rats in the 24h group recovered slightly, but it was still different from the control group. (3) The renin activity and Ang Ⅱ were the lowest in the 0h group, and the renin activity and Ang Ⅱ were highest in the 24h group. There is a very significant difference between the groups(p<0.01). Conclusions (1) The 6-week high-intensity training used in this study increased the levels of NGAL, TP, and mAlb in the urine of rats, and successfully established a rat model of exercise-induced renal injury with proteinuria. (2) Long-term high-intensity exercise training can cause obvious congestion, swelling, erythrocyte exudation in rat glomeruli, which can’t return to the quiet level 24 hours after exercise. (3) Renal injury caused by exercise decreased the expression of local renin activity and angiotensin II in the kidney, and the recovery of renal renin activity and angiotensin II was increased 24h after exercise.

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Effect of exercise training at different intensities on fat metabolism of obese men

Journal of Applied Physiology ◽

10.1152/japplphysiol.00030.2001 ◽

2002 ◽

Vol 92 (3) ◽

pp. 1300-1309 ◽

Cited By ~ 74

Author(s):

Dorien P. C. Van Aggel-Leijssen ◽

Wim H. M. Saris ◽

Anton J. M. Wagenmakers ◽

Joan M. Senden ◽

Marleen A. Van Baak

Keyword(s):

Exercise Training ◽

High Intensity ◽

Fat Metabolism ◽

Fat Oxidation ◽

High Intensity Exercise ◽

Control Group ◽

Low Intensity ◽

Obese Subjects ◽

Total Fat ◽

Low Intensity Exercise

The present study investigated the effect of exercise training at different intensities on fat oxidation in obese men. Twenty-four healthy male obese subjects were randomly divided in either a low- [40% maximal oxygen consumption (V˙o 2 max)] or high-intensity exercise training program (70%V˙o 2 max) for 12 wk, or a nonexercising control group. Before and after the intervention, measurements of fat metabolism at rest and during exercise were performed by using indirect calorimetry, [U-13C]palmitate, and [1,2-13C]acetate. Furthermore, body composition and maximal aerobic capacity were measured. Total fat oxidation did not change at rest in any group. During exercise, after low-intensity exercise training, fat oxidation was increased by 40% ( P < 0.05) because of an increased non-plasma fatty acid oxidation ( P < 0.05). High-intensity exercise training did not affect total fat oxidation during exercise. Changes in fat oxidation were not significantly different among groups. It was concluded that low-intensity exercise training in obese subjects seemed to increase fat oxidation during exercise but not at rest. No effect of high-intensity exercise training on fat oxidation could be shown.

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