DURING EXERCISE Research Articles

Interaction of physical trainings and coffee intakes in fuel utilization during exercise in rats

This study investigates the impact of exercises, coffee intakes, and physical trainings on fuel utilization in rats. Ninety-six rats were fed a control diet with either water (C) or coffee (CF; 0.12 g freeze-dried instant coffee/100 g body weight/d). Additionally, the animals go through physical training (TC and TCF) or no training (NTC and NTCF) for 4 weeks. For physical training, animals have to exercise on treadmills for 30 minutes (5 d per week, 15° incline, 0.5-0.8 km/h). At the end of week 4, the animals in each group were subdivided into three exercise groups: before exercise (BE), during exercise (DE), and after exercise (AE). The DE rats exercised on treadmills for 1 hour immediately before being sacrificed. Hemoglobin, hematocrit, glucose, glycogen, protein, triglyceride (TG), and free fatty acid (FFA) levels in the plasma, liver, and skeletal muscle of the rats were compared accordingly. Organ weights were also measured. Coffee-training interaction had a significant impact on heart weight, visceral fat, hemoglobin, hematocrit, liver glycogen in DE and AE, and liver triglyceride in DE and AE. Exercise (meaning exercised on a treadmill for 1 hour immediately before being sacrificed) training interaction was significant in liver glycogen, muscle glycogen in control diet and control diet with coffee, FFA and muscle TG levels at control diet with coffee group. Exercise-coffee interactions significantly influenced the FFA with no training groups. Exercise-coffee-training interaction significantly effects on FFA, Liver TG and Muscle TG. Coffee intakes can increase lipolysis during exercising but coffee consumptions delay the recovery of liver glycogen levels in trained rats after exercising. Coffee intakes can increase lipolysis during exercising but coffee consumptions delay the recovery of liver glycogen levels in trained rats after exercising. Coffee can be an effective ergogenic aid during exercise for physically trained rats.

Freeze-dried instant coffee can promote the activities of antioxidant enzymes and induce weight loss but also aggravate the plasma cholesterol profile in rats

ObjectiveThis study investigated the effect of instant coffee on antioxidant enzyme activity and plasma cholesterol profile during exercise in rats. MethodsForty eight rats were fed a control diet with water (C) or a control diet with a coffee solution (CF). At the end of week 4, animals in each dietary group were subdivided into three exercise groups: before exercise (BE), during exercise (DE), and after exercise (AE). DE groups were exercised on a treadmill for 1 h immediately before being sacrificed. Animals in the AE groups were allowed to take a rest for 1 h after exercise. Antioxidant enzyme activities of the C and CF groups were evaluated with activities of catalase in plasma and superoxide dismutase, the ratio of reduced glutathione to oxidized glutathione, and the level of malondialdehyde in the liver. Plasma concentrations of triacylglycerol, total cholesterol, and high-density lipoprotein cholesterol were also compared. ResultsFinal body weights and food intakes of the CF group were significantly lower than those of the C group. Catalase activities of the CF group were higher than those of the C group BE and AE. Reduced glutathione/oxidized glutathione of the CF group was significantly higher than that of the C group BE and DE. Superoxide dismutase activities of the CF group were higher than those of the C group regardless of exercise. Compared with the C group, there was an increase of total cholesterol and a decrease of high-density lipoprotein cholesterol levels in the CF group. Malondialdehyde levels in the CF group were higher than those in the C group BE and AE. ConclusionIt is suggested that freeze-dried instant coffee can promote activities of antioxidant enzymes and induce weight loss but also aggravate the plasma cholesterol profile in rats.

Coffee intake can promote activity of antioxidant enzymes with increasing MDA level and decreasing HDL-cholesterol in physically trained rats

This study investigated the effect of coffee intake and exercise on the antioxidative activity and plasma cholesterol profile of physically trained rats while they were exercising. Forty eight rats were under either the control diet with water (C) or control diet with coffee (CF) and at the same time they were given physical training for 4 weeks. In terms of physical training, the rats were exercised on a treadmill for 30 minutes everyday. At the end of 4 weeks, animals in each dietary group were subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). Animals in the DE group were exercised on a treadmill for one hour, immediately before being sacrificed. Animals in the AE group were allowed to take a rest for one hour after exercise. TG levels were significantly high in coffee intake group than in control group. Also TG level of AE group was significantly higher than that of BE group. Exercise and coffee-exercise interaction effects were significant in total cholesterol (P = 0.0004, 0.0170). The AE of coffee intake group showed highest total cholesterol levels. HDL-cholesterol was significantly lower in coffee intake group than in control group. Coffee, exercise, and coffee-exercise interaction effects were significant in SOD (P = 0.0001, 0.0001, and 0.0001). The AE and BE of coffee intake group showed higher SOD levels than the other four groups. Catalase activities were significantly higher in coffee intake group than control group. No significant main effect was found in GSH/GSSG. Coffee, exercise, and coffee-exercise interaction effects were significant in MDA levels (P = 0.0464, 0.0016, and 0.0353). The DE and AE of coffee intake group and the DE of control group showed higher MDA levels than the BE of control group. Therefore, coffee intake can promote activities of antioxidant enzyme but it also increases MDA and decreases HDL-cholesterol in physically trained rats.

Cooling strategies improve intermittent sprint performance in the heat of athletes with tetraplegia

BackgroundPrecooling has been shown to enhance performance in repeated sprint exercise in able-bodied subjects in a hot environment. Spinal cord injury causes thermoregulatory impairment with a detrimental effect on performance....

Vitamin B6 Deficiency can Reduce Fuel Storage and Utilization in Physically Trained Rats

This study investigated the effect of vitamin B6 deficiency on the utilization and recuperation of stored fuel in physically trained rats. 48 rats were given either vitamin B6-deficient (B6-) diet or control (B6) diet for 4 weeks and were trained on treadmill for 30 minutes daily. All animals were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The DE group was exercised on treadmill for 1 hour just before being sacrificed. Animals in the AE group were allowed to take a rest for 2 hours after being exercised like the DE group. Glucose and free fatty acids were compared in plasma. Glycogen and triglyceride were compared in liver and skeletal muscle. Protein levels were compared in plasma, liver, and skeletal muscle. Compared with the B6+ group, plasma glucose levels of the B6- group were significantly lower before and after exercise. Muscle glycogen levels of the B6- group were significantly lower than those of the B6+ group regardless of exercise. The liver glycogen level of the B6- group was also significantly lower than that of B6+ group during and after exercise. Before exercise, plasma free fatty acid levels were not significantly different between the B6+ and B6- groups, and plasma free fatty acid levels of the B6- group were significantly lower during and after exercise. The muscle triglyceride level of the B6- group was significantly lower than that of the B6+ group before exercise, and there were no differences between B6+ and B6- groups during and after exercise. Liver triglyceride levels were not significantly different between B6+ and B6- groups. Plasma protein levels of the B6- group were lower than those of B6+ before and after exercise. Muscle protein levels of the B6- group were not significantly different from those of the B6 group. Liver protein levels of the B6- group were significantly lower than that of the B6+ group after exercise. Liver protein levels of both B6+ and B6- groups were not significantly changed, regardless of exercise. Thus, it is suggested that vitamin B6 deficiency may reduce fuel storage and utilization with exercise in physically trained rats.

The effects of physical training on antioxidative status under exercise-induced oxidative stress

This study investigated the effect of physical training and oxidative stress on the antioxidative activity and on plasma lipid profile. Forty eight rats were given either a physical training or no training for 4 weeks and were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The antioxidative activity was evaluated with the activities of catalase in plasma and superoxide dismutase (SOD), the ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) and the level of malondialdehyde (MDA) in liver. The plasma concentrations of triglyceride (TG), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C)) were also compared. Compared to those of non-training group, catalase activities of training group were lower before exercise but higher during and after exercise. SOD activities were higher regardless of exercise. GSH/GSSG ratio was higher before exercise but was not significantly different during exercise and even lower after exercise. There were no differences between non-training group and training group in MDA levels regardless of exercise. Compared to those of non-training group, atherosclerotic index of training group was lower after exercise and there were no significant differences before and during exercise. There were no differences between non-training group and training group in HDL-C regardless of exercise. These results suggest that moderate physical training can activate antioxidant defenses and decrease the atherosclerotic index and this beneficial effect is evident under exercise-induced oxidative stress.

Effect of vitamin B6 deficiency on the utilization of fuel with exercise in rats

Forty eight rats were fed either a control diet (+B6) or vitamin B6 deficient diet (-B6) diet for 4 weeks and were subdivided into 3 groups: before exercise (BE); during exercise (DE); after exercise (AE). DE group were exercised on treadmill for 1 hours just before sacrifice at the end of 4th week of respective diet and AE group were recuperated 1 hour after exercised like DE group. The levels of glucose (GLU), glycogen (GLY), protein (PRO), free fatty acid (FFA) and triglyceride (TG) were compared in plasma, liver and skeletal muscle. There were no differences between +B6 and -B6 in muscle and liver GLY before and during exercise but liver GLY was not recovered and 40% lower after exercise in –B6 group. Muscle TG was decreased with exercise in +B6 group(15% in DE, 28% in AE) but was not changed with exercise in –B6 group. Liver TG was decreased with exercise in -B6 group(26% in AE) but was not changed with exercise in +B6 group. Plasma FFA was increased with exercise in +B6 group(18% in DE, 16% in AE) while was decreased with exercise in –B6 group(35% in DE, 38% in AE). There were no changes in plasma, liver and muscle PRO of both +B6 and –B6 group with exercise. These results suggest that vitamin B6 deficiency may influence the utilization of fuel stores.

Allium Vegetable Diet Can Reduce the Exercise-Induced Oxidative Stress but Does Not Alter Plasma Cholesterol Profile in Rats

Aims and Methods: This study investigated the effect of Allium vegetable intake on the antioxidative activity and on the plasma cholesterol profile during exercise in rats. Ninety rats were fed either a control diet or a diet with added Allium sativum (AS), Allium cepa (AC), Allium fistulosum (AF), or Allium tuberosum (AT) for 4 weeks and were then subdivided into three groups: before exercise (BE), during exercise (DE), and after exercise (AE). The DE group was exercised on a treadmill for 1 h immediately before being sacrificed. Animals in the AE group were allowed to take a rest for 2 h after having been exercised like the DE group. The antioxidative activity of the Allium vegetables was evaluated with the activities of catalase in plasma and superoxide dismutase (SOD), the ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) and the level of malondialdehyde (MDA) in liver. The plasma concentrations of triglyceride, total cholesterol, and high-density lipoprotein cholesterol were also compared. Results: In AS, AC, AF and AT animals, the ratios of GSH/GSSG were significantly higher than those of the control animals in BE and AE. The level of liver MDA was lower than that of control animals in AE. Compared to control animals, catalase activity of AS animals was higher in BE but was lower in AE while SOD activity of AS animals was lower in both BE and AE. Catalase activity of AC animals was higher in BE and DE while SOD activity of AC animals was higher in DE. There were no differences between AF and control in catalase activities regardless of exercise. There were no differences between control animals and AT animals in SOD activities regardless of exercise. Plasma cholesterol profiles were not significantly different in rats fed different Allium vegetable diets. Conclusion: It is suggested that Allium vegetable diets have antioxidative activities and can reduce the oxidative stress that results from exercise in rats but do not alter the plasma cholesterol profile.

Effects of Allium Vegetables on Energy Stores and Utilization in Exercising Rats

This study investigated the effect of allium vegetable intake on the storage and utilization of energy substrates before, during, and after exercise in tissues of rats. Ninety rats were fed either a control diet or a diet with added Allium sativum (AS, garlic), Allium cepa (AC, onion), Allium fistulosum (AF, spring onion), or Allium tuberosum (AT, Chinese chives) for 4 weeks and were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The DE group was exercised on treadmill for 1 hour just before being sacrificed at the end of 4th week of the dietary treatment rats in the AE group were allowed to recuperate for 2 hours after being exercised like the DE group. The levels of glycogen (GLY), triglyceride (TG) and protein (PRO) were compared in liver and skeletal muscle. In the AS diet animals, the level of liver GLY was significantly higher than those of control animals in the BE, DE and AE groups. The level of muscle TG also tended to be higher in BE, but lower in AE than in control animals. In AC animals, the level of muscle GLY was significantly lower than those of control animals in BE, DE and AE. The level of muscle TG also tended to be higher than those of control animals in BE and DE but tended to be lower in AE. In AF animals, the level of muscle GLY was significantly lower than those of control animals in BE, DE and AE. The level of muscle TG was also significantly lower than those of control animals in BE, DE and AE groups. In AT animals, the level of muscle GLY was significantly lower than those of control animals in BE, DE and AE. These results suggest that Allium sativum diets enhance the capacity to store fuel before as well as during exercise and increases the potential to utilize the stored fuel during exercise.

Nutrition and Exercise Introduction and Overview

Concern with physical fitness has heightened inter est in nutrition in relation to exercise physiology and biochemistry. This was evidenced by 400 participants in this symposium in which seven contributions were presented. The symposium was opened by Dr. Vishwa Singh, who presented an overview on nutrition and exercise. In his overview, Dr. Singh drew attention to the role of oxidative damage that occurs in exercise, which also contributes to the etiology of certain chronic diseases in aging. Evidence has been accumulating to suggest that ex ercise is damaging. Stable free radical accumulation has been observed in skeletal muscles after exercise, and it has also been reported that vitamin E deficiency exacerbates the leakage of skeletal muscle enzymes into the blood. A change in the redox status of blood antioxidants is shown with glutathione oxidation dur ing exercise; this has been observed not only in human blood, but also in animal tissues. There is evidence that some tissues suffer an ischemia-reperfusion type of injury after exercise; i.e., those tissues that have reduced circulation during exercise experience a reoxygenation burst immediately after cessation of exer cise. Dr. Singh pointed out that there is some evidence that antioxidant nutrients (vitamin C, vitamin E and /3-carotene)can minimize the oxidative damage during exercise. Furthermore, nutrition and exercise seem to share their roles in prevention/management of certain chronic diseases (i.e., hypertension, coronary heart disease, cancer and osteoporosis). Thus, Dr. Singh proposed that proper nutrition, particularly adequate intake of antioxidant nutrients, be made an integral part of the regular exercise regimen for prevention of disease and promotion of optimal health. The importance of antioxidants in minimizing in dices of oxidative damage was investigated in both human and animal studies as reported by Dr. Lester Packer and his colleagues. In moderately trained hu mans it was found that repeated sessions of mild ex ercise did not increase urinary output of an oxidatively modified RNA base, 8-hydroxyguanosine, nor did supplementation with vitamins Eand C and /3-carotene have an effect on its excretion. Substantial increases in plasma concentrations of the antioxidants occur as a result of supplementation. This study showed that exercise induces increases in plasma vitamin C con centration. The percentage of the vitamin C in the reduced form also increases. Because a large oxidation of blood glutathione occurred during exercise, it was suggested that some of the reducing equivalents from glutathione might be used to increase the proportion of plasma vitamin C in its reduced form. In another study with endurance-trained rats, it was found that such training causes a doubling in oxida tively modified protein in muscle, as measured by protein carbonyls, which return to normal levels with detraining. No changes in protein carbonyl content of liver with training or detraining were seen. It is known that dietary (energy) restriction results in prolongation of life span. It is still unclear, however, whether exercise has positive or negative effects on longevity. Effects of exercise and food restriction on longevity were investigated by Dr. John O. Holloszy's laboratory.

GLUCOSE TURNOVER DURING EXERCISE IN MAN*

Annals of the New York Academy of SciencesVolume 301, Issue 1 p. 45-55 GLUCOSE TURNOVER DURING EXERCISE IN MAN* John Wahren, John Wahren Department of Clinical Physiology Karolinska Institute Huddinge Hospital S-141 86 Huddinge, SwedenSearch for more papers by this author John Wahren, John Wahren Department of Clinical Physiology Karolinska Institute Huddinge Hospital S-141 86 Huddinge, SwedenSearch for more papers by this author First published: October 1977 https://doi.org/10.1111/j.1749-6632.1977.tb38184.xCitations: 47 * This work was supported by the Swedish Medical Research Council (19-X-3108) and the National Institute of Health (AM-13526). AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume301, Issue1The Marathon: Physiological, Medical, Epidemiological, and Psychological StudiesOctober 1977Pages 45-55 RelatedInformation

AN INDIRECT METHOD FOR ESTIMATING TISSUE PRESSURE WITH SPECIAL REFERENCE TO TISSUE PRESSURE IN MUSCLE DURING EXERCISE.

AbstractTissue pressure is one of the determinants of capillary filtration and appears to be a major limiting factor of filtration exchange during muscular exercise. Since direct measurement of tissue pressure through a needle was considered impossible, an indirect method was developed to record tissue pressure in skeletal muscle during rest and exercise. This method is based on the fact that veins are normally collapsible and that the pressure inside patent veins can never be less than the extramural pressure i. e. tissue pressure. When the tissue pressure exceeds the central venous pressure, the pressure in the local veins is dictated by, and becomes a measure of the tissue pressure. Instead of measuring this pressure the changes in volume of the muscle were recorded plethysmographical‐ly and the pressure below which changes of central venous pressure did not influence volume was noted. This pressure was regarded as corresponding to the minimum tissue pressure. The maximum tissue pressure was obtained from distensibility curves for the veins. The accuracy of the method is about 2 cm H2O. During rest the tissue pressure was only little above zero and rose during exercise in relation to the amount of filtrate accumulated in the muscle.