Five months of daily standardized exercise for sedentary monkeys

A system to physically exercise rhesus monkeys is described, based on their natural capacity to climb. It is composed of an enclosure where a motor-driven rope is continually going down. The two stage training to this task is easily performed. The total work of each run, evaluated with the weight of the animal and the distance climbed, may be very stable. It was used to provide five sedentary monkeys with daily physical training for five months.     

Thermoregulation in hyperhydrated men during physical exercise

The influence of hyperhydration on thermoregulatory function was tested in 8 male volunteers. The subjects performed cycle exercise in the upright position at 52% Vo2max for 45 min in a thermoneutral (Ta = 23 degrees C) environment. The day after the control exercise the subjects were hyperhydrated with tap water (35 ml X kg-1 of body weight) and then performed the same physical exercise as before. Total body weight loss was lower after hyperhydration (329 +/- 85 g) than during the control exercise (442 +/- 132 g), p less than 0.05. The decrease in weight loss after hyperhydration was probably due to a decrease in dripped sweat (58 +/- 64 and 157 +/- 101 g, p less than 0.05). With hyperhydration delay in onset of sweating was reduced from 5.8 +/- 3.2 to 3.7 +/- 2.0 min (p less than 0.05), and rectal temperature increased less (0.80 +/- 0.20 and 0.60 +/- 0.10 degrees C, p less than 0.01). The efficiency of sweating was higher in hyperhydrated (81.4%) than in euhydrated subjects (57.1%), p less than 0.01. It is concluded that hyperhydration influences thermoregulatory function in exercising men by shortening the delay in onset of sweating and by decreasing the quantity of dripped sweat. As a result, the increases in body temperature in hyperhydrated exercising men are lower than in normally hydrated individuals.     

Oxidant,antioxidant and physical exercise

Generation of reactive oxygen species (ROS) is a normal process in the life of aerobic organisms. Under physiological conditions, these deleterious species are mostly removed by the cellular antioxidant systems, which include antioxidant vitamins, protein and non-protein thiols, and antioxidant enzymes. Since the antioxidant reserve capacity in most tissues is rather marginal, strenuous physical exercise characterized by a remarkable increase in oxygen consumption with concomitant production of ROS presents a challenge to the antioxidant systems.An acute bout of exercise at sufficient intensity has been shown to stimulate activities of antioxidant enzymes. This could be considered as a defensive mechanism of the cell under oxidative stress. However, prolonged heavy exercise may cause a transient reduction of tissue vitamin E content and a change of glutathione redox status in various body tissues. Deficiency of antioxidant nutrients appears to hamper antioxidant systems and augment exercise-induced oxidative stress and tissue damage. Chronic exercise training seems to induce activities of antioxidant enzymes and perhaps stimulate GSH levels in body fluids. Recent research suggest that supplementation of certain antioxidant nutrients are necessary for physically active individuals.     

Plasma protein carbonylation and physical exercise

Regular physical activity is associated with a reduced risk of coronary heart disease, as it probably modifies the balance between free-radical generation and antioxidant activity. On the other hand, however, acute physical activity increases oxygen uptake and leads to a temporary imbalance between the production of reactive oxygen and nitrogen species (RONS) and their disposal: this phenomenon is called oxidative stress. Proteins are one of the most important oxidation targets during physical exercise and carbonylation is one of the most common oxidative protein modifications. In cells there is a physiological level of oxidized proteins that doesn't interfere with cell function; however, an increase in oxidized protein levels may cause a series of cellular malfunctions that could lead to a disease state. For this reason the quantification of protein oxidation is important to distinguish a healthy state from a disease state. Several studies have demonstrated an increase of carbonylated plasma proteins in athletes after exercise, but none have identified targets of this oxidation. Recently a process of protein decarbonylation has been discovered, this may indicate that carbonylation could be involved in signal transduction. The aim of our research was to characterize plasma protein carbonylation in response to physical exercise in trained male endurance athletes. We analyzed by proteomic approach their plasma proteins at resting condition and after two different kinds of physical exercise (PE). We used 2D-GE followed by western blot with specific antibodies against carbonylated proteins. The 2D analysis identified Haptoglobin as potential protein target of carbonylation after PE. We also identified Serotransferrin and Fibrinogen whose carbonylation is reduced after exercise. These methods have allowed us to obtain an overview of plasma protein oxidation after physical exercise.     

Vascular tone and regular physical exercise

On the basis of the results of rheovasography of the thigh region, the vascular tone was assessed using pulse transit time in subjects regularly playing sports and nonathletes with initial stages of hypertension. An increased rigidity of the vascular wall was observed in subjects with an increased blood pressure. In our opinion, vascular endothelial dysfunction is the main cause of vascular rigidity, and regular dynamic training can improve the endothelium-dependent vascular relaxation.     

Aspartate aminotransferase metabolism in muscles during physical exercise

It is established that the concentration of cytosolic aspartate aminotransferase decreases the first day after intensive physical exercises due to the intensification of the degradation processes, the decrease in the synthesis rate and the enzyme entry into the blood vessel. The enzyme content is normalized by the 24th hour of rest and then the supercompensatory phase takes place: the enzyme biosynthesis increases and its degradation decreases to a greater extent.     

Functional rearrangements in macrophages following intensive physical exercise

The effect of intensive physical exercise (swimming for 3 hours with a load of 4% body weight) on the function of hepatic, pulmonary and peritoneal macrophages has been studied in rats and mice. NBT values in alveolar and peritoneal macrophages of the experimental animals proved to be 1.5 and 1.6 times higher than in the controls. The activity of cathepsin D in the liver, lung and Kupffer cells was greater than the control values. The data obtained indicate that intensive physical exercise caused depression in phagocytic activity of Kupffer cells, the major compartment of the reticuloendothelial system, whereas a similar function in lung macrophages was even greater than in the controls and in peritoneal macrophages changed but insignificantly.     

Physiological responses to prolonged physical exercise in dogs

1. Duration of exercise until exhaustion is significantly correlated with body weight of dogs. 2. Rectal temperature (Tre) achieved at the end of the effort depends on the resting value of Tre, but the exercise-induced increases in Tre are unrelated to the initial Tre. 3. The magnitude of exercise-induced decrease in blood glucose (BG) level is positively correlated with the resting BG level and negatively correlated with the elevations of the plasma free fatty-acid (FFA) concentration. 4. A significant positive relationship is found between the exercise-induced increases in the plasma FFA levels and noradrenalinaemia.     

Muscle metabolism during prolonged physical exercise in dogs

In order to provide reference data, adenine nucleotide, creatine phosphate, glycogen, glycolytic intermediates and lactate muscle contents were measured in 49 dogs under resting conditions and during prolonged physical exercise of moderate intensity performed until exhaustion. Both the resting and exercise values of the measured variables were remarkably similar to those described in human subjects, except muscle lactate content which achieved higher values during submaximal exercise in dogs than in men.     

Severe depletion in liver glutathione during physical exercise

Physical exercise at submaximal levels in rats results in a progressive depletion of liver glutathione to about 20% of the levels found in sedentary controls which persists for several hours following the cessation of exercise. Skeletal muscle appears to be spared this severe depletion phenomenon. The levels of plasma glutathione show a transient increase at the beginning of the exercise bout followed by a linear decrease with increased running time of the animals. These results may be particularly relevant when attempting to understand the effects of physical exercise on a large number of cellular and organismal functions that are known or suspected to depend critically on the glutathione status of the liver.     

Effects of physical exercise on butyrylcholinesterase in obese adolescents

The aim of the present study was to evaluate the effect of a 12 week program of physical exercise (PE) on butyrylcholinesterase (BChE) in obese adolescents. This study compared obese adolescents (N = 54) before and after PE, regarding the relative intensity (RI) and activity of different molecular forms (G1, G2, G4 and G1-ALB) of BChE found in plasma. Waist circumference (WC) and lipid profile were also assessed before and after PE. It was shown that before PE, mean plasma BChE activity was significantly higher in obese than in non-obese adolescents and that it was significantly reduced after PE, becoming similar to that found in non-obese adolescents. Lipid profile and WC also changed in response to PE. These results are consistent with studies that found a correlation between BChE and lipid metabolism and suggest that PE may have led to a physiological regularization of plasma BChE activity. Although mean BChE activity of each isoform was significantly reduced by PE, their RI did not change. This is in accordance with a previous suggestion that this proportion is maintained under factors such as obesity, and may therefore be important for BChE functions.     

Evaluation of a standardized physical training program for basic combat training

A control group (CG, n = 1,138) that implemented a traditional Basic Combat Training (BCT) physical training (PT) program was compared to an evaluation group (EG, n = 829) that implemented a PT program newly designed for BCT. The Army Physical Fitness Test (APFT) was taken at various points in the PT program, and injuries were obtained from a medical surveillance system. After 9 weeks of training, the proportion failing the APFT was lower in the EG than in the CG (1.7 vs. 3.3%, p = 0.03). After adjustment for initial fitness levels, age, and body mass index, the relative risk of an injury in the CG was 1.6 (95% confidence interval [CI] =1.2-2.0) and 1.5 (95% CI = 1.2-1.8) times higher than in the EG for men and women, respectively. The newly designed PT program resulted in higher fitness test pass rates and lower injury rates compared to a traditional BCT physical training program.     

Comparative analysis of the effects of physical exercise

The purpose of this study was to assess anthropometrical, somatomotor, and cardio respiratory characteristics of athletes and non-athletes subjects to establish which effects of the organized physical training discriminate well between them. Subjects were 61 athlete and non-athlete medical students. Four groups were formed relying upon gender and physical activity. Body measures were computed. The motor abilities were tested by a set of static and dynamic motor tests, and cardio respiratory functions were recorded. No statistically significant differences were obtained from the comparisons of the body measures of basketball players and non-athlete medical students, except the body height. In contrast, significant differences were found both between the motor performances and between the cardio respiratory functions of the athlete and non-athlete groups. The body mass index (BMI) and the body fat (%) correlated negatively with static hanging, vertical jumping, and balance capability. On the contrary, BMI and body fat correlated positively with systolic blood pressure and vital capacity. The present results show that the effects of regular physical exercise on motor performances and cardio respiratory functions differentiate better between the athlete and non-athlete subjects than the changes in body measures.