Wayne D. Van Huss

Effects of an anabolic steroid and sprint training on selected histochemical and morphological observations in rat skeletal muscle types

SummaryThe effects on selected histochemical and morphological parameters of anabolic steroid administration and of high-intensity sprint running, separately, and in combination, were studied in young adult male rats. Dianabol (methandrostenolone) 1 mg/day for 8 weeks had no significant effects on phosphorylase or glycogen staining intensities and on fiber area in skeletal muscles of either trained or sedentary animals. The program of sprint training resulted in significantly decreased intensities of phosphorylase in all ten regions of the gastrocnemius, plantaris, and soleus muscles that were studied. Glycogen localization was significantly increased with training in five regions of the gastrocnemius and plantaris muscles which contained predominantly fast-twitch fibers. No changes in fiber area occurred with the training program. We conclude from these results that (a) normal androgen levels in young, healthy male animals are sufficiently high so that the intake of large doses of anabolic steroid does not result in the stimulation of glycogen metabolism or hypertrophy of skeletal muscle; (b) the changes induced by high-intensity, short-duration sprint training suggest that the existing glycolytic capacity of muscle is adequate to supply the muscles energy needs even during the stress of very strenuous exercise, and that more fast-twitch fibers were recruited by the exercise regimen than slow-twitch fibers.

Somatotype and Longevity of Former University Athletes and Nonathletes

A longitudinal study was conducted on 398 athletes and 369 nonathletes who were born before 1920 and attended Michigan State University. The subjects were compared to determine if intercollegiate athletic competition accounts for significant variation in longevity when considered with somatotype. Because some of the subjects were still alive at the time of the study, the BMDP Statistical Software was used to do a survival analysis with covariates. Preliminary comparisons considered the differences in somatotype between athletes and nonathletes. Two sample t-tests indicated that athletes were more mesomorphic and less ectomorphic (p less than .05) than nonathletes. When comparing the relationship between somatotype and longevity, the pooled data of athletes and nonathletes indicated that endomorphs were shorter lived than the other three comparison groups. When only the athletes were considered, similar results were found. However, the nonathlete group exhibited differences only between the mesomorphic and endomorphic groups. The endomorphs were shorter lived. Longevity was examined by using the Cox proportional hazards regression method with somatotype and athlete/nonathlete status as covariates. Somatotype, by itself, was found to be significantly related to longevity, (p less than .001). Athletic status was not significantly related to longevity, either by itself or when entered into the model with somatotype.

Effects of Forced Exercise upon the Amount and Intensity of the Spontaneous Activity of Young Rats

Abstract This experiment was made to determine the effects of a mild prepuberty forced exercise upon the amount and intensity of the spontaneous activity of young male albino rats. Forty-five male Sprague-Dawley rats 33 days old, were divided into three equal groups: control, forced exercise, and sedentary. The study was conducted for 264 consecutive days with the first 35 days a treatment phase, the following 35 days an immediate post-treatment phase, and the remaining 194 days a follow-up phase. Treatments consisted of forced exercise by swimming with mild overload or sedentary existence. Results indicated that rats forced to exercise by swimming ran significantly more revolutions at a significantly faster rate of speed and with greater distance each run during an immediate post-treatment phase than animals of control and sedentary groups. The longer the period from the forced exercise treatment, the more reduced was the spontaneous activity until at termination the control level was reached.

An investigation of the Müller-Franz calorimeter

Summary2 aspects of the Müller-Franz dry gas meter were investigated; namely, accuracy of metering and mechanical resistance of the apparatus. The first problem was investigated by pumping known volumes of gas through the meter at varying rates of flow; the second by measuring the resistance in the air circuit by means of a water manometer. The Müller-Franz apparatus, based upon the study of 6 instruments, appears to underestimate gas flow. If a correction factor is applied to account for this, the meter is accurate to approximately plus or minus 3 or 4% between rates of flow of approximately 3 to 100 l/min. The resistance of the mechanical operation of the meter amounts to 20–25 mm water at about 50 l/min and to about 40–50 mm water at approximately 100 l/min.

Histochemical and morphological observations on rat myocardium after exercise.

Effects of seven levels of chronic physical activity on the metabolic and morphologic characteristics of left ventricular myocardium of adult male albino rats were investigated.Treatments included sedentary control; voluntary running; short-duration, high-intensity running; medium-duration, moderate-intensity running; long-duration, low-intensity running; electric stimulus control; and endurance swimming. Excluding the controls, the animals were trained 5 days per week for 8 consecutive weeks. Food and water were providedad libitum to them. Fifty-six animals comprised the final sample.Histochemical techniques were used to evaluate the relative glycogen, fatty acid, SDH and LDH concentrations in the cardiac fibers. Each stain was measured objectively, using a photometer. A Hematoxylin and Eosin stain was employed to rate morphologic features. These sections were evaluated subjectively on the basis of presence or absence of lesions.Physical training for 8 weeks was sufficient to produce metabolic adaptations in the rats. The trained animals gained 37.4 % less body weight than did the sedentary controls (P < 0.05). However, neither histochemical nor morphological changes had occurred to the hearts of these animals consequent to the 8 weeks training programs. Apparently, the myocardial tissues examined, from the trained animals, contain the enzymes, SDH and LDH, and the substrates, glycogen and fatty acids, in amounts greater than that needed to cope with the exercise stress afforded by these training programs.

Effect of Milk Consumption on Endurance Performance

Abstract Nine trained trackmen were divided into experimental (nonmilk) and control (milk) groups. Both groups participated in eight weeks of training. The experimental group was not permitted any milk, cheese, or ice cream except in those dishes in which milk was used in cooking. The controls consumed a minimum of three pints of milk daily and about two pints of ice cream each week. Steady state and all-out treadmill measures were obtained as well as diet recall records. During the period of this investigation no significant effects which might be attributed to milk were observed on performance. With exclusion of milk from the diet the intake of calcium, vitamin A, and riboflavin dropped significantly and below the recommended minimum allowances.

Effects of Prepubertal Forced Exercise Upon Postpubertal Organ and Body Weights of Female Rats.

Abstract One-hundred-fifty female rats were used in this study of the immediate and residual effects of prepubertal exercise upon organ and body weights. Animals were randomly assigned to 3 initial treatment groups: sedentary (S), voluntary (V), and voluntary plus forced exercise (V+F). Forced exercise consisted of 35 daily 30-min. swims with a tail weight of 2% of body weight. Two treatment periods were given, one just before puberty and another after 165 days of intervening voluntary activity. Sacrifices occurred posttreatment I, pretreatment II, and posttreatment II. Both (V) and (V+F) animals had lower body and absolute spleen weights but higher relative adrenal, heart, and liver weights than the controls. The absolute spleen and relative adrenal differences remained pretreatment II. Posttreatment II, lower body and absolute spleen weights were noted in (V) than in (S) groups. Although several significant interactions between treatments I and II were observed, only the lower body weight of active anim...

Effects of Milk and Training on Swimming Performance and Organ Weight in Rats

Abstract Three groups of litter mate albino male rats were utilized as follows: Group A received a stock diet and was forced to swim daily; group B was subjected to the same exercise but the diet was such that 30 percent of the caloric intake came from powdered whole milk; group C was given the stock diet but no exercise. The experiment continued for 12 weeks after which the animals were forced to swim as long as they were able. Several days later the animals were sacrificed and organ weights determined. Replacing a portion of the stock diet with milk appeared to have no effect on body weight, endurance performance, or weight of the heart, kidneys, spleen, adrenals, liver, or testes. When the exercised animals were compared with the sedentary ones, the daily swimming program was seen to result in significant increases in swim time, carcass specific gravity, and heart and adrenal weight and a significant decrease in body and spleen weight. Endurance swimming time appeared to be unrelated to the various org...

Reversal of the energy metabolism responses to endurance training by weight loading.

6 university team distance runners were randomly placed into experimental and control groups to determine the effect of progressive overloading with weights upon selected training responses. Both groups received identical training for 8 wk. with the exception that three days each week the experimental Ss wore weighted wristlets, anklets, and belts. Pre- and posttest energy metabolism measures were taken during and following both a low-intensity 15-min. run (9.7 km/hr, 0% grade) and a high-intensity run to exhaustion (16.1 km/hr, 9% grade). The energy metabolism responses to endurance training were significantly reversed by the progressive overloading with weights. The energy cost of the low-intensity run was increased and an unexpected shift toward greater anaerobic metabolism was observed.