This study examined the effects of exercise on glucose metabolism in adipocytes from female rats. Female rats were exercised by swimming six hours per day, five days per week for eight weeks. There was no variation in body weight gain (P > 0.05) between the exercise and control animals through the experimental period. The swimmers' fat cells were smaller (P < 0.05) than those of the sedentary controls of the same age. The rates of glucose oxidation of both C-1 and C-6 glucose were significantly higher (P < 0.05) in the exercise rats' adipocytes at all insulin concentrations. The sedentary control rats' adipocytes showed no significant response at any insulin concentration. Thus, exercise is a significant stimulus to cause increased oxidation rates in the adipocytes from exercising rats. These data also indicate that glucose transport, not defective glucose oxidation, is the limiting mechanism that accounts for the decreased responsiveness of adipocytes from sedentary control animals.

The purpose of this study was to determine effects of diet composition and exercise on the loss and maintenance of loss of body weight and body fat; and the protection of muscle in obese subjects. Ten subjects who were members of the Ball State University (BSU) Adult Fitness Program and/or the BSU Weight Management Program, and who were at least 120 percent of ideal body weight, participated in the one-year study.Three-day diet records collected at four-month intervals were assessed using the Nutriplanner computer data base to determine energy and nutrient composition of subjects' diets. Measures of weight, triceps skinfolds (TSF), and arm circumference were collected at three-month intervals to assess changes in weight, arm fat area (AFA), and arm muscle area (AMA). Adherence to exercise was reported by participants.The findings of this study showed that obese subjects who consumed low-fat, high-carbohydrate diets while adhering to an exercise program lost, or tended to lose, more weight and arm fat area, while experiencing an increase in arm muscle area. Further studies in this area of research are needed to assess the effects of diet composition, exclusive of exercise, on changes in fat and muscle area. In addition, work is needed to develop more reliable means of assessing food intake over an extended period of time.

This study was desined to measure the effect of various intensities of leg-press exercise and squat exercise on hGH release. Young, 24 ± .7 yrs of age, male lifters (n=3) served as subjects for this study. After a 1 RM was established on the weight sled and squat rack they completed a 3 RM, 10 RM, or 25 RM workout using a 3 set protocol. Each workout (3, 10, squat exercises were separated by 2 weeks. Blood was taken from an antecubital vein prior to exercise (pre-exercise, after warm-up, and post-exercise 4, 8, 16 MIN). The serum was measured for hGH levels. The results indicate that 1) High intensity exercise of a short duration will not elicit a hGH response indicating that exercise duration is more important than exercise intensity, 2) The hGH output, in part, depends on exercise intensity when exercise duration is sufficient to elicit hGH response, and 3) The increased lactic acid during resistance exercise did not relate to hGH levels. / School of Physical Education

The purpose of this study was to determine the effects of an upper respiratory illness (URI) on running mechanics during a maximal VO2 exercise treadmill test. The specific measurements assessed were stride length (SL), stride frequency (SF), range of motion (ROM) of the hip, knee, and ankle, and the displacement of the center of mass (COM) during the stride cycle. Fifty-three subjects (female=25, male=28) between 18 and 30 years of age completed the study. The participants in the study were characteristically non-smokers, drank fewer than five alcoholic drinks per week, had no orthopedic problems, were not pregnant, did not suffer from hay fever or chronic colds, and were not allergic to penicillin. Rhinovirus Type 16 was used in the inoculation of the individuals. The subjects performed two maximal V02 treadmill test. The first test was before the inoculations and the second test was during the height of the illness. Stride length and SF data were derived from accelerometer data. Statistical analysis using ANOVA revealed no significant changes in SL or SF between pre- and post-inoculation treadmill tests. Based on the results of this study it was concluded that Rhinovirus Type 16 does not effect running mechanics during a maximal V02 treadmill test. / School of Physical Education

Young female Sprague-Dawley rats ( 50 gm., body weight-BW) were conditioned to treadmill activity (13.4 m•min -1; 0% grade) over a 12 d. period and then randomly assigned to groups combining exercise (E) and diabetes (D) with appropriate normal-sedentary controls (Sd). The diabetic condition was induced by I.V. injection of Streptozotocin (70 mg/kg BW) in citrate buffer and was evidenced by hyperglycemia (>330 mg. glucose/dl), polyuria and polydipsia. The E program was conducted 6 d./wk. Intensity and duration were progressively increased and reached 20% grade at 26.8 m•min-1 with 45 sec. sprints at 40.2 m-min-1 at 5 min. intervals. Total daily E time reached 60 min. for 8 wks. of training at which time experimental and appropriate control animals were sacrificed. Paramenters studied included in vitro capacity of slow oxidative (SO), fast oxidative. glycolytic (FOG), and fast glycolytic (FG) tissues to oxidize (Q02) pyruvate and palmitate. A 2x2 factorial ANOVA was used to detect E/Sd (Factor A) effects, D/non-D (Factor B) effects, and interaction (AxB) effects. A Student-Newman-Keuls multiple range test was employed to determine which experimental groups differed from each other. Results indicate a complex interaction of treatment effects depending upon muscle type. For the most part, E resulted in a reduction or modification of U effects. The DE group was not significantly different from either Sd or E controls for pyruvate 002 for all 3 muscle types. However, DS was significantly depressed below DE and controls for SO and FG tissues (pyruvate Q02). For palmitate 002 DE was significantly greater than both DSd and CSd groups for FOG tissue, (3244μ a 02/hr./gm vs. 2538 and 2555μl 02/hr/gm). Also both DE and CE were greater than both Sd groups for FG tissue (1925 and 1664μl 02/hr/gm vs. 1352 and 1283μ1 02/hr/gm, respectively). There were no significant differences between groups for SO tissue (palmitate Q02).

Plasma choline levels have been reported to be significantly reduced in athletes at the endof prolonged, exhaustive exercise (marathon running), and this may affect the release of acetylcholine at the neuromuscular junction (16). The purpose of the present investigation was to examine the influence of two levels of choline (from soy lecithin) ingestion on plasma choline levels and exercise performance. Ten endurance-trained male cyclists exercised on an electrically resisted ergometer for 105 minutes at a load equal to 70% V02 max, followed by an all-out, self-paced 15 minute performance ride on an isokinetic cycle. Three randomly ordered trials were performed four hours after the feedings of (A) 0.0 g, (B) 1.1 g, or (C) 1.8 g choline. Dietary intake of choline was controlled. Before and after the trials, blood samples were drawn and analyzed for serum choline (umol/liter) using an HPLC method. Feedings of 1.1 g and 1.8 g of choline significantly (p < 0.05) elevated serum choline values compared to control (A = 34.16 [± 0.63], B 38.17 [+ 0.96], and C = 42.32 [+ 0.59]).Post-exercise serum choline values, however, were not significantly different (p > 0.05) from pre-exercise levels. In addition, there were no significant differences (p > 0.05) in performance between placebo, 1.1 g, and 1.8 choline trials (2.11 x 105, 2.07 x 105, 2.07 x 105 Newton-meters, respectively). This study indicates a dose response to choline ingestion, with no effect on performance. / School of Physical Education

Oxygen consumption remains elevated above resting values for a variable period of time after exercise. Exercise intensity and duration, food intake, laboratory conditions, metabolic measurements, gender and age are all major factors affecting the duration and magnitude of excess post-exercise oxygen consumption (EPOC). In the present study, the influence of age on EPOC was studied in men of various fitness levels. Various metabolic measurements were collected for three distinct age groups, 18-25, 35-45, and 55-67 at rest and during exercise at 60% of maximal oxygen consumption until 200 ± 10 kilocalories were expended. Immediately after the exercise bout, subjects walked on the treadmill for one minute and then were seated until oxygen consumption returned to within .01 liters of the recorded resting values.Percent body fat, V02 max and exercise V02 were significantly different between age groups. The duration (23-25 minutes) and magnitude (7-11 kilocalories) of EPOC did not differ significantly between groups. However, heart rate and minute ventilation were significantly elevated above resting measurements when V02 reached resting values. In conclusion, the physiological differences associated with the aging process were not found to significantly affect the duration and magnitude of EPOC. / School of Physical Education

The ventilatory threshold (VT) is measured frequently during graded exercise tests (GXT) for exercise prescription purposes. The computerized V-slope method for VT determination has been reported to be valid yet little data exists concerning the reliability of the measure. The purpose of this study was to determine the reliability of the VT using the computerized V-slope method. Sixteen healthy volunteers, (eight men and eight women) ages 21-27 (23.6 ± 1.7yrs), performed three maximal GXT on an electronically-braked cycle using an individualized ramp protocol. A minimum of 48 hours separated each test; all three tests were completed within two weeks. Breath-by-breath analysis of gas exchange was performed using a SensorMedics 2900 cart. The VT, expressed as L • min1, was selected by a computerized V-slope method. There were no differences in V02 max between the 3 trials, (overall mean 3.18 ± 0.87 L - min-1). No significant differences were observed for V02 at VT (L - min-1) for tests 1, 2, and 3 (1.62 ± 0.44, 1.58 ± 0.49, and 1.49 ± 0.48) respectively. The VT was determined to be 49.7 ± 7.9% of V02 max. Correlations between the VT in trials 1-2, 1-3, and 2-3 were 0.829, 0.791, and 0.925, respectively. The overall coefficient of variation (C.V.) of the VT measures was 10.61 ± 5.1%. The overall (male and female) variability in VT was 1.28 ± 0.63 METS. Due to high variability and a wide range in correlations, the results failed to support the reliability in the computerized V-slope method. / School of Physical Education

Viral illnesses are the most common agents affecting humans. Due to their widespread affects, viruses may have a particular influence on exercise functional capacity. Therefore, the purpose of this study was to determine the impact of an Upper Respiratory Infection (URI) on exercise functional capacity, as measured by VO2max. In addition, submaximal exercise responses, changes in resting pulmonary function, the impact of select symptoms, and level of initial fitness on performance during an URI were also determined. Forty-five subjects (females=21, male=24) between 18 and 29 years of age participated in this study and were assigned to a mild or severe illness group based on symptom severity. There was also a control group of 10 subjects (female=5, male=5). An initial serological screening was performed on all experimental subjects to assess for the RV16 antibody.Subjects testing negative for the antibody performed a baseline graded exercise test to volitional fatigue, as well as pulmonary function tests. Each subject was inoculated two consecutive days with the RV16 virus within ten days of the baseline exercise test. The day following the second inoculation (peak illness) the subjects performed post-pulmonary function and exercise tests. The control subjects performed two resting pulmonary function and exercise tests separated by one week. Significance was set at p<0.05. Repeated measures ANOVA revealed a significant interaction in V02 at submaximal and maximal levels between trials for all groups (p<0.045). A significant interaction for VE for all levels and all groups was found (p<0.002). No impairment in resting pulmonary function was observed. Analyses of symptoms, and initial V02 in regard to performance, also revealed no significant differences. Therefore, the results seem to indicate that an URI does not limit one's ability to perform at submaximal or maximal levels of exercise, however, some relationship seems to exist. Further research is needed to clarify the effects of an URI on physical performance. / School of Physical Education

Exercising at an appropriate training intensity for individuals is important for improvement of cardiorespiratory fitness. The American College of Sports Medicine (ACSM) has recommended that healthy adults exercise at an intensity of 60-80% maximal heart rate reserve (MHRR). The ventilatory threshold (VT) has also been recommended for use to determine intensity for exercise prescription. The purpose of this study was to compare the heart rate at the VT (VTHR) and at 60-80% MHRR. A secondary purpose was to determine the relationship, if any, between age, gender, height, weight, body mass index, percent body fat, resting heart rate, physical activity status (PAS), smoking history, and rating of perceived exertion (RPE) at 60 and 80% Hrmax and the difference between the VTHR and 60% MHRR. Subjects were 373 apparently healthy or high risk (as defined by ACSM, 2) individuals (209 men, 164 women), ages 19-77 (46.1+12.8 yr.), from the Ball State University Adult Physical Fitness Program who performed a maximal treadmill test between 1992-1994. VT was selected using a computerized V-slope method by the SensorMedics 2900TI Metabolic Measurement Cart. The VTHR (125.2+16.9) was significantly lower than the 60-80% MHRR (133.1+10.8 to 154.5+12.7) (p<0.05). Two hundred and sixty two subjects (70.1%) were below 60% MHRR and 3 subjects (0.8%) were above 80% MHRR at the VTHR. Multiple regression analysis explained 11.2% of the variance in the difference between the VTHR and 60% MHRR using RPE at 60% HR,,,, PAS, and smoking history. For the majority (70.2%) of the adults in this study, the VTHR falls below the traditional THR of 60-80% MHRR. The 60-80% MHRR would appear to be an appropriate exercise training intensity for cardiorespiratory benefit and therefore the %MHRR range alone would seem to be an adequate training intensity. Further study related to the VTHR is warranted to determine its application, if any, to exercise prescription intensity. / School of Physical Education