Twelve competitive male swimmers were studied for a comparison of lactate/velocity profiles to heart rate/velocity profiles during a season of swim training. Lactate concentration (mM) and post-exercise heart rate (sum of three) after a 200-yard submaximal swim (approximately 90% of maximal attainable velocity) and a maximal swim were determined three times during the season: at the beginning (T1), after two months of training (T2) and after four months of training (T3). Both profiles demonstrated a significant rightward shift at T2 and a smaller, further shift at T3. Both lactate and heart rate significantly decreased at an absolute and relative exercise intensity in response to training. It is concluded that either parameter can be useful in monitoring training progress and for determining optimal training intensities. Because of the expense and difficulty of blood lactate measurements, heart rate/ velocity profiles can provide a practical and non-invasive alternative to blood lactate testing.

In an effort to determine the metabolic changes that occur in fatty acid oxidation during the rapid growth period, the activity of carnitine palmitoyltransferase was measured in four groups of animals at 4, 8, 12 and 16 weeks of age.Muscle samples were taken from the soleus after animals were anesthesi2ed, and the samples were assayed for CPT activity. The CPT activity was significantly higher at 4 weeks than at 8, 12 and 16 weeks (p0.0001), and the fl week activity was significantly higher that the 16 week animals. It was found that there were two distinct phases of decline in CPT activity. The first occured from 4-8 weeks where a 74% drop in activity was recorded. The second phase was a more gradual decline that occured after 8 weeks. 21% decline in activity occured between 8 and 12 weeks, followed by a 23% decrease after 12 weeks. The first drastic drop in activity can be attributed to the residual heightened enzyme concentration carried over from the suckling period in which the rat was exposed to a high fat diet found in the mother's milk. The second phase of the decline in activity is due to a dietary change which caused a shift in metabolism from fat to glucose as the primary carbon source for fuel. / School of Physical Education

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 quantify the EMG activity of selected lower limb muscles during cycling, and to define the relationship between pedal shaft width and muscular involvement. This study has particular significance to the female cyclist who by virtue of pelvic width may have a less efficient pedalling force, or an imbalance of applied muscular force. Variables analyzed were hip, knee, ankle range of motion (ROM), biceps femoris(BF), vastus lateralis(VL), rectus femoris(RF), and vastus medialis(VMO) muscle activity. Significant differences among three different pedal shaft widths were determined through use of repeated measures oneway ANOVA, Newman-Keuls post hoc test. The hip ROM, biceps femoris, and vastus medialis EKG activity results of the present study appeared to indicate that different pedal shaft widths had an effect on changes in the ROM and EMG activity. This study indicated that the hip ROM values increased with an increase in the pedal shaft width. In contary, an increase in pedal shaft width significantly decreased the muscle activity in the vastus medialis while two inch pedal shaft width significantly decreased the muscle activity in the biceps femoris. / 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).

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

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

The double product break point (DPBP) has been shown to occur in normal and cardiac subjects with values comparable to the ventilatory threshold (VT). The purpose of this study was to evaluate the intramodal and intermodal reliability of DPBP measurements during treadmill (TM) and cycle ergometry (C) exercise and to compare the DPBP to the VT. Seventeen subjects, (eight men and nine women) ages 18-60 (31.5 ± 12.4 yrs), performed four maximal exercise tests, two utilizing a standardized ramp treadmill and two utilizing an individualized ramp cycle protocol. A minimum of 48 hours separated each test. Double product (DP) was measured every 15 seconds during each test via the Kyokko Bussan CM-4001 automated blood pressure unit. Breath by breath analysis of gas exchange measurements were performed. The DPBP and VT was determined visually by three blinded observers (acceptance criteria being at least 2 observers agreeing within 10%). There were no significant intramodal differences in the V02 at the DPBP (ml'kg'1'min 1) for the two treadmill trials (23.8 + 4.9, 23.2 ±5.0) or for the two cycle trials (21.7 +7.2, 21.7 ±6.4). There was also no significant mean intermodal difference in the V02 at the DPBP for the treadmill and cycle (24.4 + 4.4, 23.1 + 5.8). Intramodal intraclass correlations for the DPBP were 0.84 and 0.79 for the treadmill and cycle, respectively. Intermodal intraclass correlation for the DPBP was 0.85. There were significant differences between the DPBP and the VT for both the treadmill (23.3 + 4.7, 28.2 ± 5.3)and the cycle (22.1 + 7.1, 27.5 ± 10.4). Correlations for the DPBP/VT comparison were 0.43 and 0.78 for the treadmill and cycle, respectively. In conclusion, results of this study suggest that DPBP measurements are reliable both intramodally and intermodally, however due to a wide range in correlations, the results suggest that the DPBP and VT are not occurring at similar V02 values. / School of Physical Education

The purpose of this study was to initiate the development of a database of values for the five-hop and vertical jump field tests for dominant and non-dominant legs in youth nine to seventeen years of age. Two hundred one youths, 102 males and 99 females, participated in all facets of the study. One trial of the five-hop test was performed on each leg and one trial was performed on each leg, then both legs, for the vertical jump test. Stature ranged from 1.41 ± 0.06 to 1.70 ± 0.07 meters for females and 1.44 ± 0.08 to 1.81 ± 0.06 meters for males. Mass ranged from 34.8 ± 4.8 to 64.3 ± 11.4 kilograms for females and 35.2 ± 10.5 to 73.1 ± 16.0 kilograms for males. Significant differences (p < 0.05) were found in dominant and non-dominant leg hops between males and females ages 12-17. Significant differences (p < 0.05) were found in dominant leg vertical jumps between males and females at ages 12-14 and 16-17 and in non-dominant leg vertical jumps at ages 12, 16 and 17. Twelve year olds had a significant difference (p < 0.05) between males and females when dominant leg hop distance was normalized to mass. When comparing non-dominant hop distance to dominant hop distance, significant differences (p < 0.05) were found between males and females 15 years of age. Values obtained for this ratio agree with the literature for adult hop ratios and suggest that limb asymmetry/deficiency determination be set at 0.85 for youth. / School of Physical Education