Access to abstract is permanently restricted to Ball State community only / Access to dissertation permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science

This study investigated differences in heart rate recovery (HRR) and the underlying autonomic mechanisms following maximal and submaximal exercise between boys and men. Children are known to have a faster HRR than adults. However, the mechanism responsible for these differences is still largely unknown, but is thought to be due to differences in the autonomic nervous system. Ten boys (10.1 ± 0.8 years old) and ten men (24.2 ± 1.3 years old) completed a supine recovery following a maximal and submaximal exercise bout. HRR was measured as the decline in HR during the first minute of recovery and heart rate variability (HRV) was used to measure autonomic function. Boys had a faster HRR during the first minute of recovery from maximal exercise (p<0.05), but there was no difference in HRR following submaximal exercise (p>0.05). The R-R coefficient of variation and high frequency power were both significantly greater following maximal exercise in boys than men. There were no differences in HRV variables following submaximal exercise. These findings suggest that faster parasympathetic re-activation could be a mechanism responsible for faster HRR in boys compared to men, especially following maximal exercise. / School of Physical Education, Sport, and Exercise Science

The purpose of this study was to examine the fibrinolytic response to whole body vibration (WBV) and exercise in men. Methods. Twenty healthy males (23.8 ± 4.2 years, 80.8 ± 3.3 kg·mˉ²) participated in the study. Each subject performed 3 trials in randomized order separated by 1 week. The trials consisted of exercise (X), vibration (V) and vibration + exercise (VX). Exercise sessions consisted of 15 minutes of unloaded squatting at a rate of 20 per minute. Vibration sessions were conducted on a WBV platform vibrating at a frequency of 30 Hz and amplitude of 1.5mm for 15 minutes. Plasma concentrations of active tPA and PAI-1 samples were assessed at baseline and immediately after each session. Results. tPA activity change from pre to post trial was found to be significantly greater in the VX condition (0.87 ± 0.35 IU·mlˉ¹ to 3.21 ± 1.06 IU·mlˉ¹) compared to the X (0.71 ± 0.36 IU·mlˉ¹ to 2.37 ± 1.13 IU·mlˉ¹) or V (0.83 ±0.25 IU·mlˉ¹ to 1.00 ± 0.37 IU·mlˉ¹) condition. tPA activity change from pre to post trial was found to be significantly greater in the X condition compared to the V condition. PAI-1 activity change from pre to post trial was found to be significantly decreased in the VX (6.54 ± 5.53 IU·mlˉ¹ to 4.89 ± 4.13 IU·mlˉ¹) and X (9.76 ± 8.19 IU·mlˉ¹ to 7.48 ± 7.11 IU·mlˉ¹) conditions compared to the V (5.68 ± 3.53 IU·mlˉ¹ to 5.84 ± 3.52 IU·mlˉ¹) condition. Heart rate change from pre to post exercise for the V condition (pre, 75 ± 8 bpm; post, 90 ± 7 bpm) was less than the change in the VX condition (pre, 77 ± 13 bpm; post, 148 ± 19 bpm) and X condition (pre, 71± 11 bpm; post, 139 ± 22 bpm). The change in heart rate was found to be similar in the X and VX conditions. Peak RPE was not significantly different between X and VX sessions. Conclusions. WBV does not stimulate increased fibrinolytic activity in young men. However, the significant increase in fibrinolytic potential observed during squatting exercise is enhanced by concurrent WBV. / School of Physical Education, Sport, and Exercise Science

Trained male cyclists (6 in study 1, 5 in study 2) cycled to exhaustion (EXH) at 75% of VO₂ max twice; once in the non-supplemented (NS) state and once in the vitamin B-6 (B-6)(20 mg PN) supplemented (S) state. The diet contained 2.3 mg B-6 in study 1 and 1.9 mg B-6 in study 2. Urine was collected during each dietary period. During each exercise (EX) test, blood was drawn prior to (PRE), one hour during (DX), immediately after (POST) and one hour after (POST 60) EX and sweat was collected. Compared to baseline (PRE) levels, plasma pyridoxal 5'-phosphate (PLP) and vitamin B-6 (PB-6) concentrations increased at DX, decreased at POST, and decreased below PRE at POST 60 in the NS and S states. EX to EXH in the S state resulted in a greater increase in PLP DX in study 1 (31% increase vs. 16%) and PB-6 in study 2 (25% increase vs. 11%) as compared to the NS state. Red blood cell (RBC) PLP significantly increased from POST to POST 60 in the S state in study 2. The excretion of urinary 4-pyridoxic acid (4-PA) and urinary B-6 (UB-6) was not significantly altered by EX to EXH. The mean excretion of 4-PA was significantly greater in the NS state in study 2 (7.98 ±1.83 mmol/d) as compared to the excretion in study 1 (6.20 ±0.93 mmol/d), whereas the excretion was significantly greater in the S state in study 1 (92.2 ±8.69 mmol/d) compared to the excretion in study 2 (82.7 ±6.16 mmol/d). The percent of B-6 intake excreted as UB-6 (6% in study 1 and 10% in study 2) was significantly different between the studies in the NS state. Vitamin B-6 supplementation did not significantly alter the rise in growth hormone (hGH) concentration seen with EX to EXH. The loss of B-6 in sweat with EX to EXH was not altered by B-6 supplementation. The loss of B-6 in sweat ranged from 0.0011 mmol to 0.0039 mmol. Therefore, EX to EXH in the B-6 S state resulted in a greater increase in plasma PLP and PB-6 DX as compared to the NS state. The decrease in PB-6 and PLP at POST 60 in the S state coincided with a significant increase in RBC PLP, suggesting the movement of B-6 from the plasma into the RBC at POST 60. EX to EXH and B-6 supplementation did not alter the excretion of 4-PA or UB-6 suggesting that B-6 metabolism was unchanged. The loss of B-6 in sweat was comparable to previously reported values and was not altered by B-6 supplementation. B-6 supplementation did not alter the changes in hGH resulting from EX to EXH alone. / Graduation date: 1995

Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science

The purpose of this study was to compare selected kinematic characteristics of distance runners over a twenty year period. The subjects in the investigation were 14 long distance runners who at the time of the first observation were considered highly trained (running more than 50 miles per week). The second observation occurred approximately 20-23 years after the first observation. At this time the average weekly mileage per runner had decreased to 37 miles per week. The first observation's data were collected with a Locam camera at film speeds ranging from 60 to 120 frames/second. The film data were digitized at the same time as the second observation's data. The second observation's data were collected with a Panasonic 5000 shutter video camera. The Peak Performance Motion Measurement System video interface allowed a 60 frame/second field rate. Ten subjects ran at a speed of 3.4 m/s; two subjects at the speeds of 3.1 and 3.6 m/s; and one subject at each of the following speeds: 4.0, 4.5, and 4.9 m/s. Statistical analyses (ANOVA) of the stride length, stride frequency, support and non-support time, and joint angular displacement indicated no significant difference (p > .05) between the first observation and the second observation. The results of this study indicated that the kinematics of continually active long distance runners do not change with an increase in age. / School of Physical Education

This study examined the physiological and perceptual effects of carbohydrate (CHO) on variable-intensity exercise (VIE) in boys and men. It was hypothesized that CHO would increase RER in boys and men and that this increase would be greater in boys. Additionally, it was hypothesized that RPE would be attenuated by CHO. Five boys (10-12 years) and seven men (18-30 years) consumed CHO or a placebo (PL) beverage before and throughout VIE. VIE included three 12-min sets of cycling; intensity varied every 20-30 seconds between 25, 50, 75, and 125% VO2max. Boys’ post-exercise glucose was higher in the CHO trial than the PL trial and RER was lower in boys than men, but was not affected by trial. RPE increased over time but was not different between groups or trials. Though VIE responses varied between boys and men, CHO ingestion before and during VIE did not provide physiological or perceptual benefits. / School of Physical Education, Sport, and Exercise Science

Progressive resistance training (PRT) in the elderly has commonly used ATPase histochemistry to evaluate fiber type changes, but evidence shows there are myosin heavy chain (MHC) hybrids in aging muscle that cannot be classified by histochemistry. The purpose of this study was to assess the MHC and whole muscle alterations following a 12-week PRT protocol. Seven healthy men (age=74.0±4.7, weight=74.6±13.5kg) underwent testing for 1-repetition maximum (1-RM), whole muscle (thigh) crosssectional area (CSA) by computed tomography, and a needle muscle biopsy from the vastus lateralis for analysis of MHC, pre- and post-training. The PRT consisted of 2 sets of 10 repetitions, and a third set to volitional exhaustion at 80% 1-RM, 3 days per week for 12 weeks. Muscle ATPase histochemistry analysis for distribution did not significantly differ following training. Muscle samples were freeze dried and dissected for MHC analysis (sodium dodecyl sulfate-polyacrylamide gel electrophoresis (5% gel) and silver stained; 224.0±11.2 and 213.0±8.1 fibers/subject pre-/post-training; total fibers analyzed=3059). MHC analysis demonstrated significant increases in MHC I proportion (10.4%; P<0.05), and significant decreases in MHC UIIa (9.0%; P<0.05), UIIa/x (0.9%; P<0.05), and IIa/x (8.9%; P<0.05) isofroms, along with no change in the MHC Ila and IIx isoforms, pre- versus post-training. In addition, 1-RM (51.9%; P<0.05) and CSA (5.9%; P<0.05) increased from pre- to post-testing. This data supports previous whole muscle changes, more important, is the increase in MHC I and decrease in MHC I/IIa, I/IIa/IIx, and IIa/x hybrids. The myosin light chain 3f (MLC3f) to MLC 2 ratio did not change with the PRT in either the MHC I or MHC IIa isoforms, although there was a significantly greater amount of MLC 3f in the MHC Ila versus the MHC I fibers (p<0.05), pre- and post-training. The myosin isofrom data provides support that aging muscle has the plasticity to adapt in a manner unlike that of young muscle. / School of Physical Education

This study examined the influence of maturation on the oxygen uptake efficiency slope (OUES) in healthy male subjects. The variables comprising the OUES are known to be affected by metabolism which in turn is influenced by maturation. The subjects performed a graded exercise test on a cycle ergometer to determine the OUES and VO2max. Subjects were divided into groups based on maturation status: early-pubertal (EP, n = 15), mid-pubertal (MP, n = 20), late-pubertal (LP, n = 17), and young-adult (YA, n = 19) males. Cardiorespiratory fitness (measured as VO2max mL·min-1·kg-1) was not significantly different between groups. OUES values in absolute terms were higher in groups LP and YA versus MP and EP. Scaling OUES relative to body mass failed to eliminate between group differences whereby LP and YA had lower mass relative OUES values compared to LP and YA. Scaling OUES relative to fat free mass also failed to eliminate between group differences with EP group values being higher versus LP and YA, but only MP values being higher than YA. Differences in OUES values between male across maturation status remained after accounting for differences in body size, suggesting an affect of maturation on this measurement. / School of Physical Education, Sport, and Exercise Science

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