Master of Science / Department of Kinesiology / Steven W. Copp / Cancer patients have a reduced exercise capacity compared to age-matched healthy counterparts which contributes to premature fatigue. The reductions in exercise capacity are multifactorial and vary depending on the type of treatments and the specific cancer. Given that cancer treatments have been shown to impair cardiovascular and/or skeletal muscle function, it is difficult to determine if cancer itself reduces exercise capacity. We used a rat prostate tumor model to test the hypothesis that cancer independently reduces endurance exercise capacity. Methods: In male Copenhagen rats (COP/CrCrl), an initial treadmill test to exhaustion was used to determine endurance exercise capacity. Subsequently, the prostates of the rats were injected with either prostate carcinoma cells (R-3327 AT-1) in Matrigel (cancer: n = 9) or Matrigel only (sham: n = 7). Treadmill tests to exhaustion were repeated four and eight weeks post-surgery. Results: Time to exhaustion decreased over the course of the experimental protocol in both the sham and cancer groups. However, the overall reduction in time to exhaustion in the cancer group (-16.7 ± 1.9 min) was significantly greater (p = 0.038) than the sham group (-10.1 ± 2.2 min). Despite no differences in total body mass at the end of the experimental protocol, heart, left ventricle, and gastrocnemius muscle mass were significantly lower in the cancer group compared to the sham group (p < 0.05 for all). Moreover, within the cancer group heart and left ventricle mass, but not gastrocnemius mass, were significantly inversely correlated with prostate tumor mass. Conclusion: Endurance exercise capacity was reduced in rats with untreated prostate cancer to a greater extent than it was reduced in sham operated rats. Although multiple mechanisms likely contributed to the reduced exercise capacity, reductions in heart and gastrocnemius muscle mass likely played an important role.

Exposure to natural altitude using the "live high-train low" method improves athletic endurance performance at sea level by 1-2%. This method can also be employed with hypoxic devices that simulate altitude, but there is limited and conflicting research on their efficacy. Consequently, three studies were undertaken to investigate changes in sea level performance of endurance runners following exposure to altitude simulated with hypoxic tents. The device was chosen because of its potential for incorporation into the athlete's routine. In Study 1, 10 runners received altitude simulated with hypoxic tents (~9 h overnight at 2500-3500 m) and trained at sea level, while 10 runners in the control group performed usual training. Athletes in both groups performed a lactate-threshold test, but only the altitude group performed a run to exhaustion. The effect on 4-mM lactate speed was unclear, owing to poor reliability of this measure. There was a 16% increase in time to exhaustion in the hypoxic conditioning group, equivalent to a 1.9% (90% likely limits, ±1.4%) increase in speed in a time trial. Effects on performance were not apparent four and eight weeks after use of the tents. To improve precision of the effect of the tents and to determine the effects on performance of different durations, a further controlled trial was performed. A reliability study (Study 2) was first conducted to investigate the potential for runs to exhaustion to provide reliable measures of performance. Eight runners performed a test consisting of three runs to exhaustion lasting ~2, ~4 and ~8 min on six occasions over 14 wk. The critical power and log-log models were used to provide factors for converting variability in time to exhaustion into variability in equivalent time-trial time. Variabilities in time to exhaustion expressed as coefficients of variation for predicted 800-3000 m timetrial times were ~1-3%. A crossover study (Study 3) was then conducted in which 11 athletes performed usual (control) training and usual training with altitude exposure by using tents for 25 ± 3 days (mean ± SD) for 8.1 ± 0.6 h.d-1, progressing from a simulated altitude of 2500 m to 3500 m above sea level. Washout period between control and altitude treatments was four weeks. Performance was assessed with treadmill runs to exhaustion as in Study 2. Improvements in mean predicted times (altitude-control) for standard competition distances of 800, 1500 and 3000 m derived from the runs to exhaustion were 1.0% (±1.3%), 1.4% (±1.2%) and 1.9% (±1.5%) respectively. There was some evidence that hypoxic exposure favoured those athletes carrying the I allele for angiotensin converting enzyme. In summary, the main finding from the series of studies is that hypoxic tents are likely to enhance sea level endurance running performance by ~1-2%.

The optimisation of strength and power through resistance training has been the source of debate amongst health professionals and researchers for many years. As resistance training involves the repeated activation and contraction of skeletal muscles, continuous training will ultimately result in a failure to sustain the training intensity especially when performing multiple sets and / or repetitions. Therefore the prescription of rest periods within the training session becomes an important consideration. Relatively short rest periods (60-90 seconds) have been traditionally used for the maximal strength adaptation involving increases in the cross-sectional area of the muscle, whereas longer rest periods (180-300 seconds) have traditionally been used for the maximal strength adaptation involving enhancement of neural function and maximal power adaptation. However, there is very little scientific evidence to support these current practices. In fact, the effect of different rest periods on maximal strength and power development has received very little research attention. Additionally, research that has been conducted in this area has been typified by a number of methodological inconsistencies, within and between studies, which confound scientific understanding. Although traditionally resistance training has employed continuous training schemes with inter-set rest periods, intra-set rest training methods which distribute rest intervals between groups of repetitions have also been investigated. It has been theorised that the short rest periods within the training set allow partial resynthesis of the intramuscular phosphocreatine stores, potentially allowing an athlete to increase their training volume by training at high intensities for longer durations, or performing additional repetitions (Berg, 2003). This is thought to lead to an increased exposure of the muscle to the kinematic and kinetic stimuli thought important for strength and power adaptation whilst minimising performance-inhibiting metabolic accumulation and substrate depletion. However, research into intra-set rest training schemes is still in its infancy, and many of the theories surrounding intra-set rest training are currently unsubstantiated. It is thought that examinations of the acute kinematic, kinetic and blood lactate profiles of continuous and intra-set rest training schemes may enhance scientific understanding regarding the efficacy of intra-set rest training. The purpose of this study was to investigate and compare the acute kinematic, kinetic and blood lactate responses to continuous and intra-set rest loading schemes. Nine male subjects performed an isoinertial Smith machine bench press task (6RM load) with a continuous loading scheme (CONT), an intra-set rest loading scheme equated by total rest time, volume and load (ISRV) and an intra-set rest loading scheme equated by total rest time and load (ISRR). The order of the loading schemes was assigned in a block randomised order with a minimum of 48 hours recovery between each testing session. Attached to the bar of the Smith machine was a linear position transducer that measured vertical displacement with an accuracy of 0.01cm. Displacement data was sampled at 1000Hz and collected by a laptop computer running custom built data acquisition software. Finger prick blood lactate samples were taken from the non-dominant hand using sterile techniques at the following time points: pre-exercise (Pre), immediately post-exercise (P0), five (P5), fifteen (P15) and thirty minutes (P30) post exercise. Blood glucose samples were taken pre-exercise only. It was observed that manipulating the rest period, by increasing the frequency but decreasing the length of each rest period, did not significantly influence the kinematics and kinetics associated with resistance training, but did have an effect on the post-exercise blood lactate response when the load, rest duration and training volume was equated (ISRV). This finding may be of practical significance if fatigue is important in strength development or conversely if power training needs to be performed with minimal fatigue. It was also observed that increasing the frequency of the rest period enabled the subjects to perform a greater number of repetitions (ISRR), resulting in significantly greater kinematics, kinetics and blood lactate accumulation. It may be speculated, therefore, that ISRR training may offer a superior training stimulus for the development of maximal strength and hypertrophy than CONT training methods, as ISRR loading increased the exposure of the muscle to the kinematic, kinetic and metabolic stimuli thought important for the development of these qualities.

This thesis investigated the effect of high intensity, intermittent exercise (HIIE) on fat loss in young, sedentary women. It attempted also to identify possible mechanisms underpinning exercise-induced changes in adiposity. Study 1 investigated some of the metabolic and hormonal responses to two variations of HIIE. Sixteen female subjects were tested. The first session involved a cycle ergometer VO2peak test. The next two sessions were completed in random order. After baseline measures the women did 20 min of HIIE. There was a short bout exercise of 8 s work, followed by 12 s relative rest and a long bout exercise of 24 s work followed by 36 s relative rest. Seven subjects had excess postexercise oxygen consumption (EPOC) and resting metabolic rate determined. Both exercise modalities made significant demands on the participants??? oxygen delivery systems. RER diminished over the 20 min of exercise and plasma glycerol concentrations increased. Lactate concentrations rose. Catecholamine concentrations were elevated postexercise. There was an elevated EPOC associated with above baseline fat utilisation. Study 2, a 15-week training study, was a randomised controlled trial comparing the effects of short bout HIIE and steady state (SS) exercise on fat loss. Forty-five women were randomly assigned to one of three groups: HIIE, SS, or control. Preliminary and posttraining testing included a DEXA scan and a VO2peak test including blood collection. All participants completed 3-d diet diaries and maintained their current diet for the course of the study. Participants exercised three times a week for the next 15 weeks under supervision. The HIIE group did 20 min of HIIE (8 s work:12 s rest) at a workload determined from the VO2peak test. The SS group cycled at 60%VO2peak , building to a maximum of 40 min exercise. Both exercise groups increased VO2peak . The HIIE group had a significant loss of total body mass (TBM) and fat mass (FM) when compared to the other groups. There was no change in dietary intake. There have been a number of studies examining the acute effects of HIIE but, to our knowledge, this is the first study examining the chronic effects of this particular exercise protocol.

The presence of an increased accumulation of intraabdominal fat (IAF) has been linked to dyslipidemia, hyperinsulinemia, and hyperglycemia, which precede the development of type 2 diabetes and coronary artery disease (CAD). It has been shown that IAF begins depostition during childhood. Human studies suggest that regular endurance exercise, that does not necessarily produce an increase in aerobic capacity, can effectively reduce IAF accumulation during these early years. In contrast to human research, studies using animal models of human disease typically employ extremely large volumes of exercise with the intent to maximize aerobic capacity. The present study examined whether half the amount of endurance training, that was previously reported to induce cardiac hypertrophy and approximately double the aerobic capacity of skeletal muscle in rats, would reduce the growth-related accumulation of IAF in growing female rats. Twenty-two 4-week-old female Sprague-Dawley rats were randomly assigned to a running experimental or a non-running control group. The runners exercised on a treadmill 5 days/week for 60 min/day at a speed of 27m/min and up a 15% grade for 10 weeks. After 10 weeks, the parametrial, omental and mesenteric IAF depots and the heart were excised and weighed. Compared with non-runners, the runners had a significantly lower mean parametrial fat mass (2.22 g vs. 3.13 g, p=0.05) and a higher mean heart weight (0.97 g vs. 0.90 g, p=0.05) at the end of 10 weeks. In addition, the lower mean parametrial fat mass in the runners vs. the non-runners (2.19 g vs. 3.19 g, p=0.02) remained significant even after adjusting for the greater heart weights of the runners. One-half the amount of exercise, that was previously reported to induce cardiac hypertrophy and approximately double the aerobic capacity of skeletal muscle in rats, yielded an 8% greater heart weight and a 29% lower parametrial IAF mass, on average, in growing female rats. In addition, the effects of treadmill running on reducing parametrial fat accumulation were independent of the effects of running on increasing heart weight. Thus, future studies examining the effects of exercise on IAF and other health-related metabolic outcomes in rats may consider using lower-dose endurance training protocols that are not designed to maximize improvements in aerobic capacity. / Graduation date: 2002

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 72-74). Also available on the World Wide Web.

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To investigate the effect of a 12-week internet-based PA intervention (Active Living Every Day (ALED)) on average steps/day and time spent in sedentary, light, and moderate/vigorous activity/day, PA was objectively measured at baseline and follow-up using the Omron pedometer and the Actigraph GT3X in 11 bariatric patients (2 male, 9 female; 41±12 years). Significant changes (p<.05) were found in weight, BMI, body fat %, waist and hip circumference, submaximal RPE, percentage of individuals reporting PA and perceived exercise barriers from baseline to follow-up. No significant differences were found in steps/day or daily activity level from baseline to follow-up. Bariatric participants averaged 4454±203 steps/day and 74% of their day was spent sedentary. Based on this data it appears that the 12 week PA intervention was not effective in significantly changing PA behavior in the pre-surgery, but lead to improvements in cardiovascular risk factors, RPE and potential exercise barriers. / School of Physical Education, Sport, and Exercise Science

To demonstrate the dissemination of the Active Living Every Day (ALED) physical activity (PA) intervention program through a healthcare provider recruitment format. A total of 15 subjects were recruited from Delaware Co., IN and attended 6 mandatory visits over a 16-week period. After completion of baseline PA and risk factor profiles, patients were given the 12-week ALED program. PA was monitored using Omron HJ720-ITC pedometers. Reassessment of all PA and risk factor profiles were performed post intervention. No significant changes were observed for mean PA or percentage of time spent performing sedentary activities. Preliminary results suggest a healthcare provider delivery format is not an effective means for the recruitment of sedentary adults. Further subject recruitment is needed to draw conclusions on the effectiveness of the ALED program to increase PA and affect corresponding risk factor profiles. / School of Physical Education, Sport, and Exercise Science

Knowledge of the magnitude of error in any test measure is important in judging the relative significance of that measure. The purpose of this investigation was to determine the day-to-day variability of, and interrelationships between, three anaerobic ergometer tests. The three tests examined were 30 second sprint bouts on a hydraulically-braked Fitron ergometer, 60 second sprint bouts using this same ergometer, and timed rides to exhaustion at a workload corresponding to 125% VO max. A total of twenty-seven subjects were assigned at random to perform four trials of one of these tests at one week intervals. An additional nine subjects performed one trial of each test. The mean coefficients of variation (CVQ SD x 100%) for the performance measures (mean tolerance power or ride time) were 5.4%. 5.47., and 5.37% for the 30 second, 60 second, and exhaustive tests respectively. The mean CV for 10 minute post blood lactate were 11.0%., 13.9%, and 11.0% for these same tests. The mean CV for peak torque and fatiguability were 6.7 and 10.37 for the 30 second test and 5.67% and 7.5% for the 60 second test. Mean power during the 30 second and 60 second tests were significantly related (r=0.69, p<0.05) l but these measures were not correlated with time to exhaustion. Exhaustive time was, however, significantly related to ten minute post exercise lactate concentration (r=0.91, p<0.01). It was concluded that the biological variability of anaerobic tests is similar in magnitude to that reported for measures of aerobic fitness (VO max). These data also indicate that the exhaustive test is a measure of relative, but not absolute, anaerobic tolerance.