No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

Trunk-mounted monitoring equipment like GPSports SPIHPU units are designed to use global positioning (GPS), accelerometer and heart rate monitoring to evaluate the physical demands of an activity. A medical staff might also consider markers such as running symmetry in evaluation of injury occurrence and rehabilitation. A running symmetry is a ratio of the synchronization of the right and left lower limbs during the gait cycle. An asymmetry due to, a pathology or musculoskeletal injury, results in abnormal loading on the foot that may be detected by trunk-mounted accelerometry. The aim of this study is to evaluate the ability of SPIHPU units to detect running asymmetry. Subjects wore the HPISPU units (100Hz, 16g tri-axial accelerometer, 50Hz magnetometer) while engaged in various running activities. In the first study, artificially inducing a leg length discrepancy led to a difference between running symmetry scores. This discrepancy was confirmed using individual accelerometers attached to the lower leg near the foot. Next, varying running speed did not result in differences in running symmetry. However, the SPIHPU units did detect a running asymmetry between fatigued and non-fatigued conditions. Finally, two case studies showed that the units could identify asymmetry immediately after a lower leg injury and during rehabilitation of anterior cruciate ligament reconstruction surgery. The results of this study show that the HPUSPI units can be reliably used to monitor running symmetry and to detect asymmetrical gait patterns. / Master of Science

No

Precooling, or a reduction in core temperature (Tc) has been demonstrated to be a potent enhancer of endurance running performance, however there is no known mechanism for this improvement. By holding the exercise workload constant, changes in variables such as running economy (RE), heart rate, and ventilation (VE) can be determined as a result of precooling. Improved running economy, or a reduced oxygen cost of a specific workload, is linked to improved exercise performance. Purpose: To determine the changes in flexibility, RE, heart rate, VE, and Tc during running at a constant workload following cool water immersion and to determine any sex-specific responses. Methods: Fourteen well-trained runners (8 males and 6 females) completed four treadmill runs at a sex-specific velocity (8.0 mph for females and 8.6 mph for males). The first two runs served as accommodation trials. The third and fourth runs were preceded by either cool water immersion (24.8oC) for 40 minutes or quiet sitting. Oxygen consumption, heart rate, Tc, VE, and flexibility were measured during both experimental trials. Results: Running economy did not change as a result of the precooling treatment, whereas Tc and heart rate were reduced by 0.4oC and 5 beats per minute, respectively. Minute ventilation was reduced in the female subjects only (1.4 liters/min). Sex differences were apparent in Tc, heart rate, VE, and flexibility response. Conclusion: While the precooling procedure was effective in reducing Tc and heart rate, RE did not change. Thus, improvements in RE cannot explain the dramatic enhancements of endurance running performance that often occur post-cooling. Differences between male and female subjects in response to precooling were identified, most notably in VE.

The purpose of this study was to examine the effects of a 4-week reduction in training volume and intensity on performance of distance runners. Ten well-conditioned males underwent 4-weeks of base training (BT) at their accustomed training distance (71.8 ± 3.6 km/wk) and pace (76% of total distance above 70% V02 max intensity), before reducing training (RT) for an additional 4 weeks. Training volume was decreased by -.66% to 24.8 km/wk and frequency by 50% to 3 runs per week. Training intensity was reduced such that all running was at less than 70% V02 max (68.2 ± 1.6%). At the end of BT (week 0), and weeks 2 and 4 of RT, resting heart rate, calculated plasma volume, testosterone and cortisol levels, and submaximal treadmill efficiency were assessed. At weeks 0 and 4, V02 max and 5 kilometer race performance was determined. The ratio of testosterone to cortisol was increased significantly with RT (0.054 ± 0.008 at week 0 to 0.082 ± 0.020 at week 4), although the individual testosterone and cortisol concentrations were not significantly altered. Maximum oxygen consumption, and time to exhaustion during the max tests were not altered with RT. Body weight tended to increase (p=0.09) due to a significant increase in percent body fat (p<0.05). Submaximal treadmill runs at 65%, 85%, and 95% V02 max revealed no alterations in absolute V02 while relative V02 decreased significantly. This decrease in relative V02 was due partially to the weight increases and partially to a significant increase in respiratory exchange ratio (RER). Resting and submaximal treadmill heart rate (HR) were unchanged with FIT, while maximal treadmill HR and race HR were increased significantly. Calculated plasma volume was unaltered. Leg and overall ratings of perceived exertion were decreased during RT with the overall rating reaching significance (p<0.05). Blood lactic acid concentration was found to be significantly higher at the 95% V02 max workload following RT (8.39 ± 0.46 vs 9.89 ± 0.46 mmol/L at week 0 and 4, respectively). Five kilometer race time increased significantly from 16.6 ± 0.3 at week 0 to 16.8 ± 0.3 minutes at week 4 (12.1 seconds). It is concluded that a 4-week reduction in training volume and intensity in these runners resulted in a significant decrease in race performance despite the maintenance of aerobic capacity. / School of Physical Education