The physiological responses to exercise depend on intensity, duration, and type of exercise. The muscles in the body have complex regulation responses in order to create a certain resistance and adaptation to the exercise demands without fatigue. In the following study, we used the model of Alaskan sled dogs in order to analyze changes in gene expression within muscle tissue. Gene expression allows us to look more in depth into temporal or long term biological changes that take place in order for the muscle to adapt and maintain homeostasis. Eight dogs were used for the study; four biopsies from the femoris biceps were taken from each at different time points. Time point 1 (Tp1) untrained dogs, time point 2 (Tp2) after mid training, time point 3 (Tp3) fully trained and time point 4 (Tp4) were taken after dogs had completed a 400 mile run in 4 consecutive days. Time point one was used as a control ratio for the other three time points for analysis one, for the second analysis Tp1 was eliminated as a control. Analysis, one compared Tp2-Tp3 and Tp3-Tp4; the subsequent analysis looked at Tp1-Tp3. For Mid trained animals compared to fully trained, we looked at a total of 25 differentially expressed genes, for fully trained compared against acute exercise performance, we looked at total of 52 differentially expressed genes (based on a ≤0.01 p-value and fold change of ≥3), and untrained was compared to fully trained where we looked at a total of 26 differentially expressed genes. Known transcriptional regulators were mapped from these differentially expressed genes, such as exocyst complex, lysyl oxidase, protein tyrosine phosphatase, protein kinase C, creatine kinase, HSP40, cytochrome P450, ACSL6 gene responsible for Acyl-CoA synthesis, myosin chain, ATP binding, and ubiquitin, among others. These transcripts were linked to important biological pathways, and functional analysis of these pathways demonstrated that changes found in gene expression are responsible for muscle tissue remodeling, energy storage and metabolism changes, cardiovascular enhancement, and activation of elements that regulate metabolism via the nervous system. The following study of transcriptional regulation mechanisms helped identify specific responses to exercise stimuli in the organism that allow the athletes to adapt to the demands of exercise.

Luge is an Olympic sport in which athletes ride feet-first on sleds down an ice-covered track. Competitors spring from the starting position and accelerate their sled by paddling with spiked gloves against the ice surface. Once the Luger leaves the starting section, their downhill motion is solely propelled by the effects of gravity. Athletes compete, one after the other, for the fastest time. Runs can differ by as little as a thousandth of a second, meaning that every minor sled adjustment, change of line choice, and shift of body position is critical. In the past, the sport of Luge has progressed through a series of steps involving trial and error, where changes to the sled and strategy rely more on intuition and race results, rather than in-depth, mathematical analysis. In an effort to try and improve track times for the US Olympic Luge team, a track and driver model is in development in order to simulate a sled going down the track. By doing this, the hope is to be able to pinpoint areas of possible improvement to the sled and see how adjustments can affect the optimum line down the track. A part of this model, which is the focus of the following paper, is the inclusion of an analysis to identify the frictional relationship between the ice surface and the steels of the sled. The model created of the ice-steel interaction was put in the form of a function file, which includes inputs of down force, ice temperature, sled velocity, and steel geometry. Creation of this model and completion of a set of parametric studies allowed for further understanding the interaction between the sled steels and ice surface, specifically applying to the sport of Luge. The model predicts for lower temperatures that at slower sled velocities the coefficient of friction is greater compared to faster sled velocities. This relationship inverts as the ice temperature moves closer to the melting temperature. A sharper steel edge radius was found to be beneficial in lowering the coefficient of friction at lower sled velocities. The sharp edge radius friction benefit decreases as the sled speed increases and is predicted to actually increase friction slightly compared to duller blades at greater velocities. A flat as possible rocker radius lowers friction at all sled velocities, as well as in banked turns where two contact patches are possible. On curves, the pressure on the steel is increased due to the effects of centripetal accelerations. A 1 g versus 5 g normal loading, experienced on the last turns of the track, increases the coefficient of friction on the blade, but also increases the allowable lateral force on the sled before side slip occurs. Understanding the relationships of these parameters, along with the information that may be gained from the driver model, may prove to be useful in choosing optimum sled characteristics and line choice.

This thesis deals with design of snowmobile with hybrid drive. Such a kind of product is supposed to create a new category of snowmobiles in the near future, which is main motivation point. The aim is to design comprehensive product reflecting ergonomical and technological requirements. Center of focus of the project is design that brings new elegant timeless solution.

The purpose of this dissertation was to describe the basic characteristics of performing resisted sprint training using a push sled for the enhancement of sport performance. Specifically, this dissertation served to: 1.) quantify the frictional forces involved between a push sled and an AstroTurf® surface at 6 loads, 2.) derive an estimation of mechanical work performed during sled push training, 3.) outline the velocity characteristics of 3 sled pushing loads scaled to the athletes body mass for comparison against their sprinting ability and 4.) determine the interrelations of fitness characteristics to the ability to sprint under heavy resistance. The following are major findings of this dissertation. 1.) Coefficients of static friction (0.53 – 0.37) and dynamic friction (0.35 – 0.28) were calculated at multiple loads for the AstroTurf® surface. 2.) A direct near perfect relationship exists between total system load of the sled and the forces required to initiate and maintain movement of the sled. Although a direct measurement of force would be more precise and account for changes in velocity, the total system load may be a more practical alternative for daily use. 3.) Statistically significant changes in velocity characteristics were observed within each sled pushing load as well as when comparing each load to sprinting. Decrements in peak velocity ranged from about 40%-51% when comparing resisted to unresisted sprinting. Load increments of 25% body mass were heavy enough to cause statistically significant differences in velocity characteristics. 4.) Statistically significant correlations were observed in anthropometry, sprinting ability, jumping ability, and strength to sled pushing. The results indicate that larger athletes, who can not only produce greater force but produce those forces rapidly, in addition to excelling at jumping and sprinting compared to their peers demonstrate the ability to move faster against heavy loads and slow down less from unresisted conditions. The strongest athletes demonstrated statistically nonsignificant differences in peak velocity drop off when compared to their weaker counterparts; however, small to moderate effect sizes (d = 0.27 – 1.02) were observed indicating a practical difference between strength levels in peak velocity and peak velocity drop off.

Whiplash injuries as a result of rear impact are among the most common injuries in traffic accidents. This is why whiplash injuries have reached a high priority in the research area. In this study, the effects of head restraint position and impact pulse to the whiplash injury have been analyzed by performing whiplash tests using the sled test facility of METU-BILTIR Center Vehicle Safety Unit. Although there are many whiplash test protocols, the test sample has been prepared according to the most recent one, Euro NCAP Whiplash Test Protocol. Three different head restraint positions and three different impact pulses with different severities, totally nine tests have been performed. The tests are performed with a three point generic seat belt and an instrumented Hybrid III 50th percentile male adult crash test dummy is used as the occupant in driver seat of a light commercial vehicle. High speed cameras, sensors on the crash test dummy and a data acquisition system are used to take the test data. This test data has been analyzed and presented according to the defined whiplash assessment criteria and the performance scores of the particular seat for each test have been determined using the whiplash assessment criteria values according to the Euro NCAP Test Protocols.

Sled Crash Test System is one of the key elements in todays high safety vehicle designs. In the crash test systems, high speed imaging by high speed cameras is required. For the success of high speed imaging, high speed cameras should be well secured on the sled of the system which is being accelerated to high-g values to simulate vehicle crash. In this study, structural analysis of the high &ndash / g camera support structure for the sled crash test sytem which is available in METU-BiLTiR Center Vehicle Safety Unit is carried out. For the secure connection of the high speed cameras, three different configurations of the camera support structure with different camera positions are analyzed by transient dynamic analysis. The finite element simulations are carried out under the acceleration of 90 g which is the maximum applicable acceleration on the system. After verification of the configurations with the computer simulations, one of the configuration has been tested at the sled test facility of METU-BILTIR Center Vehicle Safety Unit.

Sprint acceleration training has been highly researched and found that resistance sleds are one of the most effective tools for maximizing training adaptations. The resistance sled is being used by many of the world leaders in athletic training but has yet to be researched for the kinetic and kinematic effects some of its key components cause. The aim of this study was to better understand the effects of the attachment height on the sled and sled rail material on the user's trunk lean and jerking effect caused by the sled. This was done because it was hypothesized that the attachment height has a direct impact on trunk lean and sled rail material has a direct impact on jerk caused by the sled. To test these assumptions, experimental and theoretical data was collected using a single subject study analyzing trunk lean and acceleration values of the sled. The results presented a significant decrease in trunk lean (more horizontal line of action) when the attachment height was raised. Additionally, no significant values were attained to support the assumption that by modifying the sled rail material, jerking effects will decrease. The results indicate that there is a direct correlation between attachment height and trunk lean. More research is needed to better understand the relationship between sled rail material and jerk.

As a new pediatric dummy family, the Q-family, is suggested for the European childsafety regulations (R44) and the updated EuroNCAP, it needed to be tested andcompared to the older pediatric dummy family, Hybrid III, used in testing at Autolivtoday.In this study, tests were performed with the Q6 and the Hybrid III 6-year-old. Bothdummies were subjected to eight sled tests using a EuroNCAP acceleration pulse. The sled represented the interior of a Volvo V70, with integrated booster cushions mounted onto the car body through a rigid fixture. Standard belt were used for all tests, except one where pretensioning was used. Static tests investigated how the chest deflection on Q6 was affected by the shoulder belt geometry. Large difference in belt interaction was observed between the dummies. The beltslipped off the Hybrid III’s shoulder for all tests except one, while the belt on the Qdummy’swas hard to provoke off the shoulder. The overall kinematic behavior, beforethe belt slipped off the Hybrid III’s shoulder, were similar for both dummies. Differences in chest deflection on the Q6, depending on the belt geometry, were observed in both the dynamic and the static tests; a shoulder belt geometry closer to theneck resulted in minor displacement than a mid-shoulder belt geometry. After testing, five different damages were observed on the Q6. / Då en ny familj av barnkrockdockor, Q-familjen, är föreslagen för det europeiskalagkravet som reglerar barnsäkerhet (R44), uppstod ett behov av att testa och jämföradessa mot den äldre familjen av barnkrockdockor som används vid testning på Autoliv idag, Hybrid III. I den här studien utfördes tester på Q6 och Hybrid III 6 år. Båda dockorna utsattes föråtta stycken slädtest i en accelerationspuls enligt EuroNCAP. Släden representerade enVolvo V70 med integrerade barnkuddar som monterats i riggen via en stel fixtur. I alla test utom ett användes standardbälten (i undantagsfallet användes försträckare). Statiska tester gjordes för att undersöka hur Q6 påverkades av olika geometrier på axelbältet. Stora skillnader observerades mellan dockornas bältesinteraktion. Bältet gled av HybridIII:s axel i alla test förutom ett, medan det istället var svårt att provocera av bältet från Q-dockans axel. Innan Hybrid III gled ur bältet var dockornas kinematik liknande. I både statiska och dynamiska tester observerades skillnader i bröstintryckning på Q6, beroende på bältesgeometrin; en geometri där axelbältet var placerat nära nackenresulterade i en mindre intryckning än då axelbältet var placerat mitt på axeln. Efte ravslutad testning upptäcktes fem skador på Q6.