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Peters, Fredrick JudeThe Effects of Localized Vibration on Delayed Onset Muscle Soreness Following Intense Eccentric Cycling
PHD, Kent State University, 2016, College and Graduate School of Education, Health and Human Services / School of Health Sciences
Delayed onset muscle soreness (DOMS) is musculoskeletal pain resulting from physical activity. DOMS affects athletic performance, therefore therapy is of interest to athletes. The purpose of this study was to examine the effects of localized vibration (biomechanical muscle stimulation, BMS) on biomarkers of DOMS following eccentric cycling, and to test changes in muscle length and soreness. We investigated if BMS reduces DOMS and enhances muscle function following eccentric exercise and if creatine kinase (CK), lactate, and pain were affected. Twenty-eight recreationally active men (18 – 40 years old) were randomized into control or BMS groups. Subjects performed 5 minutes of eccentric cycling, then either received BMS, or rested. Outcome variables, plasma creatine kinase, blood lactate, pain scores (Likert), muscle length, muscle pain (self-reported), and pressure algometry were collected at four intervals (baseline, pre-cycling, 24 hours post-cycling, and 48 hours post). A main effect of time was found for quadriceps pain threshold (F(3, 78) = 3.02, p = 0.04). A main effect of time was found regarding an increase in lactate (p = .016; T0 to T1) and decrease in lactate (p = .025; T1 to T3). A main effect of time for Likert pain score was found pre-cycling versus post-cycling (p = .0001). There were no significant interactions between group (BMS or control) and time. This study does not support our hypotheses regarding localized vibration and recovery from DOMS. However, we found significance regarding a main effect of time for pain threshold in the quadriceps, Likert pain score, and lactate level.

Committee:

Angela Ridgel (Advisor)

Subjects:

Health Sciences; Kinesiology

Keywords:

eccentric cycling; delayed onset muscle soreness; DOMS;

Fischer, Stephen MichaelMETABOLIC DIFFERENCES BETWEEN A BOUT OF ECCENTRIC, CONCENTRIC, AND TRADITIONAL RESISTANCE EXERCISE
MS, Kent State University, 2016, College and Graduate School of Education, Health and Human Services / School of Health Sciences
PURPOSE: To determine the extent to which metabolic variables such as VO2(ml/kg/min), percentage of energy derived from carbohydrates (%CHO) and heart rate (HR) as well as blood glucose and lactate vary between resistance workouts comprised of solely eccentric, concentric or traditional muscle contractions. METHODS: N=12 men and women completed a traditional (TRAD), concentric (CONC), and eccentric (ECC) full-body resistance workout at 65% of a measured 1 repetition max with each condition matched for work. During each condition, the subject was fitted to a metabolic cart and metabolic variables were recorded through indirect calorimetry and heart rate monitor. Blood glucose and blood lactate were taken at five different stages. RESULTS: Both the TRAD and CONC conditions resulted in significantly (p < 0.001, and p < 0.001 respectively) greater VO2 values when compared to the ECC condition. Accumulation of lactate Post Ex. was also significantly (both p < 0.001) greater in the TRAD and CONC compared to the ECC. CONCLUSION: Results indicate a much greater metabolic demand from concentric and traditional contractions compared to eccentric muscle contractions on a whole body level.

Committee:

John McDaniel, Ph.D. (Advisor)

Subjects:

Kinesiology

Keywords:

Eccentric Concentric Metabolism

Stacy, Mitchel R.The Effect of Eccentric Exercise-Induced Muscle Injury on Vascular Function and Muscle Blood Flow
Doctor of Philosophy, University of Toledo, 2011, Exercise Science

The purpose of this dissertation was to examine the effect of eccentric exercise-induced muscle injury on local vascular function and muscle blood flow in humans. Healthy, male subjects performed maximal eccentric contractions to induce muscle injury to the forearm flexor muscles, with subsequent changes in maximal isometric strength and vascular responses assessed at one, 24, 48, and 96 hours post-injury. Endothelial-dependent and-independent vasodilation was measured using brachial artery flow-mediated dilation (FMD) and sublingual nitroglycerin administration, respectively. Mean blood velocities were measured by Doppler ultrasound and later used for the calculation of blood flow and the shear stress area under the curve (SSAUC). Subjects performed sub-maximal handgrip exercise 48 hours following injury and muscle blood flow was assessed via Doppler ultrasound.

Eccentric exercise resulted in significant decreases in maximal isometric strength for up to 96 hours. Endothelial-dependent and –independent vasodilation was also significantly impaired for up to 96 hours following eccentric-induced injury. The shear stress stimulus (SSAUC) responsible for the FMD response was significantly reduced from one to 48 hours post-injury. However, resting blood pressure and blood flow remained the same throughout the duration of the study despite an increase in brachial artery diameter at one and 48 hours following eccentric exercise. Additionally, the muscle blood flow response to dynamic sub-maximal handgrip exercise was not significantly different 48 hours post-injury.

In summary, these results suggest that skeletal muscle injury results in prolonged impairment of local vascular function without influencing subsequent muscle blood flow at rest or during sub-maximal exercise.

Committee:

Barry Scheuermann, PhD (Committee Chair); Suzanne Wambold, PhD (Committee Member); David Weldy, MD, PhD (Committee Member); John Thistlethwaite, PhD (Committee Member)

Subjects:

Biology; Physiology

Keywords:

eccentric exercise; muscle injury; endothelial function; vascular function; blood flow

PILLUTLA, JAYANTHILAMINAR NON-NEWTONIAN FLOWS IN ECCENTRIC ANNULI WITH INNER CYLINDER ROTATION
MS, University of Cincinnati, 2001, Engineering : Mechanical Engineering
The hydrodynamic characteristics of fully developed axial laminar flow of non-Newtonian fluids in eccentric annuli with a rotating inner cylinder are investigated. The non-Newtonian, shear-thinning fluid is modeled by the Power-law or Ostwald-de Waele constitutive relationship. Using finite-difference method to solve the governing flow equations in bipolar coordinates, computational results for a wide range of annulus geometry (0.2 ≤ r* ≤ 0.8, 0 ≤ eccentricity ≤ 0.8), rotational Reynolds number (0 ≤ Re r ≤ 150) and flow behavior index(0.4 ≤ n ≤ 1) are presented. The rotational speeds considered in this study are restricted to the sub-critical Taylor number regime. The results delineate the effects of annuli r* and eccentricity, and inner cylinder rotation speed on the flow structure and frictional losses. Velocity distributions in the flow cross-section and the variation in friction factors (f Re) for fully developed flows in different eccentric annuli flow index are presented. Here, the non-linear shear behavior of the fluid is found to further aggravate the flow maldistribution, and once again the eccentricity is seen to exhibit a very strong influence on the friction behavior. These results are of significant importance to the design and operation of oil and gas drilling wells.

Committee:

Dr. Raj M. Manglik (Advisor)

Subjects:

Engineering, Mechanical

Keywords:

eccentric ducts; Non-Newtonian flows; power law

Habouh, Mohamed IKey Way Joint Strength of Precast Box-Beam Bridges
Doctor of Philosophy, University of Akron, 2015, Civil Engineering
Satisfactory performance of non-composite adjacent box-beam bridges depends on the effectiveness of the key way, waterproofing membrane and tie rods, and the related construction practices. Development of cracks at the longitudinal joints of such bridges is often a recurring problem that causes water leakage at the joints and corrosion of the embedded prestressing strands. The primary objective of this study was to identify the sources, causes and effects of inadequate joint performance in adjacent box-beam bridges, and to develop prevention measures. The structural performance of key way joints with the existing and new grout materials were evaluated and correlated with field measurements under traffic loading. Observation of construction practices and an investigation of a bridge that was in service for 32 years at the time of its demolition were also included. This study revealed that shear transfer strength of key way joints under symmetric loading can be increased compared to the joints that use the current ODOT-approved grouts and key way details through proper selection of grout material, adjustment to the key way geometry, and joint surface preparation. In beam configurations, this increase can be by a factor of up to 7.3 prior to the occurrence of first crack. Key way joints with a combination of the currently specified ODOT geometry and ODOT-approved grouts are incapable of carrying any shear loads in conjunction with out-of-plane moments. However, with suitable modifications, it is possible to increase the shear strength of these joints under eccentric loading. From the limited site inspections done in this project, the practices followed at construction sites seem to be seriously flawed and may be largely contributing to water leakage problems in box-beam bridges. New key way geometries and the grouts that were developed and tested in this project are suitable for implementation.

Committee:

Anil Patnaik, Prof. (Advisor)

Subjects:

Engineering

Keywords:

box beam bridges, key way strength, key way geometry, joint strength, modeling of eccentric loading, out of plane moment, grout evaluation, polymer grout

Mustafa, MansoorInvestigation into Offset Streams for Jet Noise Reduction
Master of Science, The Ohio State University, 2015, Aero/Astro Engineering
This effort investigates the near field behavior of two ideally-expanded subsonic dual-stream jets. One case implements a traditional symmetric, concentric dual-stream nozzle configuration while the other imposes an asymmetric, eccentric layout to model the behavior of an offset stream. The essence of an offset stream is to force an uneven azimuthal distribution of the secondary coflow and create an outside stream that varies in thickness. Past studies have shown a benefit in acoustic propagation in the direction of the thickest coflow and the present work further analyzes this phenomenon. A LES (Large Eddy Simulation) approach is implemented to run the simulations for both cases and a number of qualitative and quantitative analyses tools are used for post-processing. A reduction in the noise levels for the lower, thicker side of the eccentric nozzle is observed in comparison to the baseline concentric case. Examination of the mean flow behavior shows a shorter, thinner primary potential core for the offset case and a faster axial velocity decay rate. The asymmetric distribution of the coflow causes varying velocity profiles in the radial direction for the top and bottom regions and consequently produces unique flow features on either side. Lower levels of shear stress and slower decay rates lead to less turbulence production on the lower side of the eccentric nozzle. An investigation into the flow structures reveals lower vorticity and weaker convective structures on the bottom which influences propagation in that direction. Two-point correlation analysis reveals the presence of smaller turbulence scales in the lower, thicker portion of the eccentric case. This is further confirmed by an Empirical Mode Decomposition (EMD) study that shows lower frequency ranges dominate the concentric near field in comparison to the eccentric. The combination of these unique features demonstrate the principles behind the acoustic benefit of implementing offset stream flows in dual-stream nozzle configurations.

Committee:

Datta Gaitonde (Advisor); Mei Zhuang (Committee Member)

Subjects:

Aerospace Engineering

Keywords:

offset; noise reduction; jets; aerospace; aerodynamics; LES; computational simulation; jet noise; eccentric; concentric; dual-stream; nozzle

Fares, Ali F.Volume measurements of human upper-arm muscles using compounded ultrasound imaging system
Master of Science (MS), Ohio University, 1995, Electrical Engineering & Computer Science (Engineering and Technology)

Electrical Engineering and Computer Science

Committee:

Jeffrey Giesey (Advisor)

Keywords:

Medical Scanning Modalities; Ultrasound; Eccentric-Exercise Muscle Induced-Injury