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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Relationships Between Running Biomechanics and Femoral Articular Cartilage Thickness and Composition in Anterior Cruciate Ligament Reconstruction Patients

Lee, Hyunwook 07 July 2023 (has links) (PDF)
Background: Patients with anterior cruciate ligament reconstruction (ACLR) have demonstrated morphological and compositional changes in femoral articular cartilage. However, it is unclear how running biomechanics are associated with femoral cartilage thickness and composition for both ACLR patients and controls. Objectives: (1) to compare measures of femoral cartilage thickness and composition between ACLR patients and matched non-ACLR controls at resting, (2) to investigate how 30 minutes of running influences the aforementioned measures for ACLR patients and controls, and (3) to investigate relationships between running biomechanics and knee cartilage thickness and composition in ACLR patients and controls. Methods: Twenty ACLR patients (age: 23 ± 3 years; mass: 69.7 ± 9.9 kg; time post ACLR: 14.6 ± 6.1 months) and 20 matched non-ACLR controls (age: 22 ± 2 years; mass: 67.1 ± 10.9 kg) participated in the study. A running session required both groups to run for 30 minutes at a self-selected speed. Before and after running we measured femoral cartilage thickness via ultrasound imaging. An MRI session consisted of T2 mapping. Independent t-tests were used to examine differences in femoral cartilage thickness and T2 relaxation time at resting, and thickness changes following the run between the two groups. Pearson correlations were used to explore relationships between running biomechanics and femoral cartilage thickness and relaxation time at resting. Results: The ACLR group showed longer T2 relaxation times in three regions of the medial femoral condyle at resting compared with the control group (overall: 54.9 ± 14.2 vs. 39.3 ± 8.2 ms, P = 0.001; central: 51.2 ± 16.6 vs. 34.9 ± 13.2 ms, P = 0.006; posterior: 50.2 ± 10.1 vs. 39.8 ± 7.4 ms, P = 0.006). Following the run, the ACLR group showed greater deformation in the medial femoral cartilage than the control group (0.03 ± 0.01 vs. 0.01 ± 0.01 cm, P = 0.001). Additionally, the ACLR group showed significant negative correlations between resting T2 relaxation time in the central region of the medial femoral condyle and peak vGRF, and vertical impulse (r = -0.53, P = 0.013; r = -0.46, P = 0.041, respectively) during running. Conclusions: The ACLR group showed greater water content in medial femoral cartilage and greater deformation in medial femoral cartilage thickness following 30 minutes of running compared with the controls. In addition, the ACLR group demonstrated significant negative correlations between water content in medial femoral cartilage and vGRF. Our findings suggest that those who are at least 24 months post-ACLR have degraded cartilage composition and their cartilage is more sensitive to joint loading morphologically.
402

The determinants of running performance in middle distance female athletes

Mpholwane, Matome Lieghtone 19 August 2008 (has links)
ABSTRACT Male subjects are invariably used to study the physiological determinants of middle distance running performance. Studies that do include females have examined only the aerobic contribution to middle distance running performance. The aim of the present study was to investigate aerobic, anaerobic and muscle function factors that could be used to predict middle distance running performance in female runners. This study was performed at an altitude of 1800m. Eleven middle distance female runners aged 18-20 were selected for the study. Aerobic capacity was assessed by measuring the maximal oxygen consumption (VO2max), running velocity at maximal oxygen consumption (vVO2max), running economy (RE) and onset of blood lactate accumulation (OBLA). The blood lactate curve of each subject was constructed by relating the oxygen consumption, to the plasma lactate concentrations. Anaerobic capacity was determined by measuring the maximum accumulated oxygen deficit (MAOD) on a treadmill. Muscle function was assessed by having the subjects cycle as fast as possible against changing brake weights ranging from heavy to light using a Monark cycle ergometer. The brake force (kg) was related to velocity (rpm).
403

Effect of meal with different glycemic index and glycemic load on immune responses and running performance. / CUHK electronic theses & dissertations collection

January 2006 (has links)
In conclusion, the studies reported in this thesis suggested that the CHO amount, whether provided by a pre-exercise CHO meal or short-time, i.e., 3-day, CHO loading, plays a pivotal role in regulating the immune responses before, during, and after endurance exercise. Although GI and GL independently affect the exercise performance and immune responses, the amount of CHO consumed remains a determining factor. The potential benefits on immune system and endurance performance after the low GI and low GL diet (L-L) should be noted and warrant further investigation. Although the HGI and LGI meals demonstrated similar effects on endurance performance when large amount of CHO-electrolyte solution consumed during the exercise, pre-exercise LGI meal can hasten the IL-6 responses during the recovery. (Abstract shortened by UMI.) / The aim of this thesis was to investigate the influence of pre-exercise carbohydrate (CHO) meal(s) with different glycemic index (GI) and glycemic load (GL) on endurance running performance, physiological, and immune responses. / The first study (Chapter 4) examined the influence of a pre-exercise meal with different GI and GL on subsequent endurance running performance, physiological, and immune responses. Eight endurance-trained male runners completed three trials in a randomized order, separated by at least seven days. These responses were characterized by a lower CHO oxidation with a concomitant higher glycerol and FFA in the H-L trial. Consumption of a pre-exercise high CHO meal, i.e., H-H and L-L, resulted in less perturbation of circulating numbers of leukocytes, neutrophils, and T lymphocyte subsets, decreased elevation of plasma IL-6 concentrations immediately after exercise and during the 2 h recovery period when compared to the H-L trial. These responses were accompanied by an attenuated increase in plasma IL-10 concentrations and plasma cortisol concentrations at the end of 2 h recovery. It was concluded that the amount of CHO consumed 2 h before endurance exercise appears to be the main influencing factor on immune responses irrespective of its GI and GL value. / The second study (Chapter 5) examined the influence of a 3-day CHO loading with different GI and GL meals on the supercompensation status, running performance, physiological and immune responses. Nine endurance-trained male runners were recruited in this study. The procedures basically involved a 3-day CHO loading with different GI and GL meal [CHO intake (% of energy intake), GI, and GL per day are 73%, 80, and 553 for the high-GI and high-GL (H-H); 73%, 42, and 249 for the low-GI and low-GL (L-L); 31%, 78.5, and 227 for the high-GI and low-GL (H-L) respectively] after a glycogen-lowering exercise. Two hours after the breakfast on day 4, participants performed the running protocol as described in the first study. There was no difference in time to complete the 10-km TT between the two trials with high-CHO loading, i.e., H-H and L-L (51.3 +/- 5.3 min vs 48.6 +/- 1.3 min, NS). These results suggested that 3-day CHO loading with low GI and low GL (L-L) is more effective in improving endurance performance when compared to a high GI but low GL diet (H-L). It appears that the amount of CHO consumed during the 3-day CHO loading remains the key influencing factor on immune responses despite of the differences in the GI and GL value. / The third study (Chapter 6) investigated the influence of pre-exercise meal with different GI on subsequent endurance running performance and immune responses when CHO-electrolyte solution was consumed during exercise. Pre-exercise LGI meal attenuated the increases of cortisol when compared with CON and hastened the recovery of the IL-6 value to baseline when compared to that in HGI and CON trials during the first hour of the recovery. The results suggested that beside of CHO quantity (CHO content), the role of CHO quality (GI) in the diet consumed 2 h before exercise should be considered when investigating the influence of CHO supplementation on the exercise-induced transitory immunosuppressive effects. / Chen Yajun. / "August 2006." / Adviser: Stephen Wong Heung-Sang. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1597. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 199-225). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
404

Investigating the suitability of laser sintered elastomers for running footwear applications

Davidson, Craig January 2012 (has links)
The research contained within this thesis formed part of an Engineering and Physical Sciences Research Council (EPSRC) funded project based at Loughborough University, which aimed to investigate the use of additive manufacturing (AM), and in particular sintering technologies, for the production of running footwear sole units. Laser sintering (LS) is an AM process which produces parts directly from a computer aided design (CAD) file by selectively fusing successive layers of powdered material using a CO2 laser. LS imparts significant advantages over traditional manufacturing techniques including extensive design freedom, the ability to manipulate the local properties of a single material part as well as economical manufacture of bespoke items due to the elimination of tooling. Modifying the mechanical properties and/or geometry of sole units has been shown to provide benefits in the areas of performance, injury risk reduction and comfort, especially when considering elite athletes on a subject specific basis. Given the attributes of LS outlined above, the technology offers significant potential to produce sole units offering high added-value compared to conventional counterparts which are limited by the constraints of traditional processing techniques such as injection moulding. However, the mechanical capacity of LS polymers in context of such application was unknown. Accordingly, this research investigated the suitability of a laser sintered elastomer (LSE) material, in view of key selected mechanical properties, for the manufacture of running shoe midsoles. The midsole is the primary functional component in the sole unit of a running shoe used for distance running on hard surfaces. Following a preliminary assessment of the selected LSE (TPE 210-S), a new dynamic test method was designed to assess the compressive, fatigue and time dependent recovery properties of midsole material specimens under loading conditions representative of in-service use. The method was successfully implemented on an electro-mechanical test apparatus (previously unreported upon in literature) and used firstly, to benchmark the aforementioned properties of a range of ethylene vinyl acetate (EVA) and polyurethane (PU) midsole foams representative of the range currently used in production, and secondly, to establish the same property set for TPE 210-S specimens produced across a range of laser powers (LP's). Initial cycle operating ranges in terms of key compressive properties were established for EVA and PU materials. All conventional variants showed considerable deterioration from these initial values over the 125,000 cycle test regime, but subsequently demonstrated partial recovery when left unloaded post-test. PU grades generally exhibited better fatigue performance and findings were consistent with those of previous studies. Whilst variation in LP facilitated linear variation in displacement and stiffness properties for TPE 210-S, all specimens yielded a stiffer and more elastic response than that of conventional foams at the outset; initial compressive operating ranges, whilst within close proximity, did not overlap. However, fatigue performance was found to be superior with only relatively small property changes occurring over the test regime regardless of LP. Furthermore, no signs of catastrophic specimen failure (e.g. cracking) were visually apparent. In this respect the material showed good suitability for midsole applications, but further work is required to address increasing the available compressive property range which fell outside the scope of this work.
405

The Role of Running in Female Separation-Individuation

Horne, Amy Beth 12 1900 (has links)
The present research investigated the relationship between separation-individuation issues and the motoric activity of running in adult female development. Literature on sex roles and sociocultural factors was presented. Previous research on physical activity and mental health was reviewed. Psychodynamic formulations provided the framework for exploring and understanding a woman's involvement in running. Measuring instruments tapped concepts related to independence and separateness.
406

Psychobiological and Pacing Characteristics of Field Tested Endurance Performance

LaCroix, James Scott 05 1900 (has links)
This study investigated the psychobiological and pacing characteristics of the 1.5 mile run. Sixty-six males (18-27 years) performed the run, and were monitored for ratings of perceived exertion, heart rate and split times. The perceived exertion values increased in a near-linear fashion inconsistent with other measures, and thus are not considered a supportable indicator of physiological performance during the run. Pace was characterized by an initial sprint that slowed to a near-steady pace and concluded with a final sprint. The initial and final sprints were most highly related to the variance of performance time. Initially, heart rate accelerated greatly. This acceleration slowed, ending in near-maximum heart rates. The data suggested that performance may rely heavily upon anaerobic mechanisms, and that variance in previously reported correlational analyses of VO2max and 1.5 mile run performance times may be somewhat due to anaerobic mechanisms.
407

Vliv použité běžecké obuvi na kinematiku dolních končetin a pánve v průběhu oporové fáze běhu / The influence of running shoes on leg and pelvis kinematics during the stance phase of run

Novák, Čestmír January 2014 (has links)
Title: The influence of running shoes on leg and pelvis kinematics during the stance phase of run Objectives: The main objective of this thesis is to detect whether there exists a connection between the type of shoes used and changes in pelvis and legs kinematics in sagittal plane while running. Methology: For a purpose of the thesis research 12 active sportsmen (6 men and 6 women) participated in lab tests. Each of them was running on a tread mill for three time sequences - each counting 20 seconds - with changes in conditions applied as follows: barefoot run, minimalistic shod run, classic shod run. The 3D analysis was analysed using the Qualisys system (200 Hz). Data analytics was executed using the Qualisys Track Manager programme, where a comparative method was applied. Further statistical procedures ANOVA a Tukey test were performed in a programme called OriginPro 8. Key findings: The executed lab tests proved influence of running shoes on legs and pelvis kinematics during a stance phase of run. The main changes in kinematics were found in an ancle during touchdown, where the angle significantly increased while running barefoot rather than classic shod running. An analysis of pelvis kinematics parameters has proven that there are no changes in pelvis movements while running in different types...
408

Analysis of Changes in Running Technique Between a Shod and Barefoot Running Condition.

Andersson, Matilda January 2016 (has links)
Background: Lately, barefoot running has become popular and there is a debate on the pros and cons of barefoot running with regards to running injuries. Many factors are causing injuries and one of the factors discussed is the fact that we run in shoes. When we run in shoes the biomechanics of the running technique may and therefore be a possible cause to injury. Aim: The aim of the study was to assess how the foot strike pattern, angle of the knee and ankle joint at time of initial contact, as well as the step length changes between a shod and barefoot running condition in habitually shod runners when running in a pace equivalent to their running pace over ten kilometers. Method: Twenty-seven healthy runners (18 male, 9 female) were included in the study. The study took place at the fitness center of Halmstad University. Subjects ran on a treadmill, in an individual pace equivalent to their running pace over ten km, both in a shod and barefoot running condition. Two-dimensional analysis of the sagittal plane kinematics of the knee joint, ankle joint and foot position to horizontal, foot strike pattern and step length was done. Participants ran for ten minutes with shoes and for five minutes barefoot. Running technique was videotaped using an Iphone 6 camera and landmarks were marked with white tape to ease the analysis. Results: Changes in foot strike pattern was observed. When running barefoot 63% of the subjects adopted a non-heel strike pattern compared to 18.5% when shod (p=0.001). Knee flexion was increased at IC for the barefoot condition, with 164°±6 relative knee angle compared to 167°±6 when shod (p=0.001). Ankle angle at IC did not show a statistical significant difference between conditions (p=0.657). When barefoot the angle was 117°±8 compared to 115°±8 when shod. Foot angle to horizontal showed a flatter foot placement at IC with a less dorsiflexed foot for the barefoot condition (-4°±8) compared to shod (-12°±8), (p=0.001). Step length was decreased for the barefoot condition (0.82m ±0.15)   compared to shod (0.85m ±0.13), (p=0.008). Conclusion: Results are consistent with previous findings that barefoot running in some cases change the running technique with a flatter foot placement, an increased knee flexion at IC and a decreased step length. However, caution must be taken when habitually shod runners transition to barefoot running in regards to the biomechanical changes that may occur. To benefit from barefoot running a non-heel strike pattern is required. Further, the running technique may be the more important factor, regardless of wearing shoes or not.
409

The effect of "fusafungine" on the incidence of upper respiratory tract symptoms in ultradistance runners / The effect of "fusafungine" on the incidence of upper respiratory tract symptoms in ultradistance runners

Kiessig, Michael, Kiessig, Michael 22 August 2017 (has links)
Fusafungine is an antibiotic of fungal origin with a potent local anti-inflammatory action (German-Fattal, 1995; German-Fattal, 1996). It is administered locally to the nasal and pharyngeal mucosa by spray. It can be hypothesised that the anti-inflammatory action of fusafungine may decrease the development of mucosa! inflammation in such a manner that the incidence of symptoms of upper respiratory tract infection may be reduced if it is administered before, during and after completion of an ultramarathon. Furthermore, fusafungine could also reduce the risk of secondary bacterial infection. The potential value of fusafungine in reducing the symptoms of upper respiratory tract infections or the development of bacterial upper respiratory infection is the focus of this thesis.
410

Stability Analysis Of Leg Configurations For Bipedal Running

Jaiswal, Nitin 06 September 2019 (has links)
No description available.

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