No description available.

Abstract Background: The squat is one of the most used exercises in the field of strength and conditioning. It is included as a core exercise in many sports training programmes to enhance athletic performance due to its biomechanical and neuromuscular similarities of a wide range of athletic movements. The barbell squat commonly used by athletes participating in resistance training and it is generally performed using regular athletic shoes or specially designed weightlifting shoes. However it is now getting more common to perform the barbell back squat in barefoot or in barefoot-inspired foot wear. Weightlifting shoes may be well known to weightlifters but to the noncompetitive lifters and professional athletes they are in general unfamiliar. It is believed that the structure of the weightlifting shoe supports proper squat mechanism. There is however limited scientific data reporting on the use of weightlifting shoes and therefore, it may be needed to investigate how weightlifting shoes affects the lower body lifting kinematics in the back squat compared to other conditions. Aim: The aim of the study was to compare the kinematic differences that appears in the sagittal plane when performing a barbell back squat wearing weightlifting shoes and barefoot. Method: Fifteen healthy participants (n=15) completed the study. The study included the barbell back squat in three sets of three repetitions on 50, 60 and 70% of the participant’s 1RM. The participants performed the movement in both weightlifting shoes and barefoot in an order randomly chosen and all movements was recorded with a digital camera from the sagittal plane. Results: The results showed that the angles were greater in the weightlifting shoe condition on all percentage. The results showed that there was no statistical significance in the hip angle at 50% of 1RM (p= 0,370) or at 70% (p = 0,053) but a statistical significance in the hip angle at 60 % (p = 0,028). The results showed no statistical significance in the ankle angle at 50% of 1RM (p = 0,997), 60% (p = 0,182) or 70 % (p = 0,332). Conclusion: Findings from this study did not demonstrate that there was a significant difference between performing a barbell back squat in weightlifting shoes and barefoot. More research is needed to investigate and compare more variables in the difference between performing a barbell back squat wearing weightlifting shoes and barefoot.

published_or_final_version / Orthopaedics and Traumatology / Master / Master of Philosophy

Bakgrund: Många studier kan påvisa behovet av kommunikation och information mellan vårdare och patient oavsett profession.Tidsbrist och allt mer slimmade organisationer,med en ökande åldrande befolkning ställer ökade krav på förmåga och kunskap om kommunikation. Andra försvårande omständigheter är språkliga barriärer med en befolkning där alla inte har svenska som sitt modersmål. Teach –back är en metod som säger sig underlätta och stödja en kommunikation för att säkerställa informationen mellan patienter och vårdare. Den syftar också till att öka förutsättningarna för egenvård. Eftersom det är ett viktigt område inom omvårdnad syftar litteraturstudienatt ta reda på vad som finns beskrivet avseende Teach –back. Syfte: Att beskriva användningsområden för metoden Teach –back. Metod: Litteraturstudie baserad på åtta vetenskapliga artiklar. Resultat: Resultatet presenteras i följande teman. Det första temat är hälsolitteracitet och förstå given information och det andra är att säkerställa processen mellan vårdgivare och hemmet. Det tredje temat är att sjuksköterskans insikt om patienters kunskap om den egna hälsan. Analysen visar att inga slutsatser kan dras att Teach-back främjar omvårdnad. Däremot finns det resultat som bekräftar att Teach-back skapar förutsättningar för patient medverkan Diskussion: De delvis motstridiga uppgifterna och att de kan vara olika faktorers som styr resultatet gör att det är svårt att påvisa att Teach-back är lösningen för en kvalitetssäkrad kommunikation. / Background: Academic studies tend to demonstrate the need of communication and exchange of information between the health care provider and the patient, this regardless of the profession and socioeconomic background of the caretaker. Lack of time as well as the increased pressure of trimming the economic costs combined with an aging population creates a higher demand on the skills and knowledge of communication. Moreover our modern sociality is presenting some language barriers because of a growing part of the population whom does not have Swedish as their mother tongue. Teach -back is a method that claims to support a method of communication to ensure the quality of information between patients and care givers. Teach-back as a method also aims to enhance the ability of self-care for the patient. Self-care is regarded as an important area of ​​nursing, therefore the review of the literature in this study intends to map out all of the academic literature there is about the method Teach –back. Aim:To describe the uses for the method Teach-back. Method: A literature study based on eight scientific articles. Results: The result is presented in three following themes. The first theme are healthliteracy and understanding given information and the other is to ensure the process between the healthcare provider and the caretaker. The third theme are nurse’s understanding of the patient’s knowledge about their own health status. The analysis shows that no conclusions can be drawn regarding whether the teach-back method furthers the care or not. However, there are results confirming the fact that Teach-back creates a good environment for patient involvement. Discussion: The partly conflicting results that have emerge from the literature which shows that there may be different factors that have an effect on the outcome, making it difficult to conclude that the Teach-back method is the solution for assuring the quality of the communication.

This work is the first 3-D continuum study of the free vibration of skewed and simultaneously skewed and twisted, cantilever parallelepipeds. The purpose of this study is to make available in the literature an enlarged data base of natural frequencies of these practical problems for researchers and design engineers to draw upon. The Ritz method is used to determine approximate natural frequency data. The total potential energy of the parallelepipeds is formulated using the three-dimensional theory of elasticity. The three orthogonal displacement components (u,v,w) are each approximated by finite triple series of simple algebraic polynomials with arbitrary coefficients (which are determined by applying the Ritz method). All terms of the series are constructed to satisfy the geometric boundary conditions at the fixed end of the parallelepiped. No other kinematic constraints are imposed in this analysis. Hence, the finite series of algebraic polynomials are both admissible and "mathematically complete" (75). Several convergence studies of natural frequencies are conducted on cantilever parallelepipeds. Effects of geometrical parameters such as side ratio, thickness ratio, skew angle, and twisted angle are presented in the form of nondimensional tables and graphs. Accuracy of solution method is substantiated through comparison with existing rectangular, skewed, and twisted plate results. The central focus of these comparisons are to verify the correctness and accuracy of free vibration data obtained by investigators using classical plate theories and two- and three-dimensional finite element methods.

No description available.

No description available.

Standing at a workbench is required for manual work including sorting and assembly. When work heights and reach distances are not matched to stature or arm length, the trunk assumes a partially bent position, which increases the postural effort required to stand or to reach to far distances. As a result, the biomechanical load on the lumbar spine is raised, which contributes to a higher risk for back pain. In ergonomics, assistive devices are being developed to counter this effect. A new leaning device was tested in the laboratory with forward-bent standing and reaching where the trunk was bent forward and twisted to reach to a far target 45° from the center. This device supported the trunk at the upper chest. With leaning, back muscle activity decreased by ~ 60% with forward-bent standing and ~ 23-30% with the off-center reach, depending on reach height. Because leaning changed how standing remained balanced, ~12° less bending was required to reach the target. Therefore, upper-trunk support may be helpful for benchworkers when ergonomic design is not possible; some product development and testing is still needed to provide the right amount of support at the right time and to ensure there is no rib joint irritation. An interesting outcome from these previous studies was related to workers’ posture when they leaned against a workbench that was adjusted for heavier work (hip height). Low back muscle activity was unchanged with forward-bent standing, but decreased by ~ 23-30% with the off-center reach. This reduction was accompanied by greater twist at the mid back as a way of compensating for a loss of hip rotation. Three different heights for bench leaning were compared in a third study: elbow height, hip height and below hip height. The results showed that leaning at elbow height lowered the work demand by ~16-24% for far reach, partially due to changed motions consistent with greater mid back movement and coincided with ~ 8% increase in work demands at the mid-back and greater scapular recruitment. Therefore, more research is needed to establish work height guidelines for use when leaning against a workbench. / Thesis (Ph.D, Kinesiology & Health Studies) -- Queen's University, 2013-01-29 14:32:19.696

Objective: To develop modular software to assess angular impulse and to determine the effect of a reduced dataset on the net angular impulse acting at the L5/S1 joint. Background. With the prevalence and incidence of lower back pain increasing annually, accurate assessment of physical job demands is needed. Many lab based approaches exist to measure the moments acting on the lower back, but require advanced and sensitive testing equipment. Of the methodologies currently used in industrial settings, most require significant contributions of time or money to be implemented. There is a need for cost and time effective methods to record a worker’s kinematic data over their whole shift. Methods: Twelve participants performed 12 consecutive lifts under five lifting conditions: SQ00 (squat 0kg); SQ04 (squat 4kg); SQ10 (squat 10kg); FP04 (fast squat 4kg); ST04 (stoop 4kg). Kinematic data of the upper limbs, head, and trunk was recorded with external load data and kinetic analysis was performed by implementing an extension of the Hof (1992) method called the lined-segment engine (LSE) to calculate the angular impulse (N•m•s) acting on the L5/S1 joint. Results: The LSE was sensitive to changes in load, lifting speed, and lifting posture (p < 0.05). There was no difference in dynamic, quasi-static, or static models when calculating angular impulse, but there was a difference in the L5/S1 angular impulse when the upper limbs were removed from the dynamic LSE model (p < 0.05). Conclusion: The LSE requires further refinement, but could be a generic approach to kinetic calculations. A scaled no-arms model for calculating the angular impulse acting on the low back could be used to assess field based lifting studies with 5.8% error. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2013-08-03 15:05:03.257

ABSTRACT Aim: The aim of this study was to determine the most effective exercise program for the management of occupational lower back pain. Background: Occupational lower back pain accounts for 25% of workdays lost. The annual occurrence of occupational related lower back pain among blue collar workers in South Africa has shown to be between 55,7% and 63,9%. Methodology: Primary studies were searched with the use of the Entrez-cross-database search tool. Methodologies were assessed and critiqued. Data which included exercise detail, outcome measures of lower back pain intensity, painful episodes, sick leave and physical measures with statistical p-values was then extracted. Results: Nine primary studies, which included 11 exercise groups, complied to the inclusion and exclusion criteria. These studies proved to be of high methodology quality with quality scoring 70% on the quality assessment checklist. Exercise regimes, which included stretching, strengthening, endurance exercises and the combination use of stretching, strengthening and endurance exercises were identified and grouped according to the corresponding outcome measures. No meta-analysis could be done as no similar exercises with similar outcome measures could be found. Discussion: The limitations in the nine selected studies methodological quality were the lack of blinding of the assessors and subjects, and in six of the nine studies the lack of adequate participation rate among the intervention subjects. The validation process is acknowledged as a weakness within this study. Stretching, dynamic strengthening and endurance exercises were not statistically significant. Isometric exercise was statistically significant for lower back pain relief when the control group (p<0,0001) was compared to the experimental group. Isometric exercise however had no significant effect on abdominal strength at 9 months follow up period. Functionalexercises were statistically significant when the exercise group was compared to the control group with lower back pain intensity relief (p<0,018), painful episodes (p<0,018), sick leave (p< 0,0044). Functional exercises also had a long-term statistically significant effect on back muscle strength. A meta analysis could not be done due to insufficient similar studies. Conclusion: Although the methodology quality of the nine primary studies showed to be of high quality the validation process was a weakness within this study. Functional strengthening exercises were the most effective type of exercise for the management of occupational lower back pain among blue-collar workers. Future similar randomized control trials on exercise as an intervention to occupational lower back pain are needed to conduct a meta analysis. A meta analysis will be able to provide more evidence to establish which exercise regime is most effective for the management of occupational lower back pain.