Work-related musculoskeletal disorders (WMSDs), particularly overexertion injuries, represent a significant economic burden and involve substantial adverse personal outcomes. Two important contemporary changes in workforce demographics may be associated with an increase in the future incidence and cost of WMSDs. First, more than two-thirds of the US adult population is now either overweight or obese, a doubling of the prevalence of obesity over the past 30 years. Second, there has been a shift toward an older worker population, whose injuries often require more time away from work. Obesity and aging can modify job demands and affect worker capacity in terms of muscular and psychomotor function. However, there is a lack of empirical studies quantifying the work-relevant (or ergonomic) impacts related to task demands, capacities, and their potential imbalance. This research assessed obesity- and age-related differences in physical capacity by measuring localized muscle fatigue, endurance, and the effects of fatigue on psychomotor function. Three experiments were completed, progressing from controlled static to more complex intermittent and functional tasks. The work also examined whether obesity and age effects are modified by workplace/workstation configuration, specifically the extent to which body segment masses need to be supported. With obesity, strength was higher, but endurance time was lower, particularly for the more complex tasks. Interaction effects between obesity and age were seen in only a few measures across the studies and did not indicate a consistent effect. Outcomes of this research can facilitate the development of more effective (i.e., inclusive) guidelines to control WMSD risk and contribute to both proactive and reactive interventions to reduce excessive exposures to physical risk factors. Overall, the research goal is to help ensure that ergonomic guidelines and practice are appropriate (or are adapted) to accommodate the diverse and changing workforce. / Ph. D.

PURPOSE/BACKGROUND: Cryotherapy is commonly used in physical therapy with many known benefits; however several investigations have reported decreased functional performance following therapeutic application thereof. The purpose of this study was to determine the effect of cryotherapy applied to the ankle on static and dynamic standing balance. It was hypothesized that balance would be decreased after cryotherapy application. METHODS: Twenty individuals (aged 18 to 40 years) participated in this research project. Each participant was tested under two conditions: an experimental condition where subjects received ice water immersion of the foot and ankle for 15 minutes immediately before balance testing and a control condition completed at room temperature. A Biodex® Balance System was used to quantify balance using anterior/posterior (AP), medial/lateral (ML), and overall balance indices. Paired t-tests were used to compare the balance indices for the two conditions with alpha set at 0.05 a priori. Effect size was also calculated to account for the multiple comparisons made. RESULTS: The static balance indices did not display statistically significant differences between the post-cryotherapy and the control conditions with low effect sizes. Dynamic ML indices significantly increased following the cryotherapy application compared to the control exhibiting a moderate effect size indicating decreased balance following cryotherapy application. No differences were noted between experimental and control conditions for the dynamic AP or overall balance indices while a small effect size was noted for both. CONCLUSIONS: The results suggest that cryotherapy to the ankle has a negative effect on the ML component of dynamic balance following ice water immersion. CLINICAL RELEVANCE: Immediate return to play following cryotherapy application is cautioned given the decreased dynamic ML balance and potential for increased injury risk. LEVEL OF EVIDENCE: 3b Case-control study.

Contexto: O exercício físico faz parte do tratamento do diabetes mellitus tipo 2 (DM2), doença que possui maior prevalência na população idosa. Maior foco tem sido dado ao efeito do treinamento de força no controle glicêmico, sendo que menor número de estudos tem como desfecho primário parâmetros neuromusculares, em idosos com DM2. Objetivo: Avaliar os efeitos de um programa de treino de força nos parâmetros neuromusculares de idosos com DM2, em relação à um grupo controle. Delineamento: ensaio clínico randomizado, com dois grupos, intervenção (GI) e controle (GC). Métodos: Quarenta e quatro participantes foram alocados nos dois grupos: GI (n=22), que realizou treinamento de força três vezes por semana, durante 12 semanas; GC (n=22), que realizou uma sessão semanal de alongamento, durante 12 semanas. O treinamento de força foi composto por 11 exercícios, com 2-3 séries de 12-10 repetições e intensidade de 15 a 12 repetições máximas. O desfecho primário do estudo foi a qualidade muscular, por tensão específica e eco intensidade, que foi avaliada antes e após as 12 semanas, assim como os demais desfechos secundários. Os dados foram análises tanto pela intenção de tratar (ITT), como pela análise por protocolo (PP), baseado em 70% ou mais de comparecimento as seções. As comparações foram realizadas com Equação de Estimação Generalizadas e ANOVA de duas vias com medidas repetidas, para as análises ITT e PP, respectivamente. Resultados: Não houve modificação (p≥0,05) da qualidade muscular avaliada por eco intensidade ou por tensão específica, no GI e GC, para ambas as análises. Foram encontradas melhorias (p≤0,05) na força máxima dinâmica para o GI e GC na análise ITT e apenas para o GI na análise PP. Não foi encontrada diferença (p≥0,05) na força máxima isométrica, no GI e GC, em ambas as análises. Na análise ITT não foram encontradas melhorias (p≥0,05) no desempenho dos testes funcionais, para ambos os grupos, enquanto na análise PP houve redução (p≤0,05) no tempo de realização do teste timed up and go e subir escada no GC, e nos testes de sentar e levantar da cadeira e subir escada para o GI. Para a espessura muscular do quadríceps femoral houve aumento (p≤0,05) dos valores para o GI, mas não para o GC, em ambas as análises. Em relação a gordura visceral, não houve modificação dos valores em ambos os grupos com a análise ITT, mas houve redução (p≤0,05) com a análise PP, para os dois grupos. Os valores de hemoglobina glicada reduziram para o GI e aumentaram (p≤0,05) para o GC na análise PP, mas não foram encontradas diferenças (p≥0,05) para a análise ITT. Redução (p≤0,05) dos níveis de triglicerídeos foi encontrada para o GI, mas não para o GC, em ambas as análises. Conclusões: o programa de treino de força proposto no presente estudo foi capaz de melhorar a força dinâmica e a espessura muscular de idosos com DM2 no período de 12 semanas, mas não causou modificações significativas na qualidade muscular durante esse período, mostrando que para alguns parâmetros neuromusculares talvez seja necessário período maior de treinamento nessa população. / Context: Physical exercise is a cornerstone of diabetes mellitus type 2 (DM2) treatment, a disease that has a higher prevalence in the elderly population. Greater focus has been given to the effects of strength training on glycemic control, and a lower number of studies has investigated neuromuscular parameters as a primary endpoint in elderly with DM2. Objective: To evaluate the effects of a strength training program on the neuromuscular parameters of elderly patients with DM2, in relation to a control group. Design: Randomized clinical trial with intervention (GI) and control (CG) groups. Methods: Forty-four participants were randomized to both groups: GI (n= 22), which underwent strength training three times a week for 12 weeks, and GC (n = 22), which performed a weekly stretching session for 12 weeks. Strength training was composed of 11 exercises, with 2-3 sets of 12-10 repetitions and was set the intensity of 15 to 12 maximal repetitions. The primary outcome of the study was muscle quality measured by specific tension and eco intensity, evaluated before and after 12 weeks, as well as the other secondary outcomes. Data was analyzed by both, intention-to-treat (ITT) and per protocol (PP) analysis (based on 70% or more attendance sections). The comparisons were performed with Generalized Estimation Equation and two-way ANOVA with repeated measurements for ITT and PP analyzes, respectively. Results: No change (p≥0.05) in muscle quality assessed by echo intensity or by specific tension were found in GI and GC, in both analyzes. Increase (p≤0.05) in maximum dynamic strength was found for GI and GC in ITT analyze, but only for GI in PP analyze. No difference in maximum isometric force (p≥0.05) was found for GI and GC in both analysis. In the ITT analysis, there were no improvements (p≥0.05) in functional tests performance in both groups, whereas in the PP analysis reduction (p≤0.05) was found in the timed up and go and climb stairs tests in the GC, and in the sit to stand and climb stairs tests in the GI. Quadriceps femoris muscle thickness increased (p≤0.05) in GI in both analyzes, but not for GC. No difference was found for visceral fat, in both groups in the ITT analysis, but there was a reduction (p≤0.05) in the PP analysis for both groups, with no difference between groups. Glycated hemoglobin values was reduced (p≤0.05) in GI and significantly increased in GC in PP analysis, but no differences were found in ITT. Reduction (p≤0.05) in triglyceride levels was found in GI, but not in GC, in both analyzes. Conclusions: The strength training program used in this study was able to improve dynamic strength and muscle thickness of elderly patients with DM2 in the 12-week period, but it was not able to induce significant changes in muscle quality, indicating that for some neuromuscular parameters it may be required a longer period of training for this population.

This study investigated the impact of open heart surgery (Coronary Artery Bypass Graft, Heart Valve Replacement, or Left Ventricular Assist Device placement) on cognition, functional performance, and mood in the three months following surgery. The Montreal Cognitive Assessment (MoCA), Kettle Test (KT), Physical Self Maintenance Scale (PSMS), and Hospital Anxiety and Depression Scale (HD) measured global cognition, functional cognition, functional performance, and mood states, respectively. Thirteen male participants (ages 38 – 75) completed assessments at four time points -- when they were scheduled for surgery, within one week prior to surgery, before hospital discharge after surgery, and three months after surgery. ANOVA analyses were conducted on overall raw mean scores taken at these time points. Correlational analysis compared changes in cognition and functional performance of daily activities for this group. Effect size estimations and power analyses were conducted to estimate sample sizes needed for adequately powered subsequent study. Two measures (KT and PSMS) were adequately powered at 95% for the study sample. Functional cognition as measured by the KT improved significantly after surgery and surpassed baseline within three months after surgery. Functional performance as measured by the PSMS declined significantly after surgery but returned to baseline within three months after surgery. Global cognition as measured by the MoCA did not change, was not correlated with other measures, and was below norms at all time points. Mood states as measured by the HADS did not change and were above norms at all time points. This study had a small sample, only male participants, and one pooled group that did not allow for group comparisons. Two measures were self-reported, which may have impacted results due to responses biases. Despite these limitations, this is one of the first studies to track and compare both cognitive and functional performance changes over time. As such, this study may help practitioners and researchers improve and prioritize assessment and treatment options for individuals with cognitive and functional performance deficits after open heart surgery.

PURPOSE: To examine gluteus medius strength and endurance in relation to lower limb stability, targeting and agility. METHODS: 57 participants performed isometric and dynamic gluteus medius strength and endurance tests of both lower limbs. Lower limb dominance was determined using the Waterloo Footedness Questionnaire-Revised (WFQ-R). Strength and endurance of gluteus medius were compared to single-leg performance of a stork stand, a lateral foot targeting task and a hopping test of agility. RESULTS: Body mass normalized isometric gluteus medius strength was found to be weakly and inversely correlated to agility score for both dominant limbs (r=-0.262, p=0.026) and non-dominant limbs (r=-0.335, p=0.006) with a lower agility score indicating better agility performance. For non-dominant limbs only, body mass normalized isometric gluteus medius strength correlated negatively to targeting speed (r=-0.229, p=0.045) and isometric gluteus medius endurance measured as percentage drop in strength over time correlated weakly and positively to the amount of body sway demonstrated during a single-leg stork stand task (r=0.253, p=0.030). CONCLUSION: Gluteus medius strength may be weakly related to improved agility performance while gluteus medius endurance may weakly relate to improved single-leg static balance performance. It is likely that other factors such as neuromuscular training have a much larger influence on stability, targeting ability and agility than the strength and endurance of the hip abductors alone.

No description available.

Contexto: O exercício físico faz parte do tratamento do diabetes mellitus tipo 2 (DM2), doença que possui maior prevalência na população idosa. Maior foco tem sido dado ao efeito do treinamento de força no controle glicêmico, sendo que menor número de estudos tem como desfecho primário parâmetros neuromusculares, em idosos com DM2. Objetivo: Avaliar os efeitos de um programa de treino de força nos parâmetros neuromusculares de idosos com DM2, em relação à um grupo controle. Delineamento: ensaio clínico randomizado, com dois grupos, intervenção (GI) e controle (GC). Métodos: Quarenta e quatro participantes foram alocados nos dois grupos: GI (n=22), que realizou treinamento de força três vezes por semana, durante 12 semanas; GC (n=22), que realizou uma sessão semanal de alongamento, durante 12 semanas. O treinamento de força foi composto por 11 exercícios, com 2-3 séries de 12-10 repetições e intensidade de 15 a 12 repetições máximas. O desfecho primário do estudo foi a qualidade muscular, por tensão específica e eco intensidade, que foi avaliada antes e após as 12 semanas, assim como os demais desfechos secundários. Os dados foram análises tanto pela intenção de tratar (ITT), como pela análise por protocolo (PP), baseado em 70% ou mais de comparecimento as seções. As comparações foram realizadas com Equação de Estimação Generalizadas e ANOVA de duas vias com medidas repetidas, para as análises ITT e PP, respectivamente. Resultados: Não houve modificação (p≥0,05) da qualidade muscular avaliada por eco intensidade ou por tensão específica, no GI e GC, para ambas as análises. Foram encontradas melhorias (p≤0,05) na força máxima dinâmica para o GI e GC na análise ITT e apenas para o GI na análise PP. Não foi encontrada diferença (p≥0,05) na força máxima isométrica, no GI e GC, em ambas as análises. Na análise ITT não foram encontradas melhorias (p≥0,05) no desempenho dos testes funcionais, para ambos os grupos, enquanto na análise PP houve redução (p≤0,05) no tempo de realização do teste timed up and go e subir escada no GC, e nos testes de sentar e levantar da cadeira e subir escada para o GI. Para a espessura muscular do quadríceps femoral houve aumento (p≤0,05) dos valores para o GI, mas não para o GC, em ambas as análises. Em relação a gordura visceral, não houve modificação dos valores em ambos os grupos com a análise ITT, mas houve redução (p≤0,05) com a análise PP, para os dois grupos. Os valores de hemoglobina glicada reduziram para o GI e aumentaram (p≤0,05) para o GC na análise PP, mas não foram encontradas diferenças (p≥0,05) para a análise ITT. Redução (p≤0,05) dos níveis de triglicerídeos foi encontrada para o GI, mas não para o GC, em ambas as análises. Conclusões: o programa de treino de força proposto no presente estudo foi capaz de melhorar a força dinâmica e a espessura muscular de idosos com DM2 no período de 12 semanas, mas não causou modificações significativas na qualidade muscular durante esse período, mostrando que para alguns parâmetros neuromusculares talvez seja necessário período maior de treinamento nessa população. / Context: Physical exercise is a cornerstone of diabetes mellitus type 2 (DM2) treatment, a disease that has a higher prevalence in the elderly population. Greater focus has been given to the effects of strength training on glycemic control, and a lower number of studies has investigated neuromuscular parameters as a primary endpoint in elderly with DM2. Objective: To evaluate the effects of a strength training program on the neuromuscular parameters of elderly patients with DM2, in relation to a control group. Design: Randomized clinical trial with intervention (GI) and control (CG) groups. Methods: Forty-four participants were randomized to both groups: GI (n= 22), which underwent strength training three times a week for 12 weeks, and GC (n = 22), which performed a weekly stretching session for 12 weeks. Strength training was composed of 11 exercises, with 2-3 sets of 12-10 repetitions and was set the intensity of 15 to 12 maximal repetitions. The primary outcome of the study was muscle quality measured by specific tension and eco intensity, evaluated before and after 12 weeks, as well as the other secondary outcomes. Data was analyzed by both, intention-to-treat (ITT) and per protocol (PP) analysis (based on 70% or more attendance sections). The comparisons were performed with Generalized Estimation Equation and two-way ANOVA with repeated measurements for ITT and PP analyzes, respectively. Results: No change (p≥0.05) in muscle quality assessed by echo intensity or by specific tension were found in GI and GC, in both analyzes. Increase (p≤0.05) in maximum dynamic strength was found for GI and GC in ITT analyze, but only for GI in PP analyze. No difference in maximum isometric force (p≥0.05) was found for GI and GC in both analysis. In the ITT analysis, there were no improvements (p≥0.05) in functional tests performance in both groups, whereas in the PP analysis reduction (p≤0.05) was found in the timed up and go and climb stairs tests in the GC, and in the sit to stand and climb stairs tests in the GI. Quadriceps femoris muscle thickness increased (p≤0.05) in GI in both analyzes, but not for GC. No difference was found for visceral fat, in both groups in the ITT analysis, but there was a reduction (p≤0.05) in the PP analysis for both groups, with no difference between groups. Glycated hemoglobin values was reduced (p≤0.05) in GI and significantly increased in GC in PP analysis, but no differences were found in ITT. Reduction (p≤0.05) in triglyceride levels was found in GI, but not in GC, in both analyzes. Conclusions: The strength training program used in this study was able to improve dynamic strength and muscle thickness of elderly patients with DM2 in the 12-week period, but it was not able to induce significant changes in muscle quality, indicating that for some neuromuscular parameters it may be required a longer period of training for this population.

Contexto: O exercício físico faz parte do tratamento do diabetes mellitus tipo 2 (DM2), doença que possui maior prevalência na população idosa. Maior foco tem sido dado ao efeito do treinamento de força no controle glicêmico, sendo que menor número de estudos tem como desfecho primário parâmetros neuromusculares, em idosos com DM2. Objetivo: Avaliar os efeitos de um programa de treino de força nos parâmetros neuromusculares de idosos com DM2, em relação à um grupo controle. Delineamento: ensaio clínico randomizado, com dois grupos, intervenção (GI) e controle (GC). Métodos: Quarenta e quatro participantes foram alocados nos dois grupos: GI (n=22), que realizou treinamento de força três vezes por semana, durante 12 semanas; GC (n=22), que realizou uma sessão semanal de alongamento, durante 12 semanas. O treinamento de força foi composto por 11 exercícios, com 2-3 séries de 12-10 repetições e intensidade de 15 a 12 repetições máximas. O desfecho primário do estudo foi a qualidade muscular, por tensão específica e eco intensidade, que foi avaliada antes e após as 12 semanas, assim como os demais desfechos secundários. Os dados foram análises tanto pela intenção de tratar (ITT), como pela análise por protocolo (PP), baseado em 70% ou mais de comparecimento as seções. As comparações foram realizadas com Equação de Estimação Generalizadas e ANOVA de duas vias com medidas repetidas, para as análises ITT e PP, respectivamente. Resultados: Não houve modificação (p≥0,05) da qualidade muscular avaliada por eco intensidade ou por tensão específica, no GI e GC, para ambas as análises. Foram encontradas melhorias (p≤0,05) na força máxima dinâmica para o GI e GC na análise ITT e apenas para o GI na análise PP. Não foi encontrada diferença (p≥0,05) na força máxima isométrica, no GI e GC, em ambas as análises. Na análise ITT não foram encontradas melhorias (p≥0,05) no desempenho dos testes funcionais, para ambos os grupos, enquanto na análise PP houve redução (p≤0,05) no tempo de realização do teste timed up and go e subir escada no GC, e nos testes de sentar e levantar da cadeira e subir escada para o GI. Para a espessura muscular do quadríceps femoral houve aumento (p≤0,05) dos valores para o GI, mas não para o GC, em ambas as análises. Em relação a gordura visceral, não houve modificação dos valores em ambos os grupos com a análise ITT, mas houve redução (p≤0,05) com a análise PP, para os dois grupos. Os valores de hemoglobina glicada reduziram para o GI e aumentaram (p≤0,05) para o GC na análise PP, mas não foram encontradas diferenças (p≥0,05) para a análise ITT. Redução (p≤0,05) dos níveis de triglicerídeos foi encontrada para o GI, mas não para o GC, em ambas as análises. Conclusões: o programa de treino de força proposto no presente estudo foi capaz de melhorar a força dinâmica e a espessura muscular de idosos com DM2 no período de 12 semanas, mas não causou modificações significativas na qualidade muscular durante esse período, mostrando que para alguns parâmetros neuromusculares talvez seja necessário período maior de treinamento nessa população. / Context: Physical exercise is a cornerstone of diabetes mellitus type 2 (DM2) treatment, a disease that has a higher prevalence in the elderly population. Greater focus has been given to the effects of strength training on glycemic control, and a lower number of studies has investigated neuromuscular parameters as a primary endpoint in elderly with DM2. Objective: To evaluate the effects of a strength training program on the neuromuscular parameters of elderly patients with DM2, in relation to a control group. Design: Randomized clinical trial with intervention (GI) and control (CG) groups. Methods: Forty-four participants were randomized to both groups: GI (n= 22), which underwent strength training three times a week for 12 weeks, and GC (n = 22), which performed a weekly stretching session for 12 weeks. Strength training was composed of 11 exercises, with 2-3 sets of 12-10 repetitions and was set the intensity of 15 to 12 maximal repetitions. The primary outcome of the study was muscle quality measured by specific tension and eco intensity, evaluated before and after 12 weeks, as well as the other secondary outcomes. Data was analyzed by both, intention-to-treat (ITT) and per protocol (PP) analysis (based on 70% or more attendance sections). The comparisons were performed with Generalized Estimation Equation and two-way ANOVA with repeated measurements for ITT and PP analyzes, respectively. Results: No change (p≥0.05) in muscle quality assessed by echo intensity or by specific tension were found in GI and GC, in both analyzes. Increase (p≤0.05) in maximum dynamic strength was found for GI and GC in ITT analyze, but only for GI in PP analyze. No difference in maximum isometric force (p≥0.05) was found for GI and GC in both analysis. In the ITT analysis, there were no improvements (p≥0.05) in functional tests performance in both groups, whereas in the PP analysis reduction (p≤0.05) was found in the timed up and go and climb stairs tests in the GC, and in the sit to stand and climb stairs tests in the GI. Quadriceps femoris muscle thickness increased (p≤0.05) in GI in both analyzes, but not for GC. No difference was found for visceral fat, in both groups in the ITT analysis, but there was a reduction (p≤0.05) in the PP analysis for both groups, with no difference between groups. Glycated hemoglobin values was reduced (p≤0.05) in GI and significantly increased in GC in PP analysis, but no differences were found in ITT. Reduction (p≤0.05) in triglyceride levels was found in GI, but not in GC, in both analyzes. Conclusions: The strength training program used in this study was able to improve dynamic strength and muscle thickness of elderly patients with DM2 in the 12-week period, but it was not able to induce significant changes in muscle quality, indicating that for some neuromuscular parameters it may be required a longer period of training for this population.

Shoulder injuries often comprise two separate yet related components, structural tissue damage and pain. The role of each of these components on shoulder function is difficult to ascertain. Experimental pain models allow the assessment of consequences of localized pain when applied to healthy individuals. By understanding the role of pain on shoulder function, clinicians will be able to more efficiently assess and treat shoulder injuries. The objective of the study was to evaluate the role of experimentally-induced sub-acromial pain on shoulder isokinetic rotational strength and throwing accuracy. This was a block counterbalanced, crossover, repeated measures study design utilizing 20 individuals without self-reported shoulder or cervical pathology. Shoulder function was measured with and without experimental pain injection (2 mL of 5% hypertonic saline) in the sub-acromial space. Functional tasks consisted of shoulder rotational strength utilizing isokinetic testing and throwing accuracy via the functional throwing performance index. The hypertonic saline induced moderate pain levels in all participants (4.3-5.1/10). Normalized shoulder internal (t = 3.76, p = 0.001) and external (t = 3.12, p = 0.006) rotation strength were both diminished in the painful condition compared to the pain free condition. Throwing accuracy was also reduced while the participants experienced pain (t = 3.99, p = 0.001). Moderate levels of experimental shoulder pain were sufficient to negatively influence shoulder strength and throwing accuracy in participants without shoulder pathology.

No description available.