Effects of corn straw on meat characteristics of lambs in the Brazilian semi-arid region.

The present study aimed to evaluate the influence of increasing levels of corn straw replacement of sorghum silage on average daily gain, loin eye area, subcutaneous fat thickness, weight of commercial cuts, leg tissue composition, and physico-chemical characteristics of the meat from F1 Santa Inês × Dorper lambs maintained in a feedlot system. Treatments consisted of 0, 33, 66 and 100% corn straw replacement of sorghum silage. There were thirty-six 150-day-old male lambs. Corn straw replacement of sorghum silage in lamb feed reduced the average daily gain and weight of the ribs, besides promoting a quadratic influence on leg fat content. However, there was no influence on commercial carcass cuts, leg muscle index, leg tissue composition, and physico-chemical characteristics of the meat. Thus, corn straw can be used as alternative feedstuff for sheep rations to improve the production of high-quality sheep meat in semi-arid regions.

Carcass characteristics and meat quality of goats fed increasing levels of crude glycerin.

Crude glycerin is a byproduct of the biodiesel industry and has been widely used in ruminant diets as a source of energy, usually in place of corn, primarily during periods of drought in tropical regions. The objective of this study was to evaluate the effect of including levels of the crude glycerin of low purity (0, 6, 12 and 18%) replacing corn in the diets of goats on the carcass characteristics, tissue composition, meat cuts yield and physicochemical parameters of meat. Forty males castrated without defined racial pattern goats an initial average weight of 19.70 ± 2.30 kg were slaughtered after 86 days. Diets content 0 and 6% crude glycerin promoted similar responses to the analyzed variables, except for pH and breast weight. No differences were observed to total digestible nutrients, slaughter body weight, commercial cut yield leg tissue composition and physicochemical parameters of meat. Crude glycerin can be included up to 12% without losses on carcass weight and meat cuts, leg composition, and meat quality. The inclusion of crude glycerin containing 63.06% glycerol and 45.57% lipids could be effective in partial replacement of corn in diets for confined goats in tropical areas.

Reliability of different electromyographic normalization methods for pelvic floor muscles assessment.

AIMS: To evaluate the reliability of different methods to normalize pelvic floor muscles (PFM) electromyography (EMG). METHODS: Thirty nulliparous women (23.9 ± 3.2 years), free from PFM dysfunction, completed two test sessions 7 days apart. For EMG normalization, signals were acquired during four different tasks using a vaginal probe in situ: PFM maximal voluntary contraction (MVC) and three daily activities with increased intra-abdominal pressure (coughing, Valsalva maneuver, and abdominal contraction). The intraclass correlation coefficients (ICC), standard error of measurement (SEM), relative standard error of measurement (%SEM), and minimal detectable change (MDC) were calculated for each variable. RESULTS: ICC values for test-retest reliability of normalization methods ranged from 0.61 to 0.95. The highest values were obtained for mean root mean square (RMS) of the abdominal contraction and peak RMS of PFM-MVC. Normalization using RMS of PFM-MVC showed the lowest values of SEM and MDC. CONCLUSIONS: The normalization of EMG data is considered a fundamental part of EMG investigations. These findings suggest that the normalization of PFM-EMG by either peak RMS of PFM-MVC or mean and peak RMS of abdominal contraction has excellent reliability and it can be applied in studies involving the evaluation of young women.

Inspection Score and Grading System for Food Services in Brazil: The Results of a Food Safety Strategy to Reduce the Risk of Foodborne Diseases during the 2014 FIFA World Cup.

In 2014, Brazil hosted one of the most popular sport competitions in the world, the FIFA World Cup. Concerned about the intense migration of tourists, the Brazilian government decided to deploy a food safety strategy based on inspection scores and a grading system applied to food services. The present study aimed to evaluate the results of the food safety strategy deployed during the 2014 FIFA World Cup in Brazil. To assess food safety, an evaluation instrument was applied twice in 1927 food service establishments from 26 cities before the start of the competition. This instrument generated a food safety score for each establishment that ranged from 0.0 (no flaws observed) to 2565.95, with four possible grades: A (0.0-13.2); B (13.3-502.6); C (502.7-1152.2); and pending (more than 1152.3). Each food service received a stamp with the grade of the second evaluation. After the end of the World Cup, a study was conducted with different groups of the public to evaluate the acceptance of the strategy. To this end, 221 consumers, 998 food service owners or managers, 150 health surveillance auditors, and 27 health surveillance coordinators were enrolled. These participants completed a survey with positive and negative responses about the inspection score system through a 5-point Likert scale. A reduction in violation scores from 393.1 to 224.4 (p < 0.001) was observed between the first and second evaluation cycles. Of the food services evaluated, 38.7% received the A stamp, 41.4% the B stamp, and 13.9% the C stamp. All positive responses on "system reliability" presented a mean of 4.0 or more, indicating that the public believed this strategy is reliable for communicating risks and promoting food safety. The strategy showed positive results regarding food safety and public acceptance. The deployed strategy promoted improvements in the food safety of food services. The implementation of a permanent policy may be well accepted by the public and may greatly contribute to a reduction in foodborne diseases (FBDs).

Postural control during sit-to-stand movement and its relationship with upright position in children with hemiplegic spastic cerebral palsy and in typically developing children.

OBJECTIVE: The purpose of this study was to compare postural control in typically developing (TD) children and children with cerebral palsy (CP) during the sit-to-stand (STS) movement and to assess the relationship between static (during static standing position) and dynamic postural control (during STS movement) in both groups. METHOD: The center of pressure (CoP) behavior of 23 TD children and 6 children with spastic hemiplegic CP (Gross Motor Function Classification System [GMFCS] I and II) was assessed during STS movement performance and during static standing conditions with the use of a force plate. The data obtained from the force plate were used to calculate CoP variables: anteroposterior (AP) and mediolateral (ML) amplitudes of CoP displacement and the area and velocity of CoP oscillation. RESULTS: According to the Mann-Whitney test, children with CP exhibited higher CoP values in all of the analyzed variables during the beginning of STS movement. Pearson's correlation verified a positive correlation between the CoP variables during both static conditions and the performance of STS movement. CONCLUSIONS: Children with spastic hemiplegic CP present major postural oscillations during the beginning of STS movement compared with typical children. Moreover, the observed relationship between postural control in static and dynamic conditions reveals the importance of body control in the static position for the performance of functional activities that put the body in motion, such as STS movement.

Postural control during sit-to-stand movement and its relationship with upright position in children with hemiplegic spastic cerebral palsy and in typically developing children

OBJECTIVE: The purpose of this study was to compare postural control in typically developing (TD) children and children with cerebral palsy (CP) during the sit-to-stand (STS) movement and to assess the relationship between static (during static standing position) and dynamic postural control (during STS movement) in both groups. METHOD: The center of pressure (CoP) behavior of 23 TD children and 6 children with spastic hemiplegic CP (Gross Motor Function Classification System [GMFCS] I and II) was assessed during STS movement performance and during static standing conditions with the use of a force plate. The data obtained from the force plate were used to calculate CoP variables: anteroposterior (AP) and mediolateral (ML) amplitudes of CoP displacement and the area and velocity of CoP oscillation. RESULTS: According to the Mann-Whitney test, children with CP exhibited higher CoP values in all of the analyzed variables during the beginning of STS movement. Pearson's correlation verified a positive correlation between the CoP variables during both static conditions and the performance of STS movement. CONCLUSIONS: Children with spastic hemiplegic CP present major postural oscillations during the beginning of STS movement compared with typical children. Moreover, the observed relationship between postural control in static and dynamic conditions reveals the importance of body control in the static position for the performance of functional activities that put the body in motion, such as STS movement. .

Relationship among vaginal palpation, vaginal squeeze pressure, electromyographic and ultrasonographic variables of female pelvic floor muscles.

BACKGROUND: The proper evaluation of the pelvic floor muscles (PFM) is essential for choosing the correct treatment. Currently, there is no gold standard for the assessment of female PFM function. OBJECTIVE: To determine the correlation between vaginal palpation, vaginal squeeze pressure, and electromyographic and ultrasonographic variables of the female PFM. METHOD: This cross-sectional study evaluated 80 women between 18 and 35 years of age who were nulliparous and had no pelvic floor dysfunction. PFM function was assessed based on digital palpation, vaginal squeeze pressure, electromyographic activity, bilateral diameter of the bulbocavernosus muscles and the amount of bladder neck movement during voluntary PFM contraction using transperineal bi-dimensional ultrasound. The Pearson correlation was used for statistical analysis (p<0.05). RESULTS: There was a strong positive correlation between PFM function and PFM contraction pressure (0.90). In addition, there was a moderate positive correlation between these two variables and PFM electromyographic activity (0.59 and 0.63, respectively) and movement of the bladder neck in relation to the pubic symphysis (0.51 and 0.60, respectively). CONCLUSIONS: This study showed that there was a correlation between vaginal palpation, vaginal squeeze pressure, and electromyographic and ultrasonographic variables of the PFM in nulliparous women. The strong correlation between digital palpation and PFM contraction pressure indicated that perineometry could easily be replaced by PFM digital palpation in the absence of equipment.

Relationship among vaginal palpation, vaginal squeeze pressure, electromyographic and ultrasonographic variables of female pelvic floor muscles / Correlação entre palpação digital, pressão de contração, atividade eletromiográfica e variáveis ultrassonográficas da musculatura do assoalho pélvico feminino

Background: The proper evaluation of the pelvic floor muscles (PFM) is essential for choosing the correct treatment. Currently, there is no gold standard for the assessment of female PFM function. Objective: To determine the correlation between vaginal palpation, vaginal squeeze pressure, and electromyographic and ultrasonographic variables of the female PFM. Method: This cross-sectional study evaluated 80 women between 18 and 35 years of age who were nulliparous and had no pelvic floor dysfunction. PFM function was assessed based on digital palpation, vaginal squeeze pressure, electromyographic activity, bilateral diameter of the bulbocavernosus muscles and the amount of bladder neck movement during voluntary PFM contraction using transperineal bi-dimensional ultrasound. The Pearson correlation was used for statistical analysis (p<0.05). Results: There was a strong positive correlation between PFM function and PFM contraction pressure (0.90). In addition, there was a moderate positive correlation between these two variables and PFM electromyographic activity (0.59 and 0.63, respectively) and movement of the bladder neck in relation to the pubic symphysis (0.51 and 0.60, respectively). Conclusions: This study showed that there was a correlation between vaginal palpation, vaginal squeeze pressure, and electromyographic and ultrasonographic variables of the PFM in nulliparous women. The strong correlation between digital palpation and PFM contraction pressure indicated that perineometry could easily be replaced by PFM digital palpation in the absence of equipment. .

Contextualização: A avaliação adequada da musculatura do assoalho pélvico (MAP) é essencial para o delineamento do tratamento correto. No entanto, atualmente não existe um método de avaliação dessa região que seja considerado como padrão-ouro. Objetivo: Verificar a correlação entre a palpação digital, a pressão de contração, a atividade eletromiográfica e as variáveis ultrassonográficas da MAP. Método: Neste estudo transversal, foram avaliadas 80 mulheres com idades entre 18 e 35 anos, nulíparas e sem relatos de disfunção de assoalho pélvico. Foram avaliados a função muscular por meio da palpação digital, a pressão de contração, a atividade eletromiográfica, o diâmetro bilateral do músculo bulbocavernoso e o deslocamento do colo vesical em relação à sínfise púbica por meio da ultrassonografia bidimensional. Para a análise estatística, foi realizada a Correlação de Pearson (p<0,05). Resultados: Observou-se uma correlação positiva forte entre a função e a pressão de contração da MAP (0,90). Observou-se também uma correlação positiva moderada entre essas duas variáveis e a atividade eletromiográfica da MAP (0,59 and 0,63, respectivamente), bem como entre o deslocamento do colo vesical e a sínfise púbica (0.51 e 0.60, respectivamente). Conclusões: Os achados deste estudo permitem concluir que existe correlação entre as variáveis ultrassonográficas e a função muscular, a pressão de contração e a atividade eletromiográfica da MAP em mulheres jovens nulíparas. A correlação forte existente entre a palpação digital e a pressão de contração ...

30° inclination in handles of plastic boxes can reduce postural and muscular workload during handling.

BACKGROUND: The handling of materials, which occurs in the industrial sector, is associated with lesions on the lumbar spine and in the upper limbs. Inserting handles in industrial boxes is a way to reduce work-related risks. Although the position and angle of the handles are significant factors in comfort and safety during handling, these factors have rarely been studied objectively. OBJECTIVE: To compare the handling of a commercial box and prototypes with handles and to evaluate the effects on upper limb posture, muscle electrical activity, and perceived acceptability using different grips while handling materials from different heights. METHOD: Thirty-seven healthy volunteers evaluated the handles of prototypes that allowed for changes in position (top and bottom) and angle (0°, 15°, and 30°). Wrist, elbow, and shoulder movements were evaluated using electrogoniometry and inclinometry. The muscle electrical activity in the wrist extensors, biceps brachii, and the upper portion of the trapezius was measured using a portable electromyographer. The recorded data on muscle movements and electrical activity were synchronized. Subjective evaluations of acceptability were evaluated using a visual analog scale. RESULTS AND CONCLUSIONS: The prototypes with handles at a 30° angle produced the highest acceptability ratings, more neutral wrist positions, lower levels of electromyographic activity for the upper trapezius, and lower elevation angles for the arms. The different measurement methods were complementary in evaluating the upper limbs during handling.

Effects of short-term isokinetic training with reciprocal knee extensors agonist and antagonist muscle actions: a controlled and randomized trial.

BACKGROUND: Previous studies have shown that preloading an antagonist muscle may increase the acute agonist neuromuscular performance. In addition, studies have suggested that very short-term resistance exercise (RE) programs may also be useful to increase strength and muscular performance. OBJECTIVES: To evaluate the effects of three days of RE using a reciprocal action method on the muscular performance of healthy men and to compare these effects with those of a traditional RE group. METHOD: Thirty-three men (21.1 ± 2.3 years) were randomly assigned to one of three groups: 1) reciprocal (REC; knee flexion immediately followed by a knee extension exercise); 2) traditional (TRA; non-preload; a concentric knee extension exercise); and 3) control (CON; no exercise). The REC and TRA subjects performed four sets of 10 repetitions at 60º/s with one minute of rest. The pre- and post-RE tests included two sets of four maximal concentric repetitions at 60º/s and 180º/s. A 3x2 ANOVA with Tukey post-hoc was used to analyze the differences in peak torque (PT), rating of acceleration development (RAD) and time to peak torque (TIMEtorque). RESULTS: A significant PT increase was found for REC and TRA (p<0.05) at 60º/s and for REC at 180º/s (p<0.05). There was a decrease in the RAD for REC and TRA (p<0.05), and TIMEtorque showed a significant decrease for REC. The inter-group analysis revealed that REC is more effective than TRA for PT gains at both velocities (p<0.05). CONCLUSION: It is recommended that REC offers benefits for the clinical practice of professionals involved in neuromuscular rehabilitation.

30o inclination in handles of plastic boxes can reduce postural and muscular workload during handling

BACKGROUND: The handling of materials, which occurs in the industrial sector, is associated with lesions on the lumbar spine and in the upper limbs. Inserting handles in industrial boxes is a way to reduce work-related risks. Although the position and angle of the handles are significant factors in comfort and safety during handling, these factors have rarely been studied objectively. OBJECTIVE: To compare the handling of a commercial box and prototypes with handles and to evaluate the effects on upper limb posture, muscle electrical activity, and perceived acceptability using different grips while handling materials from different heights. METHOD: Thirty-seven healthy volunteers evaluated the handles of prototypes that allowed for changes in position (top and bottom) and angle (0°, 15°, and 30°). Wrist, elbow, and shoulder movements were evaluated using electrogoniometry and inclinometry. The muscle electrical activity in the wrist extensors, biceps brachii, and the upper portion of the trapezius was measured using a portable electromyographer. The recorded data on muscle movements and electrical activity were synchronized. Subjective evaluations of acceptability were evaluated using a visual analog scale. RESULTS AND CONCLUSIONS: The prototypes with handles at a 30° angle produced the highest acceptability ratings, more neutral wrist positions, lower levels of electromyographic activity for the upper trapezius, and lower elevation angles for the arms. The different measurement methods were complementary in evaluating the upper limbs during handling. .

Effects of short-term isokinetic training with reciprocal knee extensors agonist and antagonist muscle actions: A controlled and randomized trial / Effects of short-term isokinetic training with reciprocal knee extensors agonist and antagonist muscle actions: A controlled and randomized trial

BACKGROUND: Previous studies have shown that preloading an antagonist muscle may increase the acute agonist neuromuscular performance. In addition, studies have suggested that very short-term resistance exercise (RE) programs may also be useful to increase strength and muscular performance. OBJECTIVES: To evaluate the effects of three days of RE using a reciprocal action method on the muscular performance of healthy men and to compare these effects with those of a traditional RE group. METHOD: Thirty-three men (21.1 ± 2.3 years) were randomly assigned to one of three groups: 1) reciprocal (REC; knee flexion immediately followed by a knee extension exercise); 2) traditional (TRA; non-preload; a concentric knee extension exercise); and 3) control (CON; no exercise). The REC and TRA subjects performed four sets of 10 repetitions at 60º/s with one minute of rest. The pre- and post-RE tests included two sets of four maximal concentric repetitions at 60º/s and 180º/s. A 3x2 ANOVA with Tukey post-hoc was used to analyze the differences in peak torque (PT), rating of acceleration development (RAD) and time to peak torque (TIMEtorque). RESULTS: A significant PT increase was found for REC and TRA (p<0.05) at 60º/s and for REC at 180º/s (p<0.05). There was a decrease in the RAD for REC and TRA (p<0.05), and TIMEtorque showed a significant decrease for REC. The inter-group analysis revealed that REC is more effective than TRA for PT gains at both velocities (p<0.05). CONCLUSION: It is recommended that REC offers benefits for the clinical practice of professionals involved in neuromuscular rehabilitation. .

CONTEXTUALIZAÇÃO: Estudos demonstraram que a pré-ativação de músculos antagonistas pode aumentar o desempenho neuromuscular agonista. Além disso, estudos sugerem que programas de exercício resistido (ER) de curta duração podem ser úteis para aumentar a força muscular e o desempenho. OBJETIVOS: Avaliar os efeitos de três sessões de ER por meio do método de ações recíprocas no desempenho muscular de homens sadios e comparar com um grupo de ER tradicional. MÉTODO: Trinta e três homens (21,1 ± 2,3 anos) foram randomicamente alocados em três grupos: Recíproco (REC: uma repetição de flexão do joelho imediatamente seguida por uma de extensão do joelho); Tradicional (TRA: exercício concêntrico de extensão do joelho) e Controle (CON: não realizaram exercício). O REC e o TRA realizaram quatro séries de dez repetições a 60º.s-1 com um minuto entre séries. As avaliações pré e pós-ER foram caracterizadas por duas séries de quatro repetições máximas a 60º.s-1 e 180º.s-1. Utilizou-se ANOVA 3x2, com post-hoc de Tukey para verificar diferenças no pico de torque (PT), taxa de desenvolvimento de aceleração (TDA) e tempo para atingir o PT (TEMPtorque). RESULTADOS: Houve um aumento do PT para o REC e o TRA (p<0.05) a 60º.s-1 e apenas para o REC a 180º.s-1 (p<0,05). Houve diminuição da TDA para o REC e o TRA (p<0,05) e, apenas no REC, o TEMPtorque apresentou quedas significantes. A análise intergrupos mostrou que o REC foi mais efetivo que o TRA para os ganhos de PT em ambas as velocidades (p<0,05). CONCLUSÃO: Sugere-se que a modalidade recíproca seja vantajosa para ...

Shoulder internal and external rotations torque steadiness in overhead athletes with and without impingement symptoms.

OBJECTIVES: This study aimed to investigate torque steadiness of shoulder internal and external rotations in regularly training overhead athletes with and without impingement symptoms. DESIGN: Cross-sectional laboratory study. METHODS: Three groups were evaluated: athletes with impingement symptoms (n=21), asymptomatic athletes (n=25) and non-athletes (n=21). To assess torque steadiness, the participants performed 3 submaximal contractions (35% of peak torque) for 10s each, with the arm at 90° of shoulder abduction and 90° of external rotation. The standard deviation, coefficient of variation, mean exerted torque and time to stability were measured from the steadiness trials. RESULTS: The standard deviation of internal rotation was higher in asymptomatic athletes than in non-athletes (p<0.01); however, there was no difference between the athletes with impingement symptoms and the other groups. The other variables presented no differences among the groups. CONCLUSIONS: Higher torque fluctuation of shoulder internal rotation in asymptomatic athletes may point to neuromuscular adaptations related to throwing training. However, the steadiness patterns of athletes with impingement symptoms did not differ from those of asymptomatic athletes or non-athletes.

Are cutout handles used when available in real occupational settings? Description of grips and upper extremities movements during industrial box handling.

In order to achieve better postures and decrease musculoskeletal risks adequate design of hand/box couplings for manual materials handling (MMH) are still needed. No studies evaluating upper limb movement thorough direct measurements during box handling in workplace were identified in the literature. In this study we describe the types of grip and movements adopted by ten workers when handling redesigned boxes with cutout handles between different heights on industrial pallets. The new handles were used by 90% of the workers through different types of grip. Electrogoniometric measurements showed relatively safe forearm and wrist movements, although elbow inadequate range of movement was recorded. Despite the good acceptance of the cutout by workers, the new design requires extra internal space in the boxes reducing applications for this alternative of box.

How do low/high height and weight variation affect upper limb movements during manual material handling of industrial boxes? / Como a variação de altura e massa da carga afetam os movimentos do membro superior durante o manuseio de caixas industriais?

OBJECTIVES: To evaluate the effect of surface height and load weight on upper limb movements and electromyographic (EMG) recordings during manual handling performed by both experienced and inexperienced lifter subjects. METHODS: Sixteen experienced and sixteen inexperienced lifters handled a box (both 7 and 15 kg) from an intermediate height (waist level) to either a high or low surface. Electromyography and video images were recorded during the tasks. The 10th, 50th and 90th percentiles were calculated for the deltoid and biceps muscles, shoulder flexion, shoulder abduction, and elbow flexion movements. Groups, right/left sides, weights and heights were compared. There were no differences between either groups or sides. RESULTS: Weight and height variations affected EMG and posture, although weight had more impact on EMG. Shoulder abduction and flexion movements higher than 60º occurred, particularly for the higher surface. Shoulder flexion was also higher when the box was moved to the low height. This study provides new evidence as shoulder postures during boxes handling on low surfaces had not previously been evaluated. CONCLUSIONS: The high demand of upper limb in manual material handling tasks is clear, particularly for the shoulder. This knowledge can be used by physical therapists to plan better rehabilitation programs for manual material handling-related disorders, particularly focusing on return to work.

OBJETIVOS: Avaliar o efeito da altura de superfície e massa da carga nos movimentos e na atividade eletromiográfica (EMG) dos membros superiores durante o manuseio de carga realizado por sujeitos experientes e inexperientes. MÉTODOS: Dezesseis sujeitos experientes e 16 inexperientes manusearam uma caixa (7 e 15 kg) de uma superfície com altura intermediária para uma superfície alta e/ou baixa. Durante as tarefas, foram registradas imagens de vídeo e EMG. Os dados foram processados para obtenção dos percentis 10, 50 e 90 referentes à EMG dos músculos deltoide e bíceps e aos movimentos de flexão e abdução do ombro e flexão do cotovelo. Foram comparados os grupos, lados (direito/esquerdo), massas e altura de manuseio. RESULTADOS: Não foram encontradas diferenças significantes entre os grupos ou lados. As variações de massa e altura de manuseio afetaram a EMG e postura, embora a massa da caixa tenha tido mais impacto sobre a EMG. Os movimentos de abdução e flexão do ombro ocorreram acima de 60º, particularmente no manuseio para a superfície alta. A amplitude de flexão de ombro também foi alta quando a caixa foi movida para a superfície baixa. Esse resultado consiste em uma nova evidência, já que posturas do ombro durante o manuseio de carga em superfícies baixas não tinham sido investigadas. CONCLUSÕES: A alta demanda do membro superior em tarefas de manuseio de carga é clara, particularmente do ombro. Esse conhecimento pode ser usado por fisioterapeutas para um melhor planejamento da reabilitação de lesões relacionadas ao manuseio de cargas, visando o retorno ao trabalho.

Functional torque ratios and torque curve analysis of shoulder rotations in overhead athletes with and without impingement symptoms.

In this study, we evaluated the peak torque, functional torque ratios, and torque curve profile of the shoulder rotators in overhead athletes with impingement symptoms so as to examine possible alterations in response to sports training and shoulder pain. Twenty-one overhead athletes with impingement symptoms were compared with 25 overhead athletes and 21 non-athletes, none of whom were symptomatic for impingement. The participants performed five maximal isokinetic concentric and eccentric contractions of medial and lateral shoulder rotations at 1.57 rad · s(-1) and 3.14 rad · s(-1). Isokinetic peak torque was used to calculate the eccentric lateral rotation-to-concentric medial rotation and the eccentric medial rotation-to-concentric lateral rotation ratios. An analysis of the torque curve profiles was also carried out. The eccentric lateral rotation-to-concentric medial rotation torque ratio of asymptomatic athletes was lower than that of non-athletes at both test velocities. The concentric medial rotation isokinetic peak torque of the asymptomatic athletes, at 3.14 rad · s(-1), was greater than that of the non-athletes, and the peak appeared to occur earlier in the movement for athletes than non-athletes. These findings suggest that there may be adaptations to shoulder function in response to throwing practice. The eccentric medial rotation-to-concentric lateral rotation torque ratio was altered neither by the practice of university-level overhead sports nor impingement symptoms.

How do low/high height and weight variation affect upper limb movements during manual material handling of industrial boxes?

OBJECTIVES: To evaluate the effect of surface height and load weight on upper limb movements and electromyographic (EMG) recordings during manual handling performed by both experienced and inexperienced lifter subjects. METHODS: Sixteen experienced and sixteen inexperienced lifters handled a box (both 7 and 15 kg) from an intermediate height (waist level) to either a high or low surface. Electromyography and video images were recorded during the tasks. The 10th, 50th and 90th percentiles were calculated for the deltoid and biceps muscles, shoulder flexion, shoulder abduction, and elbow flexion movements. Groups, right/left sides, weights and heights were compared. There were no differences between either groups or sides. RESULTS: Weight and height variations affected EMG and posture, although weight had more impact on EMG. Shoulder abduction and flexion movements higher than 60º occurred, particularly for the higher surface. Shoulder flexion was also higher when the box was moved to the low height. This study provides new evidence as shoulder postures during boxes handling on low surfaces had not previously been evaluated. CONCLUSIONS: The high demand of upper limb in manual material handling tasks is clear, particularly for the shoulder. This knowledge can be used by physical therapists to plan better rehabilitation programs for manual material handling-related disorders, particularly focusing on return to work.

Isokinetic dynamometry applied to shoulder rotators - velocity limitations in eccentric evaluations.

The objectives of this study were to evaluate if collegiate overhead athletes, with and without shoulder pain, and non-athletes could reach a preset velocity in internal and external shoulder rotation isokinetic evaluations; and to evaluate the correlation between torque and velocity. Controlled laboratory study, cross-sectional. Evaluations were performed using the isokinetic dynamometer Biodex System 3. Participants were assessed seated, with the arm at 90° of shoulder abduction and 90° of elbow flexion, from neutral rotation to 90° of external rotation. Five maximal contractions of isokinetic concentric and reactive eccentric internal and external rotation were performed at the velocities 90°/s, 180°/s and 240°/s. Data were processed with using MatLab. Most participants did not reach the isokinetic phase during eccentric tests at 180°/s and 240°/s, particularly in the external rotators evaluation. High correlations between torque and velocity of eccentric tests were found. The groups presented no differences in maximal velocity attained in trials which preset velocity was not reached. These results call into question the use of reactive eccentric tests at velocities higher than 180°/s for the isokinetic evaluation of shoulder external rotators in collegiate overhead athletes and non-athletes in this specific position. In such cases, careful evaluation of the velocity is recommended to determine if the isokinetic phase was reached.