Work-related musculoskeletal disorders (WMSDs) negatively impact worker's health, ability to work, and their quality of life. Non-invasive methods for assessing the physiological responses to workload may provide information on physiological markers leading to increased risk of WMSDs. The following study aimed to evaluate the feasibility of using thermography to quantify differences in thermal readings of participants during and following a data entry task and assess the repeatability of thermal readings. Skin surface temperature measurements of the dorsal forearm were obtained from 12 participants (6 females, 6 males) during a data entry task (35 minutes) and a 30-minute post-task period. Participants also reported their perceived forearm discomfort during data entry and recovery. Three forearm analysis regions were analyzed based on statistical findings; Upper Left, Lower Left and Right regions. Temperature trends were found to increase during data entry and decrease during recovery. The Upper Left region was warmer during both data entry and recovery phases in comparison to the other regions. Repeatability of surface temperatures, based on intraclass correlations (ICCs), was found to be fair for magnitudes and trends during data entry, and poor for magnitudes and trends during recovery, despite higher significant correlations in the latter. Positive correlations were evident between subjective feelings of forearm discomfort trends and temperature trends in response to workload. No gender differences were found with regard to temperature measurements. This work contributes to the understanding of surface responses of the forearm during and following an applied stress, and to the literature supporting thermography as a non-invasive evaluative tool for assessing physiological responses during job tasks. / Master of Science

O objetivo deste estudo foi comparar a resposta do vascular durante o teste de estresse mental em adultos sedentários (SED) e fisicamente ativos (FA) com apneia obstrutiva do sono (AOS). Os pacientes não tratados com AOS e sem outras comorbidades foram classificados em SED e FA de acordo com o Questionário Internacional de atividade física. A pressão sanguínea, a freqüência cardíaca, o fluxo sanguíneo do antebraço (FSA) (pletismografia) e a condutância vascular do antebraço (CVA = FSA/pressão sanguínea x 100) foram medidas continuamente em repouso (4 min), seguidas de 3 min do teste Stroop Color Word Test (SCWT) também conhecido como teste de estresse mental. Quarenta pacientes com AOS (homens = 24, idade = 50 ± 1 anos, índice de massa corporal = 29 ± 0,5 Kg/m2, índice de apneia hipopnéia = 39 ± 4 eventos/h) divididos em SED (n = 21) e FA (n = 19) apresentaram diferença significativa na quantidade de tempo gasto em atividade física (17 ± 9 vs. 245 ± 33 minutos/semana, respectivamente). Os grupos foram semelhantes em relação ao sexo, idade, índice de massa corporal, frequência cardíaca do nível educacional e pressão arterial média em repouso, bem como percepção de estresse no final do SCWT. Em contraste, FSA basal (1,7 ± 0,08 mL/min/100mL vs 2,5 ± 0,19 mL/min/100mL) e CVA (1,7 ± 0,07 vs 2,5 ± 0,2) foram significativamente menores no grupo SED quando comaprados a FA, respectivamente (p <0,05). A resposta de frequência cardíaca e pressão arterial ao SCWT foram semelhantes e aumentou em ambos os grupos. O FSA (3,5 ± 0,2 mL/min/100mL vs 2,4 ± 0,14 mL/min/100mL) e a CVA (3,5 ± 0,2 vs 2,3 ± 0,1) durante SCWT foi significativamente menor no grupo SED quando comparados ao grupo FA (P <0,05). Houve uma correlação significativa entre a atividade física no tempo de lazer e FSA (r = 0,57; P <0,05) e CVA (r = 0,48; P <0,05). Conclui-se, que, a resposta vascular nos pacientes com AOS é influenciada pelo nível de atividade física de lazer. O alto nível de atividade física pode proteger a disfunção cardiovascular em repouso e na condição de estresse mental em pacientes com AOS moderado a severo / The objective of this study was to compare a vascular response during the mental stress test in sedentary (SED) and physically active (PA) patients with obstructive sleep apnea (OSA). Patients not treated with OSA and without other comorbidities were classified in SED and PA according to the International Questionnaire of Physical Action. Blood pressure, heart rate, forearm blood flow (plethysmography) and forearm vascular conductance (FVC = FBF / blood pressure x 100) were measured continuously at rest (4 min), followed by 3 min of the test Stroop Color Word Test (SCWT) also known as mental stress test. Forty patients with OSA (men = 24, age = 50 ± 1 years, body mass index = 29 ± 0.5 kg / m2, apnea hypopnea index = 39 ± 4 events / h) divided in SED (n = 19) and PA (n = 19) presented a significant difference in the amount of time spent in physical activity (17 ± 9 vs. 245 ± 33 minutes / week, respectively). The groups are similar in relation to gender, age, body mass index, heart rate at educational level, and mean resting blood pressure, as well as perceived stress at the end of SCWT. In contrast, baseline FBF (1.7 ± 0.08 mL/min/100mL vs 2.5 ± 0.19 mL/min/100mL) and FVC (1.7 ± 0.07 U vs 2.5 ± 0.2 U) were significantly lower without SED group when compared to PA, respectively (p <0.05). The heart rate and blood pressure response to SCWT were similar and increased in both groups. The FBF (3.5 ± 0.2 mL/min/100mL vs 2.4 ± 0.14 mL/min/100mL) and the FVC (3.5 ± 0.2 U vs 2.3 ± 0.1 U) during SCWT was much lower in the SED group when compared to the group PA (P <0.05). There was a significant correlation between physical activity without leisure time and FBF (r = 0.57, P <0.05) and FVC (r = 0.48, P <0.05). In conclusion, the vascular response in OSA patients is influenced by the level of leisure physical activity. The high level of physical activity may protect a cardiovascular dysfunction at rest and mental stress condition in patients with moderate to severe OSA

Introduction: The forearm is a complex biological unit, which has allowed man's evolution. This PhD commenced with an analysis of the normal biomechanical functioning of the key components of the forearm: notably the distal radioulnar joint (DRUJ), interosseous ligament (IOL) and proximal radioulnar joint (PRUJ). Understanding normal forearm physiology, a clinical study followed to delineate the pathophysiology of a new clinical entity, related to DRUJ dysfunction. Methods: Biomechanical Study: A biomechanical testing jig was developed to facilitate collection of data about normal functioning of the DRUJ, IOL and PRUJ in both unloaded and loaded states. This permitted testing throughout the range of forearm pronosupination. Thawed fresh frozen cadaveric upperlimbs were mounted into the jig. Using Microstrain® strain gauges and Tekscan™ pressure sensors, the functional anatomy of the key components of the forearm was delineated, both with the forearm flexed at 90° and maximally extended at the elbow. Clinical Study: A series of 3-Tesla MRI scans was undertaken on patients symptomatic of an intermittent ulnar neuropathy. The causative pathophysiology was determined using 3D qualitative and quantitative analyses. Results: Biomechanical Study: Reproducible patterns of force transmitted and joint contact area have been determined for the DRUJ, and for the first time, the PRUJ. With the exception of PMax and P60 for the PRUJ, application of load increases contact areas and transmitted forces across the joints (P<0.05). The converse is true for PMax and P60 in the PRUJ. The IOL is lax during pronation, strain gradually increasing as the arm moves to neutral. In neutral the middle-portion of the IOL (m-IOL) demonstrates most strain, this decreasing again in supination, whilst the distal and proximal portions (d- & p-IOL) exhibit more strain (P<0.05). Axial loading consistently increases strain in all ligaments (P<0.05). Observed behaviour patterns across the joints and in the ligaments alter with elbow extension (P<0.05). Clinical Study: Salient symptoms of the new syndrome were described. Displacement of the ulnar nerve from its normal course was seen with compression/distraction in the distal forearm and Guyon’s canal. This was considered causative of the syndrome. As a by-product of the research, a new clinical device was also developed, which improves the patient pathway when investigating DRUJ dysfunction. Conclusions and Outcomes: This research has analysed normal forearm biomechanics determining that the PRUJ is a load-bearing joint, interrelated with the DRUJ and IOL. Elbow extension has been shown to alter the normal biomechanics of the forearm. A clinical entity of a dysfunctional forearm has been defined, called subluxation-related ulnar neuropathy or SUN syndrome. Finally, a new clinical device has been developed, which it is anticipated will translate into visible improvements in patient care.

O objetivo deste estudo foi comparar a resposta do vascular durante o teste de estresse mental em adultos sedentários (SED) e fisicamente ativos (FA) com apneia obstrutiva do sono (AOS). Os pacientes não tratados com AOS e sem outras comorbidades foram classificados em SED e FA de acordo com o Questionário Internacional de atividade física. A pressão sanguínea, a freqüência cardíaca, o fluxo sanguíneo do antebraço (FSA) (pletismografia) e a condutância vascular do antebraço (CVA = FSA/pressão sanguínea x 100) foram medidas continuamente em repouso (4 min), seguidas de 3 min do teste Stroop Color Word Test (SCWT) também conhecido como teste de estresse mental. Quarenta pacientes com AOS (homens = 24, idade = 50 ± 1 anos, índice de massa corporal = 29 ± 0,5 Kg/m2, índice de apneia hipopnéia = 39 ± 4 eventos/h) divididos em SED (n = 21) e FA (n = 19) apresentaram diferença significativa na quantidade de tempo gasto em atividade física (17 ± 9 vs. 245 ± 33 minutos/semana, respectivamente). Os grupos foram semelhantes em relação ao sexo, idade, índice de massa corporal, frequência cardíaca do nível educacional e pressão arterial média em repouso, bem como percepção de estresse no final do SCWT. Em contraste, FSA basal (1,7 ± 0,08 mL/min/100mL vs 2,5 ± 0,19 mL/min/100mL) e CVA (1,7 ± 0,07 vs 2,5 ± 0,2) foram significativamente menores no grupo SED quando comaprados a FA, respectivamente (p <0,05). A resposta de frequência cardíaca e pressão arterial ao SCWT foram semelhantes e aumentou em ambos os grupos. O FSA (3,5 ± 0,2 mL/min/100mL vs 2,4 ± 0,14 mL/min/100mL) e a CVA (3,5 ± 0,2 vs 2,3 ± 0,1) durante SCWT foi significativamente menor no grupo SED quando comparados ao grupo FA (P <0,05). Houve uma correlação significativa entre a atividade física no tempo de lazer e FSA (r = 0,57; P <0,05) e CVA (r = 0,48; P <0,05). Conclui-se, que, a resposta vascular nos pacientes com AOS é influenciada pelo nível de atividade física de lazer. O alto nível de atividade física pode proteger a disfunção cardiovascular em repouso e na condição de estresse mental em pacientes com AOS moderado a severo / The objective of this study was to compare a vascular response during the mental stress test in sedentary (SED) and physically active (PA) patients with obstructive sleep apnea (OSA). Patients not treated with OSA and without other comorbidities were classified in SED and PA according to the International Questionnaire of Physical Action. Blood pressure, heart rate, forearm blood flow (plethysmography) and forearm vascular conductance (FVC = FBF / blood pressure x 100) were measured continuously at rest (4 min), followed by 3 min of the test Stroop Color Word Test (SCWT) also known as mental stress test. Forty patients with OSA (men = 24, age = 50 ± 1 years, body mass index = 29 ± 0.5 kg / m2, apnea hypopnea index = 39 ± 4 events / h) divided in SED (n = 19) and PA (n = 19) presented a significant difference in the amount of time spent in physical activity (17 ± 9 vs. 245 ± 33 minutes / week, respectively). The groups are similar in relation to gender, age, body mass index, heart rate at educational level, and mean resting blood pressure, as well as perceived stress at the end of SCWT. In contrast, baseline FBF (1.7 ± 0.08 mL/min/100mL vs 2.5 ± 0.19 mL/min/100mL) and FVC (1.7 ± 0.07 U vs 2.5 ± 0.2 U) were significantly lower without SED group when compared to PA, respectively (p <0.05). The heart rate and blood pressure response to SCWT were similar and increased in both groups. The FBF (3.5 ± 0.2 mL/min/100mL vs 2.4 ± 0.14 mL/min/100mL) and the FVC (3.5 ± 0.2 U vs 2.3 ± 0.1 U) during SCWT was much lower in the SED group when compared to the group PA (P <0.05). There was a significant correlation between physical activity without leisure time and FBF (r = 0.57, P <0.05) and FVC (r = 0.48, P <0.05). In conclusion, the vascular response in OSA patients is influenced by the level of leisure physical activity. The high level of physical activity may protect a cardiovascular dysfunction at rest and mental stress condition in patients with moderate to severe OSA

Master of Science / Department of Electrical and Computer Engineering / Steven Warren / Handgrip contractions are a useful exercise for assessing muscle fatigue in the forearm musculature. Most conventional hand-forearm ergometer systems require the researcher to manually guide subject activity, collect subject data, and assess subject fatigue after it has occurred. Since post-processing tools are not standardized for this type of experiment, researchers resort to building their own tools. This process can make comparing results between research groups difficult. This thesis presents updates to a hand-forearm ergometer system that automate the control, data-acquisition, and data-analysis mechanisms. The automated system utilizes a LabVIEW virtual instrument as the system centerpiece; it provides the subject/researcher interfaces and coordinates data acquisition from both traditional and new sensors. The system also processes the hand-forearm data within the LabVIEW environment as the data are collected. This allows the researcher to better understand the onset of subject fatigue while an experiment is in progress. System upgrades relative to prior work include the addition of new parameters to the researcher display, a change in the subject display from a binary up-down display to a sliding bar for better control over subject grip state, and a software update from a simple data acquisition and display system to a real-time processing system. The toolset has proven to be a viable support resource for experimental studies performed in the Kansas State University Human Exercise Physiology Laboratory that target muscle fatigue in human forearms. Initial data acquired during these tests indicate the viability of the system to acquire consistent and physiologically meaningful data while providing a useable toolset for follow-on data analyses.

Bibliographische Beschreibung Krupnik, Viktoria Koordination zwischen Atmung und rhythmischen Unterarm-Trackingbewegungen bei unterschiedlichen mentalen Bedingungen der Trackingaufgabe Universität Leipzig, Dissertation 55 Seiten, 49 Lit., 9 Abb., 2 Tab., 1 Artikel Referat: Präzisionsbewegungen kommt eine steigende Rolle im täglichen Leben zu, z.B. bei der Bedienung von Smartphones und Computern. Sie unterliegen, wie alle motorischen Aktionen, der Koordination. Koordination bezeichnet die gegenseitige Beeinflussung des zeitlichen Ablaufs gleichzeitig ablaufender motorischer Prozesse, welche die Verschmelzung zu einem gemeinsamen Rhythmus oder die Einstellung stabiler Frequenz- bzw. Phasenbeziehungen zur Folge hat. Von besonderem Interesse ist die Koordination intendierter Bewegungen mit der stetig ablaufenden Atmung, die die Funktionsziele beider Prozesse beeinträchtigen kann. Wir untersuchten Atmungs-Bewegungs-Koordination (MRC) bei visuell geführten Folgebewegungen des Unterarms unter zwei hauptsächlichen Fragestellungen: a) Beeinträchtigt MRC die Genauigkeit der Folgebewegung? b) Wie beeinflussen erhöhte Genauigkeitsanforderung, Üben und aufgabenbezogene Belastung die Stärke der MRC? Ausgangshypothese war, dass die Folgegenauigkeit durch MRC verschlechtert wird. Außerdem vermuteten wir, dass die Stärke der MRC durch erhöhte Aufmerksamkeit und wiederholtes Üben verstärkt, durch höhere aufgabenspezifische Belastung (höhere Komplexität der Bewegung) dagegen verringert wird. 35 Probanden führten 8 Versuche unter verschiedenen Bedingungen durch: positive (gleichsinnige) Signal- Response-Beziehung (SRR), negative (gegensinnige) SRR als aufgabenbezogene Belastung, strenge (Leistungsanforderung) und weniger strenge (lockere) Instruktion. Die Versuche mit positiver und negativer SRR wurden zur Untersuchung von Übungseffekten je dreimal vorgenommen. Während die Stärke der MRC unter allen Bedingungen gleich blieb, variierte das Phasenkopplungsmuster. Unter positiver SRR und weniger strenger Instruktion wurde eine bestimmte Phasenbeziehung zur Atemperiode bevorzugt. Bei negativer SRR und strenger Instruktion zeigte sich ein engeres Kopplungsmuster mit zwei bevorzugten Phasenbeziehungen zur Atemperiode. MRC verbesserte die Folgegenauigkeit unter allen Versuchsbedingungen mit Ausnahme derjenigen mit lockerer Instruktion. Zur Verbesserung der Folgegenauigkeit trug vor allem ein geringerer Amplitudenfehler bei. Die Ergebnisse zeigen, dass erhöhte Konzentration die Phasenkopplung zwischen Folgebewegungen und Atmung verstärkt und die MRC-bedingte Verbesserung der Folgegenauigkeit weiter steigert.

A number of investigators have examined psychological stress-induced endothelial dysfunction, however, the underlying mechanisms for these responses have not been clearly elucidated. The purpose of this study was to compare the effects of mental challenge on forearm blood flow, total antioxidant capacity (a measure of oxidative stress), the release of norepinephrine (NE; stress induced neurotransmitter), and pro-inflammatory cytokine responses [both lipopolysaccharide (LPS)-stimulated TNF-α and IL-6 cytokine and mRNA] in lean and obese individuals. Twelve subjects who had a BMI above 30 kg/m2 and were above 30% body fat were categorized as obese and twelve subjects with a BMI below 25 kg/m2 and were below 25% body fat were categorized as lean subjects. Blood samples were drawn and forearm blood flow was assessed prior to and following subjects’ participation in a mental challenge protocol consisting of a computer-based Stroop Color-Word task and mental arithmetic task, for a total of 20 minutes. The mental challenge elicited an elevation in HR and NE in both the lean and obese groups. Furthermore, both lean and obese groups demonstrated an increase in FBF following the mental challenge, whereas no changes in total antioxidant capacity were observed. In addition, the lean group exhibited an increase in LPS-stimulated TNF-α cytokine production from baseline to following the mental challenge, whereas the obese group demonstrated a decrease in LPS-stimulated TNF-α cytokines. This corresponded with a decrease in LPS-stimulated TNF-α mRNA expression in the obese group, although the obese subjects maintained higher levels of both measurements (LPS-stimulated TNF-α cytokine and mRNA expression) compared with the lean group. Furthermore, in the LPS-stimulated IL-6 cytokine response, the obese group demonstrated a greater increase than the lean group following the mental challenge, even though both groups showed an increase in LPS-stimulated IL-6 mRNA expression. These findings suggest that the magnitude and direction of LPS-stimulated TNF-α cytokine response and mRNA expression and LPS-stimulated IL-6 cytokine response to acute stress may be dependent upon the effects of the additional percentage of body fat seen in obese individuals.

Title: Effect of strength training with vascular occlusion on the forearm flexor muscle strength. Aims: The aim is to determine the effect of vascular occlusion on maximum isometric strength of forearm muscles. Methodology: The research group of 8 volunteers underwent six weeks of exercise program for upper limb (UL). The exercise program was different for each upper limb. Probands practiced one UL with vascular occlusion and second one without vascular occlusion. The research group was measured maximal isometric strength of forearm muscles before the 6-week exercise block, after 3 weeks of training and after completion of the cycle. All measurements were carried out in the laboratory climbing walls FTVS UK. The results were statistically evaluated using test ANOVA with repeated measurement. Results: The results of examining the impact of vascular occlusion to increase muscle strength flexor forearm in this thesis confirmed. Testing did not find significant differences in absolute strength or relative strength between exercise with vascular occlusion and exercise without vascular occlusion. Absolute strength at exercise with vascular occlusion averaged before exercise program 422 N, after the completion of 461 N. Absolute strength at exercise without vascular occlusion averaged before exercise...

Title: Discrimination of EMG signals from individual forearm muscles from surface EMG Abstract: Location of electrodes for sensing the forearm muscles using surface electromyography is not accurately described. It is based only on recommendations by various authors in making researches. The aim of this study was to determine the optimal placement of electrodes on the forearm and describe it to another repeatable measurements. By analyzing the amplitude of EMG recording is confirmed not only the optimal location of electrodes, but either suggested muscle synergies that are possible to analyze more deeply in other studies because a detailed examination of muscle synergies are considerable application in upper limb prosthetics Keywords: Surface electromyography, forearm muscles, amplitude analysis

<p><strong>Introduction:</strong> A complex interaction between muscles, tendons, bones, joints and nerves are required for optimal function of the human hand. It is known that an individual’s grip strength is vital for performance of physical demanding tasks such as strength training with free weights. Strength training including a thicker grip around the bar may enhance the strength of the grip in the athlete without other special routines for grip strength development. The purpose of this investigation was to examine the difference in performance in multiple repetitions in two strength training exercises using two different sizes on the bar, to look for correlations between grip strength of the subjects hand and the amount of repetitions executed with two different size of the bar and finally the correlation of hand size and the amount of repetitions executed with two different size of the bar.</p><p><strong>Method:</strong> 15 strength training men (23,9 ± 4,1 years), underwent measurements of hand size, maximum grip strength, 1 repetition maximum (1RM), a 80 % of 1RM weight strength test with two different  bar sizes.</p><p><strong>Results:</strong> The results from the present investigation indicates a 21,1 % reduction of 80 % of 1 RM weight performance in repetitions executed in the bench press with the thicker diameter of the bar and a 66,2 % reduction in repetitions executed with a 80 % of 1 RM weight in the lying bench row with the thicker diameter of the bar. The size of the hand or the maximum grip strength does not influences the performance in the 80 % of 1 RM strength test.</p><p><strong>Conclusion: </strong>With support of the results from this present investigation the size of the bar diameter significant influences the performance in maximum repetitions executed in a set in strength training with free weights, in a rowing exercise the repetitions executed reduced with 66,2 % and in the bench press the reduction of executed repetitions were 21,1 % with the thicker diameter of the bar. The size of the hand do not influences the performance of maximal executed repetitions with the thicker bar diameter. Maximal grip strength has no influence of the performance according to the findings of this investigation.</p>