Introduction: Amyotrophic Lateral Sclerosis (ALS) is a fatal and progressive disease characterized by the deterioration of motor neurons within the body. This degeneration leads to bulbar dysfunction in the form of an impaired ability to communicate and swallow. Currently, bulbar dysfunction is treated via compensatory methods aimed at maximizing comfort and safety that include environmental adaptations, augmentative and assistive communication and gastrostomy tube placement to replace speech and oral feeding. The role of active intervention is controversial in this patient population and no investigations have examined the potential role lingual exercise might play in ALS bulbar management. The purpose of this study was to explore the impact of an eight week lingual resistance training program on lingual strength and lingual endurance, speech, swallowing, global disease progression and patient-reported outcomes in two individuals with ALS. Methods: Two individuals with ALS (El Escorial criteria) were enrolled across three different time points, each separated by eight weeks (Baseline 1, Baseline 2, Post-Treatment) with a delayed intervention design utilized to benchmark bulbar disease progression. At each evaluation, tongue strength, endurance, swallowing, speech and patient-reported outcomes were collected. Following Baseline 2, participants completed lingual resistance training five days a week for eight weeks (40 sessions). Outcome measures included maximum anterior isometric tongue pressure (MIP), maximum endurance hold time MHT), speech intelligibility, airway safety and patient-reported outcomes. Results: On average, MIPs decreased by 2% during the lead in period and increased by 13% across both participants. On average, MHT declined by 25% between baseline 1 and 2 and increased by 144% following lingual resistance training. No improvements were noted for speech intelligibility or airway safety during swallowing. Patient-perceptions of communicative effectiveness, swallowing impairment and quality of life remained relatively stable over the four-month period. Conclusion: Although no improvements were noted in lingual strength, improvements in lingual endurance hold times were noted in both participants. Further investigation is warranted to validate these preliminary findings in two cases of ALS.

Made available in DSpace on 2014-06-11T19:22:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-10Bitstream added on 2014-06-13T20:09:54Z : No. of bitstreams: 1 silva_cr_me_prud.pdf: 377360 bytes, checksum: 38ec03183b67a69d80d817be978919e6 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / São encontradas na literatura várias propostas de processamento do sinal eletromiográfico (EMG) com o objetivo de determinar índices aplicados à monitoração do processo de fadiga muscular localizada. Em comum, todos os índices são baseados na análise de algum parâmetro do sinal monitorado durante o exercício. A avaliação conjunta do comportamento das variáveis extraídas no domínio do tempo e da frequência do sinal eletromiográfico (EMG) não é uma tarefa trivial. Diante disso, os objetivos do estudo foram: i) identificar por meio do comportamento da frequência mediana (Fmed) e da raiz quadrada da média (RMS) do sinal EMG o momento de instalação da fadiga muscular localizada (MF); ii) determinar a reprodutibilidade entre dias da Fmed, RMS, e bandas de baixa (20-45 Hz), média (46-95 Hz) e alta (96-400 Hz) frequência do sinal EMG e iii) aplicar uma análise estatística multivariada nas variáveis extraídas do sinal EMG durante o início, MF e final do teste. Dezoito sujeitos saudáveis foram avaliados em dois dias diferentes, sendo registrados os sinais EMG dos músculos vasto medial (VM), reto femoral (RF) e vasto lateral (VL) durante contrações isométricas a 20% e 70% da contração voluntária isométrica máxima (CVIM), realizada até a exaustão. Por meio das análises realizadas no comportamento da Fmed e do RMS ao longo dos testes foi possível identificar o MF para o VM e VL em ambas as intensidades de carga... / Various proposals are found in the literature of electromiographic signal (EMG) processing with the purpose of determining indices applied to monitoring the localized muscle fatigue. In common, all indexes are based on analysis of some signal parameter monitored during the exercise. The joint evaluation of the behavior of variables extracted in the time and frequency domain of the EMG signal is not a trivial task. That said, the objectives of the study were: i) identify through the behavior of median frequency (MFreq) and the root mean square (RMS) of EMG signal in the moment of installation of localized muscle fatigue (MF); ii) determining the reproducibility between days of MFreq, RMS, and low bands (20-45 Hz), average (46-95 Hz) and high (96-400 Hz) frequency of EMG signal and iii) applying a multivariate statistical analysis in variables extracted from EMG signal during the beginning, MF and end of test. Eighteen healthy subjects were evaluated in two different days, being recorded the EMG muscle signals of vastus medialis (VM), rectus femoris (RF) and vastus lateralis (VL) during isometric contractions at 20% and 70% of maximum isometric voluntary contraction (MIVC), held until exhaustion. The analysis of MFreq and RMS behavior over the tests was possible to identify the MF for VM and VL in both load intensities. There were... (Complete abstract click electronic access below)

Orientador: Fábio Mícolis de Azevedo / Banca: Neri Alves / Banca: Fernando Henrique Magalhães / Resumo: São encontradas na literatura várias propostas de processamento do sinal eletromiográfico (EMG) com o objetivo de determinar índices aplicados à monitoração do processo de fadiga muscular localizada. Em comum, todos os índices são baseados na análise de algum parâmetro do sinal monitorado durante o exercício. A avaliação conjunta do comportamento das variáveis extraídas no domínio do tempo e da frequência do sinal eletromiográfico (EMG) não é uma tarefa trivial. Diante disso, os objetivos do estudo foram: i) identificar por meio do comportamento da frequência mediana (Fmed) e da raiz quadrada da média (RMS) do sinal EMG o momento de instalação da fadiga muscular localizada (MF); ii) determinar a reprodutibilidade entre dias da Fmed, RMS, e bandas de baixa (20-45 Hz), média (46-95 Hz) e alta (96-400 Hz) frequência do sinal EMG e iii) aplicar uma análise estatística multivariada nas variáveis extraídas do sinal EMG durante o início, MF e final do teste. Dezoito sujeitos saudáveis foram avaliados em dois dias diferentes, sendo registrados os sinais EMG dos músculos vasto medial (VM), reto femoral (RF) e vasto lateral (VL) durante contrações isométricas a 20% e 70% da contração voluntária isométrica máxima (CVIM), realizada até a exaustão. Por meio das análises realizadas no comportamento da Fmed e do RMS ao longo dos testes foi possível identificar o MF para o VM e VL em ambas as intensidades de carga... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Various proposals are found in the literature of electromiographic signal (EMG) processing with the purpose of determining indices applied to monitoring the localized muscle fatigue. In common, all indexes are based on analysis of some signal parameter monitored during the exercise. The joint evaluation of the behavior of variables extracted in the time and frequency domain of the EMG signal is not a trivial task. That said, the objectives of the study were: i) identify through the behavior of median frequency (MFreq) and the root mean square (RMS) of EMG signal in the moment of installation of localized muscle fatigue (MF); ii) determining the reproducibility between days of MFreq, RMS, and low bands (20-45 Hz), average (46-95 Hz) and high (96-400 Hz) frequency of EMG signal and iii) applying a multivariate statistical analysis in variables extracted from EMG signal during the beginning, MF and end of test. Eighteen healthy subjects were evaluated in two different days, being recorded the EMG muscle signals of vastus medialis (VM), rectus femoris (RF) and vastus lateralis (VL) during isometric contractions at 20% and 70% of maximum isometric voluntary contraction (MIVC), held until exhaustion. The analysis of MFreq and RMS behavior over the tests was possible to identify the MF for VM and VL in both load intensities. There were... (Complete abstract click electronic access below) / Mestre

Orientador: Mathias Vitti / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-07-27T15:26:22Z (GMT). No. of bitstreams: 1 Verri_EdsonDonizetti_M.pdf: 2091762 bytes, checksum: 8d7b8fd3fff4ba87b179b020ea70d390 (MD5) Previous issue date: 2001 / Resumo: O objetivo deste trabalho foi estudar a influência dos músculos bíceps do braço (cabeças curta e longa), braquiorradial e tríceps do braço (cabeças lateral, longa e medial), na atividade flexora do antebraço em diferentes posições articulares do ombro. Foram testadas contrações isométricas de flexão do antebraço semipronado a 90° com flexão de ombro a 90°, ombro neutro e ombro a 90° de abdução. Foram estudados dez voluntários jovens, do sexo feminino, com idades de 20 a 30 anos, e destros. Todos os voluntários eram não treinados e sem história de doença neuromuscular ou articular. Os registros foram obtidos, utilizando-se um eletromiógrafo computadorizado modelo MCS - V2 da LynxElectronicsLtda. Com módulo condicionador de sinais de 16 canais, e placa A/D modelo CAD 12/36 da Lynx Electronics Ltda. de 12 bites de resolução de faixa dinâmica, filtro do tipo Butterworth, de passa-baixa de 509 Hz, de passa-alta de 10,6 Hz, ganho 10 vezes e freqüências de amostragem de 1.000 Hz; software Aqdados versão 4,16 da Lynx Electronics Ltda. para apresentação dos sinais de diferentes canais simultaneamente e tratamento do sinal (valor de RMS, média, mínimo, máximo, e desvio padrão). Os sinais eletromiográficos foram captados por eletrodos de superflcie ativos diferenciais de superfície (Lynx Electronics Ltda). Os valores de RMS obtidos foram submetidos à análise estatística no programa GraphPad InStat, versão 3,01, Free Demo. Os dados foram testados quando a normalidade de distribuição pelo teste de Kolmogorov-Smirnov, e as comparações entre as médias de RMS foram feitas pelos testes ANOVA e Kruskal-Wallis. A correlação de Pearson foi usada para estabelecer uma relação entre a força de contração registrada e o sinal eletromiográfico de cada um dos músculos estudados. Através destes testes, os resultados mostraram que nos músculos estudados, não houve diferenças estatísticas para a atividade eletromiográfica e força de contração isométrica causada pela variação do posicionamento articular do ombro. Os valores de correlação de Pearson mostraram, para os flexores do antebraço, maior correlação no posicionamento neutro do ombro, enquanto o valor médio de RMS do músculo tríceps foi mais correlacionado com a força registrada com a articulação do ombro posicionada em 90° de abdução. O músculo tríceps do braço age em cocontração para proteger e estabilizar as articulações do cotovelo e do ombro durante os registros da contração isométrica de flexão do antebraço em esforço máximo. A variação dos comprimentos dos músculos biarticulares não foi suficiente para alterar os níveis de força e do sinal eletromiográfico, nas contrações isométricas de flexão do antebraço, combinadas com a semipronação e as variações dos posicionamentos articulares do ombro, sugerindo uma maior contribuição destinada à estabilização das articulações do cotovelo e do ombro / Abstract: The purpose of this study was to analyze the influence of biceps raquialis, braquiorradial, and triceps braquialis on the flexon activity at different positions of the shoulder joint. It was observed the isometric semipronate elbow flexion contractions with anatomical position of the shoulder, 90° shoulder flexion and 90s houder abduction. Ten healthy female young volunteers, right-handed and no-trained were evaluate. The registers of electromyographic and force output were acquired by a 12 bit A/D converter board with a sample frequency of 1000 Hz, Butterworth filter with low-pass of 509 Hz and high-pass of 10,6 HZ (model CAD 12/36 of Lynx Electronics Ltda.), and gain of 1000 times. The Aqdados software 4.16 version (Lynx Electronics Ltda) was used to present and analyze the different signals simultaneously (RMS, mean, standard deviation, maximum, minimum values). The electromyographic signals were detected with a differential bipolar surface electrode (Lynx Electronics Ltda.) over the musc1ebelly placed between a motor point and the tendon insertion. The force output was measured with a load cell.In all trials, the load celI was positioned with it alignrnent perpendicular to the limb. The RMS and force mean values were statisticalIy evaluated by the GraphPad InStar, 3,01 Free Demo version. The data were tested with Kolmogorov-Smimov normal distribution test, and the mean RMS and force comparison were performed by ANOVA and Kruskal-Wallis tests. The Pearson correlation was used to establish a relationship between RMS and force values for each of the studied musc1es. The results showed that no statistical differences were found to electromyographic activity and force output in the isometric elbow flexion contractions caused by the variation of the shoulder position. The Pearson correlation values showed that greater correlation for the flexor musc1esoccurred at 90° of the shoulder abduction, while the greater correlation for the triceps braquialis occurred at anatomical shoulder position. The triceps braquialis musc1e act in cocontraction to protect and stabilize the shoulder and elbow joints during the isometric elbow flexion contractions in maximum effort. The length variation of the biarticular musc1e by the shoulder variation in the isometric elbow flexion contractions combined with semipronation was not enough to alter the force levels of the force output and electromyographic signals. This suggest that the greater contribution of the contraction of the studied musc1eswas destined to stabilization of the shoulder and elbow joints / Mestrado / Mestre em Biologia e Patologia Buco-Dental

Orientador: Maria Claudia Gonçalves de Oliveira Fusaro / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Aplicadas / Made available in DSpace on 2018-08-25T13:04:54Z (GMT). No. of bitstreams: 1 Santos_DiogoFranciscodaSilvados_M.pdf: 1159978 bytes, checksum: d14c7c199ca0e75686645ae3ca6a131c (MD5) Previous issue date: 2014 / Resumo: De todas as dores que acometem o ser humano ao longo da sua existência, a dor muscular, especialmente a induzida por contração isométrica sustentada, é uma das mais prevalentes e possui um importante impacto sócio-econômico. Entretanto, apesar da sua relevância clínica, os mecanismos moleculares envolvidos no desenvolvimento da dor muscular induzida pela contração isométrica sustentada são pouco conhecidos. Isto se deve, principalmente, à ausência de um modelo experimental mais realístico e com bom grau de predição do controle farmacológico desta dor. Portanto, o objetivo deste trabalho foi desenvolver um novo modelo de hiperalgesia muscular induzido por contração isométrica sustentada em ratos. A contração isométrica sustentada foi realizada por estimulações elétricas aplicadas diretamente no ventre do músculo gastrocnêmio de ratos wistar e os parâmetros foram de 19 milissegundos de duração de pulso, frequência em 50 Hertz, intensidade de 1,6 Volts (V) por um período de 1 hora. A hiperalgesia muscular mecânica foi avaliada com o método Randall Selitto nos tempos de meia hora até 48 horas após o término da contração isométrica sustentada. A contração isométrica sustentada, obedecendo o parâmetros supracitados, induziu hiperalgesia muscular mecânica por 1 hora, regredindo com valores próximos ao basal 2 horas após o término da contração. As respostas com 1,6V por 1 hora, foram significativamente maiores do que as induzidas por estimulações de 1,6V por 15 e 30 minutos; 0,5 e 1,0V por 1h ou sham. Demonstramos ainda que a hiperalgesia muscular mecânica induzida pela contração isométrica sustentada foi bloqueada pela dexametasona, evidenciando o caráter inflamatório desse novo modelo, respaldado pela presença de células inflamatórias no tecido muscular, confirmadas pela análise histológica. Juntos, estes dados sugerem que esse novo modelo de hiperalgesia muscular se aproxima de uma condição mais próxima da real encontrada nas dores musculares decorrentes das atividades diárias, além de possuir um grande potencial científico para os estudos dos mecanismos fisiopatológicos envolvidos na dor muscular relacionada à contração isométrica sustentada / Abstract: Among the types of pain that affect people throughout their lives, muscle pain, specially the one induced by sustained isometric contraction, is one of the most prevalent and has an important socio-economic impact. However, despite their clinical relevance, the molecular mechanisms involved in the development of muscle pain induced by sustained isometric contraction are unknown. This is mainly due to the absence of a more realistic experimental model that has a good degree of prediction of pharmacological control of pain. Therefore, the aim of this study was to develop a new model of muscle hyperalgesia induced by sustained isometric contraction in Wistar rats. The sustained isometric contraction was performed by the electrical stimulation directly to the belly of the gastrocnemius muscle of rats and the parameters were 19 millisecond of pulse duration, frequency of 50Hz, and intensity of 1.6 volts (V) for a period of 1 hour. Randall Selitto method was used to measure muscular hyperalgesia 30 minutes until 48 hours after the finish of sustained isometric contraction. This protocol induced mechanical muscle hyperalgesia for one hour and, after two hours, the responses were similar to the baseline. These responses were significantly higher than those induced by stimulation 1.6V for 15 and 30 minutes, 0.5 and 1.0 V for 1h or sham. We also demonstrated that the mechanical muscle hyperalgesia induced by sustained isometric contraction was blocked by dexamethasone, indicating the inflammatory nature of this new model, supported by the presence of inflammatory cells in muscle tissue, confirmed by histological analysis. Together, these data suggest that this new model of muscle hyperalgesia approaching a condition closest to the actual found in muscle pain resulting from daily activities, besides having a great scientific potential for the study of pathophysiological mechanisms involved in muscle pain related to contraction sustained isometric / Mestrado / Metabolismo e Biologia Molecular / Mestre em Ciências da Nutrição e do Esporte e Metabolismo

M.Tech. (Chiropractic) / Aim: The aim of this study was to determine if a chiropractic adjustment had an effect on muscle strength. The study then aimed to compare the effects a resistance training protocol, to a chiropractic adjustment, to a combination of these two treatments on the neck strength of individuals with cervical facet syndrome. Method: This study consisted of three groups of 10 participants each. The participants were grouped by stratified sampling to balance the groups in terms of age and gender. The participants ranged in age from 22 to 28 years. There were 18 male and 12 female participants. Participants were examined and accepted into the trail according to inclusion and exclusion criteria. Treatment was allocated according to groupings. Group 1 received a resistance training protocol, group 2 received chiropractic adjustment only and group 3 received a combination of both treatments. Procedure: Treatment consisted of 6 treatment sessions and a 7th follow up session, over a three week period. Participants in group 1 and 3 were instructed to perform the demonstrated resistance training protocol 3 times a week for 3 weeks. Participants in group 2 and 3 received chiropractic adjustments to hypomobile cervical spine segments, twice a week for three weeks. Cervical range of motion (CROM) was mesured using a CROM device and strength readings were measured using a hand held isometric dynamometer. Measurements were recorded on the 1st, 4th and 7th visits. All participants were required to fill in a Vernon-Mior Neck Disability Index (NDI) on the 1st and 7th visits. The data collected was analysed by a statistician. Results: Analysis of the Vernon-Mior NDI intra-group results showed that all three groups were effective in reducing cervical pain and disability. There was no statistical difference in improvement between the groups. CROM results indicated that all three groups successfully increased cervical range of motion. The combination group had the greatestimprovement, followed by the adjustment group and lastly the resistance training group. The combination group showed statistical improvements in all ranges of motion at visit 4 while this was only achieved by the resistance training group at visit 7. In the adjustment group statistical changes in flexion, extension and lateral flexion were only noted at visit 7, however in rotation, statistical improvements were noted at visit 4. Isometric dynamometer analysis showed that all 3 groups did show a statistically significant increase in cervical muscle strength. The combination group provided the greatest gains, followed by the adjustment group. The smallest gains were seen in the resistance training group. Statistical changes in the resistance training group were only measured at visit 7, while in the combination and adjustment group, these changes were noted by visit 4. Conclusion: Chiropractic adjustment was effective in increasing neck strength. Of the 3 groups, the combination treatment proved to be the most effective method of improving neck strength in individuals with cervical facet syndrome. Of the two individual treatments, chiropractic adjustment was more effective in terms of both strength gains and time taken to achieve these results, than the resistance training protocol.

Current knowledge indicates that nonthermal muscle metaboreflex activity plays a critical role in the modulation of skin vasodilation and sweating. However, the mechanisms of control have primarily been studied during isometric handgrip exercise in which muscle metaboreceptor activation is induced by a brief post-exercise ischemia of the upper limb. While the reflex increase in mean arterial pressure associated with this period of ischemia is consistent with the activation of muscle metaboreceptors, the change in baroreflex activity may in itself modulate the response. Thus, we sought to understand how these nonthermal stimuli interact in modulating the control of skin perfusion and sweating under conditions of elevated hyperthermia. Furthermore, we examined the mechanisms responsible for the maintenance of arterial blood pressure under varying levels of heat stress during isometric handgrip exercise. Our study findings indicate that the parallel activation of muscle metaboreceptors and baroreceptors during post-exercise ischemia causes divergent influences on the control of skin blood flow and sweating; and these nonthermal stimuli are dependent on the level of hyperthermia. Moreover, we report that heat stress reduces the increase in arterial blood pressure during isometric handgrip exercise and this attenuation is attributed to a blunted increase in peripheral resistance, since cardiac output increased to similar levels for all heat stress conditions. These results provide important insight and understanding into the role of muscle metabo- and baroreflex activity on the control of skin blood flow and sweating; along with further knowledge into the cardiovascular mechanisms responsible for the regulation of arterial blood pressure during hyperthermia.

Orientadores: Maria Cláudia Gonçalves de Oliveira Fusaro, Andrea Maculano Esteves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Aplicadas / Made available in DSpace on 2018-08-27T04:11:06Z (GMT). No. of bitstreams: 1 Jorge_CarolinaOcanha_M.pdf: 1325403 bytes, checksum: 6635807ae28ce8dbb49ec5d1bcc74a75 (MD5) Previous issue date: 2015 / Resumo: A dor musculoesquelética é um importante problema de saúde mundial. Dentre todos os tipos de dor, àquela induzida pela contração isométrica sustentada está relacionada com os movimentos corporais nas atividades da vida diárias e apresenta um alto impacto socioeconômico. Apesar da sua relevância clínica, os mecanismos moleculares envolvidos no desenvolvimento da dor muscular induzida pela contração isométrica sustentada são pouco conhecidos. Portanto, o objetivo deste estudo foi avaliar o envolvimento dos receptores TRPV1 e TRPA1 na hiperalgesia muscular mecânica induzida pela contração isométrica sustentada no músculo gastrocnêmio de ratos machos, da linhagem wistar. O antagonista seletivo do receptor TRPV1, AMG9810, reduziu significativamente a hiperalgesia muscular mecânica induzida pela contração isométrica sustentada quando administrado no músculo gastrocnêmio ipsilateral, mas não no contralateral. A administração intratecal de AMG9810 apresentou a mesma resposta. Similar ao TRPV1, a administração intramuscular e intratecal do antagonista seletivo do receptor TRPA1, HC030031, reduziu significativamente a hiperalgesia muscular induzida pela contração isométrica sustentada. No entanto, não foi observado modificação da expressão proteica dos receptores TRPV1 e TRPA1 no tecido muscular após a contração isométrica sustentada. Os dados sugerem que os receptores TRPV1 e TRPA1 expressos no músculo gastrocnêmio e corno dorsal da medula espinhal estão envolvidos na hiperalgesia muscular mecânica induzida pela contração isométrica sustentada em ratos. Sugerimos, portanto, que os receptores TRPV1 e TRPA1 co-expressos nas fibras aferentes primárias trabalhem juntos para ativar os nociceptores das fibras aferentes durante a contração isométrica sustentada. Além disso, nós sugerimos que os receptores TRPV1 e TRPA1 sejam potenciais alvos para o controle da dor muscular inflamatória / Abstract: Musculoskeletal pain is an important health issue in the world. Among the kinds of muscle pain, the one induced by sustained isometric contraction is associated with body movements of the daily life and has a high socio-economic impact. Despite its clinical relevance, the molecular mechanisms involved in the development of muscle pain induced by sustained isometric contraction are poorly understood. Therefore, the aim of this study was to evaluate the involvement of TRPV1 and TRPA1 receptors in the mechanical muscle hyperalgesia induced by sustained isometric contraction of the gastrocnemius muscle of rats. The selective TRPV1 receptor antagonist AMG 9810 reduced the mechanical muscle hyperalgesia induced by sustained isometric contraction when administered in the ipsilateral but not in the contralateral gastrocnemius muscle. Also, the intratecal administration of AMG9810 reduced the same response. Similar to TRPV1, intramuscular and intrathecal administration of selective TRPA1 receptor antagonist HC030031 reduced the mechanical muscle hyperalgesia induced by sustained isometric contraction. Finally, the sustained isometric contraction did not modify the protein expression of TRPV1 and TRPA1 receptors in muscle tissue. We concluded that TRPV1 and TRPA1 receptors expressed in gastrocnemius muscle and spinal cord dorsal horn are involved with the mechanical muscle hyperalgesia induced by sustained isometric contraction in rats. We suggest that TRPV1 and TRPA1 receptors co-expressed in primary afferent fibers work together to activate nociceptive afferent fibers during sustained isometric contraction. Also, we suggest that TRPV1 and TRPA1 receptors are potential target to control inflammatory muscle pain / Mestrado / Biodinâmica do Movimento Humano e Esporte / Mestra em Ciências da Nutrição e do Esporte e Metabolismo

Abstract available in the 10th Annual Coaches and Sport Science College .

Many clinicians believe exercise associated muscle cramps (EAMC) occur because of dehydration and electrolyte losses. Experimental research supporting this theory is lacking. Mild hypohydration (3% body mass loss) does not alter cramp threshold frequency (TF), a measure of cramp susceptibility, when fatigue and exercise intensity are controlled. No experimental research has examined TF following significant (3-5% body mass loss) or serious hypohydration (>5% body mass loss). TF and blood variables of ten subjects were measured pre-post exercise. Subjects exercised in an environmental heat chamber alternating between upper arm ergometry and non-dominant leg cycling every 15 minutes until they lost 5% of their body mass or were too exhausted to continue. Significant (n=5) or serious hypohydration (n=5) did not alter cramp TF, cramp intensity, or cramp EMG amplitude. Significant and serious hypohydration with moderate electrolyte losses does not alter cramp susceptibility when fatigue and exercise intensity are controlled.