Changes in interstitial noradrenaline, trapezius muscle activity and oxygen saturation during low-load work and recovery
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Both physical as well as mental demands result in an increased activity in the sympathetic nervous system (SNS) with changes in blood-pressure and heart-rate. Through local release of catecholamines, e.g. noradrenaline (NAd) SNS exerts various actions at the muscle level. The aims of this study were to investigate the effects of low-load repetitive work alone and in combination with mental demands on local muscle interstitial noradrenaline concentration [NAd]i, muscle activity and oxygenation, assessed with microdialysis, surface electromyography, and near-infrared spectroscopy, respectively. Healthy females (n = 15) were exposed to (1) 30 min repetitive work (RW) and (2) 30 min repetitive work with superimposed mental load (RWML) on two different occasions. Muscle [NAd]i and muscle activity increased significantly in response to RW, but did not increase further during RWML. For RW, [NAd]i was found to be inversely correlated to muscle activity. Oxygenation decreased significantly during work, independently of occasion. Our findings indicate that low-load work causes significantly increased trapezius muscle [NAd]i in healthy females, and short periods of superimposed mental load do not add to this increase and further, that both muscle activity and oxygenation were unaffected by the superimposed mental load.
KeywordsMicrodialysis Near-infrared spectroscopy Electromyography Mental load Subjective ratings Healthy females
Special thanks are due to Margaretha Marklund, Per Gandal and Göran Sandström for qualified technical assistance, Ivana Kalecic for help with improving the HPLC-analysis, Fredrik Hellström for reading and commenting the manuscript and lastly to Kjell Karp for providing laboratory resources. The financial support of the Swedish Agency for Innovation Systems, VINNOVA (project no. 510240) is also gratefully acknowledged.
- Bernard B (1997) Musculoskeletal disorders and workplace factors: a critical review of epidemiologic evidence for work related musculoskeletal disorders of the neck, upper extremity, and low back, 2nd edn. US Department of Health and Human Services, NIOSH, CincinnatiGoogle Scholar
- Bongers PM, Ijmker S, van den Heuvel S et al (2006) Epidemiology of work related neck and upper limb problems: psychosocial and personal risk factors (Part I) and effective interventions from a bio behavioural perspective (Part II). J Occup Rehabil 16:279–302. doi: 10.1007/s10926-006-9044-1 PubMedCrossRefGoogle Scholar
- Bosch T, de Looze MP, Kingma I, Visser B, van Dieën JH (2008) Electromyographical manifestations of muscle fatigue during different levels of simulated light manual assembly work. J Electromyogr Kinesiol. doi: 10.1016/j.jelekin
- Bowman WC (1980) Effects of adrenergic activators and inhibitors on skeletal muscles. In: Szekeres L (ed) Adrenergic activators and inhibitors. Handbook of experimental pharmacology, vol 54/2. Springer, New York, pp 47–128Google Scholar
- Chaurasia CS (1999) In vivo microdialysis sampling: theory and applications. Biomed Chromatogr 13:317–332. doi: 10.1002/(SICI)1099-0801(199908)13:5<317::AID-BMC891>3.0.CO;2-I PubMedCrossRefGoogle Scholar
- Flodgren GM, Hellström FB, Fahlström M et al (2006) Effects of 30 versus 60 min of low-load work on intramuscular lactate, pyruvate, glutamate, prostaglandin E(2) and oxygenation in the trapezius muscle of healthy females. Eur J Appl Physiol 97:557–565. doi: 10.1007/s00421-006-0216-7 PubMedCrossRefGoogle Scholar
- Holm S (1979) A simple sequential rejective multiple test procedure. Scand J Stat 6:65–70Google Scholar
- Johansson H, Arendt-Nilsson L, Bergenheim M (2003) An integrated model for chronic work related myalgia “Brussels model”. In: Johansson H, Windhorst U, Djupsjöbacka M, Passatore M et al (eds) Chronic work-related myalgia. Neuromuscular mechanisms behind work-related chronic muscle pain syndromes. Gävle University Press, GävleGoogle Scholar
- Rosendal L, Blangsted AK, Kristiansen J, Søgaard K, Langberg H, Sjøgaard G, Kjaer M (2004a) Interstitial muscle lactate, pyruvate and potassium dynamics in the trapezius muscle during repetitive low-force arm movements, measured with microdialysis. Acta Physiol Scand 182(4):379–388. doi: 10.1111/j.1365-201X.2004.01356.x PubMedCrossRefGoogle Scholar
- Rosendal L, Larsson B, Kristiansen J, Peolsson M, Søgaard K, Kjaer M, Sørensen J, Gerdle B (2004b) Increase in muscle nociceptive substances and anaerobic metabolism in patients with trapezius myalgia: microdialysis in rest and during exercise. Pain 112(3):324–334. doi: 10.1016/j.pain.2004.09.017 PubMedCrossRefGoogle Scholar
- Sjøgaard G, Søgaard K (1998) Muscle injury in repetitive motion disorders. Clin Orthop Relat Res (351):21–31Google Scholar