Force Variability and Musculoskeletal Pain in Blue-Collar Workers

  • Kristoffer Larsen NorheimEmail author
  • Jakob Hjort Bønløkke
  • Øyvind Omland
  • Afshin Samani
  • Pascal Madeleine
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 826)


Blue-collar workers with physically demanding occupations have a high prevalence of musculoskeletal disorders accompanied by pain. Previous research has suggested that reduced motor variability may increase the risk of developing musculoskeletal disorders. Here we present preliminary data from an ongoing cross-sectional examination of physical performance in elderly manual workers. This paper includes data from 20 male workers (age 52–70 years). Handgrip force variability was measured using a digital hand dynamometer during an endurance trial where the workers exerted 30% of their maximal isometric contraction force until task failure. Absolute variability (standard deviation), relative variability (coefficient of variation), and the complexity of the force signal (sample entropy) were computed. The workers were dichotomized into two groups: no to mild pain/discomfort (No pain) and moderate to severe pain/discomfort (Pain) to investigate the effects of musculoskeletal pain on force variability. This dichotomy was done based on the rating of pain/discomfort within the last seven days, where workers reporting ≥3 score in the upper extremities were allocated to the pain group (Pain, n = 9, No pain, n = 11). No significant between-group differences in force variability during the endurance trial were found. Both absolute and relative variability increased significantly over time. These preliminary data do not support a difference in force variability between blue-collar workers with or without musculoskeletal pain or discomfort in the upper extremities.


Handgrip strength Endurance Motor control Discomfort 



The project is funded by Arbejdsmiljøforskningsfonden (project number 20140072843). Also, the authors would like to thank the rest of the ALFA-group, which includes Kirsten Fonager, Henrik Bøggild, Johan Hviid Andersen, and Claus Dalsgaard Hansen.


  1. 1.
    Larsen M, Pedersen PJ (2017) Labour force activity after 65: what explain recent trends in Denmark, Germany and Sweden? J Labour Mark Res 50:15–27. Scholar
  2. 2.
    Tuomi K, Huuhtanen P, Nykyri E, Ilmarinen J (2001) Promotion of work ability, the quality of work and retirement. Occup Med Oxf Engl 51:318–324CrossRefGoogle Scholar
  3. 3.
    Caban-Martinez AJ, Lowe KA, Herrick R, Kenwood C, Gagne JJ, Becker JF, Schneider SP, Dennerlein JT, Sorensen G (2014) Construction workers working in musculoskeletal pain and engaging in leisure-time physical activity: findings from a mixed-methods pilot study. Am J Ind Med 57:819–825. Scholar
  4. 4.
    de Zwart BC, Broersen JP, Frings-Dresen MH, van Dijk FJ (1997) Repeated survey on changes in musculoskeletal complaints relative to age and work demands. Occup Environ Med 54:793–799CrossRefGoogle Scholar
  5. 5.
    Eurofound (2017) Sixth European working conditions survey – overview report (2017 update). Publications Office of the European Union, LuxembourgGoogle Scholar
  6. 6.
    Madeleine P, Mathiassen SE, Arendt-Nielsen L (2008) Changes in the degree of motor variability associated with experimental and chronic neck-shoulder pain during a standardised repetitive arm movement. Exp Brain Res 185:689–698. Scholar
  7. 7.
    Søndergaard KHE, Olesen CG, Søndergaard EK, de Zee M, Madeleine P (2010) The variability and complexity of sitting postural control are associated with discomfort. J Biomech 43:1997–2001. Scholar
  8. 8.
    Norheim KL, Bønløkke JH, Samani A, Omland Ø, Madeleine P (2017) The effect of aging on physical performance among elderly manual workers: protocol of a cross-sectional study. JMIR Res Protoc 6:e226. Scholar
  9. 9.
    Kuorinka I, Jonsson B, Kilbom A, Vinterberg H, Biering-Sørensen F, Andersson G, Jørgensen K (1987) Standardised Nordic questionnaires for the analysis of musculoskeletal symptoms. Appl Ergon 18:233–237CrossRefGoogle Scholar
  10. 10.
    Boonstra AM, Stewart RE, Köke AJA, Oosterwijk RFA, Swaan JL, Schreurs KMG, Schiphorst Preuper HR (2016) Cut-off points for mild, moderate, and severe pain on the numeric rating scale for pain in patients with chronic musculoskeletal pain: variability and influence of sex and catastrophizing. Front Psychol 7:1466. Scholar
  11. 11.
    Boonstra AM, Schiphorst Preuper HR, Balk GA, Stewart RE (2014) Cut-off points for mild, moderate, and severe pain on the visual analogue scale for pain in patients with chronic musculoskeletal pain. Pain 155:2545–2550. Scholar
  12. 12.
    Svendsen JH, Madeleine P (2010) Amount and structure of force variability during short, ramp and sustained contractions in males and females. Hum Mov Sci 29:35–47. Scholar
  13. 13.
    Srinivasan D, Mathiassen SE (2012) Motor variability in occupational health and performance. Clin Biomech 27:979–993. Scholar
  14. 14.
    Skurvydas A, Brazaitis M, Kamandulis S, Sipaviciene S (2010) Muscle damaging exercise affects isometric force fluctuation as well as intraindividual variability of cognitive function. J Mot Behav 42:179–186. Scholar
  15. 15.
    Madeleine P (2010) On functional motor adaptations: from the quantification of motor strategies to the prevention of musculoskeletal disorders in the neck-shoulder region. Acta Physiol Oxf Engl 199(Suppl 679):1–46. Scholar
  16. 16.
    Justice JN, Mani D, Pierpoint LA, Enoka RM (2014) Fatigability of the dorsiflexors and associations among multiple domains of motor function in young and old adults. Exp Gerontol 55:92–101. Scholar
  17. 17.
    Hunter SK, Ryan DL, Ortega JD, Enoka RM (2002) Task differences with the same load torque alter the endurance time of submaximal fatiguing contractions in humans. J Neurophysiol 88:3087–3096. Scholar
  18. 18.
    Mista CA, Monterde S, Inglés M, Salvat I, Graven-Nielsen T (2018) Reorganised force control in elbow pain patients during isometric wrist extension. Clin J Pain. Scholar
  19. 19.
    Salomoni SE, Graven-Nielsen T (2012) Experimental muscle pain increases normalized variability of multidirectional forces during isometric contractions. Eur J Appl Physiol 112:3607–3617. Scholar
  20. 20.
    Holtermann A, Søgaard K, Christensen H, Dahl B, Blangsted AK (2008) The influence of biofeedback training on trapezius activity and rest during occupational computer work: a randomized controlled trial. Eur J Appl Physiol 104:983–989. Scholar
  21. 21.
    Samani A, Holtermann A, Søgaard K, Madeleine P (2010) Active biofeedback changes the spatial distribution of upper trapezius muscle activity during computer work. Eur J Appl Physiol 110:415–423. Scholar
  22. 22.
    Enoka RM, Duchateau J (2016) Translating fatigue to human performance. Med Sci Sports Exerc 48:2228–2238. Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Sports Sciences, Department of Health Science and Technology, Faculty of MedicineAalborg UniversityAalborgDenmark
  2. 2.Clinic of Occupational MedicineAalborg University HospitalAalborgDenmark

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