Objective: To determine the effects of intermittent task parameters on muscle fatigue and endurance time during static shoulder abductions, with a long-term goal of establishing relationships between intermittent task parameters and short-term performance. Background: Effects of intermittent work on endurance and fatigue development have been reported, and certain combinations of contraction levels and duty cycles have been proposed as design guidelines. These findings, however, were not derived from systematic manipulations of the task parameters. Method: Prolonged (1-hr maximum) intermittent shoulder abductions were performed at different combinations of contraction level (12% or 28% of muscle strength), duty cycle (.25 or .75), and cycle time (34 or 166 s). Fatigue was measured based on reductions in muscle strength and indirectly by changes in ratings of discomfort, electro-myographic (EMG) amplitude, and EMG spectral distribution. Results: Contraction level and duty cycle significantly affected endurance time and muscle fatigue, and interactive effects between these parameters were observed for some of the measures. Significant effects of cycle time were found only for EMG spectral measures. Conclusion: Endurance time and local fatigue were dependent on the comprehensive effects of the different task parameters. Application: Design changes to reduce the occurrence of localized fatigue during intermittent work need to take into account all the task parameters simultaneously.
Get full access to this article
View all access options for this article.
References
1.
Åhsberg, E., & Gamberale, F. (1998). Perceived fatigue during physical work: An experimental evaluation of fatigue inventory. International Journal of Industrial Ergonomic, 21, 117–131.
2.
Arendt-Nielsen, L., & Mills, K. R. (1988). Muscle fiber conduction velocity, mean power frequency, mean EMG voltage and force during submaximal fatiguing contractions of human quadriceps. European Journal of Applied Physiology, 58, 20–25.
3.
Arendt-Nielsen, L., Mills, K. R., & Forster, A. (1989). Changes in muscle fiber conduction velocity, mean power frequency, and mean EMG voltage during prolonged submaximal contractions. Muscle and Nerve, 12, 493–497.
4.
Baidya, K. N., & Stevenson, M. G. (1988). Local muscle fatigue in repetitive work. Ergonomics, 31, 227–239.
5.
Bergamasco, R., Girola, C., & Colombini, D. (1998). Guidelines for designing jobs featuring repetitive tasks. Ergonomics, 41, 1364–1383.
6.
Bigland-Ritchie, B., Furbush, F., & Woods, J. J. (1986). Fatigue of intermittent submaximal voluntary contractions: Central and peripheral factors. Journal of Applied Physiology, 61, 421–429.
7.
Bigland-Ritchie, B., Rice, C. L., Garland, S. J., & Walsh, M. L. (1995). Task-dependent factors in fatigue of human voluntary contractions. In S. C. Gandevia, A. J. McComas, R. M. Enoka, D. G. Stuart, & C. K. Thomas (Eds.), Advances in experimental medicine and biology (pp. 361–380). New York: Plenum Press.
8.
Bigland-Ritchie, B., & Woods, J. J. (1984). Changes in muscle contractile properties and neural control during human muscular fatigue. Muscle and Nerve, 7, 691–699.
9.
Björkstén, M., & Jonsson, B. (1977). Endurance limit of force in long-term intermittent static contraction. Scandinavian Journal of Work, Environment and Health, 3, 23–27.
10.
Borg, G. (1990). Psychophysical scaling with applications in physical work and the perception of exertion. Scandinavian Journal of Work, Environment, and Health, 16(Suppl. 1), 55–58.
11.
Byström, S., & Fransson-Hall, C. (1994). Acceptability of intermittent handgrip contractions based on physiological response. Human Factors, 36, 158–171.
12.
Byström, S. E. G., & Kilbom, Å. (1990). Physiological response in the forearm during and after isometric intermittent handgrip. European Journal of Applied Physiology, 66, 457–466.
13.
Byström, S. E. G., Mathiassen, S. E., & Fransson-Hall, C. (1991). Physiological effects of micropauses in isometric handgrip exercise. European Journal of Applied Physiology, 63, 405–411.
14.
Clarke, D. H., & Gentry, D. H. (1971). Individual differences in hand-grip and elbow flexion fatigue. Journal of Motor Behavior, 3, 225–234.
15.
Corcos, D. M., Jiang, H.-Y., Wilding, J., & Gottlieb, G. L. (2002). Fatigue induced changes in phasic muscle activation patterns for fast elbow flexion movements. Experimental Brain Research, 142, 1–12.
16.
Cram, J. R., Kasman, G. S., & Holtz, J. (1998). Introduction to surface electromyography. Gaithersburg, MD: Aspen.
17.
De Luca, C. J. (1997). The use of surface electromyography in bio-mechanics. Journal of Applied Biomechanics, 13, 135–163.
18.
Dieën, J. H. van, & Heijblom, P. (1996). Reproducibility of isometric trunk extension torque, trunk extensor endurance, and related electromyographic parameters in the context of their clinical applicability. Journal of Orthopaedic Research, 14, 139–143.
19.
Dieën, J. H. van, Oude Vrielink, H. H. E., & Toussaint, H. M. (1993). An investigation into the relevance of the pattern of temporal activation with respect to erector spinae muscle endurance. European Journal of Applied Physiology, 66, 70–75.
20.
Dul, J., Douwes, M., & Smitt, P. (1994). Ergonomic guidelines for the prevention of discomfort of static postures based on endurance data. Ergonomics, 37, 807–815.
21.
Gamet, D., Dûchene, J., Garapon-Bar, C., & Goubel, F. (1993). Surface electromyogram power spectrum in human quadriceps muscle during incremental exercise. Journal of Applied Physiology, 74, 2704–2710.
22.
Gerdle, B., Larsson, B., & Karlsson, S. (2000). Criterion validation of surface EMG variables as fatigue indicators using peak torque: A study of repetitive maximum isokinetic knee extension. Journal of Electromyography and Kinesiology, 10, 225–232.
23.
Grant, K. A., Habes, D. J., & Putz-Anderson, V. (1994). Psychophysical and EMG correlates of force exertion in manual work. International Journal of Industrial Ergonomics, 13, 31–39.
24.
Hagberg, M. (1981a). Electromyographic signs of shoulder muscular fatigue in two elevated arm positions. American Journal of Physical Medicine, 60, 111–121.
25.
Hagberg, M. (1981b). Muscular endurance and surface electro-myogram in isometric and dynamic exercise. Journal of Applied Physiology, 51, 1–7.
26.
Hermens, H. J., Freriks, B., Merletti, R., Stegeman, D., Blok, J., Rau, G., et al. (1999). European recommendations for surface electro-myography. Enschede, Netherlands: Roessingh Research and Development.
27.
Hunter, S. K, & Enoka, R. M. (2001). Sex differences in the fatigability of arm muscles depends on absolute force during isometric contractions. Journal of Applied Physiology, 91, 2686–2694.
28.
Hunter, S. K., Ryan, D. L., Ortega, J. D., & Enoka, R. M. (2002). Task differences with the same load torque alter the endurance time of submaximal fatiguing contractions in humans. Journal of Neuro-physiology, 88, 3087–3096.
29.
Jensen, B. R., Laursen, B., & Sjogaard, G. (2000). Aspects of shoulder function in relation to exposure demands and fatigue—A mini review. Clinical Biomechanics, 15, S17–S20.
30.
Jørgensen, K., Fallentin, N., Krough-Lund, C., & Jensen, B. (1988). Electromyography and fatigue during prolonged, low-level static contractions. European Journal of Applied Physiology, 57, 316–321.
31.
Keppel, G. (1991). Design and analysis: A researcher–s handbook. Upper Saddle River, NJ: Prentice-Hall.
32.
Lewis, S. F., & Fulco, C. S. (1998). A new approach to studying muscle fatigue and factors affecting performance during dynamic exercise in humans. Exercise and Sport Sciences Reviews, 26, 91–115.
33.
Lindström, L., Kadefors, R., & Petersén, I. (1977). An electromyo-graphic index for localized muscle fatigue. Journal of Applied Physiology, 43, 750–754.
34.
Luttmann, A., Jager, M., & Laurig, W. (2000). Electromyographical indication of muscular fatigue in occupational field studies. International Journal of Industrial Ergonomics, 25, 645–660.
35.
Mathiassen, S. E., & Winkel, J. (1992). Can occupational guidelines for work-rest schedules be based on endurance time data?Ergonomics, 35, 253–259.
36.
Merletti, R., & Lo Conte, L. R. (1997). Surface EMG signal processing during isometric contractions. Journal of Electromyography and Kinesiology, 7, 241–250.
37.
Merletti, R., Lo Conte, L. R., & Orizio, C. (1991). Indices of muscle fatigue. Journal of Electromyography and Kinesiology, 1, 20–33.
38.
Monod, H., & Scherrer, J. (1965). The work capacity of a synergic muscular group. Ergonomics, 8, 329–338.
39.
Moore, A. E. (2000). Effect of cycle time and duty cycle on muscle activity during a repetitive manual task. In Proceedings of the XIVth Triennial Congress of the International Ergonomics Association and 44th Annual Meeting of the Human Factors and Ergonomics Society (pp. 5.461–5.464). Santa Monica, CA: Human Factors and Ergonomics Society.
40.
Mundale, M. O. (1970). The relationship of intermittent isometric exercise to fatigue of hand grip. Archives of Physical Medicine and Rehabilitation, 51, 532–539.
41.
Neter, J., Kutner, M. H., Nachtsheim, C. J., & Wasserman, W. (1996). Applied linear statistical models. Chicago: Irwin.
42.
Nussbaum, M. A. (2001). Static and dynamic myoelectric measures of shoulder muscle fatigue during intermittent dynamic exertions of low to moderate intensity. European Journal of Applied Physiology, 85, 299–309.
43.
Nussbaum, M. A., Clark, L. L., Lanza, M. A., & Rice, K. M. (2001). Fatigue and endurance limits during intermittent overhead work. American Industrial Hygiene Association Journal, 62, 446–456.
44.
Öberg, T., Sandsjö, L., & Kadefors, R. (1990). Electromyogram mean power frequency in non-fatigued trapezius muscle. European Journal of Applied Physiology, 61, 362–369.
45.
Öberg, T., Sandsjö, & Kadefors, R. (1994). Subjective and objective evaluation of shoulder muscle fatigue. Ergonomics, 37, 1323–1333.
46.
Ohlsson, K., Attewell, R. G., Pålsson, B., Karlsson, B., Balogh, I., Johnsson, B., et al. (1995). Repetitive industrial work and neck and upper limb disorders in females. American Journal of Industrial Medicine, 27, 731–747.
47.
Pottier, M., Lille, F., Phuon, M., & Monod, H. (1969). Étude de la contraction statique intermittente [A study of intermittent static contractions]. Le Travail Humain, 32, 271–284.
48.
Rainoldi, A., Bullock-Saxton, J. E., Cavaretta, F., & Hogan, N. (2001). Repeatability of maximal voluntary force and of surface EMG variables during voluntary isometric contraction of quadriceps muscles in healthy subjects. Journal of Electromyography and Kinesiology, 11, 425–438.
49.
Rohmert, W. (1973). Problems in determining rest allowances: Part 1. Use of modern methods to evaluate stress and strain in static muscular work. Applied Ergonomics, 4, 91–95.
50.
Sommerich, C. M., McGlothlin, J. D., & Marras, W. (1993). Occupational risk factors associated with soft tissue disorders of the shoulder: a review of recent investigations in the literature. Ergonomics, 36, 697–717.
51.
Sundelin, G. (1993). Patterns of electromyographic shoulder muscle fatigue during MTM-paced repetitive arm work with and without pauses. Occupational and Environmental Health, 64, 485–493.
52.
Veiersted, K. B. (1994). Sustained muscle tension as a risk factor for trapezius myalgia. International Journal of Industrial Ergonomics, 14, 333–339.
53.
Vøllestad, N. K. (1997). Measurement of human muscle fatigue. Journal of Neuroscience Methods, 74, 219–227.
54.
Westgaard, R. H. (1988). Measurement and evaluation of postural load in occupational work situations. European Journal of Applied Physiology, 57, 291–304.
55.
Westgaard, R. H., Vasseljen, O., & Holte, K. A. (2001). Trapezius muscle activity as a risk indicator for shoulder and neck pain in female service workers with low biomechanical exposure. Ergonomics, 44, 393–353.
