Strength testing has been used to determine a worker's physical capacity as well as to screen an individual for placement in future employment. A comparison is made of the relationships between two types of strenght tests (isometric and isoinertial) and the manual materials-handling (MMH) capacities of individuals. Four MMH activities were evaluated: lifting from floor to knuckle height, lifting from knuckle to shoulder height, lowering from knuckle to floor height, and carrying for a 4.3-m distance. Psychophysical capacities were determined under three frequency conditions: one-time maximum, 1 lift/min, and 6 lifts/min. I soinertial 1.83-m maximum strength (Tl), tested on the incremental weight-lifting machine, proved to be the most highly correlated strength test to the capacities for MMH activities. Second-order polynomial regression models for MMH capacities were developed using T1as a predictor. The isoinertial strength test T1 is recommended as the most promising single screening test because of its simplicity and task similarity.
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References
1.
Aghazadeh, F. (1982). Simulated dynamic lifting strength models for manual lifting. Unpublished doctoral dissertation, Texas Tech University, Lubbock, TX.
2.
Allen, D. M. (1971). Mean square error of prediction as a criterion for selection variables. Technometrics, 13, 469–475.
3.
Allen, D. M. (1974). The relationship between variable selection and data augmentation and a method for prediction. Technometrics, 16, 125–127.
4.
Anderson, T. M. (1951). Human kinetics and analyzing body movements. London: William Heineman.
5.
Asfour, S. S. (1980). Energy cost prediction models for manual lifting and lowering tasks. Unpublished doctoral dissertation, Texas Tech University, Lubbock, TX.
6.
Ayoub, M. M. (1980). Reference manual for an anthropometric survey. Yellow Springs. OH: Anthropology Research Project.
7.
Ayoub, M. M., Bethea, N. J., Deivanayagam, S., Asfour, S. S., Bakken, G. M., Liles, D., Mital, A. and Sherif, M. (1978). Determination and modeling of lifting capacity (Final Report, HEW [NIOSH] Grant No. 5R010H000545-02). Cincinnati, OH: NIOSH.
8.
Ayoub, M. M., Denardo, J. D., Smith, J. L., Bethea, N. J., Lambert, B. K., Alley, L. R., and Duran, B. S. (1982). Establishing physical criteria for assigning personnel to air force jobs (Final Report, Contract No. F49620-79-C-006). Bolling AFB, DC: Air Force Office of Scientific Research.
9.
Ayoub, M. M., Gidcumb, C. F., Hafez, H., Intaranont, K., Jiang, B. C., and Selan, J. L. (1983). A design guide for manual lifting. Manuscript submitted for publication.
10.
Ayoub, M. M., Mital, A., Bakken, G. M., Asfour, S. S., and Bethea, N. J. (1980). Development of strength and capacity norms for manual materials handling activities: The state of the art. Human Factors, 22, 271–283.
11.
Ayoub, M. M., Sclan, J. L., and Jiang, B. C. (in press). Design for health and safety: Manual materials handling. In Handbook of human factorslergonomics.New YorkWiley.
12.
Bakken, G. M. (1983). Lifting capacity determination as a function of task variables. Unpublished doctoral dissertation, Texas Tech University, Lubbock, TX.
13.
Bassey, E. J., McDonald, L. A., and Patrick, J. M. (1982). Factors affecting the heart rate during self-paced walking. European Journal of Applied Physiology, 48, 105–115.
14.
Brown, J. R. (1973). Lifting as an industrial hazard. American Industrial Hygiene Association Journal, 34, 292–297.
15.
Caldwell, L. S. (1970). Decrement and recovery with repetitive maximal muscular exertions. Human Factors, 12, 547–552.
16.
Cattell, R. B. (1966). The meaning and strategic use of factor analysis. In R. B. Cattell (Ed.), Handbook of multivariate experimental psychology (pp. 174–243). Chicago: Rand McNally.
17.
Chaffin, D. B. (1975). Ergonomics guide for the assessment of human static strength testing. American Industrial Hygiene Association Journal, 36, 505–510.
18.
Chaffin, D. B., Herrin, G. D., Keyseding, W. M., and Foulke, J. A. (1977). Pre-employment strength testing (Tech. Report DHEW [NIOSH], Publication No. 77-163). Cincinnati, OH: NIOSH.
19.
Ciriello, V. M., and Snook, S. H. (1983). A study of size, distance, height, and frequency effects on manual handling tasks. Human Factors, 25, 473–483.
20.
Draper, N., and Smith, H. (1981). Applied regression analysis (2nd ed.). New York: Wiley.
21.
Drury, C. G., Law, C. H., and Pawenski, C. S. (1982). A survey of industrial box handling. Human Factors, 24, 553–565.
22.
Drury, C. G., and Pfeil, R. E. (1975). A task-based model of manual lifting performance. International Journal of Production Research, 13, 137–148.
23.
Dryden, R. D. (1973). A predictive model for the maximum permissible weight of lift from knuckle to shoulder height. Unpublished doctoral dissertation, Texas Tech University, Lubbock, TX.
24.
Garg, A., and Ayoub, M. M. (1980). What criteria exist for determining how much load can be lifted safely?Human Factors, 22, 475–486.
25.
Garg, A., Mita, A., and Asfour, S. S. (1980). A comparison of isometric strength and dynamic lifting capacity. Ergonomics, 23, 13–27
26.
Goldberg, H. M. (1980, June). Diagnosis and management of low back pain. Occupational Health and Safety, pp. 14–15.
27.
Griffin, A. B., Troup, J. D., and Lloyd, D. C. E. F. (1984). Tests of lifting and handling capacity---Their repeatability and relationship to back symptoms. Ergonomics, 27, 305–320.
28.
Hafez, H. A. (1984). An investigation of biomechanical, physiological and environmental heat stresses associated with manual lifting in hot environments. Unpublished doctoral dissertation, Texas Tech University, Lubbock, TX.
29.
Hoed, A. E. (1962). Application of ridge analysis to regression problems. Chemical Engineering Progress, 58, 54–59.
30.
Hoed, A. E., and Kennard, R. W. (1970). Ridge regression: Biased estimation for non-orthogonal problems. Technometrics, 12, 55–67.
31.
Hotelling, H (1933). Analysis of a complex of statistical variables into principal components. Journal of Educational Psychology, 24, 417–441, 489-520.
32.
Jiang, B. C. (1984). Psychophysical capacity modeling of individual and combined manual materials handling activities. Unpublished doctoral dissertation, Texas Tech University, Lubbock, TX.
33.
Jones, D. F. (1971). Back strains: The state of the art. Journal of Safety Research, 3, 28–34.
34.
Kamon, E., and Ayoub, M. M. (1976). Ergonomics guides to assessment of physical work capacity.Akron, OH: American Industrial Hygiene Association.
35.
Kamon, E., Kiser, D., and Pytel, J. L. (1982). Dynamic and static lifting capacity and muscular strength of steelmill workers. American Industrial Hygiene Association Journal, 43, 853–857.
36.
Knipfer, R. E. (1974). Predictive models for the maximum acceptable weight of lift. Unpublished doctoral dissertation, Texas Tech University, Lubbock, TX.
37.
Kroemer, K. H. E. (1983). An isoinertial technique to assess individual lifting capability. Human Factors, 25, 493–506.
38.
Lahey, J. W. (1984, March). Bearing down on musculoskeletal disorders. National Safety News, 37–39.
39.
Legg, S. J., and Pateman, C. M. (1984). A physiological study of the repetitive lifting capabilities of healthy young males. Ergonomics, 27, 259–272.
40.
Macintosh, D (1974). The structure and nature of strength. Journal of Sports and Medicine, 14, 168–177.
41.
McDaniel, J. W. (1972). Prediction of acceptable lift capacity. Unpublished doctoral dissertation, Texas Tech University, Lubbock, TX.
42.
McDaniel, J. W., Shandis, R. J., and Madole, S. W. (1983). Weight lifting capabilities of Air Force basic trainees (AFAMRL-TR-83-0001). Wright-Paterson AFB, OH: Air Force Aerospace Medical Research Laboratory.
43.
Mital, A (1980). Effects of task variable interactions in lifting and lowering. Unpublished doctoral dissertation, texas Tech University, Lubock, TX.
44.
Mital, A., Ayoub, M. M., Asfour, S. S., and Bethea, N. J. (1978). Relationship between lifting. In Proceedings of the Human Factors Society 22nd Annual Meeting (pp. 469–473). Santa Monica, CA: Human Factors Society.
45.
Mital, A., and Ilango, M. (1983). Load characteristics and manual carrying capacities. In Proceedings of the Human Factors Society 27th Annual Meeting (pp. 274–278). Santa Monica, CA: Human Factors Society.
46.
Morris, J. D. (1980). The predictive accuracy of full-rank variables vs. various types of factors scores: Implications for test validation. Educational and Psychological Measurement, 40, 389–396.
47.
National Safety Council (1959-1981 eds.). Accident facts.Chicago: Author.
48.
NIOSH. (1981). Cincinnati, OH: U. S. Dept. of Health and Human Services, Center for Disease Control.
49.
neter, J., and Wasserman, W. (1974). Applied linear statistical models. omewood, IL: Richard D. Irwin.
50.
Plott, C. C. (1983). Alternative strength testing methods for employee screening. Unpublished master's thesis, Texas Tech University, Lubbock, TX.
51.
Poulsen, E (1970). Prediction of maximum loads on lifting from measurement of back muscle strength. Progressive Physical Therapy, 1, 146–159.
52.
Smith, J. L., and Ayoub, M. M. (1982). Interim modification of the x-factor test(Final Report, Contract No. F33625-78-D-0629-0037). Bolling AFB, DC: Air Force Office of Scientific Research.
53.
Smith, J. L., and Jiang, B. C. (1984). A manual materials study of bag lifting. American Industrial Hygiene Association Journal, 45, 505–508.
54.
Snook, S. H. (1978). The design of manual handling tasks. ergonomics, 21, 963–985.
55.
Younger, M. S. (1979). Handbook for linear regression. Belmont, CA: Wadsworth.
