Isokinetic Lifting Strength and Occupational Injury

Epidemiologic study of low back pain in 1398 Swiss conscripts between 1985 and 1992

“…Bigos et al [11] observed that a preliminary history of LBP was associated with the recurrence of LBR Biering-Soerensen [8], however, revealed that the greater the time which had elapsed since the last episode of LBP, the lower the risk of recurrence. Other authors did not even find a significant association between preliminary LBP and the recurrence of LBP [29,34,36]. Our results confirm these previous observations, i.e., a preliminary history of LBP within the last 12 months or 7 years ago was not predictive of recurrence.…”

“…Thus, chronic LBP (i.e., LBP associated with medical visits in 1985 and 1992) was associated with standing or twisting. The following occupations have been currently associated with frequent or chronic LBP: construction workers [25], farmers or livestock breeders [3,14,51], nurses [15,22,27,36,51], and physiotherapists [35]. Other high-risk occupations are those which are regularly subject to vibration or repeated shocks, such as tractor [3], bus, crane, or other professional drivers, truckers [2,7,43], and helicopter pilots [19].…”

The Role of Genetics and Environment in Lifting Force and Isometric Trunk Extensor Endurance

“…Lifting force is lower in adults over 45 years of age than in younger adults. 3,5,8,9 Similar findings have been reported for isometric trunk extensor endurance time 5,10,11 and for muscle force and trunk extension torque measured during isometric contractions while standing, sitting, and lifting using isokinetic devices and testing protocols with a range of motion of 0 to 80 degrees of flexion and speeds of 30°/s to 120°/s. 6,10,[12][13][14] However, the influence of age, spanning from young through middle adulthood, on trunk muscle force is less clear.…”

“…3,11 However, weight had no effect on isokinetic trunk extension and lifting mean peak force in patients with LBP. 9,13 Effects of physical activity on tests of low back muscle performance are controversial, which may be explained, in part, by variations in definitions of physical activity and difficulties with its accurate measurement. In some studies, 2,3 no difference in peak force (measured with 0°-80°of flexion and speeds of 60°-120°/s and 0.5 m/s) was found between active and inactive subjects with or without back problems.…”

“…10,15 Different aspects (intensity and duration) of LBP history have been shown to have an influence on measurements of low back muscle performance in the majority of studies of nonpatient samples, 7,10,15,[17][18][19][20] but not in all studies. 3,9,12,21 We contend that the apparently conflicting results were due, at least in part, to definitions of current back pain (pain present either during testing or during the test day) or past back pain (an episode of LBP or frequency of LBP over the prior year) 3,9,12,21 and to severity of the episodes of LBP (as determined by visual analog scale rating for pain or difficulty in performing different tasks). 3,21 Severity of pain and other aspects of LBP in studies of patients with chronic LBP also have been associated with low back muscle performance.…”