Differences in low back load between kneeling and seated working at ground level.

The effects of the load on the low back when working in a kneeling posture were compared to those when working on a chair designed to alleviate work load in harvesting radish. In 10 male subjects data regarding back muscle fatigue and length changes of the spine, and estimates of experienced discomfort were collected. The results show that for all three effects of back load working on the chair leads to lower levels as compared to working kneeling. However, back load and discomfort were lower when working on the chair, back discomfort still increased substantially during the work on the chair. It is thus a sub-optimal solution from an ergonomic point of view, but at present it could be recommended to allow for variation with the conventional working method.