Does leaning posture on the kitchen counter alleviate workload on the low back and legs during dishwashing?

In this study, we evaluated the effects of leaning posture on the kitchen counter, which was observed during dishwashing in a kitchen, on subjective discomfort and muscle activity in the low back and legs. Twelve female volunteers were asked to wash plates for 30 min in each of three working postures: (a) without support (No support), (b) supported by the kitchen counter (Counter), and (c) supported by a standing aid which was a stand equipment to support the shins and the counter (Aid and counter). In the "Aid and counter" posture, the angle of the bent trunk and the muscle activity in the low back were less than that in the "Counter" posture, which was less than that in the "No support" posture. Also, the muscle activities in the legs were greater in the "Counter" and "No support" postures than in the "Aid and counter" posture. We concluded that the effects of leaning posture on the kitchen counter were not enough to decrease the workload on the low back and legs. To improve the comfort of the dishwashing task, new measures, such as the standing aid, are needed.