At a mean load level typical for industrial manual work, muscular strain of the triceps brachii muscle highly depends on the load change ratio - preliminary results of an exploratory study

Promoting mechanical exposure variation through muscular load changes is suggested for preventing musculoskeletal disorders related to industrial manual work. Knowledge about the influence of different muscular load change ratios (LCRs) on muscular strain is still incomplete, especially at load levels realistic in industrial manual work. This exploratory study examines differences in muscular strain responses to five different LCRs. All measures showed that the lower the LCR, the higher the muscular strain response. This association appears to be non-linear with similar strain responses for higher LCRs. The study indicates two central aspects. First, LCR level is crucial for a sufficient reduction in muscular strain. Second, the effectiveness of muscular load changes on muscular strain appears to level off above a certain limit. Further research needs to verify these findings using greater and more diverse populations and should determine a physiologically relevant strain reduction induced by mechanical exposure variation.