Inorder to understand human limited capability, we need to have some knowledge in Anthropometry, Biomechanics, Anatomy, Physiology and also Pyschology.
What is the indicator to say that the human limited capability is overburdened by the factors existed in the work environment?
Generally, we can say that when the safety and health of the human is affected, there is a factor in the environment causing it. To be specific, from ergonomics perspective, if the human or worker suffers from Musculoskeletal disorder(MSDs), there is always a physical overburden created by his work environment.
God The AlMighty had created human with this limited capability and we cannot change it. The only thing we can change is what we have created in our work environment : - the workplace design and the work (job & task) arrangement, i.e. the second component of the worker-work environment (W-WE) ecosystem.