If we are able to carry a weight of 40 Kg comfortably, we may try 45 Kgs that too once in a while only not regularly. But we should never attempt 60 Kgs which is 1.5 times what you can manage. That will definitely trouble you a lot and you may get physically hurt also sometimes.
This burden need not be physical and then can be even mental stress also. We will be always thinking about something or the other and we will be getting stressed with multiple things in the mind and that stress may lead to anxiety disorder.
As long as we take care of our body properly it will help us and we will not have any discomforts. But the moment you start abusing the same by loading more and more works, you may have to pay the penalty.
"Life is easier when you enjoy what you do"
K Mohan @ Moga
'Idhuvum Kadandhu Pogum "
Even this challenging situation would ease