Hi Paulo,

Normalization isn't always warranted and can make interpretation difficult. Only when body size will reasonably influence comparisons should normalization be undertaken. That being said, it may depend on the muscle being tested. If you are testing hip musculature, I suggest this paper: https://www.ncbi.nlm.nih.gov/pubmed/21187208. See references if you are looking for knee musculature. I agree that there doesn't seem to be a consensus on whether force or torque are better measurements of the construct of strength. There may be multiple other reasons to use one measure (force is easier and less time consuming, torque may be more applicable to what the muscle is actually doing). I will typically use torque and normalize to mass and height, when warranted.

David