Is this something that only and dominants are capable of doing consistently? I went through a year of attempting it myself and I'd be consistent until about one month, which I will just fall apart and have to start over. This vicious cycle prompted me to quit realizing that this wasn't for me and it was not worth wasting the time and money. It's like my and did activate sometimes when it was required, but it burnt out like a fuse. However, is enjoying or being driven to do physical work linked to a sensory function?
Most people I know that actually succeed in becoming muscular or very fit are usually and dominants like ESTps and ISTps. Is it practically impossible for an INTj to become muscular? I don't think that's necessarily the case, but it would be much more difficult in general. Now, I have seen and dominants quit after consistency and go through cycles of inactivity, however most of them actually achieved their goal and went back to it. I in the other hand never got close.
In the other hand, an activity such as jogging might be better suited to ENXj's for the fact that they are able to ignore the pain and jog for longer periods due to their polr. This is one activity that I did not have much trouble doing and I lost weight when it was needed and kept this up consitently for more than a month, so I guess there are a lot of factors to take into consideration.