A medical doctor says Trump's forward leaning stance is because he wears lifts on his shoes. Add the obesity, and he looks like he's about to topple over.
“In the past several days, it’s been reported that Donald Trump has been “standing weird”. Although the President’s leaning-forward posture has been displayed in the past, recently this stance has been used more consistently. Why? What are the body language ramifications?
Donald Trump is standing with this posture — primarily because he has specially crafted, ‘lift shoes’. His added 2.5–3.5 inch heel-height causes him to lean forward. This configuration is accentuated by his obesity.”
A different take on this posture is from Tom Joseph on Twitter who considers that the stance derives from frontotemporal dementia:
Either from his desire to be taller than Obama or a symptom of prefrontotemporal dementia, who knows for sure? But stand up and put both arms in front of you, and you'll realize this is not normal!! Oddly enough this not normal stance lacks any serious comment from the mainstream media. Why not?