It's even worse when one uses "common" as proxy for "normal"/"healthy".

EG see: https://x.com/hjluks/status/1943754923570520483

Seems like exactly the opposite. He is saying the common finding (75% of people) is abnormal.

He also says "These weren’t overweight or sedentary individuals" which makes me think he didn't thoroughly read the abstract, which says the main finding is that sedentary people have decreased markers of mitochondrial respiration relative to moderately active people.