Why exercise may never be effective medicine in the treatment of type-2 diabetes

"If you don't stick to the exercise, your type2 symptoms will come back" and "in reviewing studies, most people don't stick to the exercise beyond a year"

I know several people keeping type 2 at bay with exercise, lifestyle changes (diet) and probably some drugs, but I don't know anyone recruited into an academic study.

Partly I want to say "..yet" because I think a better long term, 5+ year inteverention/support study sounds interesting and I wonder if the lack of funding towards long term study means they only get to re-survey people who had a short term intervention and support. The people know get lots and lots of ongoing positive reinforcement over diet and exercise.

Lots.

I'd suspect the same with bone density and muscle mass for osteopenia, ageing. The people I know who continue are using health funds which provide continuous access to support, physio, year round. Ten, fifteen years of ongoing supervision. Even anti smoking and drinking campaigns show you need ongoing support. A one and done interventions model is never going to work.

Why do they think people stop exercising?