Two minutes.
Right where
you are.
They are called exercise snacks: short bursts of movement spread through the day instead of saved up for one session. These are real physical therapy exercises, two minutes at a time, wherever you happen to be standing.
It has a name
The idea has a name in the research literature, and it is exercise snacks. Short, frequent, and deliberately unimpressive.
Short beats saved up
An hour of movement spread through the day is at least as good as an hour in one go, and may be better for post-meal blood sugar.
Real exercises
These are the same exercises a home physical therapy programme uses. The difference is that they are spread through the day rather than done all at once.