If you're lounging on the couch tonight, alternate episodes of Sex Education or Virgin River with quick exercises. Love TV? Use commercial breaks for simple moves.
The easiest way to workout is an active lifestyle: time in the gym, sports field sessions mixed with cycling to the supermarket, stairs over elevators, and sprinting for the bus. Even couch time counts—add occasional muscle training.
For example, keep two small dumbbells by the couch or a skipping rope under the TV. Seeing them boosts the chance you'll grab and use them.
Image: Getty Images

How do you start running if you've never done it before?
20-minute workout that only requires a staircase
Get into shape quickly