The suggestion that they made, which I think is a brilliant idea, is to commit to a
4 MINUTE WARM UP.
Basically do what you were planning to do for just 4 minutes.
Walk for four minutes.
Head to the gym for 4 minutes.
Get out on your bike for 4 minutes.
If after the 4 minutes you can get up and walk away thats fine. However the chances are, after 4 minutes, you might not actually feel like stopping. You might even want to carry on because you're kind of getting into it.
Commit to the 4 minute warm up, no matter how 'can't be bothered' you feel.