The secret is that the most difficult thing is to get started. Once you got started you 95% most likely to finish the whole 30 minutes work out!
Even if you just do one exercise for 10 times, it is better that nothing. You wouldn’t feel guilty and depressed – you’ve fulfilled your assignment! And if you do more you’ll feel even better!
The trick is to give yourself a really small task:
To make a phone call, or to read one page of a textbook.
And once you get started you will actually find out that you won’t mind doing more than you planned!
Remember, set big goals, but make your tasks small.