Not many people in the world get out of bed and say " Yay time to do some exercise ! " because honestly exercise is not always fun. But there are lots of ways to enjoy exercising and look forward to it everytime you decide you need it :)
Why not go for a bike ride on a sunny day. This is good exercise and lots of fun.
If you need to go for a run but really don't want to, ring up a friend and see if she wants to come too.
Go for a swim at the local pool or if you have a pool at home go for a swim there, this is relaxing and great exercise.
Why not go rollerblading. This is so much fun and still counts as exercising.
Do some dancing, this will make you break a sweat but is lots of fun!
So next time you don't want to exercise, become motivated and find a fun way to do it!