"I just worked a 10 hour shift climbing around this airplane, walking all over the place, lifting and struggling with heavy parts....it has been a workout in itself, so I don't really need to go to the gym tonight".
On my way home, I force myself to change lanes and make that turn towards the gym. I tell myself that I'm just going to walk on the treadmill then go home. Once I get in the gym and in my workout clothes, I snap into gym mode and end up doing my treadmill, all my weight lifting and core work.