Out Of Shape
I don't know about you, but I go months without working out. I then decide to go back to the gym but am so out of shape that I get discouraged.  Well, Buzzfeed captured this feeling in a hilarious video I'm sure you'll appreciate.
Junk Food
Running on the treadmill, picking up the medicine ball and riding a stationery bike are all exhausting, so why not supplement your workout with a reward that tastes delicious?