NOT ONLY LETTING YOURSELF DOWN 
When you have a gym buddy, you would probably arrange a few days in advance what days you’ll be going to the gym. This means that your buddy now has plans with YOU. If you don’t feel like going to the gym on the day, not only will you be letting yourself down, but you’ll also be letting your buddy down too. The thought of letting somebody else down as well as yourself is a bit more pressing, so you’ll probably face the fear and head on down to the gym, especially with a little encouragement from your bud.