It may be surprising to learn that taking a trip to the mall could have beneficial effects on your fitness motivation. A researcher coined the term "enclothed cognition," which essentially means that what you wear affects your performance.
Study results show that you'll perform better at a given task if you dress suitably for the task at hand. For example, dressing like a personal trainer or a professional cyclist (depending on what activity you choose) has the potential to greatly improve your exercise performance.
So get out there and get a new outfit and hit the gym!