Fitness trainer apps or even in-person personal trainers have gained popularity. One main benefit of using these is that they provide authority — someone telling you the best exercises to do so that you don’t have to come up with them and plan out your workouts yourself. In addition, these provide a source of commitment because usually you sign up for a long-term, consistent workout plan. In this sense, it also provides a good routine because you can always expect that you’ll need to complete a certain workout, so it’s easier to build time in for that. However, a big limiting factor for usage of these services is the money to pay for an expensive trainer, as well as time and physical effort.