Sometimes life gets in the way of regular training and when you get back to it, your level is not what it used to be. With the new Experience profile graphs (coming soon), if you're away from training for a while, that will automatically regress your level. But if you have a sudden drop in your abilities, for example due to an injury, there is no way to ask the app to adapt to that. Besides adapting to your reduced abilities, it could be useful to look back on your injury track record, see how long it took you to recover, identify patterns more easily, ...