Our Endurance Fuel does not have protein in it for one big reason: protein is harder to digest (a contributor to GI distress) when you are exercising! Protein is essential for exercise recovery and overall nutrition, but not during activity. We recommend consuming a little protein at least an hour before you begin exercising, and absolutely including protein with your recovery after.
That being said, it is fine to consume Recovery Mix during a longer endurance event. It is a great alternative to solid food during especially long feats since it is easier to digest. We have a blog where some of our athletes shared their experience with using Recovery Mix during exercise. You can read it (here).