Originally Posted by
Machoman121
So far 3 rides with the protein drink and no cramping.
It sounds like your fitness is improving which is logical if you're relatively new to riding or are in the process of ramping your training time. It does make it difficult to isolate which factor is responsible for the benefit.
Protein is a poor fuel for biking as it takes too long to metabolize. My guess is the cramping will subside as you gain fitness and you'll be able to ride with just water for 2-3 hrs.