Admittedly my contribution is a high calorie option, but it’s delicious, and it works for me. I usually limit it to big time workouts (1000cal+) and I certainly don’t add dextrose unless it’s at least an hour or more of intensity. For stuff like Pettit, I’ll just drink tart cherry juice and eat my normal breakfast which has pretty good protein. Stolen from Paleo Diet for Athletes, and modified:
8oz tart cherry juice (usually from concentrate)
1 medium banana
1 scoop vanilla whey protein isolate
(Optional: additional TBSP of dextrose, I do 1 per hour of intensity, tempo plus)
Dash of salt
450 cal without added sugar. Each additional TBSP of dextrose is +35 cal. Basic recipe is about 3:1 ratio. Add two scoops of dextrose and you’re close to 4:1.
Reduce the juice by half or drop the banana and do a half scoop of protein powder and you’re under 300 cal and 4:1.
I may play around with chocolate milk and/or Recoverite for a lower cal option, but I generally like real food options as much as possible. I used EnduroxR4 for a long time, but I don’t like paying that much for stuff and again like real food as able.