Starting with the Boise 70.3 I tried out EFS energy drink (yes, I do mean the first time I used it was on a race day–I know, I know, bad idea). I had some gastrointestinal issues that day, but nothing too big. Just some knots in my stomach, and I felt like if I drank any more I would puke. But I didn’t puke, and I thought the reason I couldn’t drink any more was because I didn’t need any more. In retrospect, I’m wondering if I should have been drinking more, but couldn’t because the EFS was harsh on my tummy. But I only came to this thought because as I’ve been drinking it more and more, I seem to be noticing a correlation between a tight stomach and EFS. Again, it’s not that bad, and I’ve never had that “I’m going to throw up if I drink anymore” feeling (I’ve also never made it as goopy as I did for Boise), but the more I drink it, the more tight the correlation seems to be such that I’m thinking there is a cause and effect situation going on.
Other than that, it tastes fine (very subtle, mild flavors), and seems to work fine as an energy source. But if I continue to have the knotted up stomach, I’m going to have to switch back to Heed or something new.