Dr. Tim Noakes in 1986 stated in his book * the Lore of Running* that a solution of up to 6% glucose does not slow absorption of water. (Since then I’ve read that can be up to 8% or even 10%). Outside states only up to 4%. What is the straight dope? I note that Dr. Noakes referred to many studies.
I usually dilute my sports drink mixes more than the instructions state. A lot depends on the outside temperatures. For example it’s going to take about the same amount of calories to ride my bicycle 100 miles on cold, warm, or hot days. However the amount of fluids (and minerals) required are going to be greater on a hot day. Therefore I’ll dilute the mixture on a hot day so that I can drink more fluids. I may also add something like a ZUUM pill or add some Lite Salt for extra sodium and potassium when I’m going to be sweating a lot.
*Outside *cites no studies to support their claim, just some trendy drinks. And they’re flat out wrong that hydration is only about hydration(Ooh, catchy). Maybe when you’re just hiking, it’s possible to get carbs and electrolytes with food but it’s harder on a bike and near impossible when running.
I dilute sports drinks by half and I’ve never had trouble with electrolyte balance or fluid left in my stomach.