"What about this one for horses? It seems a little more basic:"

A step in the right direction, but I'm still a bit sceptical because I'm not sure where magnesium sulfate,potassium sulfate, and calcium lactate pentahydrate fit in.
Personally, I prefer to keep it simple with compounds I'm familiar with, e.g sodium chloride, potassium chloride, magnesium oxide, and calcium carbonate. I'm also comfortable with citrate salts of the above, especially calcium citrate. This is not to say the Farnam product is bad, just that I'd be a bit reluctant to try it, especially since they don't specify the proportions of the different salts in the product. If you do decide to give it a try, would you post back on your results? I, for one, would be interested to hear how it turns out.

I like the Emergen-C fizzy packs or other electrolyte fizzies. You can find many brands in any health food store. You can also try the electrolytes in tablet form, but they take a bit of time to dissolve in your tummy. Again, many brands in athletic stores or health food stores. You can match the dose to you expected activity level and weather conditions.

In this area I kind of lean towards what Eugene Smith said;

"Drink water consistently, stay on top of your caloric intake (eating foods you mentioned), and keep the sun off your skin as much as you can".

I don't mean to oversimplify things but I find that staying fueled up means adequate water intake, fuel (food) and I supplement this with walking snacks of Clif Bars. They are a good source of calories and electrolytes.

Also I will on occasion use a weak mix of a sports drink like Gatorade. It can help with taste issues and the electrolytes are an added bonus in staying fueled up for hiking. I've recently moved back towards the H2O only but I'll carry a 20 oz bottle of pure Gatorade or some of the powder to mix in if I feel it's necessary.

The downside of the liquid Gatorade and Clif Bars is the weight. You can offset the liquid weight by carrying the powder and mixing your own.

I've used this method with good success since I bonked badly in my local state park about a year and a half ago. YMMV

Party On,

Newton

Personally, I will carry the weight of powdered electrolyte mix (or even drink mix, see below) and my personal favorite is Cytomax. Here's why:

--comes in an Orange flavor that tastes like Tang. I love Tang. Astronauts used Tang.

--uses complex sugars, rather than sucrose that's in Gatorade and...Tang.

--includes an electrolyte and lactic acid buffer mixture that's very effective.

--I know it's very effective because the US Olympic Team and US Olympic Training Center in Otay Mesa, California use Cytomax. In fact, just before the Sydney Olympics, one of my employees was an Olympic rower who lived at the OTC and, over the course of discussion about her extremely limited diet (bag lunches from the OTC kitchen, to ensure no failed blood tests due to some surprise ingredient at a restaurant), I learned that Cytomax not only "cleared" the OTC limitations but was popular with the athletes. Heck, it was already popular with me.

--So, it tastes like what the astronauts use, works well for Olympic athletes and can be purchased in big tubs from bike shops. Done. It even comes in grape and a disgusting lemon-lime, ha ha! (Two other flavors of Tang over the years.)

I think metabolisms vary, but on long runs (3+ hours) if I don't supplement electrolytes I will feel the effect, hiking pace probably not near the worry.

I use one endurolyte and one saltstick/hour, for me the endurolytes didn't have enough Sodium (this surfaced on our Grand Canyon run where the last couple of hours my stomach was in great distress) 40mg vs 215mg for the Saltstick

I get additional electrolytes (and calories) w/ Cliff shot blocks and Perpetuem

the stomach distress compounds problems as you don't want to eat or drink and yet you know you have to, not fun

After a lot of reading, I found that stomach distress during ultras is often (not always) due to lack of Sodium, knock on wood I haven't experienced that distress since

I've used this same strategy on a couple of 30+ mile day hikes w/ no ill effects