15 years ago the hydration system revolution was in full swing.  Hoses and bladders were ubiquitous for day hiking, mountain bikers, backpackers, and even runners.  Bladder tech has only gotten better since; after holding out for years against more gadgets I must admit that the quick disconnect that came with the latest Osprey is darn handy, if not altogether foolproof.  For multiday backcountry pursuits (aka backpacking and its variations) bladders have big issues: they’re clumsy to fill on the go, they often don’t play well with a full pack, and they can break and leak (which often goes undetected until too late).  But the argument bladders made is incontrovertible; that while backpacking a significant amount of water needs to be accessible all the time, ideally with one handed access and removal.  Pack makers of all stripes have had to up their game, and side pockets are much better than they used to be.  Side pocket bottles aren’t always the best solution for the backcountry, but when they are done well they’re preferred 95% of the time.

(The big exception being toting 3+ liters, like below, where bladders are much more compact and you want that weight closer than side pockets can achieve.  Hoses are also largely backwash-proof, handy for toddlers and their disgusting drinking habits.)

Recently there has been a push-back against “overhydration” and the marketing language (hydrate or die!) with which the hydration pack industry has flourished.  While I think many of the particulars of this criticism have merit, on the whole it is profoundly misguided, especially when it comes to multiday backcountry pursuits.

First, the hydration pack industry is indeed a bit much.  Charging 150 bucks for a “technical daypack” isn’t the most utilitarian development the outdoor industry has cooked up, but like with puffy coats the technology bleeds over and the cash keeps companies and retail stores afloat.  For dayhikers who think water purification is a survival necessity, chic 25 liter bags with a 100 ounce bladder makes sense.

Second, the term overhydration isn’t really accurate.  Hyponatremia is about excessively low blood sodium.  It is very easy, especially in decent heat, to drink enough while taking in too few electrolytes, which if taken too far can lead to some pretty bizarre symptoms, and death.  It is only slightly less easy to drink much faster than your gut can absorb, which only results in lots of pissing.  I have no doubt that many, many people have and will continue to drink more water than their body can absorb (1 liter/hour for a 150 pound person, under ideal conditions), and that only some of them could have put most of that water to actual use with better nutrition, but I am certain that to this day many more still drink too little and cruise around dehydrated and underperforming, all other factors considered equally.  Overhydration and hyponatremia are simply never the same thing.

Third, “drink when you’re thirsty” is not inherently inaccurate but doesn’t begin to tell the whole picture, and for the multiday backcountry athlete (meaning someone who works hard and tends to sweat on their trips) is a principal incomplete enough to be actively dishonest.  While you may only be able to process a half liter an hour while hiking hard, you could lose 3-6 times that amount during the same time, through perspiration and respiration.  Do that math; 2 liters of loss average over 14 hours on the move is 28 liters.  Cut that in half for a less severe hypothetical; when and how are you going to replace over 3 gallons of fluid during a 24 hour period, especially when you’re asleep for a third of it?  Drinking when thirsty is unlikely to get the job done.

The vital point here, and the reason why the often cited literature from Noakes et al is of little utility for backpackers, is that day to day recovery and maintenance has to be entirely self contained.  Even a tough, slow marathon is perhaps equivalent to one full on days backpacking effort, and virtually no one running Fog City or Whiskey Row has to hydrate and eat with an eye towards doing the same thing for the following five days.  Even a longer race like the much researched Comrades Ultra doesn’t generalize to multiday backcountry particularly well due to the recovery aspect.  Not everyone backpacks like this, but lots of people stepping out on more severe trips, especially in hot areas like the Grand Canyon or Colorado Plateau get slapped down after the first two days, and my personal experience has led me to believe that many if not most of these folks would do and feel better with a more aggressive and holistic hydration and nutrition strategy.

Food for the 2011 Wilderness Classic.

I wrote some detailed guidelines for food planning for a backpack a few years ago, but for the purposes of this post it is illustrative to look at the food I brought on the Wilderness Classic six years ago.  That was a ~150 mile effort that ended up taking 3.5 days, with weather that trended more towards cold and wet than warm and dry.  Lots of chocolate and cheese and nuts was geared towards the cold weather aspect, as well as calorie/oz maximization, but I also had lots of salty and easy to digest foods along, the kinds of things (Pringle’s, licorice, Paydays) I usually bring on warmer weather trips, but also take on more strenuous outings.  Simple soups and hot cereals are not only psychologically beneficial, but seem to help get nutrients and especially fluids on board, not only in the stomach but into the blood stream.  The food above ended up being just about perfect, I even had a few extra Snickers to share with Paige, but some drink mixes and/or electrolyte supplements would have been an ideal addition.

It’s common for the uninitiated to look at food lists like the above and see little other than junk food.  That is true, but what is also true is that things like Pringle’s and chocolate and Halvah are well suited to the demands of multiday backcountry outings, especially strenuous ones.  Rules still apply, but they are very different ones.