Marathon Water Station

Liquid Hazards



In 2009, I raced the USA Marathon Trail Championships. It was my fifth marathon and I achieved my goal of becoming national masters champion. While accomplishing this goal was valuable, I may have learned a more valuable lesson that all runners can apply to their marathon racing.

Unlike most road marathons, where there is an aid station every mile or two, in the trail marathon championships the first aid station was at mile 8, the second at mile 16 and the third (and last) at mile 21. This forced all competitors to carry their own fluids, something I’d never done in a race.

In preparation for the race, I tried out several hydration systems to see what would work best at race pace. I already knew my best nutrition strategy from previous marathons, so I simply began to carry my fluids on long training runs. Over time, I realized that while I always thought carrying fluids was only for ultramarathoners, it might also be the best way for non-elite runners to fuel while racing the marathon.

My rationale included both the danger posed by water stops and the difficulty of rehydrating properly using them. Fluid stations at most marathons have become so congested that runners often lose valuable time just trying to get to the cups of water and sports drink. And who can drink from those cups at race speed? It’s so hard to get in what you need. Plus, what if you drop your cup, a volunteer misses the hand-off, another runner cuts you off or knocks the cup out of your hand, or any number of other potential accidents occur while you’re getting your fluid? If you look at photos of fluid stations, you’ll see a lot of stressed-out and slowed-down runners.


Why not just carry your own? Nearly all marathoners should consider this strategy. Here are my reasons why:

  • You’re in charge of your own destiny–no more mishaps at fluid stations.
  • You can drink on your own schedule–I like to drink two to three good-sized swallows every 15 minutes, until the last hour of the race when I drink every 10 minutes.
  • You can drink what you want to drink. Carrying exactly what you’ve found works for you is so much better than having to rely on the supplied drinks, which may or may not work for you.
  • You don’t have to slow down. No more slowing, weaving, bobbing and grabbing at fluid stations. Just cruise by them.
  • You can remove one more race-day stress.


First, you have to make peace with adding weight. We typically want to be as light as possible while racing (hence lightweight racing flats instead of heavier training shoes). One ounce of water weighs 0.0652 pounds. At first I was concerned with this, but I found that I never really noticed the weight; after all, it’s marathon pace, not 5K pace. I certainly felt the benefit of better fueling that comes with carrying fluids was worth the added weight early in the race. Of course, you also get lighter as the race goes on.

Second, you’ll have to try several types of fluid packs to find the one that fits you best and minimizes bouncing. I tried on several at the store and purchased three different styles. After several runs, one stood out and became my race pack. Packs are so advanced now and come in so many different styles that I suspect every runner can find one that works.

Third, you have to calculate how much fluid you’ll need. One standard-sized water bottle, holding 21 ounces and weighing 1.369 pounds, is plenty for me on a normal marathon day, but every runner is different. A runner finishing in 3 hours will obviously need less fluid than someone finishing in 5 hours. As with most things in running, I learned from training runs – several of which lasted near my goal marathon finishing time – just how much I would need. Of course, I knew I could always supplement what I carried with the on-course fluids.

Fourth, you have to practice your fluids in training. This is something you do anyway, and carrying your own fluids makes this process a breeze. No more stashing bottles hoping they’ll still be there when you return, no more finding someone to help you out, and no more agonizingly long fluid breaks. Instead, you can focus on running smart, getting in your nutrition and hydration and dreaming of a new PR.


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Written By Greg McMillan
Called “one of the best and smartest distance running coaches in America” by Runner’s World’s Amby Burfoot, Greg McMillan is renowned for his ability to combine the science of endurance performance with the art of real-world coaching. While getting his graduate degree in Exercise Science he created the ever-popular McMillan Running Calculator – called “The Best Running Calculator” by Outside Magazine. A National Champion runner himself, Greg coaches runners from beginners to Boston Qualifiers (15,000+ and counting!) to Olympians.

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