Seven reasons you shouldn't run a marathon

Kenyan Willy Koitile made winning the 2013 Sydney Marathon look easy. But make no mistake: Completing 42.2 kilometers in Koitile’s 2:13:48 —or even in the average guy’s time of over four hours—is challenging as hell. While more and more of you are signing up to go the distance—in 2013, almost 34,000 people finished the Sydney marathon - it's not always the best idea for any guy to start training to cross a marathon off his bucket list. Sure, anyone can attempt a marathon, and races will gladly take your money, but you might be putting your health at risk in the process if certain things are working against you. Here's a list of reasons not to run a marathon (right now) and how to set yourself up for (relative) success so you can win in the long haul, like Koitile.

A rigorous training regimen requires a smart nutrition plan. If you've been on a tan-food diet—breads, meats, pastas, fried foods—you'll need to add in colour with fruits and vegetables to help fuel your workouts and trim excess fat.

The Fix: Swap processed foods for plant-based or whole foods as often as possible, and knock 100 to 200 calories off each meal for the next six to eight weeks, Patel suggests. Also, now that you're exercising, don't use it as permission to go hog-wild at a buffet after a gym session. “A lot of runners gain weight because they over-estimate how many calories they're burning and how much they need to take in for recovery,” says Patel. Fight the urge to indulge, or at least keep it in check. (Think a plate of hot wings, not a bucket.)

Whether you played sports in school or tore your ACL while skiing, fact is, you may now have a bum knee or two. Shouldn’t you be worried that prolonged activity, especially something as high-impact as running, might cause flare-ups? Not necessarily. You're more at risk of injury sitting on the sidelines and being inactive. “Use it or lose it. A sedentary body can disproportionally get weak or atrophied. This mismatch can lead to injury and damage even at low levels of exercise,” says Brown.

The Fix: One way to log some pain-free miles to get you in shape is at your local pool. With aqua running, all you need to do is strap on a floatation device—like an Aqua Jogger vest—jump in, and mimic running motions in the deep-end for 30 minutes. “It's great for both rehab and cross-training because it goes through the bio-mechanics of running without any impact on your joints,” says Chiplin, who adds that the water resistance makes it a really tough workout. Pair this with a running coach who can improve your form to minimise pain and prevent injury. (Like having your foot land under your center of mass, not in front of you by over-striding.) Or visit your local running store for a gait analysis and proper shoe recommendations. Keep their tips in mind as you train, and stop in again every so often to check on your technique's progress.

It's like New Year's all over again. It’s gung-ho at the beginning to run that sub five-hour marathon, but you eventually lose steam and want to throw in the towel a few weeks into hard training. That could be disastrous on race day. “When you're unrealistic about what you can achieve, you won't progress as planned and everything begins to spiral downward,” says Terry Chiplin, owner and camp director of Active at Altitude, a Colorado-based facility for endurance athletes.

The Fix: Let things unfold organically. If you can't run for more than 10 minutes straight without huffing and puffing, then try running for three minutes then walking for two minutes for a half hour, steadily increasing the running portion over time, Chiplin says. This allows you to build intensity more naturally and consistently, giving your body a chance to get used to these new physical demands. Once you can run for 30 minutes without walking, start increasing the duration of your runs by 10 per cent each session. (The next one will be 33 minutes and the following 36 minutes and so on). This will help set you up for your first 5K, which will lead to your first 10K, then half marathon.

Running a marathon is a great excuse to get in shape, but starting a marathon training plan shouldn't be your first time working out since Paul Keating was calling the shots. Preparing for an endurance event requires discipline, which isn't something that you suddenly acquire when you register for a race.

The fix: “Take a month to create an exercise routine that you can maintain,” advises Vishal Patel, nutritionist and certified Road Runners Club of America distance coach for sports hydration company Nuun. “Do a 20- to 30-minute workout—anything from spin class to yoga—three times a week,” he says. Previous research in from the European Journal of Social Psychology showed that it takes at least three weeks—sometimes even longer—to pick up a new habit like exercise. Getting into a regular exercise groove also helps you build a cardio base so if you are considering entering a race, you aren’t starting from zero.

Exercise is generally great for your health, unless you have a history of high cholesterol, heart disease, or diabetes, especially if you're over 40, bordering on obese, and a smoker. “Prolonged inactivity may mask the gradual plaque buildup that can develop in your heart,” warns Dr Josh Brown, an internist medicine specialist in Santa Fe, New Mexico, who works with runners. “Abrupt excessive exercise in this situation may lead to lack of oxygen to the heart muscle due to inadequate blood supply (ischemia) and heart damage.”

The Fix: If you have any of the aforementioned risk factors, check with your physician before you start sprinting from your couch at full-speed. When it comes to being overweight, you also want to be careful not to excessively strain your body. “Knees and joints are like the tyres and axles of cars. Put the wrong tyres on a truck and they will wear out quickly,” says Brown. Carrying an extra 20 kilos on your frame is going to make a run hurt, which may deter you from continuing to train. Set yourself up for a positive experience so that you can actually stick with it. “First lose a little with non-weight bearing exercise, like swimming or stationary cycling, and then ease into running,” says Brown. “Get to a point where a 10-minute run doesn't kill your knees. This will help you preserve those tyres.”

You already know getting more shuteye is good for you, but it's especially crucial when you're asking more of your body. “An uptick in exercise creates an uptick in a need for sleep,” Brown confirms. You might be able to get by on limited Z's at first, but running on no sleep will eventually catch up with you, perhaps in the form of an injury since form is often comprised when you're tired.

The Fix: Spend one to three months getting on a healthy, consistent sleep schedule of seven to nine hours a night before you start a training plan. (Going to bed at 10pm and waking up at 5am to run, for example.) “If you can do this, you'll not only be successful, but enjoy the experience a lot more,” Patel says.

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