Pop quiz: You just went for a run. How many kilojoules did you blast? Chances are your guess outpaces reality, to the tune of, say, a Frappuccino. Overestimating kilojoule burn is the Big Daddy of runners’ weight-loss mistakes, says Anthony Meade, sports dietitian at Wakefield Sports Clinic in Adelaide. But it’s not the only misstep. Sneaky slip-ups can derail the weight-loss efforts of even health-savvy runners. Here’s how to avoid eight common mistakes.
OOPS! Miscounting Kilojoules
It’s true that running eats up more kilojoules than nearly any other activity: The average man burns 325 kilojoules per kilometre and the average woman burns 275, which means a 5K nets you a 1300- to 1500-kilojoule deficit. But the longer you’ve been running the more efficient you are and you can easily overspend your kilojoule deficit with something as simple as a flavoured latte and a chocolate-chip biscuit.
Correction: Get a better estimate of your energy burn with an online calculator, like the one at runnersworldmag.com.au/calories-calculator, or with a GPS watch that allows you to input your height, weight and other stats. If you’re prone to overindulging post-run, avoid blowing your kilojoule deficit by finding a couple of “reward” foods with easily controllable portions, like bite-size biscuits or single-serving chips.
OOPS! Skimping on Fat
Feeling virtuous with your dry toast, naked salads, and splash of watery skim milk in your coffee? Not so fast: Your body needs fat to absorb vitamins like A, D, E and K, and to regulate hunger; fats are digested more slowly than carbs and protein, keeping hunger at bay longer. It’s also believed that fat helps your body sense the appetite-regulating hormones ghrelin and leptin, says Meade. A no-fat or very-low-fat diet leaves those hormones out of whack.
Correction: Fat should make up 20 to 30 per cent of your daily kilojoules. But limit saturated fats in processed foods, meat and full fat dairy. Rely on mono- and polyunsaturated fats (olive oil, nuts, seeds, avocados, fish); these protect your heart and promote satiety. A recent study found that even the aroma of some fats, particularly olive oil, may prompt the release of satiety-inducing hormones.
OOPS! Running on Empty
You may have heard this one: Hit the road without breakfast and your body will burn fat. But it doesn’t work the way you’d hope. Rather than seeking out fat preferentially, your muscles always first use carbs that have been stored in your muscles as glycogen particularly when intensity is high. When those stored carbs run low and your body starts to rely more on fat, your energy plummets, forcing you to slow down and burn fewer kilojoules than if you had properly fuelled up.
Correction: If you’re heading out for 30 minutes or less on an easy run, you can skip a pre-run snack, since you probably have enough glycogen to power you. But if you run longer or harder, you should have a 20-30grams carbohydrate snack about an hour before your run. Choose easy options such as a banana or toast with peanut butter, and drink water to hydrate.
OOPS! Not Fuelling Post-Run
After longer or tougher workouts, your muscles have gobbled up all the glycogen they needed, and now they’re hungry. Thing is, you might not be; many runners find their appetite is suppressed just after working out. “But later, when your body settles in and ‘realises’ its glycogen stores are low, you’ll feel much hungrier,” says Meade, leaving you prone to inhaling everything in sight.
Correction: Aim to refuel within an hour of tougher workouts to re-power your muscles and stave off hunger later. Meade recommends a mix of carbs and protein. Aim for 15-20 grams of protein and 30 grams of carbs. With 670 kilojoules per cup, low-fat chocolate milk fits the bill nicely, providing the ideal mix of carbs and protein.
OOPS! GU Overdose
Addicted to mid-run refuelling? You may be piling on more kilojoules than you need by overdependence on energy bars, gels, drinks and shakes. “Kilojoules from mid-race fuels are dense, add up quickly, and usually don’t do much to suppress hunger,” says Meade.
Correction: For runs shorter than 60 minutes, skip the gels and sports drinks; water is fine. Go longer and you should consume 30 to 60 grams of carbs (one or two energy gels or 500 to 1000mL of sports drink) per hour of exercise.
OOPS! Drowning in Kilojoules
Kilojoules in a cup count just as much as those on your plate. Alcohol is particularly sneaky: According to a 2012 report by the Centres for Disease Control, adults consume an average of 420 kilojoules a day from alcohol. Add in sweetened beverages like coffee, tea, soft drink and juice, and you could be overdoing it big-time. Studies show that, in general, liquid carbs don’t contribute to satiety the way solids do. That means if you down 840 kilojoules at the bar, you won’t compensate by eating 840 fewer kilojoules at dinner.
Correction: Most of the liquid you drink should be kilojoule-free: water, mineral water, unsweetened tea. Remember that alcohol may trigger over-eating as your inhibitions drop. “Moderate drinking means one a day for women, two for men,” says Meade. “Cut kilojoules by choosing light beer, wine, or liquor mixed with soda water. Avoid frozen drinks, which are high in sugar.”
OOPS! Rushing Results
Blame overblown weight-loss expectations on celeb-endorsed juice cleanses or reality shows like The Biggest Loser. But trying to change everything at once or reaching for TV-ready results is often overwhelming enough to cause you to abandon your weight-loss plan, says Meade. If you are dropping half to one kilogram per week, that’s a sustainable pace, he says.
Correction: Make small changes, one at a time. Try to eat a healthy breakfast every day, for example. Swap out hot chips for an apple at lunch. It’s not sexy, but it works. Rather than zeroing in on the scales, reward yourself with a manicure or piece of gear as changes morph into habits.
OOPS! Not Re-Evaluating
It’s a physiological fact: Bigger bodies burn more kilojoules, even at rest. That’s why the more you have to lose, the quicker you’ll see weight-loss results. But as you shed kilos and get fitter, your body adjusts and, frustratingly, burns fewer kilojoules (including while running). So what worked initially will need to be tweaked as you slim down.
Correction: Every time you lose 10 to 15 per cent of your weight, re-adjust your daily kilojoule intake, says Meade. Find your new (smaller) needs at sites like runnersworldmag.com.au/calorie-calculator. Recalculate your exercise burn, too, since that also decreases as you slim down.