Turn Up The Burn

The key to lasting weight loss is mastering your metabolism. Here’s how to keep your internal engine speeding along.

Portrait of Tammy Strobel

The key to lasting weight loss is mastering your metabolism. Here’s how to keep your internal engine speeding along.

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You’re working to maintain your healthy new weight. But in order to be successful, there’s one important thing you need to know: Unfortunately, just as your size shrinks after dropping kilos, so does your ability to burn calories. Learning what to expect and how to handle those metabolic changes are what will help you stay slim in the long run, experts say.

As you lose kilos, your body enters what scientists call a starvation state, slowing your metabolism to encourage you to regain weight. In a study at the University of Melbourne in Australia, levels of ghrelin, the hunger hormone, were 20 per cent higher in participants who lost weight, while levels of hormones associated with suppressing hunger were very low.

“The most likely explanation is that this scenario evolved in prehistoric days to protect us from malnutrition,” says study author and endocrinologist Joseph Proietto. “It’s the body’s way of encouraging you to eat.”

Subsequent research has found that these metabolic changes are evident up to three years after weight loss. “We evolved very potent systems to increase fertility and ensure survival back when food was scarce,” explains Dr Michael Rosenbaum, a professor of paediatrics and medicine at Columbia University Medical Center in the US. “Our physiology is designed to preserve fat.”

On average, a person who has had more than a fi ve to 10 per cent drop in her weight requires 300 to 400 fewer calories a day to maintain it than someone who weighs that much naturally, according to Dr. Rosenbaum’s research. “After we lose weight, changes occur in our endocrine, nervous and muscular systems to make us burn fewer calories for the same amount of effort while our brains are telling us to eat more,” he says. Your body may be working against you, but by starting a few new habits, you can reignite your metabolism. Luckily, these changes are easier than you might think.

Get on your feet Standing, stretching and walking throughout the day are crucial to keeping your system revved, according to researchers at the Mayo Clinic in the US. “Every time you get up, your muscles activate and, within 90 seconds, your cellular engines turn on,” says Dr James Levine, a professor of medicine at Mayo and author of Get Up! Why Your Chair is Killing You and What You Can Do About It. Set a timer on your phone or computer to remind yourself to walk around for 10 minutes every hour.

Exercise less but harder Amp up your workouts with high-intensity interval training. A study in the Journal of Applied Physiology showed that women who performed high-intensity intervals on stationary bikes every other day for two weeks burned 36 per cent more fat than they did during a steady cycling workout. “Shorter bursts of intensity can increase mitochondria in the muscles, making it easier for the body to generate energy by metabolising fat for fuel,” explains lead study author Jason Talanian, an assistant physiology professor at Fitchburg State University in the US. On your next run, go fast for four minutes, then take a two-minute break; repeat seven times.

Corbis Water Bottles Radius Images/corbis
Corbis Water Bottles Radius Images/corbis

Time your coffee Downing caffeine an hour before your workout will help you burn 15 per cent more calories afterwards, according to a study in the International Journal of Sports Nutrition and Exercise Metabolism. “Caffeine appears to raise the adrenalin levels in the body,” explains study author Valentin E. Fernandez- Elias, an exercise scientist at the University of Castilla-La Mancha in Spain. This causes you to expend more energy to blast calories, which in turn revs your metabolism.

Get up and get out People who are exposed to bright light from morning to noon have healthier BMIs than those who get more light exposure at other times of a day, research found. Blue light, which is greater in the morning, helps synchronise our circadian rhythms, keeping our appetite in check and our metabolism running. On the fl ip side, “Exposure to light in the evening may alter the hormones that regulate appetite and metabolism so that we eat more and burn fewer calories,” explains Dr Phyllis Zee, director of the Northwestern Medicine Sleep Disorders Center in the US. Natural light is best, so go outside early.

Turn off your brain Stress slows metabolism, a study in Biological Psychiatry revealed. People who ate high-fat meals torched 104 fewer calories when they were feeling tense. “Some data suggests that stress alters the mitochondria in our cells in a way that lowers our metabolic rate,” says Janice Kiecolt-Glaser, director of the Institute for Behavior Medicine Research at Ohio State University in the US. Every day, schedule some downtime to focus on something you enjoy, like taking a bike ride or spending time with friends.

Eat plenty of protein If you don’t get enough of this macronutrient, you’ll be more likely to store any excess calories you eat as fat, according to a study in the American Journal of Clinical Nutrition. “Protein takes more energy for the body to digest than carbohydrates do, so if you eat the proper amount, you’ll burn more of the calories you consume overall,” explains study author Leanne Redman, an associate professor at Pennington Biomedical Research Center at Louisiana State University in the US. Go to www.healthcalculators.org to find out exactly how much protein you need each day.

Drink half a litre of water and you’ll boost your metabolic rate by 30 per cent