1. YOUR METABOLISM IS GOING SLOW

‘Boost your metabolism!’ is a popular weight-loss headline, promising effort-free ways to rev up your body’s calorie burn, but unfortunately it’s not that simple. Research has proven what you have probably noticed: some people just burn calories faster than others. They can pig out with abandon while others only have to look at a muffin to put on 5kg.

The science shows certain factors affecting your metabolism are hard-wired. Gender is one: men’s tendency to have more muscle than women means their metabolism is three to 10 per cent higher, according to research published in the Journal of Clinical Investigation. Age can also work against you, as your basal metabolic rate, or BMR (the number of calories your body burns just to keep your vital organs ticking over), drops between three and five per cent per decade after you turn 18.

You can’t change your genes or age, but there are certain ways you can rev up your metabolic burn. First, get enough sleep: Research published in Proceedings of the National Academy of Sciences found people who didn’t get enough sleep tended to eat more, while other research shows sleeping less than six hours per night means a higher risk of being overweight.

Once you’ve rested, hit the gym: each kilo of muscle burns up to seven calories per day, compared with just two calories burned by one kilo of fat. ‘If you’ve a sluggish metabolism, the best way to make an impact is to increase your muscle mass,’ says nutritionist Kim Larson.

Ingredients such as chilli, cinnamon, caffeine and green tea are associated with boosting metabolism. And research has shown that these foods do have a slight, short-term effect so they are worth adding to your menu. But as the effect on metabolism is minimal, Larson says you’re better off focusing on burning calories through physical activity.

The faster you run, the more calories you burn per minute. This might not boost your BMR, but it will increase calorie burn, even after you’ve stopped running. See number 5 for more on how you can add some speed to your running regime.

2. YOU CRASH (DIET) AND (NO LONGER) BURN

Ever wondered why crash diets don’t work? Part of the problem is that they’re tough to maintain; severe deprivation tends to lead to bingeing. But also, switching to an ultra low-calorie diet actually slows down your metabolism by up to 50 per cent, laying the groundwork for weight gain later on, says Larson. Starved of the calories it needs, the body shifts into survival mode.

RELATED: 6 Basic Ways to Adjust Your Eating Habits for Weight-Loss

The result? You’ll be depriving yourself of calories but still not seeing the scales budge, and you’ll feel depleted even before you run, unable to get the calorie-burning and muscle-building benefits. Even after you return to normal eating habits, your body will still be in survival mode, clinging to as many calories as it can. And because you’ve probably lost muscle, you’ve further hampered your fat-burning capacity.

3. YOU’VE LOST PORTION CONTROL

It’s all too easy to eat too much of the wrong things and outsized portions are a common culprit in sabotaging fat-loss. The single serving packages you buy or create with small zipper-lock bags have been proven to encourage portion control. But when that’s impractical, try the following tips to help you downsize portions.

Look it up: Use calorie-tracking apps and websites to find calorie counts. A calorie counter can help you meet your daily targets and make longer term changes.

Add it up: Don’t rely on memory. Writing down your food intake or recording it in an app will help you stay on track. Seeing you’re near your daily target encourages you to hold off on dessert.

Measure it: Use measuring spoons and food scales to measure out the serving sizes on the nutrition information label. Portions are smaller than you think.

Visualise it: If you don’t have such measuring devices to hand, here are some cues to understanding common portions.

• A typical 85g serving of meat or fish should be about the size of the average smartphone.
• A typical 180g serving of whole grains such as rice or quinoa is about the size of a cricket ball.
• One medium piece of fruit, such as an apple or orange, should be about the same size as a tennis ball.
• A typical 2 tbsp serving of peanut butter or any other nut butter should be about the size of a golf ball.

4. YOU DON’T READ THE LABELS

Studies have shown that people who read food labels are more likely to lose fat. When left to our own devices, we vastly underestimate calorie counts. But deciphering those labels isn’t always easy. Use this guide to what you should look for to help you slim down (and speed up).

Serving size: Many serving sizes are much smaller than those people are accustomed to eating.

Number of servings: Some foods that look like a single serving are actually two, or more.

Calories per serving: Assess this in terms of your daily target

Saturated fat per serving: High levels raise heart disease risk. The Department of Health recommends saturated fat should account for no more than 11 per cent of your energy intake.

Trans fats per serving: Found in processed foods and usually listed as hydrogenated or partially hydrogenated vegetable oil, trans fats have virtually no nutritional value.

RELATED: How To Get Started If You’ve Got More Than 25kg To Lose

Sugar per serving: For refined sugar aim as low as possible, though if you’re eating raw fruit or dairy products, don’t stress about the sugars.

Protein per serving: Aim high, while maintaining your calorie target. Protein keeps you full, and repairs and rebuilds muscle. Spread intake through the day and beware ‘high-protein’ foods: some bars have a meal’s worth of protein, but also a meal’s worth of calories.

RELATED: 4 Reasons You Should Eat Protein At Breakfast

Fibre per serving: Like protein, fibre makes you feel full. It also keeps your GI tract healthy. It can reduce cholesterol levels, so it promotes heart health.

Vitamins and minerals: The best foods are nutrient dense, which means that in addition to a good blend of carbs, fats, and protein, they contain key vitamins and minerals such as calcium, vitamin C and iron. Look at the ‘recommended daily allowance’ column to judge levels.

Ingredients list: Remember, food ingredients are listed in descending order of weight. So if sugar is first…

5. YOU’RE DOING THE SAME OLD

We runners love routine. When we start out, the familiarity of running the same route at the same speed and at the same time, every time, helps us exercise consistently so we can continue building our fitness and work toward our fat-loss goals. But there’s a fine line between a routine that grounds you and a rut that grinds you down, leaving you stuck on a fat-loss plateau or, even worse, starting to gain fat instead of losing it, despite your diligence. Remember, your body will adapt to any new stress you put on it, so the key to continued fat loss is adding intensity to your running routine. Study after study proves that when you ratchet up the intensity, you torch more calories on the road and even after you’ve finished your run.

Related: 12 ways to get out of a running rut

Adding tempo runs, interval sessions and hill runs will provide new stimulus and keep powering your fat loss, but this is not without its risks. As you ratchet up the intensity, the following steps will help you make the most of your valuable run time without developing an injury.

Pace yourself: Make sure you’re doing your harder workouts at the right pace for your fitness level. To find your 5K or 10K pace, plug a recent race time into our training pace calculator. Don’t have a recent race time? Do a time trial: warm up with one kilometre of easy running, then run one kilometre as fast as you can and plug your time into the training calculator to get your training paces.

Don’t cram: People get hung up on running a certain number of kays per week and, if they miss a session, try to cram in the extra kays. That’s a recipe for injury. When life gets in the way – or you simply feel fatigued or sore – it’s OK to postpone or cancel the run. But if you try to cram in kays in too short a period, you could get sidelined by injury for weeks or months.

Stay well fuelled: When you’re running faster and going longer, make sure you’re well hydrated and fuelled before you go out. If you’re energised, you’ll run faster (and burn more calories).

RELATED: 16 Healthy (and Yummy) Prerun Meals and Snacks

Don’t discount life stress: Studies have shown that workouts feel tougher for people who are stressed than for those who aren’t, even when they are working at the same effort level.

6. YOU’RE OUT OF ACTION

It happens to us all, usually when we least expect it. Our exercise and fat-loss efforts are humming along when, suddenly, something – injury, work, family – sidelines us. When your running gets derailed, it can be easy to pack on the kilos. Some people keep up the eating routines that fuel their running even though they’re not lacing up. For others, the absence of the stress release that running provides leaves them more vulnerable to the call of junk food. But weight gain when you can’t run doesn’t have to be a foregone conclusion. Here’s how to prevent the number on the scales from going up while your mileage goes down.

RELATED: 12 Strength Tips for New Runners

Identify the culprit: When not running you need to be extra vigilant about calorie intake. Where are your extra calories coming from? Have your portions grown too large? Are you mindlessly snacking in front of the TV? Be honest with yourself. It may be humbling, but to get back on track you need to face the truth about what you’re consuming.

Stop emotional eating: Consider when you might be snacking simply to relieve boredom, stress, restlessness or other uncomfortable emotions. List calorie-free strategies you can use to relieve those feelings. Studies show that waiting as little as two minutes is enough to make the craving dissipate.

Keep moving: If you can still exercise – even at lower intensity – do it at the same time of day you’d usually run, so you get the comfort from your routine and some calorie burn. If you can’t work out, try to incorporate more activity whenever you can. Get up from your desk and walk to the water dispenser, take the stairs instead of the lift. These extra minutes of moving add up, and every calorie burned helps.

Seek the benefits elsewhere: Remember that running provides a daily biochemical reset as well as a calorie burn. Studies have proven that 30 minutes of physical exercise can help inoculates you against stress. Exercise can also provide social time, and just a few easy kays are enough to give you a powerful sense of accomplishment. If you’re facing time when you can’t run, make a list of the benefits running provides, and work out how you could reap similar benefits. Meet friends on Saturday mornings when you’d usually join a group run, or use that time for some other reflective practice that’ll relieve stress.

Plan ahead: It’s hard to make healthy choices when you walk though the door, still shouldering the stresses of the day. By planning ahead you’ll increase the chances of eating right. Try mapping out the week’s dinners on Sunday evening. Do some of the preparation ahead of time so dinner is ready within minutes of getting home – and you won’t give in to crisps and biscuits.

Address your weaknesses: Use the time off to strengthen areas of fitness where you might be weak. It’s a good time to start a strength-training programme, or start a routine of cross-training or massage.

7. YOU DON’T HIT THE GYM

Research proves weight training, when combined with running, can boost your calorie burn more than running alone.

RELATED: Best Gym Classes For Runners

Do these 10 strength moves back to back, performing each move for one minute, with 15 seconds’ rest before moving to the next. Repeat the sequence two or three times per week for three to four weeks. As you gain strength, ratchet up the intensity of the programme so you keep improving. When you’re ready, do the circuit in reverse. After three more weeks, change it up again by performing all the lower-body exercises consecutively, followed by the upper-body moves, then finishing up with the core work.

8. YOU’RE HARD ON YOURSELF

Give yourself a break: research published in the Journal of Social and Clinical Psychology found that after indulging in a doughnut, dieters with ‘self-compassion’ could hold back on further eating better than those who focused on the negative implications of their indulgence. If, after an off-the-diet biscuit, you’re filled with feelings of hopelessness, self-hatred and regret, chances are you’ll resign yourself to failure and finish the packet.

But if you imagine you’re counselling a friend who has just eaten that biscuit, you’d be more likely to assure them one biscuit won’t ruin a diet. Look at your food diary: you’ll see that 99 per cent of the time you’re doing great, then you can start again. The same goes for running. If you hit the wall before finishing a run and have to shuffle home, the demoralisation can be paralysing, but if you look at your log and see how many miles you’ve covered, or days you’ve run, you’ll see that one bad day is no big deal.

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