There are ways to overcome hormone shifts and metabolism dips to shrink ab fat. Just follow this expert guide to getting your best belly in your 20s, 30s, and 40s.

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There are ways to overcome hormone shifts and metabolism dips to shrink ab fat. Just follow this expert guide to getting your best belly in your 20s, 30s, and 40s.
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In theory, these should be flat-ab glory years. Though your metabolism starts to drop by 1 to 2 per cent when you cross from your teens into your 20s (that means, if you’re burning 2,500 calories a day in your teens, you’ll burn 25 to 50 fewer calories a day in your 20s, which is why most people gain an average of 0.5kg per year at this age), it’s still high, says endocrinologist Dr Scott Isaacs, author of Hormonal Balance: How to Lose Weight by Understanding Your Hormones and Metabolism .

You’re also continuing to churn out large amounts of hormones, like oestrogen, which peaks in your late teens or early 20s. It guides your body to store fat in the hips, butt, and breasts instead of the midsection, and the human growth hormone releases fat from its stores in the body so it can be delivered to your muscles for energy, Dr Isaacs says.

Still, even with all this in your favour, four years of late nights may have left you with a post -grad gut, and those poor eating and drinking habits have a tendency to linger. “After graduation, people tend to spend more time sitting at a desk, and this sedentary lifestyle can lead to more weight gain, especially if you’re still drinking a lot and not keeping close tabs on your diet,” Dr Isaacs explains.

This is particularly true if you consume a lot of carbs. A recent study in the Journal of Nutrition revealed that large amounts of processed carbs (the higher-carb participants in the study were eating 55 per cent carbs, 18 per cent protein, and 27 per cent fat) raise the body’s level of insulin, which prevents fat from being unlocked from abdominal fat stores and burned off.

Another factor: “Many 20-somethings haven’t hit their fitness stride yet; they’re doing too much steady-state cardio and not enough strength training and cranking out old-school crunches, a particularly ineff ective combination for chipping away at belly fat,” says Holly Perkins, a strength and conditioning specialist and author of Women’s Health Lift to Get Lean: A Beginner’s Guide to Fitness & Strength Training in 3 Simple Steps.

FLAT-AB FIX Start by shifting your eating habits away from carbo loading. “Help keep insulin at a healthy level by following a moderate carb diet, in which most of your carbs come from nutritious unprocessed sources like whole grains, beans, fruits, and vegetables,” says nutritionist Lisa Young, author of The Portion Teller Plan: The No-Diet Reality Guide to Eating, Cheating, and Losing Weight Permanently.

The participants in the Journal of Nutrition study, who were given a moderately low-carb diet (43 per cent carbs, 18 per cent protein, and 39 per cent fat), lost 11 per cent of their abdominal fat after eight weeks, compared with those on a low-fat, higher-carb diet, who lost only 1 per cent ab fat.

And because the goal is to burn flab, you need to choose calorie-incinerating workouts. “It’s important to incorporate steady-state cardio, interval training, and strength training,” Holly says.

She recommends doing two 35- to 40-minute steady-state cardio sessions a week at a pace that’s about a seven out of 10 on the intensity scale; two 30-minute interval workouts (go for two minutes at moderate intensity followed by two minutes at an almost-all-out pace) to maximise growth-hormone secretion and fat burning; and two days of strength training to build lean muscle mass, which ups your calorie burn.

Any type of strength training will be effective, as long as the programme gets progressively harder (more weight, more reps) so that you continue to challenge your body. If you’re not up for sweating six days a week, you can double up and do the strength training on your cardio or interval days.

“Twenty-somethings still have metabolism and hormones on their side, so they just need to develop a definitive fitness strategy that includes a balance of cardio and strength training to kickstart their burn and firm,” Holly says.
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For many women, their 30s are the time to have babies. Pregnancy can cause your rectus abdominis muscles (six-pack muscles) to stretch to the point of separation, a painless condition called diastasis recti, which Brazilian researchers found affected 68 per cent of women above the belly button and 32 per cent below, when measured at up to eight weeks postpartum.

“The muscles usually move back together on their own,” says Dr Mary Minkin, a clinical professor of obstetrics, gynaecology, and reproductive sciences at the Yale School of Medicine. “In extreme cases, surgery may be needed to repair the separation.” Otherwise, you’re probably just dealing with some leftover fat and ab muscles that became stretched out during pregnancy.

That doesn’t mean they can’t snap right back, but it takes some effort. Luckily, you still have a respectable metabolism in your 30s. While it drops another 1 to 2 per cent from the first small dip in your 20s during this decade, that’s not really going to catch up to you for another decade or so. Oestrogen levels can start to drop for some women in the late 30s as fertility diminishes, but less oestrogen isn’t an issue until you are well into your 40s. And you can still cash in on your growth hormone production for now, too. FLAT-AB FIX Getting your pre-baby belly back requires a two-pronged approach. You need to melt the flab covering your abs and strengthen your stretched-out muscles. Trainer Sara Haley, creator of the Expecting More pre- and postnatal exercise DVD programmes, suggests the following time-saving high-intensity routine, which has you moving fast enough to keep your heart rate up to torch calories and incorporates moves designed to tone and tighten your whole core; these exercises are safe for those with diastasis recti, as long as it’s not severe.

After warming up, do each of the following moves for one minute: high knees (run in place), plank squats (start in a plank, then jump feet forward and pop up into a squat), knee repeaters (get into a low lunge, clasp hands over your head, and bring your back knee up to your chest while simultaneously bringing your hands down to meet the knee; do one minute per leg), and dead bugs (lie face up on the floor with your legs raised, knees bent at a 90-degree angle, arms raised towards the ceiling, and flex your feet as if you’re pushing something away with them while focusing on pulling your belly button into your spine).

Rest for one minute, repeat the circuit twice more, and cool down. As much as you may want to throw a crunch into the bunch, don’t. Crunching and twisting movements can make any separation worse because they repeatedly open and close the abdominal muscles, Sara says.

And while juggling work, kids, and a relationship don’t leave a lot of time for slumber, make sure you get as much shut-eye as you can (shoot for seven to nine hours per night) because sleep deprivation jacks your level of the stress hormone cortisol, which encourages ab-fat storage.

If the kids keep you up at night, a Pennsylvania State University study found that a two-hour afternoon nap can off set the effect that a bad night’s sleep can have on cortisol. “Even a short nap – if only for a half hour – may have a small beneficial effect,” Dr Isaacs says.
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Trade some steady cardio for a few HIIT sessions to burn ab fat, plus lift and plank to keep it tight.

The levels of sex hormones, including oestrogen, begin to dip at this age. “Until now, the oestrogen receptors’ influence on fat deposition in the breasts, hips, and butt have been more powerful than the receptors controlling how much fat is stored inside and outside the abs.

As oestrogen declines in your 40s, the receptors in the abdomen begin to exert more power, so you start to preferentially gain weight there,” says Dr Pamela Peeke, author of Fight Fat After Forty: The Revolutionary ThreePronged Approach That Will Break Your Stress-Fat Cycle and Make You Healthy, Fit, and Trim for Life.

Not only does the metabolism drop by another 1 to 2 per cent from when you were in your 30s – one study found that people can lose as much as 8 per cent of their calorie-burning muscle mass from age 40 to 50 if they haven’t been taking preventive steps – but the growth hormone also dwindles. In fact, one University of Virginia study found that there’s about half as much at 45 as there is at 25. FLAT-AB FIX There’s not much you can do on your own about the loss of oestrogen, but a sure-fire way to boost the growth hormone is to go hard at the gym. “Moderate- to high-intensity programmes with multiple sets, high reps, short rest intervals, and exercises that target multiple large muscle groups at one time produce substantial acute growth hormone responses,” says Nicholas Ratamess, a professor of health and exercise science at the College of New Jersey, who suggests working out intensely at least three times a week for 30 minutes.

A review of research in the Journal of Applied Physiology found that in 25to 43-year-old women, regular highintensity aerobic exercise resulted in a twofold increase of growth hormone release over 24 hours.

As for muscle loss, it’s somewhat preventable. “If you’re staying physically active and lifting weights, you should be holding on to about the same muscle mass you had in your 30s,” Dr Peeke says. Research in The Physician and Sportsmedicine suggests that cardio can also be effective at helping you pack on muscle or maintain it.

The study found that intense aerobic exercise (running, biking, or swimming four to five times a week) reduced muscle loss in athletes aged 40 and up as regular exercise stimulates protein synthesis (repair and maintenance of muscle) and boosts muscle mass and strength. You can also help build and maintain muscle mass by eating 50 to 60g of high-quality protein a day; a nice mix of sources could include a cup of cottage cheese, Greek yogurt, legumes, and a piece of fi sh or chicken.

Finally, no need to get discouraged: Keep in mind that you can start reversing age-related ab issues at any time in life. “If you exercised in your 20s and 30s, your 40s will be a breeze,” Dr Peeke says. “The great news is that you can start in your 40s and start seeing long-lasting results – it’s never too late.”