9 Science-Backed Tips for Changing Your Body Composition

These nine simple nutrition and training tips could make or break your body-composition goals.

Photo: GettyImages

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As you probably know, there’s a vast difference between losing weight and losing body fat — aka getting lean. Keeping your body fat in check isn’t just about physical appearances, but the long-term benefits of being lean and mean include a reduced risk of heart disease and diabetes and the prevention of certain types of cancer.

Unfortunately, leaning out takes more than the magic potion of willpower, luck and genetics — it also requires some trial and error and a whole lot of consistency. These science-based tips offer some concrete action items to help point you in the right direction and set you on a course toward accelerated fat loss.


Junk Food
(Photo: GettyImages)

1. Don’t Trust the Process(ed)

A study published in Cell Metabolism revealed that those eating an ultra-processed diet consumed an average of 500 more calories per day and gained 2 pounds in just 14 days, while those eating a diet of unprocessed foods lost 2 pounds. Those on the ultra-processed diet also ate much faster, a habit that can lead to overeating because your gastrointestinal tract doesn’t have enough time to tell your brain when you’re full.

“Packaged, ultra-processed, high-calorie, low-nutrient foods contribute to weight gain and make it harder to lean out,” says Wendy Bazilian, DrPH, RDN. This might sound obvious, but even the most dedicated clean eaters succumb to the wiles of the cookie aisle now and again.

Prevent a snaccident by shopping the perimeter of the grocery store. This is where you’ll find whole-food options like vegetables, fruits, protein and dairy, while the packaged, processed items are found mostly in the center aisles. If you do happen to wander into the middle, look high or low on the shelves for better packaged options: Eye-level shelf space costs more to purchase, and a big-box manufacturer that creates lower-quality foods has deeper pockets than a mom-and-pop company that makes more wholesome items.

2. Secretly Sensitive

Do certain foods make you feel bloated, headachy or fatigued? You might have a food intolerance. “With a food intolerance or sensitivity, your body is identifying a food as foreign and spends time and effort ‘attacking’ it,” says Maggie Berghoff, MSN, FNP-C, functional medicine nurse practitioner. “When your body is focused on attacking these foods, it’s spending energy [doing that] rather than using it to build lean muscle and burn fat.” Besides squelching your fat-loss efforts, a food intolerance can lead to inflammation, swelling, rashes and headaches.

More than 20 percent of the population suffers from a food intolerance or allergy, and many of those don’t even know it. “The annoying part is that a food intolerance can be anything, really,” Berghoff says. “For you it might be olives, for me it could be lemons or corn.” In other words, sugar, gluten and nuts aren’t the only dodgy items to be aware of. If you suspect a food doesn’t agree with you, eliminate it for a few weeks and see how you feel. If you add it back in and your symptoms return, you might be allergic or intolerant.

According to the Obesity Society, an inflammatory diet is associated with greater annual weight gain and a higher risk for developing obesity.

Eating late at night
(Photo: GettyImages)

3. No More Midnight Snacks

Research published in the Annals of Internal Medicine found that a lack of sufficient sleep may promote the retention of body fat, and another study found that women who sleep five or fewer hours are at greater risk for weight gain. Why? Evidence indicates that a lack of sleep leads to reduced levels of the satiety-promoting hormone leptin and increased levels of the appetite-promoting hormone ghrelin, thereby compromising the efficacy of a weight-loss program. Bottom line: There’s a definitive relationship between establishing sound sleeping practices and weight control, so do everything in your power to get those zzz’s.

First order of fat-loss business: Eliminate all late-night noshing. “Your body needs time to digest prior to sleeping because it takes a lot of energy to break down, digest, absorb and eliminate foods,” says Berghoff, adding that eating less than three hours before bed may reduce your sleep quality and cause noticeable daytime deficiencies in energy and focus. “At night, we want the body to focus on getting restorative and restful deep sleep, not breaking down your dinner.” Plan your mealtimes accordingly to optimize your sleep and digestion schedules.

4. Fork Up Fiber

A study in Nutrition Today revealed that a Western-style diet, which is high in fat and refined carbs and low in fiber, may promote an increase in the strain of intestinal bacteria linked to obesity. “Fiber-rich foods are natural prebiotics that feed the good bacteria in your gut, which play a role in your weight,” says Kristin Oja, DNP, certified functional medicine provider and founder of STAT Wellness in Atlanta. “Most people on a Western diet only consume about 10 to 15 grams of fiber, which can disrupt a healthy gut microbiome. In addition, a diet high in processed sugar feeds the bad bacteria and yeast in your gut.”

To improve gut health and optimize your fat-loss efforts, Oja recommends consuming at least 30 grams of fiber per day by choosing fiber-rich whole foods, such as avocados, raspberries, artichokes, chickpeas and lentils.


(Photo: GettyImages)

5. Find Your Fitness Level

Tabatas, metcons, endurance training — there are endless ways to exercise these days, but which protocol is right for you? The answer depends on your current level of fitness. Those who are new to exercise or who have a lot of weight and fat to lose should focus on aerobic exercise: A study in the Journal of Applied Physiology showed that while strength training increases muscle mass and overall strength, aerobic training was more effective for the overall reduction in body mass and fat in sedentary, overweight or obese adults. “If you are coming from a place of zero exercise, start with steady-state cardio three to four times a week,” says yoga instructor Stephanie Mansour, AFAA-CPT. Once your body acclimates to this new activity level, you can add in some strength training and increase the duration and intensity of your cardio.

On the other hand, if you have less weight to lose and/or have been doing both cardio and strength training for a while, more intense workout programming such as high-intensity interval training will better boost your fat burn: Research done at the Mayo Clinic found that three HIIT sessions per week for 12 weeks resulted in more body fat lost and more muscle gained than the same amount of training at a moderate level.

6. Give It a Rest (Really)

When it comes to exercise, more is not always better, and an overzealous training regimen could deliver the opposite of your intended and desired results. According to research published in the Open Access Journal of Sports Medicine, overtraining has a negative physical impact on your body and can lead to injury, fatigue and reduced strength. But it also can cause changes in mood (depression), decreased immunity and heightened cortisol. “When your immune system is weakened or your cortisol is elevated or if you are depressed, weight loss can be compromised,” Mansour says. “If you are having a difficult time losing weight or leaning out, consider adding more rest days to your programming or reducing your workout intensity for a while.”

Have a look at your training schedule and see where you can cut back on the duration or intensity of your workouts. Add in one or two more days of complete rest for two to four weeks, then reassess your mental and physical progress.

7. Space Case

Making simple adjustments to your overall training calendar can optimize your fat-loss efforts: Research published in Frontiers in Physiology found that two consecutive days of extreme conditioning training resulted in a decreased immune system response. In other words, because most of your energy is dedicated to repairing your muscles and healing your body after super-hard training, you have very little left for immune support. “Then your body is working to fight off bacterial infections and viruses [without adequate immune support], and it is challenging for it to also focus on fat burn,” Mansour says.

Ensure there is plenty of recovery time between your most intense training sessions — between 48 and 72 hours is recommended by experts — and space them out by scheduling in low-intensity workouts and days of complete rest.

8. Be Mental About Your Training

Be honest — are you phoning in your workouts? A lackluster showing at the gym won’t get you closer to your goals.

“One of the single greatest determining factors to attaining more lean muscle mass is mental intensity,” says Alain Saint-Dic, NASM-CPT, head of development and training at Stretch Relief. “Mental intensity comes down to mindset, intent and focus, knowing your overall plan, being diligent toward getting it done at your highest capacity … and remaining fully engaged. And while these things are rooted in psychological elements, they can also be quantified based on the type of brain wave you emit during your workout: If you’re at a higher level of intensity and focus, chances are you’ll be emitting more high-frequency brain waves, which denote that increased focus, attention and intensity.”

It stands to reason, then, that if increased intensity equals higher-frequency brain waves and if higher intensity equals increased fat loss, then higher-frequency brain waves equal increased fat loss — though while logical, Saint-Dic emphasizes that this idea is purely theoretical.

“If your training is intense enough to [create] the psychological demand of being ridiculously dialed in, hence producing that higher-frequency brain wave, that is also a sign that you’re likely losing more fat,” he reasons. Studies have shown that high-intensity interval training produces a significantly greater reduction in fat mass than lower- or moderate-intensity training, Saint-Dic adds.

To game your brain, go into each training session with a laser-like focus and intention. Put aside anything that can distract you from your purpose — smartphones included — and dedicate that single hour to 100 percent intensity and pushing your limits.

9. Do Moves That Spark Joy

Just as you can Kondo your living spaces, so can you unclutter your exercise regimen. And while this is not an excuse to avoid burpees for the rest of your life, your workouts should be enjoyable in order to be effective. “If you are able to have fun with a workout, you are more likely to want to do it again, which, in the long run, results in positive training outcomes,” Berghoff says.

On the subject of happiness, research published in the Irish Journal of Medical Science suggests that exercise and physical activity are beneficial in the treatment of depression and that the effects of a workout regimen are comparable to results gained from the use of antidepressant drugs. “This is because [exercise] releases positive ‘feel-good’ endorphins that elevate your mood and [activate] important neurotransmitters in the brain that help with your mood regulation and happiness,” Berghoff says.

Here’s where the cause and effect come together: The happier you are doing something, the more likely you are to continue doing it — and consistency is key to success in most workout programs. The same applies to negative feelings, and if you are unhappy and unable to enjoy your training plan, Berghoff says, this may very easily result in halted weight-loss efforts or even additional weight gain.

Take a step back from your current workout programming and decide whether you love it — regardless of its promised results — because if Orangetheory is not your jam and you’d rather be running in the mountains, then invest in a solid set of trail runners instead of dishing out membership dues for a protocol you don’t enjoy.