The Best Exercise to Lose Weight (and Keep It Off)

Have you heard the cliche that “abs are made in the kitchen”? Or that weight loss is “80% nutrition”?

While there’s certainly a kernel of truth to truisms like these, I know as a personal trainer – and as someone who has lost weight and kept it off – that dieting is far from the whole story when it comes to long-term fat loss.

Many of my readers know that 12 years ago, I lost about 50 pounds. At the time (in my 20’s), I shed the weight gently with a combination of dietary changes, walking, and light yoga and strength training. Without “living at the gym” or doing anything heroic, I had the sensation of the weight simply melting off. Long story short, within a year, I went from being over 160 pounds (at 5’4″) to stepping on the scale and seeing 112.

That experience sparked my interest in health and fitness. It also led me to switch careers from teaching to personal training, and laid the foundation for my coaching career focus on habit sustainability and gentle approaches to weight loss. For years, weight maintenance was easy.

But when I had my daughter in my 30’s, the weight didn’t exactly… melt off.

I gained a healthy, average amount of weight during pregnancy, lost a large amount of weight very quickly postpartum, but then could not get the stubborn last 10-ish pounds to budge even one bit. Instead of dropping back to about 120-125 (which was where I settled after my initial weight loss over a decade ago), I hovered frustratingly around 130. Even with prolonged and aggressive dieting attempts, my weight would drop to about 127-128, then creep back up to 130, and then go even higher!

It was maddening. I felt like one of my perimenopause or menopause clients, where the weight just won’t shift despite your best and hardest dieting attempts. Or if you do lose weight, you feel like you can’t keep going with the caloric deficit, because it’s so challenging to maintain.

Despite the fact that I had all the know-how in the world (this was my specialty, after all), it didn’t click for me that I was doing exactly what I told my clients not to do – I was trying to shrink my diet to fit my metabolism. In the process, I was shrinking my metabolism, too, from wave after wave of dieting attempts.

And it makes sense. When you have a small child, you don’t have an abundance of time to yourself. As a working mom and business owner (and as someone who had just bought a house),  it was easier for me to cut calories than it was to “make time” for exercise. To be clear, I was exercising, but my strength training consistency and organization had radically decreased.

And as I share with clients, when your stress levels are high and you’re dealing with scarcity issues (including time scarcity), you’re also vulnerable to tunnel vision (check out this life-changing podcast episode of “Hidden Brain” to learn more about this).

Even though I had expertise, at first I couldn’t see that I was digging myself deeper and deeper into the hole. 

But once this clicked, I realized that I needed to reverse my efforts and invest my energy back into building up my metabolic output, instead of the other way around. And this is what I did… and I lost the weight.

To understand this, and how it can work for you, we need to talk about metabolism.

How Metabolism Works

Metabolism is a complex function of the human body, but it’s basically how much energy (calories) you burn both at rest and doing things. Everything takes energy. Digestion takes energy. Muscles contracting takes energy. Even thinking takes energy – your brain burns more calories when you are performing difficult cognitive tasks!

We burn energy doing nothing (basal metabolic rate, or BMR), and then there’s the total energy we burn through living + physical activity (total daily energy expenditure, or TDEE). There are other aspects of metabolism, too, but let’s keep it simple.

Muscle is a very metabolically active tissue – meaning, muscle burns a lot of calories, especially during workouts, but even at rest. The fancy term for it is that muscle is “metabolically expensive” – it requires a lot of energy (calories) for your body to build and maintain muscle. On the positive side, this means that if you have a lot of lean body mass (muscle), your metabolism will be higher and faster. But on the flip side, your body will also happily break down and burn muscle for energy if it can, because it wants to offload the “expense” of maintaining it. Think about times when you’ve reviews your spending budget and have cut out a few TV and app subscriptions you never use. Muscle is the same way – your body will slice it from the metabolic budget when it’s not being used, because it’s expensive.

Because of this, when people lose weight, a huge percentage of their weight loss can come from muscle if they are not strength training. Unfortunately, this disproportionately decreases the person’s metabolic rate. This is especially true for women, because we tend to be smaller anyway, and even more so for women over 35, because of hormonal shifts that make it harder to build and maintain muscle.

Building Yourself a Bigger Metabolism

Many of my clients are more petite women (under 5’4″) because weight loss is, honestly, often harder for shorter people. A smaller body often has a lower metabolic output, because it’s not as much “machine” to maintain as a larger body. The muscles are smaller, there is less blood volume, the organs are smaller… it just takes a lot less fuel to run it. So for some women, especially closer to the 5′ mark, calories have to get so extremely low for weight loss to happen that it’s practically unlivable. On the flip side, a very petite woman can be very overweight and not be eating that much. For many of my clients, it may only take 1600-1800 calories to maintain their current bodyweight… and if you know anything about nutrition, 1600-1800 calories is not a lot of food.

So if you have to eat 1100-1300 calories a day to lose weight, you are not living normally in terms of societal food rhythms – it’s incredibly restrictive, and diet has to be top of mind all the time to stay consistent.

Even if you’re not very petite, you may experience this if you live with a male partner. Because men have more lean body mass and are generally larger than women, their metabolic output tends to be more robust. If you’re like me (my husband is a foot taller than me), the contrast in calorie needs can be really pronounced.

This is obviously a big problem for weight loss. It creates issues of sustainability – how long can you maintain a diet if it puts you out of step with everyone around you? With co-workers? With family? With societal eating norms?

So what happened to me when I was aggressively dieting in pursuit of the “last 10 pounds” was classic, textbook metabolic self-sabotage. Every time I lost a few pounds, I was losing some of my metabolic edge, too, by losing muscle (I wasn’t strength training consistently, remember?). I would end each dieting attempt a few pounds lighter but with my body fat percentage a little higher than it was the last time I lost weight, and my metabolism was a few hundred calories slower, too.

This made weight re-gain so frustratingly easy and fast.

Change did not happen for me until I got serious about my strength training again, so that I was building a body with a bigger metabolism, instead of trying to shrink everything down smaller and smaller.

Once my muscle mass was higher and my metabolic output was better, I could eat “normally” and wasn’t restricted to a 1000-1300 calorie diet anymore.

Do you want to do this for yourself, too? Are you stuck in this cycle of minor weight loss followed by easy weight re-gain? Do you feel like you have to diet very hard to lose weight?

Let’s talk about building up your metabolism through strength training. 

Hit the Weights!

Remember, you don’t just want to lose weight – your goal is to build yourself a bigger metabolism, too. And the way you do that is through exercise – especially strength training.

Your body will not lose muscle (or not as much) if you are doing solid strength training, at least several times a week. Even if you are losing weight, your body will prioritize holding onto muscle because it senses that you need it for your lifestyle. This helps your overall metabolism (even your BMR) to stay a little higher. And every little bit counts!

Although sometimes it’s easy to feel like your body are working against you, the truth is that your body is smart. It likes to stay in equilibrium, and it will adapt to the signals that it’s receiving. If it’s getting the message that you lift and move around heavy things several times a week, it will build and keep muscle instead of burning it off for energy.

What kind of strength training should you do to trigger this process?

  • Use heavier weights 
  • Use “bigger,” full body lifts (like squats, deadlifts, push-ups, bench presses, lunges, etc.)
  • Do it 2-5 times a week 

You need stress on the muscles every few days for your body to get the message. For many of my clients, I love a 3-day full body workout schedule. For some of my clients who are extremely consistent with strength training (especially if they have access to a gym), I program 4-day splits of upper-body and lower-body workouts.

It’s important that the weights aren’t too light because the muscle-building switch “flips on” when your body senses the mechanical tension from the weight itself. If you’re a total beginner, it’s totally fine to start with bodyweight exercises and light weights – you probably need to work on the movement patterns and groove those neural pathways. But once you’re familiar with the movements of squatting, deadlifting, lunging, pressing, rowing, etc., it’s time to add enough weight that your muscles feel the stress of the movement, and it’s hard to do more than 8-10 reps of an exercise.

Remember, your body is very smart and adaptable. If you don’t challenge it with strength training, your body will “burn” muscle for energy because it doesn’t sense that it needs to keep the muscle. But if you give yourself the hard work of strength training several times a week, your body will get the signal that it needs more muscle and strength to cope with the physical demands of your lifestyle, and you will build and keep muscle and therefore have a bigger, faster metabolism.

I have so many clients who come to me in their 40’s and 50’s having never incorporated strength training consistently into their exercise. Maybe they’ve done other forms of muscle-strengthening exercise like Pilates or yoga, but they’ve never gone down the path of “progressive overload” (a weightlifting term meaning that you increase the weight over time). The miracle is that their bodies transform.

Currently, my 58-year-old client Julie is experiencing this. She has done Weight Watchers probably dozens of times, but has always struggled with weight regain. Her goal this year was to get to 150 pounds and stay there, but just this week she hit 146 pounds and is still going down. Strength training opens up a whole new door of body transformation that was never possible before, especially if you’re over 35. 

Here are a few things to keep in mind, however, when you start your strength training journey:

  • Strength training and step count are a potent combination. You can’t expect to do a 20-minute home workout and see radical change – hitting 7,000-8,000+ steps per day will push your results over the edge, though. Experiment with finding a good balance between exercise exertion and regular physical activity. The goal is to disrupt sitting time, too – not just to kill it in the gym.
  • Protein also plays a powerful supporting role in giving your body the hormonal signal to build and maintain muscle – I’ve written another article about it here. Elevating your protein intake is one of the most important dietary changes you can make.
  • You’re playing the long game, because exercise seems to be the most important lifestyle factor in keeping weight off once it’s lost. The National Weight Control Registry, which tracks people (via yearly surveys) who have lost weight and kept it off, reports that most people on the NWCR exercise about an hour per day. Nutrition will give you an edge with weight loss, but robust exercise habits will help you keep it off.


  • Reject the cliches that “abs are made in the kitchen” – get in the gym!
  • Especially if you are a woman over 35, be careful about aggressive dieting (super low calories)
  • Focus on strength training 2-5 times a week with heavier weights and challenging workouts
  • Get your steps up – 7,000-8,000+ is a fantastic target
  • Be mindful of not decreasing steps as a result of intense exercise – you still need the steps!
  • Eat more protein with every meal (especially the ones that tend to be low-protein for you… breakfast is a common culprit)
  • This combination of lifestyle changes will give you a bigger, better metabolism, which allows you to eat more flexibly and have more sustainability in your approach

Need Help?

Want to talk over your lifestyle in real-time? Reach out for a free 30-minute consultation – I’m happy to listen.

Rachel Trotta

I am a Certified Personal Trainer, Fitness Nutrition Specialist, Physique and Bodybuilding Specialist, and Women's Fitness Specialist. I live in New Jersey in the NYC metro area, and I coach clients online all over the world. As a trainer and health writer, my mission is to make healthy living sustainable for the average person. I’m also a wife, mom, nature lover, runner, avid cook, weightlifting aficionado, history nerd, travel addict, and obsessive podcast listener. Get in touch!

Free Download

Get My Free 28-Day Meal Prep Guide