Does The Type of Exercise You Do Matter for Weight Loss?

When people think about weight loss, it’s usually the number on the scale that gets all the attention. But that number doesn’t tell you what you’re actually losing. Two people can lose the same amount of weight and end up with very different outcomes depending on how much of that weight came from body fat versus muscle.

That’s where the type of exercise you do can make a real difference.

In this article, we’re taking a closer look at a recent study that explored how resistance training influences not just how much weight you lose, but the quality of that weight loss. Our dietician breaks down what the researchers found, why preserving muscle matters more than most people realize and how this can shape your results both now and in the long term.

The Study

Resistance training as a key strategy for high quality weight loss in men and women

In this study, researchers looked at the effects of three different exercise types while the participants were in a calorie deficit for weight loss. Rather than focusing only on the number on the scale, researchers examined how much of the weight lost came from fat mass versus lean mass.

The Method

• Researchers examined 304 men and women who participated in a structured weight loss program at a nutrition clinic
• All of the participants were following a calorie-controlled diet (with a 500-calorie deficit) and coaching from a dietician to support weight loss
• Participants chose one of three exercise options:
  • Aerobic exercise 150-250 minutes per week. Activities such as treadmill or outdoor walking, elliptical training, stationary cycling and stair climbing.
  • Resistance training 2-3 times per week. A series of nine exercises utilizing weightlifting machines, free weights or body weight as resistance.
  • No exercise. These participants continued their normal activities of daily living without the addition of any intentional exercise.

The Results

• Interestingly, researchers found that all three groups of exercise lost weight across the 5 month period, but they found a difference in the type of weight the groups lost.
• The group that did resistance training lost more fat mass and preserved their lean mass (including muscle mass). Some participants in this group even increased their muscle mass despite being in a calorie deficit.
• When people followed a calorie deficit and either did aerobic exercise or no exercise, a portion of that weight loss came from their lean mass, which includes muscle tissue.

Our Dietician Explains

It’s important for us to first understand why it’s important to preserve lean mass during weight loss, in order to appreciate the results of this study. Lean mass is a term to describe muscle, bone, water and organs, so it’s not surprising that it’s the type of mass that we want to maintain for daily function.

Beyond daily function, muscle mass plays a key role in health and weight loss because of how much energy it uses even when you’re resting (your resting energy expenditure). Someone with higher muscle mass burns more energy even when they’re resting, compared to someone with less muscle mass. Losing muscle during dieting can lower resting energy expenditure, meaning the number of calories you need to eat each day to lose weight is lower.

This study found that the participants who did resistance training a few days a week maintained and even increased their lean mass (which includes muscle mass). While all three groups showed weight loss in this 5-month period, we can assume (with the support of other research) that the resistance training group will be more likely to maintain this weight loss over a longer period.

Instead of focusing only on eating less, consider how you can also train smarter. Even two to three resistance sessions per week can make a meaningful difference to your results over time. If you’re getting started with exercise, consider adding some body weight resistance training and slowly include weight training. YouTube has an excellent selection of videos led by qualified personal trainers.

Key Takeaways

1. Not all weight loss is equal

Losing weight is one thing. Losing mostly body fat while maintaining muscle is the ideal outcome. Resistance training helps shift weight loss toward fat loss rather than muscle loss.

2. Muscle supports your metabolism

Preserving lean mass can help maintain your resting metabolic rate. This may support long term weight maintenance and reduce the likelihood of regaining weight.

3. Strength training benefits both men and women

Resistance training is not just for building large muscles. It supports body composition, metabolic health, bone health and functional strength for everyone.

4. The scale does not tell the full story

This study reinforces an important idea discussed in our lesson Celebrating Your Progress On and Off the Scales. Body composition changes may not always be reflected clearly by the number on the scale. Tracking strength improvements, measurements and how you feel can give you a more complete picture of progress.

Bottom Line

If your goal is weight loss, resistance training is one of the most effective ways to improve the quality of that weight loss. By helping you lose more fat while preserving muscle, it supports a healthier metabolism and more sustainable results.

Reference

1. Lahav Y, Yavetz R, Gepner Y. Resistance training as a key strategy for high-quality weight loss in men and women. Frontiers in Endocrinology. 2026. DOI: 10.3389/fendo.2025.1725500.