Muscle & Metabolism
If you've been working hard to lose weight — eating cleaner, moving more, doing everything that's supposed to work — and the scale still won't cooperate, there's a question I'd want to ask you before we look at anything else.
How's your muscle mass?
It's not the question most people expect. But in my clinical experience, it's often the most important one. A slow or dysfunctional metabolism is one of the most common barriers I see in patients who can't lose weight or keep it off — and low lean muscle mass is one of the most common reasons a metabolism stops working the way it should.
Why Muscle Matters More Than Most People Think
Your muscles are the largest metabolically active tissue in your body. That means they're responsible for burning a significant portion of the calories your body uses every single day — not just during exercise, but constantly, around the clock, even while you're sitting at a desk or sleeping.
Each pound of lean muscle burns approximately 6 calories per day at rest. That number sounds modest until you do the math. Lose 10 pounds of muscle — which happens gradually and silently through your 40s and 50s without deliberate effort to preserve it — and your daily resting calorie burn drops by roughly 60 calories. Over the course of a year, that deficit adds up to more than 6 pounds of fat stored, without you changing a single thing you eat or do.
This is the mechanism behind what most people experience as a "slowing metabolism with age." It's real. But it's not inevitable, and it's not permanent.
The Problem with Low Muscle Mass
Muscle loss, or sarcopenia, typically begins in our 30s and accelerates through the 40s and 50s if we're not actively working against it. The causes are multiple — declining hormone levels (testosterone and estrogen both play a role in muscle maintenance), reduced physical activity, inadequate protein intake, and chronic low-grade inflammation among them.
The consequences go well beyond aesthetics or strength:
Resting metabolic rate drops — Your body requires fewer calories to function, so the same eating patterns that once maintained your weight now cause slow, steady gain.
Insulin resistance increases — Muscle tissue is one of the primary sites where your body stores and uses glucose. Less muscle means less capacity to process blood sugar efficiently, which drives fat storage and makes weight loss harder.
Recovery slows — Less muscle means less structural support, slower tissue repair, and more fatigue from the same level of activity.
The weight loss cycle worsens — When people crash diet without protecting muscle, they lose both fat and muscle. This makes the metabolism even slower — setting up the conditions for rebound weight gain the moment the diet ends.
Research consistently confirms this pattern. Studies show that people who lose weight while maintaining or building lean muscle mass keep that weight off at significantly higher rates than those who lose weight without addressing muscle composition. The scale can show the same number, but the underlying biology is completely different.
Muscle Loss and GLP-1 Medications — What You Need to Know
This is something I want to address directly, because it matters for many of our patients at NOVA Wellness.
GLP-1 medications — semaglutide, tirzepatide, and retatrutide — are powerful tools for weight loss, and when used appropriately with proper oversight, they can produce remarkable results. But here's what they don't do: they don't know the difference between fat and muscle.
When appetite is significantly reduced, most people also reduce protein intake without realizing it. Less protein means the body doesn't have the raw materials it needs to maintain muscle tissue. The result is that a meaningful portion of the weight lost on these medications can come from lean muscle mass — which, as we've discussed, directly undermines the metabolic foundation you're working to build.
This is why at NOVA Wellness, medical weight loss is never just a prescription. Every patient on a GLP-1 medication gets specific guidance on protein targets and resistance training — because the medication only does part of the work. The rest requires intentional effort to preserve what you're building.
What Actually Helps: The Three-Part Framework
The good news is that muscle mass responds to deliberate intervention at any age. Here's the framework I use with patients:
1. Resistance training, 2–3 times per week
This is non-negotiable if preserving metabolic function is the goal. Resistance training doesn't require a gym membership or complicated equipment. Bodyweight exercises, resistance bands, free weights — what matters is progressive challenge to the muscles over time. The research on this is consistent across age groups: resistance training preserves and builds lean mass, improves insulin sensitivity, and supports long-term metabolic health better than any other single intervention.
2. Adequate protein intake
Most people are significantly under-eating protein, especially when in a caloric deficit. The general target I give patients is 0.7 to 1 gram of protein per pound of goal body weight, distributed across meals throughout the day. For a person with a goal weight of 160 pounds, that means 110 to 160 grams of protein daily — substantially more than the average American consumes. Protein not only provides the building blocks for muscle repair and growth, it also has the highest thermic effect of any macronutrient, meaning your body burns more calories digesting it than it does with carbohydrates or fat.
3. Addressing the hormonal foundation
This is where the clinical picture comes in. Testosterone is one of the primary anabolic hormones — meaning it drives the body toward building and maintaining muscle. When testosterone is suboptimal (which is increasingly common for both men and women in their 40s and 50s), the body's ability to respond to resistance training and protein intake is compromised. Thyroid function, cortisol levels, and insulin sensitivity all play roles as well.
It's possible to do everything "right" — training consistently, hitting protein targets — and still struggle to maintain muscle if the hormonal environment isn't supportive. This is why a comprehensive evaluation matters. The labs guide the plan.
A Note on "Normal" and What It Actually Means
I frequently see patients who have been told their hormone levels are normal — and who are still losing muscle, still gaining fat, and still can't figure out why. As I've written before, "normal" is based on population averages, not optimal function. A testosterone level that is technically within the reference range can still be insufficient to support the muscle maintenance and metabolic health you're working toward.
This is why the approach at NOVA Wellness isn't to check a single number and call it done. We look at the full picture — total and free testosterone, SHBG, thyroid panel including Free T3 and Reverse T3, fasting insulin, inflammatory markers — and ask not "is this in range?" but "is this where it needs to be for this person to function at their best?"
Putting It Together
If your metabolism feels broken, it may not be broken — it may be under-muscled. And that's a solvable problem.
The path forward isn't more cardio. It isn't a stricter diet. It's building and preserving lean muscle tissue through consistent resistance training, adequate protein, and the right clinical support to make sure your hormonal environment is working with you rather than against you.
At NOVA Wellness, we don't just focus on the number on the scale. We focus on body composition — because that's where lasting results live. A patient who loses 30 pounds of fat while maintaining or increasing lean muscle mass is in a completely different metabolic position than one who loses 30 pounds of mixed tissue. The outcomes, long-term, are not the same.
If this resonates with where you are — if you've been working hard and not getting the results you expect, or if you've lost weight before only to watch it come back — a comprehensive evaluation may show you exactly what's been missing.
Ready to build a metabolism that actually works for you? Schedule a consultation with us. We offer comprehensive body composition evaluations, hormone panels, and personalized treatment plans designed to support your long-term health — not just a short-term number on the scale.
Call or text us today to book your appointment.
Matt Nelson, NP
NOVA Wellness — Orem, Utah
(801) 449-1402 · novawellnessut.com
