Case Study

Balance. Vitality. Longevity.

From Plateau to Podium: How Brittany Reclaimed Her Physique and Vitality at 41

In the world of competitive fitness, there is a common misconception that once you hit your 40s, your “best days” are in the rearview mirror. For Brittany, a former bikini bodybuilder in her 30s, the drive to return to the stage was there, but her body wasn’t responding like it used to.

Despite getting 8 hours of sleep, her energy was nonexistent. Despite a “good” diet, she was trapped in a 20lb yoyo cycle. She tried the standard “weight loss shots,” but GI distress forced her to stop.

When Brittany came to Thrive Wellness Institute, we didn’t just give her a diet; we rebuilt her metabolism from the molecular level up. One year later, the data tells a story of one of the most successful body recompositions we have ever witnessed.

The Starting Line: January 2025

Brittany began her journey at 178 lbs with 32.8% body fat. While she had a strong athletic foundation, her metabolism was “stalled.”

Lean Mass: 95.5 lbs
Visceral Fat (The dangerous fat around organs): 10
Metabolic Age: 41 (Exactly her chronological age)

Her labs revealed the “why” behind her fatigue: her Testosterone was sitting at 23 ng/dL—on the lower end for an active female—and her protein intake was insufficient at only 80g daily to support muscle protein synthesis.

Hormonal Foundations

The Thrive Protocol: The Science of the Transformation

To get Brittany back into “Bikini Pro” shape, we moved away from generic weight loss strategies and implemented a targeted Peptide and Hormone protocol.

The Metabolic Engine: Retatrutide (Reta)

After struggling with GI issues on Tirzepatide, we transitioned Brittany to Retatrutide, starting at 1mg and titrating to 3mg. Unlike its predecessors, Retatrutide is a “triple agonist” (GLP-1, GIP, and Glucagon). The addition of the Glucagon receptor agonism was the game-changer for Brittany; it increased her metabolic rate and thermogenesis while being much gentler on her digestion.

Hormonal Optimization: Testosterone Replacement

We optimized Brittany’s testosterone, bringing her from a baseline of 23 ng/dL to a vibrant 77 ng/dL. This wasn’t about “bulk”; it was about recovery. This shift is what allowed her to finally break the fatigue cycle and maintain her lean muscle mass even while in a significant caloric deficit.

The "Holy Grail" of Peptides: Tesamorelin & Ipamorelin

We cycled a combination of Tesamorelin and Ipamorelin.

Tesamorelin is FDA-approved specifically for the reduction of visceral fat.
Ipamorelin stimulates the natural release of growth hormone without the “hunger spikes” associated with other peptides.
This duo is largely responsible for her visceral fat dropping from a 10 down to a 6.

Mitochondrial & Fat Oxidation Support

We rounded out her protocol with L-Carnitine (to shuttle fatty acids into the mitochondria to be burned for fuel) and 5-Amino-1MQ. 5-Amino-1MQ is a cutting-edge peptide that blocks the NNMT enzyme, effectively “turning on” the metabolism in fat cells and increasing cellular energy (ATP).

The Foundation: Protein & Resistance

Peptides are the “turbocharger,” but the diet is the “fuel.” We moved Brittany to a 120g protein target to protect her muscle tissue. We also made a counter-intuitive shift in her training: we lowered her cardio. By switching to 2-3 days of low-intensity walking and 5-6 days of heavy resistance training, we lowered her systemic cortisol (which was 16.5 ug/dL) and allowed her body to stay in an anabolic (building) state rather than a catabolic (breaking down) state.

The Results: January 2026

The “After” data is nothing short of a Masterclass in Body Recomposition.

The most incredible stat: Brittany lost over 47 pounds of total weight, yet her Lean Mass actually increased. In traditional weight loss, you typically lose 25% of your weight from muscle. By using our peptide and hormone protocol, Brittany lost pure fat while actually getting stronger.

Summary from Thrive Wellness Institute

Brittany’s metabolic age is now nine years younger than when she started. She has reclaimed her energy, her confidence, and her “bikini-ready” physique.

Her transformation proves that with the right data, the right peptides, and a commitment to protein and lifting, your 40s can be your strongest decade yet.

Are you ready to see what your body is truly capable of? Contact Thrive Wellness Institute today for your comprehensive lab review.

Body Metrics Comparison

Metric	January 2025	January 2026	Change
Weight	178 lbs	130.6 lbs	-47.4 lbs
Body Fat %	32.8%	20.8%	-12%
Lean Mass	95.5 lbs	96.2 lbs	+0.7 lbs (GAINED)
Visceral Fat	10	6	-40%
Metabolic Age	41	32	-9 Years