Hey There! 

I’m Cori Lefkowith, Owner of Redefining Strength

I started Redefining Strength in 2014 with one mission… 

That mission goes beyond goals. We’re here to provide you with a science-backed approach that not only supports your health and fitness journey but also empowers you through education.

My team of experts will guide you in building habits that seamlessly become a part of your lifestyle, ultimately reshaping your identity. Get ready to redefine what strength means to you and embrace a transformative experience with us.

My Story

Like most people, I was clueless when I started trying to get in better shape after gaining weight after college. I picked up some fitness magazines and started working out with no direction. 

I carried on that way for a long time, jumping from diet to diet, workout program to workout program, and supplement to supplement. No matter how hard I tried, I always felt like my body looked the same, and my energy was awful.

I’ve been the idiot who has made every mistake and experimented… even with ridiculous things. I’ve been stuck in that cycle of dieting and depriving myself, binging, feeling guilty, binging again, and then trying a new diet.

I’ve ignored injuries and pushed through, only to end up more injured. I’ve gained weight and lost weight. I’ve worked out hard and then slacked off because I was so burnt out.

And because I’ve made all the mistakes, I now know what works. That’s why I can help you.

I realize that each person has unique needs, and no two fitness journeys will look alike.

I realize you’re going to slip up. Mentally, sometimes you’ll want to give up or start beating yourself up.

I realize you may even be scared to start something new and step outside your comfort zone.

That is why I create programs for real people that meet their individual needs.

With over a decade of experience in the fitness industry, I take pride in implementing a scientific and research-backed approach that leads to amazing results. After witnessing over tens of thousands of people implement and go through my programs, I can confidently tell you what works and what doesn’t work…

Supplements are Supplemental

I’m not going to sugarcoat it for you. There is no magic weight loss pill or secret muscle building supplement. If that’s why you’re here I’ll save you some time! You can click back and close this page out right now. Sorry to burst your bubble. but SUPPLEMENTS ARE SUPPLEMENTAL! 

Your workouts and your nutrition drive your results.

With that being said a proper supplementation plan can help us speed up results and create something sustainable you can do long term. And because each of us are different a customized formula might be what’s missing to fill your individual nutritional gaps.

While I loved my previous supplement line with protein powders I wanted to provide you with an option you can’t find anywhere else. Supplements are a tool you can use to optimize your performance. Why wouldn’t you use every tool at your disposal to get the fastest and best results possible?



Here’s How It Works…

Step 1. Consultation

You’ll speak with a Redefining Strength Registered Dietitian to go over your goals, lifestyle, health concerns, and, if desired, even your bloodwork to create a unique supplement for you. The involvement of Redefining Strength Registered Dietitians (RDs) in the process adds a layer of professional oversight and ensures your supplement is based on the latest scientific research.

This prevents the risks associated with self-prescribed over-the-counter vitamins and ensures that the supplements are both safe and effective. We can even adjust and modify your formula as your goals and lifestyle change.

Step 2. Formulation

After your call, we get to work creating the formula for your custom supplement. We hand-pick from over 250 premium-quality ingredients to create a blend unique to you. We customize the dosage down to the milligram and microgram of each ingredient.

We only use the most effective and bioavailable ingredients for your personalized formula. There are no artificial fillers or binders, just the highest quality ingredients.

This is also the fun part where you get to pick your own supplement name to see on the packaging.

Step 3. Production

We’ve partnered with an NSF GMP certified manufacturing facility to ensure your supplement is of the highest quality available anywhere.

Your formulation is tested three separate times for purity and quality: when the raw materials are received, during production, and before we ship you the final product.

We conduct both internal and third-party testing, including microbiological testing, physical testing, analytical concentration testing (e.g., ICP-MS, HPLC), and identity testing (FT-IR).

Step 4. Optimization

After making your supplement, we ship it directly to your doorstep. Whether you select a 3-month supply or a 6-month supply, you’ll receive your product in fully recyclable packaging, along with your unique instructions on how to take it.

After you finish your supply, you’ll check in with your dietitian. We can adjust your formula from there based on your current status. Have your goals changed? Have your symptoms improved? Your formula can change and adjust as your body does.


Redefining Strength

In 2014, I founded Redefining Strength as an in-person fitness facility in Southern California.

Our training style focuses on functional fitness and developing a sustainable lifestyle through building habits.

Since then, Redefining Strength has evolved into a Comprehensive Online Coaching Program along with our Dynamic Strength App and Registered Dietitian-created Custom Meal Plans.

While we still have our physical facility for in-person events and certifications, it is no longer open to the public for classes. Because I wanted to help more people and impact more lives, our program transitioned online. Now, our world-class coaching and programs can be experienced from anywhere in the world, allowing us to reach a wider audience and make a greater impact.

Our newest offering is custom supplements formulated just for you



The Team & Qualifications

Check out a Podcast With The RS Nutrition Team

While I personally have over a decade of experience in the fitness industry, played Division I college tennis, won a state powerlifting championship, and hold multiple certifications, including being a certified personal trainer (CES, PES, FNS, SFS, TFW, and Battle Ropes Level 1), the power and magic of Redefining Strength lie within its team. Together with a team of top experts in their respective fields, we are committed to helping you achieve your fitness goals and transform your life.

At Redefining Strength, our team consists of highly qualified professionals who are dedicated to helping you achieve your fitness goals. Our staff includes individuals with various advanced degrees, such as an MS in Exercise & Sport Studies, an MS in Nutrition & Dietetics, and an MS in Health Exercise & Sports Science. We also have multiple Registered Dietitians (RDs) who specialize in different modalities, providing comprehensive nutrition guidance.

To ensure the highest level of expertise, we have a rigorous selection process for adding new team members. In fact, the last time we expanded our team, we hired less than 3% of the applicants. Harvard and MIT accept and approve more applications than I do 😉

We take pride in the qualifications and expertise of our specialty trainers. They undergo thorough vetting and possess a wealth of knowledge in their respective areas. When you work with our team, you can be confident that you are receiving guidance and support from professionals who are not just qualified but truly overqualified for the task at hand.

With our highly qualified and dedicated team, you can trust that you are in capable hands as you embark on your fitness journey. We are committed to providing you with the best possible guidance, support, and expertise to help you redefine your strength and achieve your goals.

Click here to learn more about our individual team members and qualifications

We also have our own Strong Smart Certification, which is globally recognized by esteemed organizations such as the National Academy of Sports Medicine, the American Exercise Council, the International Sports Sciences Association, and the Athletics and Fitness Association of America.

Our Core Values

At Redefining Strength, our core values of OWNERSHIP, SYNERGY, DRIVE, and PASSION shape everything we do. We take ownership of our actions and constantly strive for improvement. Our team is dedicated to creating a supportive and collaborative environment where everyone is valued and respected.

We are driven by an unwavering pursuit of education. Above all, we are fueled by passion – a passion for our mission and a genuine desire to witness every person we help experience positive transformation.

We take great pride in our achievements. Redefining Strength has garnered global recognition and has been featured in renowned publications such as Women’s Health, Insider, Livestrong, Self, Cosmopolitan, Shape, Elite Daily, IDEAfit magazine, and more. We were also honored to be named a top 10 home workout by The Guardian.

P.S – Be sure to check out our reviews and testimonials

RS In The Press