How This Biomedical Engineer Invented A Device To Run Better

Published: September 6th, 2022
Sarah Anderson
Founder, Celer
from New York, NY, USA
started March 2020
Discover what tools Sarah recommends to grow your business!
Discover what books Sarah recommends to grow your business!
Want more updates on Celer? Check out these stories:

Hello! Who are you and what business did you start?

Hello! Thanks for having us. My name is Sarah Anderson and I am the founder of Celer Ergonomics. Celer is an athletic training brand focused on creating products that re-train your body to move with better movement patterns, as you move. Our first product, the RunCeler strap, is a functional resistance band worn over the sock and in the shoe while running to promote improved running form, thereby decreasing the risk of injury and improving performance.

We believe that everyone can move better and it is our mission to enable everyone to experience the health benefits of running and working out without added pain or injury.


How it works: Using active resistance, the RunCeler strap engages the muscles of the foot to land with a more mid-foot strike, a striking pattern linked with decreased risk for overuse injury. Additionally, the material properties of the RunCeler strap act as an external plantar fascia to promote enhanced athletic performance.


Currently, Celer is a small 2-person start-up out of NYC comprised of myself and my fiance, Tony Gardner. The concept of the RunCeler strap was fueled by personal experiences with overuse injuries during our D1 athletic careers coupled with educational backgrounds in engineering and kinesiology and a passion for biomechanics.

To date, we have 4 published patents on the RunCeler strap and we’re currently on the feet of hundreds of runners, growing 20% month over month.

As we grow our business, we are looking to expand our influence and gain traction in the fitness community, with a primary focus on the running community.

What's your backstory and how did you come up with the idea?

I love running, and like most of us, I hate injury. Specifically, I hate overuse injury because it has plagued my running career. I ran (and won) my first 5k when I was 9, and then coincidently, I experienced my first overuse injury at age 10.

An overuse injury is defined as damage to the bones, muscles, ligaments, or tendons because of repetitive stress. Common examples include runners’ knees, ITBS, shin splints, and plantar fasciitis (my specialty).


My trend of being sidelined from the sport due to overuse injury continued about every 2-3 years right up through college. Though I tried everything on the market to prevent yet another overuse injury (i.e. different running shoes, physical therapy, personal training, and different arch supports), it was also just a matter of time before my next sidelining injury occurred.

Growing up in Albany, NY, my parents were very supportive of my interest in STEM, and I was fortunate to attend Georgia Tech on a full academic scholarship to study biomedical engineering. Though I had been injured during my junior year of high school due to metatarsal stress fractures, I worked extremely hard to walk on to the Georgia Tech Division 1 Cross Country team in the Fall of my sophomore year. Coupling my education with my athletics, I soon became obsessed with the biomechanics of running.


Chasing my thirst for knowledge in sports biomechanics led me to do research at a premier sports engineering university in the UK, Loughborough University, and after college, I worked as a mechanical engineer with the Adidas running innovation team in Herzogenaurach, Germany. I was the lead human ergonomics engineer for a small start-up orthopedic venture in Los Angeles and I shadowed pedorthists and podiatrists to learn about foot deformities.

I even worked in a local Fleet Feet to gain consumer insight and as a personal trainer to learn about functional movement. I finally settled into a position monitoring the nerves during spine surgery, certain I wanted to pursue medical school and become an orthopedic surgeon.


Meanwhile I continued to run, and I just couldn’t stop thinking about ways to improve my running form through improved biomechanics to prevent injury. Using myself as a guinea pig with no real goal in mind other than to hopefully prevent another injury, each month I would tweak something about my form, be it the introduction of a new product or a slight change in technique, and take scrupulous notes of its impact.

At about this time in the mid-2010s, the benefits of “barefoot running” (where a runner lands with a mid-foot strike as opposed to a heel strike) were the talk of the sports science community. While this certainly intrigued me, the thought of stuffing my toes in 5 fingered Vibrams to enforce a more “minimalistic foot-strike” made me cringe, and I was not going to actually run barefoot in a busy city! And that’s how I came up with the concept of the CelerRun Strap.

To prevent future running injuries I realized I needed to change my running form, but there was no product compatible with my running shoe that helped to re-train my running gait from a heel strike to a more mid-foot strike.

After realizing that no product functionally helped to change a footstrike and strengthen stabilizing foot muscles as it was worn, I set out to create what is now known as the RunCeler strap. The RunCeler strap is a running resistance strap worn over the sock and in the shoe that trains a runner to run with a more mid-foot strike, thus achieving the benefits of barefoot running without actually running barefoot or having to wear special shoes.

When I get onto something, I can't stop. I've spent years researching the why, and years more determining the solution. I'm proud to say I've been injury free since I started to wear Celer.

In 2020, the number of runners increased globally by about 30% due to COVID, and I had an influx of friends and family asking for their own pair of RunCeler straps. That is how Celer (the business) was born.

Take us through the process of designing, prototyping, and manufacturing your first product.

I spent about 3 years developing the RunCeler strap, in addition to the prior 3-4 years testing out different existing market solutions. In early stage prototypes, I experimented with sewing two materials together to achieve the desired resistive effect.

Once I had settled on the idea of what Celer would be, I filed provisional patents to be able to further solidify my design before needing to submit the full patent application. In the U.S patents are based on first to file so it is important to file at least a provisional patent up front.


As a solo inventor moonlighting in product development in addition to a full-time job, I had to get creative as I did not have any connections or money to contract material developers. I used Google translate and innovative stories to gain the interest of manufacturers, and finally, as luck would have it, one day I struck gold. A small family-run manufacturer was willing to produce new resistive material at my specified material specs with no money up front, no minimum order quantity, and no commitment for additional orders.


When I received the material a few months later, I realized I had no idea to sew velcro or anything about how to adhere the strap to an athletic sock. I had never really thought of the actual design/manufacturing process until it was upon me. Similar to finding a creator and manufacturer for my novel material properties, I cold called hook and loop manufacturers across the globe and requested large quantities of material samples in return of a promise of “big business” in the future. Post COVID I found a cut and sew manufacturer in NJ.

Fun facts about prototyping and bootstrapping a start-up:

  • My first material patterns were hand traced from cardboard cutouts and cut with scissors
  • It took me 6 months to learn how to sew hook and loop onto specialized rubber latex material…and it took me 2.5 hours to sew (1) pair of RunCeler straps.
  • Patents can take upwards of 5 years to get published!

For me, the largest obstacle to overcome was the shift in mindset from inventor to the face of the product.

Describe the process of launching the business.

We have had a website for approximately 5 years. The first iteration looks much different than it does now (current iteration pictured below). During the early stages, it was more than just having a presence during the end of development, but it’s evolved into a production we are proud to have out.

The business thus far has been self financed. We have received $15,000 in funding through the NYU Stern Ventures group. The next stage in terms of financing is to open and friends and family funding round and then the fun starts!


One of the challenges we have is that we have an international supply chain. There are a lot of points where bottlenecks can, and have occurred (even without viruses and cargo ship beachings). We are always in the process of evaluating all aspects and looking for ways to improve or add redundancy, but It is challenging as our focus is split amongst so many different avenues.

One of the larger time commitments during our launch was creating social media content. Neither of us is strong in graphic design and video editing. Our creativity lies in product and process, not quirky videos. So there has definitely been a ton of growth over the last calendar year in that regard, but it is without a doubt the weakest part of Celer.

Our true Launch Started in the first Quarter of the year. We have a 3 staged launch strategy. First, We are Starting in the New York City Market, as well as developing a brand Identity through Social Media. The Next Stage is to build our B2B sales in the Market and increase Social Media reach through increased marketing spending. The third phase is to expand through major metro areas with boots on the ground to engage the local users, small shops, and health facilities.


Since launch, what has worked to attract and retain customers?

We did not start with our first social marketing campaign until late Q2 / early Q3 to coincide with the summer running season in NYC. This “launch” campaign focused on brand awareness and product functionality. We called this campaign ‘Celer Origins’.

As a new brand, it is important to position yourself in the community, and being in a large metro area such as NYC has helped. With the Celer Origins campaign, we mixed social media marketing with in-person launch events such as pop-ups at different running events throughout the city and demos with different running groups. The Celer Origins campaign focused heavily on my personal why and the background of product development that led to the formation of Celer.

On social media and in person, we found that runners resonated with Celer’s backstory and were united in a shared desire to improve their running performance and decrease their associated running pain.


For each in-person marketing event, we created a unique discount code to enable us to track what type of event created the largest conversion. Then, we targeted those specific activities in different areas of the city at different times of the day. This allowed us to further drill down into the specific events that drew in different groups of customers. Another marketing strategy we employed during pop-ups at athletic events was related to messaging.

For each race and event, we would change minor things about our display, promo materials, and in-person messaging. Taking notes on what worked best we were able to further fine-tune promotional strategies to enable better sales conversions.

Now, we are moving into our second marketing campaign “Celer Community”, where we are turning the focus onto runners in our community that has had positive experiences with Celer, either eliminating their running pain and/or helping them achieve their fitness goals. Peer-to-peer recommendations have catapulted our sales and it is so fulfilling to hear about lives that were changed because of our product.

How are you doing today and what does the future look like?

We are doing great! We admittedly had a rather lengthy development period followed by Supply Chain and sourcing issues seen across all markets with COVID19 delays, but we finally were able to launch commercial efforts earlier this year.

Currently, marketing efforts are split 50% via Social Media and 50% grassroots. Using social media allows us to especially track what content translates into sales, which has been enlightening. Neither of us comes from a marketing background, so we have relied very heavily on our network to fill in the gaps.

The grassroots efforts have been subdivided into Running group demos, Race support, and Physical Therapy/Personal training Gym services. These are very labor intensive, but allow us to understand the customers at a deeper level. We believe this will give us advantages as we scale outside of NYC and future product launches as the portfolio expands.

Currently, we are not spending any money on advertising. We have created custom packaging for “unboxing” videos for individuals of influence so that we can create some contagion among our users' networks. As we continue to learn the customers and validate purchase verticals we will direct capital to those areas.


From a production standpoint, we currently source materials from several companies and deliver them to an industrial seamstress. We have a lead time of about 8-10 weeks to receive the finished product. Our volume currently allows us to package and mail them out of our home office, but once we hit one of our volume targets we plan to outsource that.

Currently, Gross Margin is ~60%. This is a bit variable with inflation of course, but we believe at a scale we can increase this number by 10-20%. We have to add that during Alpha testing we explored various price points, and through the NYU Stern venture competition feedback and other seasoned entrepreneurs, our originally forecasted price point of $35 got hammered as being way too inexpensive. That was the most common feedback we received from any person in an advisory position.

Future directions we plan to go from a marketing/sales perspective include sponsoring run clubs/ bringing in running key opinion leaders to continue to engage users, entering into retail stores, Celer pop-ups, and B2B sales in the health service space. We plan to take the lessons we learn in NYC over the next 6-12 months and apply that to additional metropolitan areas.

The RunCeler strap is the first product to be launched in our portfolio and is focused on improving the functional efficiency of the foot/ankle joints during sport. We have a long-range plan to expand our product offerings within the foot/ankle space and create horizontal value creation through offerings targeted at improving movement patterns in other joints subject to overuse injury (i.e. elbow, knee).

Through starting the business, have you learned anything particularly helpful or advantageous?

Starting a business is such a wild ride! I definitely did not have a full understanding of all that entails starting a business when we decided to go forward.

For me, the largest obstacle to overcome was the shift in mindset from inventor to the face of the product. For us, most of our marketing is done through social media platforms , whichwasn’t something I was entirely comfortable with ainitially It’s been a really fun process to get into the weeds of marketing and customer outreach.

Something surprising to us was how willing everyone is to help. The entrepreneur community is so incredibly inviting. We have had so many great conversations with entrepreneurs that really helped to direct our focus. We always had a pretty strong idea of the direction we were going to take the company, but we have been given an incredible amount of invaluable advice simply by asking. Even if an individual can’t give us a meeting, we have had strong feedback / advice through email. So if you’re struggling, a lot of people are there to help!

What platform/tools do you use for your business?

Favorite business tool is Google insights. For us, to understand who is seeing Celer, and how to reach the most people has been fun.

Canva has improved our graphic design while Shopify has enabled an easily customizable e-commerce platform. We switched from Wix to Shopify via the help of Shopifree, a free design service that switches over websites and assists with re-design at no cost!

Klaviyo has upped our email marketing campaigns and is free to use with Shopify. is helpful for project planning and Planoly is a great app that allows you to plan and view social posts.

What have been the most influential books, podcasts, or other resources?

I am currently finishing up my MBA at NYU, and the resources they have been able to provide through Venture competitions to the Stern Venture Group have been invaluable. From mentors to funding, to learning resources. Its really been invaluable to Celer as we have begun to move.

For books, I have really gained a lot of knowledge from the Johnan Berger series on marketing. Contagious: Why Things Catch On, Catalyst, and Invisible Influence: The Hidden Forces That Shape Behavior.

Advice for other entrepreneurs who want to get started or are just starting out?

My Advice for other entrepreneurs is to find your passion and find a way in which people respond as favorably to it as you do.

I love running, and I hate being injured (like everyone). I have been able to reach so many people through Celer who have similar stories, and similar struggles. I’ve learned that when starting a new brand, people need to fall in love with the story and purpose behind the brand, and that often focuses on the founder.

Additionally, it’s never too late to start on the journey towards your dream. No one is more committed to your dream than you are, and that’s what will carry you through. It’s no work if you love it!

Are you looking to hire for certain positions right now?

We are pretty bare-bones right now as we scale operations and revenue. Currently gearing up to make the rounds for Friends and family/Seed funding, But once we have the resources our first hire will be in Marketing/Social Media. If you love running, marketing, and startups drop us a line at [email protected]!

Where can we go to learn more?

If you have any questions or comments, drop a comment below!