This is an episode about a gym that started with one strength coach fully booked out of a sub-1,000-square-foot studio and is now a 5,800-square-foot performance center, and about the partnership between a marketing operations lead and a strongman competitor that made the transition possible. Danielle Collen’s story starts before the gym, in the parts of the fitness industry most gym owners never see, inside the software companies that sell them their booking systems. She’d started in graphic design at art school, realized quickly it wasn’t for her, switched to marketing at Alfred University in New York, and went on to her MBA. Her career specialized in marketing operations for fitness software companies, including ABC Fitness, which owns Glow Fox and Trainerize, and Gym Desk, where she still consults. She learned the gym industry from the vendor side first: how leads move through pipelines, what onboarding actually needs to cover, why processes have to be written down before they can scale.

Her husband, Justin Collen, came at it from the opposite direction. He is a competitive strongman, a Certified Strength Coach with a Masters in Exercise Science, a functional nutrition coach, and the kind of trainer whose reviews describe him as tailoring programs the way a bespoke tailor fits clothing. His trademark phrase in sessions, according to those same reviews, is “Be better, do better.” He was operating in Texas doing one-on-one training when they decided to make the move to Colorado.

Colorado was a family decision as much as a business one. Danielle and Justin have a four-year-old, a two-year-old, and a third child due within weeks of the interview, and the Texas heat had made outdoor life with young boys hard. Colorado offered a healthier demographic, a stronger outdoor culture, and, as Justin quickly found once they arrived, a networking-friendly business community that Texas hadn’t provided. He started as an independent contractor in a 24/7 gym, built a client base through conversations on the floor, joined business networking groups, and quickly outgrew that arrangement. He leased his own space, under a thousand square feet, and within a short window was booked every hour of the day with a waiting list behind that. The next move was inevitable.

What they built to receive the next stage is deliberately specialist. Grit to Greatness is not a community gym and doesn’t pretend to be — it’s a performance center inside a completely renovated former Advantage Auto store on Sunny Glen Court, with a large gym floor, a separate cardio room, a private training room, and a private treatment room subleased to a physical therapist with more than twelve years of clinical experience. The programming stack runs from gym-access memberships for people who want a serious training environment without the crowd, through Justin’s 12-week app-based programs, through small-group personal training capped at six to eight people, up to one-on-one coaching and dedicated space for youth performance teams and student athletes on college recruiting tracks.

The choice that most separates them from other gyms is a hiring one. Where most gyms bring on trainers as independent contractors and let each build their own book, Justin and Danielle hire employees at set rates, because Justin’s vision is one team with shared programming standards rather than a floor of freelancers wearing the same t-shirt. That decision only holds up because of Danielle’s second contribution, which is documentation. She has ported the sales development processes, onboarding SOPs, and coaching playbooks from her fitness-software career into the gym, so that a new performance coach can walk into a first meeting with a prospective one-on-one client and know exactly what to say. Her own line for it is that the two of them are marrying elite coaching and operations discipline, and it shows in the way growth has moved without collapsing quality.

Their arrival at Wellyx follows the same pattern as everything else about the business. Danielle had already looked at Glow Fox, Trainerize, Gym Desk, Push Press, MindBody, and Gym Master, and had actively trialed Gym Master before giving up on it as too complex to train staff on. She went to ChatGPT with the list of things Gym Master had failed at and the capabilities she still needed, and Wellyx was what came back. What closed the decision was the combination of user-friendliness she could actually train staff on, 24/7 customer support that responded the same day rather than on a corporate three-day turnaround, and door access control that let her offer gym-access memberships without staff on-site. She’s been direct about the developmental gaps she’s asked for, automatic tax withholding for US payroll, which she’ll bridge with Gusto in the meantime; extended booking windows beyond twenty-four sessions; package expiry adjustments, and equally direct about the fact that the customer service team has moved on each request rather than deflecting.

At the time of the interview, just before the new facility’s ribbon cutting, the member base was thirty one-on-one clients with fifty to sixty active leads waiting for either private slots or the small-group cohorts. Marketing had generated all of that with zero paid social spend, entirely through networking groups, referrals from physical therapists and massage therapists, and Justin’s presence at the local Teller Business Builders chapter. Danielle’s takeaway for other founders is understated and worth taking seriously: figure out the identity of the brand starting small, gather input from real members, put yourself out there, and the growth follows. And once it does, document it. Because the speed of growth catches up fast with a business that hasn’t written down how it works.