Three months before my 50th birthday, I decided I wanted to get into shape. My goal: to be in better shape at 50 than I was at 25. This was a low bar for me to set. Although I was skinny at 25, I wasn’t in shape. My physical activity at the time took few forms: doing laundry, sometimes running across the street if the light was about to change. I couldn’t run down the block without getting winded.

With my milestone birthday looming, I decided to try CrossFit. Correction: a funny and fit man I had recently started dating suggested trying CrossFit. I was game: I remembered seeing a friend transform herself several years ago. She had become rather zealous about the experience, but I had successfully rebuffed her proselytizing.

I was also sold by the convenience: I was a single mom with a full-time job and time was precious. The gym was in Old Colorado City, about 10 blocks from home. I could practically walk there – if I had had the time, let alone the energy. There were at least nine classes offered each weekday, starting at 5 a.m. and ending at 7 p.m. and a few classes over the weekend. I would be hard-pressed to come up with the excuse that I couldn’t fit it into my schedule.

While CrossFit was beginning to make sense from a practical perspective, the prospect of walking into the gym as a client was wreaking havoc with my self-esteem. I should lose a few pounds first. I’ll look old. Worse: I’ll look foolish! The preliminary visit I made to the gym didn’t help, despite the friendly coaches who welcomed me like family. Oh my God, look at all these beautiful, fit, smiling people. I don’t belong here.

For months, I would hear my Negative Nelly whispering in my head before each class, starting before I even changed into my workout clothes. You’ve had a long day, go another day. And then on the drive: There are going to be burpees today and last time you could barely do three. Do you really want to put yourself through that? And then upon entering the building: Oh, I am so out of my league. She can be a real chatterbox.

There were so many opportunities to talk myself out of going to the gym and once there, out of returning. Despite being encouraged to “scale” the workout to our individual fitness level (a beautiful concept, by the way), the workouts were still designed to be hard. It wasn’t easy to be reminded – each time my body felt completely spent – that I had a long way to go before I would feel in shape. But no matter how challenging it was physically, the more persistent challenge was always in my head.

Thankfully, I didn’t listen to the advice of the ubiquitous fitness guru: “Be tough! Push yourself! Fight through it!” If I had, I would have quit. Early on, during the delicate phase of creating a new routine, that approach is too unforgiving – too similar to the undermining needling of my Negative Nelly who, if she had had her way, would have prevented me from even walking through the gym door. I learned that the first and most important exercise was quieting my Negative Nelly with a simple statement: Walking in is the win.

Two years later, I’m still proud of myself every time I walk through CrossFit SoCo’s doors. Turns out that one thing I had going for me was that I was nearly 50. I have some perspective and some self-compassion. I have been around the block. And unlike my 25-year-old self, I’m not winded yet.