Editor's note: Tabitha McMahon is one of six CNN viewers selected to be a part of the Fit Nation Triathlon Challenge program. Follow the "6-pack" on Twitter and Facebook as they train to race the Nautica Malibu Triathlon with Dr. Sanjay Gupta on September 8.
(CNN) -- Only 20 minutes so far? I can't keep sitting on this bike. It hurts. I'll just leave class and use the restroom. I don't need to go to the bathroom, but it will give my rear end a break. What if everyone stares at me? Oh no, now my toes are going numb!
These thoughts flew through my head during my second spin class a few weeks ago.
Recently, our Fit Nation workouts have picked up in intensity. I have tried new activities and pushed myself beyond my physical comfort zone.
When this journey began, I envisioned the biggest obstacle to my success would be physical. But after seven weeks of training, I have become acutely aware of the body part that needs the most conditioning. And much to my surprise, it's not my abs, triceps or quads. It's my mind.
I've come to the conclusion that wanting to stop mid-workout has little to do with my body and everything to do with my mind. I know many folks who experience negative self-talk, where that little voice in your head tells you all the reasons you can't do something. My internal dialogue seems to be less focused on telling myself I can't do it and more concerned with developing and executing a workout exit strategy.
My brain doesn't say, "You can't." It says, "You shouldn't."
Oh, but I should. And I am. Change your mind, and your body will follow suit. But how do you change your mind? That's the million-dollar question.
It turns out some cliches are true. The first step is admitting you have a problem.
Hi, my name is Tabitha, and I can talk myself out of a workout before I start. I had a long day at work. It's raining. I need to put gas in my car. It's Monday. Venus is in retrograde. You get the idea. Excuses and justifications are the path of least resistance.
Here are some other cliches that have proved true during my training:
Listen to your body, not your head. I've been in the middle of many workouts when I desperately wanted to stop. But when I focused on what I was doing, I could ask myself, "Do I want to stop because I am in pain? Or am I just uncomfortable because I'm sweating, breathing hard and making my body stronger?"
If I am honest with myself, the answer every time has been "I'm just uncomfortable." And guess what? I have finished every workout I have started.
The only thing we have to fear is fear itself. I recently read the amazing book "Finding Ultra" by Rich Roll. In it he writes, "There's only one cure for fear. Faith." That line resonated with me. It helped me understand that as an adult, fear has prevented me from realizing my full physical potential. In the past, fear is what has stopped me from even trying.
So now, if I find myself dragging my heels about a workout, I try to identify the why. Usually, it's something silly such as fearing the embarrassment of sharing a lap lane and slowing down another swimmer.
Now when I go to pool and find myself in this situation, I simply watch the swimmers for a few minutes. I try to identify someone close to my speed and skill level. I then ask if I can share the lane and tell him or her upfront that I am new to training. This has worked every single time.
The real key to overcoming these fears, as Roll pointed out, is faith. Have faith in your journey, in the universe and in yourself.
A picture is worth a thousand words. Everyone, even the toughest endurance athletes, occasionally struggle during workouts. Sometimes the only way I get through particularly tough workouts is visualization.
At times, it's remembering the two years I spent in nearly constant pain as I battled ulcerative colitis. Compared with that, the aches and weariness of triathlon training pale.
More often, I like to visualize my eventual triathlon success. I envision myself crossing the finish line on a warm, breezy day in Malibu, California, this September. I see myself running into the arms of my husband, daughter, parents and sisters. I imagine that magical mixture of physical exhaustion, elation, pride and disbelief that I actually did it. And it keeps me going.
Oh, and that spin class? I did not stop. I finished the class without stopping. And then I ran for 20 minutes afterward.
Follow McMahon on Twitter @TriHardTabitha.