The newest trainer on the new season of "The Biggest Loser" opens up about her 150-pound weight loss and the challenging lessons she learned along the way.

I weighed 322 pounds five and a half years ago and was completely okay with it.

I'd started gaining weight around middle school, and food and fitness just weren't something my family talked about at home. My mom worked a lot, and my siblings and I grew up eating whatever snacks she'd stocked in the pantry. After meals, we'd always have dessert. That's just how my family, like so many others, showed love: through food. (Related: How to Use Intuitive Eating for Weight Loss)

By the time I got to college, there was nothing holding me back from eating whatever I wanted. There was no one around to tell me "no", and I didn't think there was anything wrong with eating fast food and pizza every day. Food aside, I also had no idea that working out and moving your body is important. I'd never been to the gym, and I never really felt the need to go. Why? Because no one really said anything about my weight or the way I looked. No one seemed to think there were any red flags about my health, so neither did I. (Related: This Woman's One-Year Transformation Is Proof That New Year's Resolutions Can Work)

To be honest, I don't have one of those stories where I can tell you that I looked at myself in the mirror and hated myself. I was truly just oblivious. I mean, I knew I had some weight to lose, but at 5 foot 11 inches tall, I just felt like I was a big girl and was ever going to have a tiny waist or small thighs, and that didn't bother me.

As years passed, I continued living life the same way and the weight kept piling on. I got married and gave birth to my son a few years later. My whole life I'd wanted to be a mom so badly and I dove into motherhood with my whole heart. (Related: This Influencer Is Keeping It Real About Stepping Into a Fitting Room After Having a Baby)

I continued to gain weight after pregnancy but still didn't really think I had any problem. My wake-up call finally came when my son was 3 years old and playing on our living room floor. I was sitting on the couch when he looked up at me and asked me to join him. I said no.

I vividly remember sitting on that couch with zero energy, eating some kind of snack, not wanting to get up because doing so felt like too much effort. At that moment, something clicked. I looked at my son and realized that I brought him into this world and he deserves so much more than a mom who doesn't even have the energy to play with him. I had to make a change and I needed to make it fast while I had the motivation.

The Physical Transformation

While I still knew nothing about diet, weight loss, or fitness, the one thing I did know was that I need to reduce my calorie intake and increase my activity level. (BTW, the weight loss concept of 'calories in versus calories out' is not as simple as it sounds. Plus, counting calories is not the end all be all of losing weight.)

The initial changes were small. As far as food was concerned, I was still cooking pasta and pizza, but consciously eating smaller portions. Then began eating low-calorie frozen meals. At the time, I didn't know that those came with their downsides too, but to be honest, all things considered, it was a good place to start. Eventually, I began educating myself on food and started learning about fat, carbs, proteins and how to eat balanced meals that fueled me versus comforted me. (Related: New Energy Foods to Power You Through Your Day)

When it came to fitness, I started by joining a local Planet Fitness. I went in the mornings before my son woke up and began by just walking on the treadmill. A few weeks in, I felt comfortable challenging myself and would jog for 30-seconds a few times during my walk. I just kept building upon that goal. Soon, I was jogging for the length of one song on my playlist, then two songs. My goals just kept growing from there. (Related: What Might Happen If You Walk 30 Minutes a Day)

For the first two months, I stuck to cardio. I averaged about five hours on the elliptical and treadmill a week. Then, I started working with a trainer who showed me some high-intensity interval training (HIIT) drills. While I could feel the weight coming off of me, I also wanted to build muscle and HIIT was a good way to work toward that. Once I adopted this workout strategy, I discovered what "good tired" meant and I became hooked to that feeling. (Related: How to Make Exercise a Habit You Love)

The Internal Growth

In the first month of my journey, I lost 45 pounds. At the end of the first year, I was down 122 pounds. Every month I watched the weight come off my body. My clothes stopped fitting me and my energy levels shot up. (Related: The #1 Thing You Should Keep In Mind Before You Set Weight-Loss Goals)

But the biggest transformation for me was internal. During the early stages of my journey, I began documenting my experience on social media, and I saw that it was resonating with people. They noticed that I was carrying myself differently and was just happier overall. They wanted to know how I did it. That helped me realize that I was ready to commit to fitness outside of myself. I became a certified personal trainer and created Erica Fit Love, an online training platform. Now I'm able to work with people one on one no matter where they live and help them reach their own goals. (Related: How I Learned My Weight-Loss Journey Wasn't Over Even After Losing 170 Pounds)

The program I created offers a variety of workout styles including strength training and HIIT. Even though HIIT can sound and feel intimidating, I focus on scalable drills. They start with one-minute cardio intervals: either 15 seconds hard, 45 seconds rest, or vice versa. This flexibility makes my workouts great for people who are just starting out and have never really delved into fitness before. Plus the quick intervals are a great source of motivation—they're over so quickly so it deters you from quitting. My program also offers a calendar with weekly reminders and a private accountability-focused Facebook community with direct access to me to help keep everyone motivated. (Related: Joining an Online Support Group Could Help You Finally Meet Your Goals)

Hitting a Plateau

After losing the initial 122 pounds, it took me another two years to lose an additional 35-40 pounds. Some of that is totally normal—when you're going through extreme weight-loss you are going to hit a wall—but I also learned the hard way that you can't keep doing the same thing over and over again and expect the same results. I adopted a trial and error method to figure out how my body was going to reach my goal weight. What ended up working for me was reevaluating my diet and diversifying my workouts to challenge my body in ways it hadn't been challenged before. In 2018, I reached my goal of losing 150 pounds, and I finally felt like all of my efforts over the past three years had paid off. But I quickly realized that losing weight was about so much more than the number on the scale. (Related: Science Found the Best Workout to Overcome Your Weight-Loss Plateau)

My Challenges with Body Image

Despite the weight-loss, for the first time in my life, I began dealing with body image. When I was at my heaviest, I never struggled with body image. I never spoke harshly about myself and didn't feel insecure. But now? It's a daily battle. As the weight started to come off, I became my biggest critic. When you work in the fitness industry (and are on social media), everyone has an opinion and everyone is showing their highlight reel versus what's really happening behind the scenes. That's really challenging.

Even still, I didn't really understand how intense my body image issues were until I got sick. (See: How Celebrity Social Media Affects Your Mental Health and Body Image)

Three years ago I was diagnosed with Epstein–Barr virus (EBV), also known as human herpesvirus 4. EBV is a very common virus that can cause other infectious diseases such as mono and is spread through bodily fluids. I experienced serious brain fog and low-grade fevers. Even though it's under control now, it's something I will live with for the rest of my life. The biggest thing I had to learn to deal with was the feelings of exhaustion that came with the illness. It was like nothing I'd never felt before. I had to really scale back my HIIT workouts because my body just couldn't handle it. I went from doing HIIT every single day to just two-three times a week. Learning to cope with the illness combined with the change to my workout routine caused me to gain some weight. That took a huge blow to my self-esteem and brought some of my body image issues to light.

As if that wasn't enough, in November of 2018 I was diagnosed with stage 2 thyroid cancer. I underwent radiation and surgery and ultimately beat the disease, but my body went through hell and back in the process. I remember coming home from treatment, looking in the mirror and thinking: "I look terrible." (Related: My Lupus Diagnosis Was the Wake-Up Call I Needed to Stop Abusing Diet Pills)

It's something I deeply regret. My body had fought through and triumphed over so much but all I was focused on was the way I looked. It was heartbreaking, but it forced to me confront my lingering body-image issues head-on. It's something I'm still learning to deal with today.

Looking Ahead

One thing that's really quiet all the negative thoughts about my body is having conversations with myself. A part of that involved me tallying how many times I said something negative about myself on any given day. Looking at that number was a huge "holy crap" moment for me. There were some days when I said 50 negative things about myself! The comments could be a result of feeling self-conscious in my clothes or how parts of my body didn't look "perfect". Keeping tabs on my negative thoughts made me realize how quick I was to pick out my flaws and how unfair that was to myself and everything my body had been through.

Today, working out and eating healthy isn't about how awesome I look. It's about inspiring people to realize that neither illness nor your weight define you and that you're so much stronger than you think. That's what I'm trying to bring to this brand new season of The Biggest Loser as I work with contestants who are starting their own fitness journies...just like I did. (Related: The Biggest Loser Is Coming Back to TV—and It's Going to Be Totally Different)

I want them to know that truly loving and appreciating your body is an ongoing journey, and it's something you have to work hard toward every day. I also want to prove that losing weight and transforming your life doesn't have to be complicated. My story is proof that taking it back to the basics works. I didn't make any crazy, drastic changes to my life. I just took things one step at a time, and the results followed. (Related: What I Wish I Knew Sooner About Losing Weight)

Yes, there will be barriers. I, for instance, have always struggled with binge eating. I still need to plan a weekly cheat meal because if I splurge on a whim, I'm scared I won't be able to bounce back. But the key is being in tune with your personal challenges, being honest about them, and choosing to make the healthiest decisions.

At the end of the day, your health shouldn't feel like a chore. It should be looked at as an opportunity to elevate your life and motivate you to be the best version of yourself. The journey is ongoing, but if you're on the path, you're doing something right.

The Biggest Loser premieres on USA Network on January 28 at 9/8c.