Corey Taylor has been a personal trainer for six years, but his most recent challenge may have been his most unusual yet as he gained weight — and was challenged to lose it all and get back into shape — for a reality series appropriately titled Fit to Fat to Fit.

As part of the challenge, the six-foot tall trainer, 28, went from 204 pounds (13 percent body fat) up to 261 pounds (50 percent body fat) back down to 199 pounds (9 percent body fat).

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Ahead of his episode of the reality show — which airs tonight — the Atlanta native opened up to In Touch about his experience gaining (and losing) the weight.

Check out what he had to say!

What was your diet like before?

Before I started this experiment and started on this project, I had spent a year as a pescatarian; so basically no red meat, no poultry, just seafood and vegetables. It was cool, great, interesting, then in 2014 I was [a] doing vegetarian [diet]. So entering this project I wasn't eating any meat at all. A normal breakfast for me would have been a big protein shake and a fruit parfait that I'd make at home with Greek yogurt and granola. By mid-day snack, I'd have a veggie wrap from Publix with kettle chips. Then middle of the day, I'd have something simple like egg whites and sweet potato and then another shake and then back at home for dinner, it would be a smorgasbord. Me and my roommate were really creative, we were doing [mashed] potatoes out of cauliflower, green peppers, just having fun with this lifestyle.

How'd you look and feel?

I was lean, I had more energy, my hair and fingernails were growing like crazy. It was great.

What was your workout regimen like?

I'm crazy! I love life. Before the project started, I'm literally working people out from 5 a.m. to 9 p.m. and I’m going 120 miles an hour with my tongue out. It's fun for me. Workout-wise, I’m doing at least an hour of cardio before 9 a.m. whether it's running with parachutes or maybe doing jump rope with ankle weights or running with a gas mask thing making breathing hard. By noon I would have gone to a park and done some short videos of my working out doing an instructional video doing pull-ups and push-ups. Or maybe climb a mountain. We have some cool stuff down here in Atlanta. By the evening I'd work out in the gym, doing heavy weights. So during the time I was trying to bulk, loading up the weights doing heavy sets. And at night, I would have my boot camp and the boot camp is 45 minutes of interval training and it's non-stop and I’m at the helm. I try to kill myself every time we do the class. So I was burning easily upwards of 5500 calories a day. Talking steps, I was getting about 22,000 steps a day — constant activity and constant motion. I couldn't have gained weight even if I wanted to because I was always busy and always on the go all the time.

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** Did you ever have a cheat day or indulge in anything?**

I always tell my clients that you know you've reached the pinnacle when your cheat foods are still healthier than most people's healthy foods. I retrained my palate. I don't like refined sugar I like natural sugar. My thing would be I'd go into the kitchen and dice up five apples and put some milk and peanut butter over it with granola, flax seeds, cinnamon and raisins and maybe take some graham crackers to crumble over it. Make my own versions of sweet fixes using things that weren't nearly as harmful as the stuff I was about to eat over the course of the project. An indulgence for me was still healthy. And I always just ate until I was full, never over did it.

Did you feel like you were depriving yourself?

I felt like I was at my peak. I felt like I had reached a point, physically, that I had never reached before. Honestly it was like renaissance for me. I was dunking, I think I was 26 years old and was finally able to dunk, so that excited me. This training thing is really changing me! I had definition in places I had never seen before; I was faster than the fastest I had ever been. Life began to be something new for me. It was an experience for me. I was convinced that it was the best time of my life because it was the best I'd ever felt in my life. Every day was a day in the sun. I do believe the confidence came from that Corey, who was at the best shape of his life. I felt like I could do anything.

So why did you do the experiment?

Because I thought I could do anything! Maybe gaining 45 percent body fat wasn't so crazy. I could do it and then undo it. It was a challenge.

corey taylor
A&E

** Did people treat you differently at your fittest versus your fattest?**

Okay I'm telling you the truth, it might be surprising, but I guess I'm so secluded in my lifestyle that I wasn't seen as much, but even so, when I was my perception entered the room before I did — "He's a hard worker." During the project, I was going out a lot. If I didn't have fitness in my life I would be broke and out everywhere! I was going to day parties, lounges etc. and I found that I got way more attention from the ladies when I was fatter than when I was fit! I don't know if it's because we're in the South and there are more guys with stomachs than six-packs. I considered myself sloppy, I considered myself out of shape, but the guys were calling me "Big Man," "Hey Big Man, over here Big Man" — it got on my freakin' nerves and then the girls, maybe it was because they didn't feel intimidated or I was more approachable, but that was the biggest difference. I was more approachable. But when I was fit, I felt like I was left alone. Maybe it's a regional thing!

How did this experience change you?

It forced me to let my pride and ego go out the window. A young man in his prime, how is that possible? It forced me to do that and I didn't know I could. I discovered so many more sides to myself that I didn't know existed. I didn't know who good of a writer I was, I knew I was a good communicator, but when I couldn't show my body I was forced to talk about what it takes to live healthy. I was forced to talk about the things I wanted to just show you. I forced me to hone in on those. So now I am able to get to people on a deeper level now. It changed how I see fitness. It's so much more than the body you have. It's your appreciation of yourself and your life. It's about being healthy. And spiritually and emotionally, I grew up because I went through something I couldn't really prepare for and I had to do it alone. Of course I had friends and a team in my life, but I was alone in a lot of this. I'm so much more than a trainer, call me a life coach, call me a specialist, a personal trainer doesn't even encompass it. It's not about me making you do jumping jacks. You've got to get into the "why" and this project forced me to do that.

To see Corey’s journey, check out Fit to Fat to Fit tonight at 10 p.m. on A&E!