In his heyday, Johny Hendricks was one of the greatest welterweights alive. A former UFC champion, Hendricks emerged as one of the 170-pound division’s most ferocious figures from the beginning of his title run in 2009 to the onset of his late-career slide in 2016. Over that time, Hendricks notched a litany of a big wins — Robbie Lawler, Carlos Condit, Martin Kampmann, Matt Brown, Josh Koscheck, Jon Fitch — and nearly dethroned one of the greatest fighters of all-time, Georges St-Pierre, in a contest that is still debated today.

But Hendricks walked away from the sport of mixed martial arts earlier this year at age 34, announcing his retirement following a 1-5 slump that saw him suffer three brutal knockouts, miss weight three separate times, and ultimately abandon 170 pounds for the middleweight ranks after it became apparent that the cut to welterweight had become untenable. It was an inauspicious end to a once-celebrated career, to say the least. And Monday on The MMA Hour, Hendricks admitted that he believes USADA’s presence in the UFC played a major role in how the final chapters of his run played out — but not in the way some would expect.

“I think USADA’s a great thing for the athletes, because it’s making people be clean, right? I took 26 tests, never failed one of the them. And that was in two years; I took 26 tests, never failed one of them. But what hurts the MMA aspect is that you can’t [use] IV bags,” Hendricks said Monday on The MMA Hour. “So, I’m a bigger welterweight, I walk around at 210. I’ve done that since I was 19 years old, walk around at 210, and the IV always brought me back. It helped me get back to life, it helped me get to where I didn’t feel like I cut weight. And once USADA come into play, I had to start walking around like 190 at best, and as you can tell, I do carry a lot of weight ... and that’s sort of one reason why it just made it that much harder to make weight at 170.

“I’m just not in the sport to just be in a sport. Does that make sense? I can do other things. If I’m going to do it, I want to be the best, and I know welterweight is my best. That’s where I should be. Now, like I’d said, I loved the fact of USADA and I loved that you do the random drug testing. I just wish that, they have a lot of people that show up at these meets — you want to do an IV, have them test you every day. I’m perfectly fine with that. You show up Monday, you get tested. Tuesday, you get tested. Wednesday, you get tested. Thursday, if you have any pee left, you can get tested on Thursday. They’re there testing the IV bags, they’re doing everything like that, and I think you can bring back IVs, because I think there’s a lot of people that really used the IVs to help them fight better.

“Once you took that away, you started to see some of these guys, they either had to move up or they stayed at their normal weight and they didn’t perform like they used to.”

The UFC’s partnership with USADA started in the third quarter of 2015.

Hendricks, 35, racked up a 12-3 Octagon record in the pre-USADA era, highlighted by a title run that saw him capture gold with a ‘Fight of the Year’ victory over Robbie Lawler in 2014. However, Hendricks went 1-5 over his next six contests after the USADA program began, and at one point missed weight three times over a four-fight span. He had weigh-in scares prior to USADA, but never had actually missed weight up to that point. And Hendrick said Monday that USADA entering the sport and immediately banning IV use to assist with weight cutting became a major blow to his ability to compete at the highest level.

“I tell everybody, go run 26 miles, take an IV. The next day you’re going to be sore, but guess what? You feel like you can run again,” Hendricks said. “It’s an amazing thing. All the vitamins, all the minerals that you’re pulling from your body, irons and stuff like that your body really needs to compete at a high level, definitely whenever you’re fighting in the UFC, you need those back in your muscles. A perfect example: Without them, I think I was fighting at maybe 50 percent. With them, I was fighting right around 90 percent, because my body was able to recover after that hard weight cut.”

Hendricks said the accumulated damage from his repeated weight cuts became an overwhelming force in his life after a year without IV use. He said things came to a head following his Dec. 2016 fight against Neil Magny. That fight proved to be his final outing at 170 pounds, and his body did not handle the stress of the situation well.

“After the last time I fought 170, my kidneys shut down. I ballooned out,” Hendricks explained. “So, let’s see, I fought on Saturday. On Sunday night I got home, I was 219, and I blew up like a balloon. My doctor was like, ‘Hey, you need to go to the hospital.’ I was like, I know exactly what’s going on, my kidneys shut down. And I guess it went on for about four or five days. On Thursday, they rebooted, and whenever that happened, I went from 219 to 199 in like 24 hours, and I didn’t work out or nothing. That’s when I was like, ‘You know what, I’m going to kill myself.’ And that’s the thing, with IVs, the damage that you do by cutting weight, [the IV] helps you not kill yourself, because like I said, all that stuff that’s important to your body, you can’t get it back in 36 hours. You can’t get it back in 48 hours.

“But with an IV, it goes straight into your veins, it goes straight into your muscles, in your organs, and it sends [everything] exactly where it needs to for you to recover the best you can. That’s why in every sport, what do they do? In every sport, if you’re hurting or you’re this or you’re that, they give you IVs. They’re a huge part. I remember back in the day, I liked to take them on Wednesdays. I’d take like a half of a bag on Wednesday, just so that way it’d keep me from getting sick, it helped where I could train harder — so on Wednesday, I would start fading on my training, and then I would take an IV bag in the middle of the day, I could train hard on Wednesday night, Thursday, Friday, and it was like a brand new me.”

It’s worth noting that IVs aren’t only banned by USADA. They are considered a prohibited substance by the World Anti-Doping Agency (WADA), and thus are considering a prohibited substance by many state regulatory bodies that follow WADA code, including the state athletic commissions in Nevada, California, and New York.

Hendricks’ MMA career ended last November with a second-round TKO loss at the hands of top middleweight prospect Paulo Costa at UFC 217. Hendricks said he briefly considered exploring a move to Bellator or another promotion outside of the UFC, but by that point he was simply ready to move on to the next chapter of his fighting life. He’ll now do so on Nov. 9 when he makes his bare-knuckle boxing debut against one-time Bellator title challenger Brennan Ward at World Bare Knuckle Fighting Federation’s inaugural event, and all things considered, Hendricks said he is happy and content with his decision.

“I just got to a point where sometimes it’s how much you’re going to talk to get something,” Hendricks said. “How bad does the press want to follow you? How much are you going to talk trash about this guy, this guy, this guy, to get the fight? And for me, I’ve always been the guy that, talking trash is easy, but for me, I just wanted to try something [different]. Realistically, I’ve wanted to try out boxing for a little bit, and whenever the bare knuckle TV, they came after me, they talked to me, I was pretty excited because I want to see how my hands are.

“I’ve been wanting to find out for a while: How good is my striking? Because I’ve gone with some very, very talented boxers here in Texas, and it’s just been a dream of mine. I’ve been a huge boxing fan all my life. I grew up watching (Mike) Tyson, I grew up watching the old classics, and that’s sort of where my next pull led me.”