The 'America's Got Talent' star opened up to ET about how he's feeling following his back-breaking injury last August.
"The first four weeks were the hardest," Cowell, 61, recalls. "Because you feel kind of helpless, and it was the first time in my life I've ever felt helpless."
"Then you're bored and frustrated, and I was in so much pain, if I'm being honest with you," Cowell adds.
The TV personality and media mogul broke his back in several places while riding an electric bike in the courtyard of his home back in August.
The injures required an extensive, six-hour spinal surgery to correct, and quite a lot of recuperation time to heal properly. However, Cowell said that after taking the steps to recover, much of his pain dissipated as if it were a miracle.
"Just like the doctor said, you hit this kinda seven, eight-week mark, and it's like it never happened. I mean, literally like that, so there were a lot of pluses," Cowell shares. "And I didn't catch COVID, so I was lucky."
In fact, Cowell said that in spite of the pain, his injury has actually led to him living healthier and treating his body better than he had been before the accident, and he's in a better place now physically than he'd been.
"I'm healthier now than I was a year ago because of this back injury. One of the things you've got do is so much exercise, to kind of, like, heal," Cowell explains. "So I have to walk, like, five, 10 miles a day, so I actually feel better than I did a year ago."
Cowell also credits his girlfriend, Lauren, and their 7-year-old son, Eric, with helping him recover and keeping his spirits up when he was down.
"I never would've had this kinda time with Eric before," Cowell shares. "He was amazing, because I was very embarrassed when I got home from the hospital... And he came in, because I've got all these metal rods in my back and screws and he went, 'Dad, you look like Iron Man.' And I went, 'Yeah, I'm like Iron Man, yeah."
While he was dedicated to his recovery, Cowell also admitted that some habits die hard -- especially his love for water sports. Four months after his surgery, Cowell was spotted on vacation in Barbados, riding on a jet ski.
"The doctor said to me, 'There's one thing you cannot do, Simon. You cannot go jet skiing when you're on holiday!' By day two, I was jet skiing again," Cowell recalls.
Needless to say, Cowell will be back behind the judges' table when season 16 of America's Got Talent premieres later this year.
AGT is having a last-chance audition for performers who still hope to make it in this season. Those interested can find more info here.
Check out the video below for more on Cowell's injury and recovery process.