In the gym he was the strongest. The most disciplined. The hardest worker.
Then suddenly he wasn't.
Shanahan was 28 years old and weeks out from his first bodybuilding competition when he suffered a stroke that would change his life forever.
Now, more than three years into recovery, he's sharing his story in hopes that others will think twice about using steroids.
"I knew it was important to take care of your body but never thought steroids would cause a stroke," the 32-year-old personal trainer said. "Had I known it would be like this, I absolutely would have done it differently. I never would have done steroids."
Lifting weights played a major role for Shanahan -- from Little League to high school sports -- when he was growing up in Toms River.
I wanted to be as strong as I possibly could
He moved to Ridgefield Park after high school to start working at a kids gym in Rutherford and then as a personal trainer at Retro Fitness Hackensack the following year.
The more time Shanahan spent in the gym, the more serious about bodybuilding he became.
His personal goal was simple: to be stronger than he was the day before. It was his high.
"You always want to look better and be stronger," Shanahan said. "But it was never enough."
Steroids were something he hadn't considered -- until then. Although he knew he'd be risking his health, the rewards seemed worth it.
"When I was 19 and 20, I said I'd never inject myself," he said. "And then I turned 26 and that all went out the window."
Shanahan first tried steroids in 2011. That same year, he was diagnosed with ulcerative colitis.
He stopped for awhile but started again in late 2013 -- testosterone, masteron and trenbolone. This time it was excessive.
Trenbolone -- or tren as it's commonly called -- is extremely exciting to some but also extremely dangerous, Shanahan said.
Steroids.com suggest 100mg per day as an advanced trenbolone dosage -- 700mg per week maximum. Shanahan was injecting himself with between 300mg and 600mg twice a week -- almost 300mg over the suggested weekly dosage.
Nearly a year later, in February 2015, Shanahan was on track to compete in an April bodybuilding show. He looked and felt phenomenal. He was weighing out and measuring all of his food, had his meals perfectly timed and even started tapering off of the steroids.
Then came a colitis flareup that sent him to the hospital for a week. Doctors put him on a new medication and he returned to life as usual -- lifting, eating and preparing for his show.
Fate had other plans.
Shanahan was laying in bed one day mid-March, almost two weeks after being released from the hospital, when he suffered a seizure.
"I came downstairs and my balance was off," he recalled. "I knew something was wrong. It was a totally new feeling. I thought I was having a panic attack."
He called his gastroenterologist to see if maybe it was the new medication, but the physician told him to go to the emergency room immediately.
The last thing Shanahan remembers was his family rushing him to Hackensack University Medical Center, where he collapsed, suffering another seizure and a stroke.
He spent the following three weeks in a medically-induced coma undergoing at least three brain surgeries.
When he finally awoke, Shanahan had lost most of the motor function on his left side.
I should have died
Although steroids likely caused the stroke (with a 1-2 percent chance they coincided with colitis), physicians said Shanahan's physical shape -- his lean muscle mass -- was what saved him.
"I remember the doctor looking at my mom, pointing at me and saying: 'That's a miracle right there'," he recalled.
"I should have died," Shanahan said. "On a scale, the stroke I suffered was one of the worst, a 9.45 out of 10."
Shanahan faced a long road to recovery. Although he never lost his memory or speech, he had to relearn the most basic functions.
Shanahan eventually was transferred to the Kessler Rehabilitation Center in Saddle Brook, where the real work began.
"I had to relearn to eat," he recalled. "My right arm had jerks at first. My left eye was impaired peripherally and I had to relearn to walk. That took about six months."
Shanahan's left arm is still completely stiff. With his one good arm he holds a cane.
"My independence is gone and that kind of sucks," he said, "but it's one of those things you kind of have to come to grips with. At some point you kind of get used to day-to-day things. You realize this is life now."
The idea that he could be better tomorrow was what got Shanahan working out in the first place. It remains his motivation.
"No matter what I do, I want to be better than the day before," he said. "I read a lot. It's therapy, It's knowledge. I'm hoping one day I'll improve to a point where I'm more functional, but I never beat myself up about it."
Instead, he uses his own circumstances as a cautionary tale.
"Fitness is the best addiction," Shanahan said, "as long as you don't do anything stupid."
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