It's probably too strong a statement to say that without exercise, Chris Cornell -- lead singer of 1990s grunge band Soundgarden -- wouldn't be around anymore.
But it's pretty close.
"For years, I wasn't feeling good about myself," said Cornell, who formed the Seattle band in 1984. "My head wasn't clear. I was doing nothing productive."
When Soundgarden hit it big with the 1994 album "Superunknown," Cornell lived the typical rock star lifestyle: drugs, alcohol and no sleep. That was no different from other Seattle bands such as Nirvana, Alice in Chains and Pearl Jam.
Then, as with other bands, internal strife torpedoed Soundgarden in 1997.
"I decided I needed to work on my brain and not just my body," said the 48-year-old Cornell. "I figured if I focused on my brain, that everything else would fall into place."
It wasn't an easy road as Cornell struggled to give up drugs and alcohol and focused on solo work and creating Audioslave (2001-2007). He then went solo again and reunited with Soundgarden in 2010.
These days, the band is touring off its sixth studio album, "King Animal." Tuesday night, Soundgarden is performing in New Jersey.
Cornell, who rarely gives interviews, talked exclusively with Playbook about exercise, music today and life on the road.
What does being physically fit mean to you?
"It means I can do whatever I want without having to worry about it."
You've been in the music business for years. How fit were you growing up?
"I remember as a kid that I was always physically fit. In the United States, workouts tend to focus on body image and how you look. For me, it's really all about the brain. I think back to my childhood, and I remember running around as a kid. We were all running around then. It wasn't about getting into shape. It's just what we did."
So what happened when you hit it big as a rock star?
"It goes back to the brain. It never felt right to me unless I was working out. If you're a psychiatrist, I assume it was about self-image. I don't like being out of shape and I needed to focus on my work ethic. I remember before hitting it big when I was working in all these odd jobs that I would do pull-ups in the back of kitchens that I was working at. You never know about availability or time or space. I would just wedge it in. I then had those periods of my life when I was inactive. I wasn't feeling good then. I finally forced myself to get out and do something."
So you decided to get back into shape. What did you do?
"I prefer not to use any machines. I focus a lot on cardio, which is what I do when I'm on stage. I also am into isometric workouts. When I'm mentally distraught, I work out. I'm always hiking or walking these days. And I still love my mountain bike."
So now that you're back on the road, do you get to work out?
"At this point, I'm performing three shows in a row for more than two hours at a time and then I'd get a day off. That is my workout. I don't do anything on the off days so I can prepare for the next show. I need that day off to rest to be able to sing that long."
You've been on the road for more than 20 years. What does touring in 2013 mean to you?
"I feel pretty much that I can do whatever I want. You need to be focused and get to that place. What's important is to get into shape and then not to have to worry about it. I don't want to get on stage and not being able to do something. Not being physically fit doesn't work for me."
What is today's music business like?
"I consider where my place in the world of music is now. I've had a long career and I want to continue to have a long career. The way to do that is not to go away. Starting out in music today is a lot different. The methods of gaining an audience and communicating with an audience and how to monetize that audience is more challenging. Thankfully it's very different for us. We already had an established career and people know who we are. It's like the old method of attracting an audience."
Is being out there still fun?
"I don't think it is as much fun as [when] we were first did it. There is a lot of paranoia in this world. We used to travel around in a van and play these small venues, often in front of nobody. It really was hit or miss. We needed to get enough money to get a hotel room at the next place. That was more like what rock 'n' roll really is."
But you wouldn't have done anything differently, except maybe quitting smoking and drinking earlier.
"I was going to be a musician, no matter what it took. I supported myself with blue-collared jobs so I could write music and be in a band and play shows. I even got into an underground art scene. I was going to do whatever. I just had to pay rent and buy guitar strings. I look at my situation and realize how extremely fortunate I am that I can support myself and my family today. I'm getting to do what I love."