Fitness is Personal to Me

I founded Black Dog Fitness to help others who are suffering from mental health conditions.

I struggled with an undiagnosed mental illness for years.  I finally realized what was wrong when I saw a video called “I have a black dog and his name is depression.” That was me. I had a black dog.

I have Depression.

When I finally got professional help, one of the first things my psychiatrist told me was that I had to get back to exercising.  Before she would even consider medication, I had to get back into the gym. Today, regular intense exercise is a non-negotiable part of my schedule and is essential for balancing the demands of being a husband, a father, a business owner, and someone who suffers from depression.

Zach Guza

Certified Personal Trainer and Parkinson’s Disease Exercise Specialist in Knoxville, TN.


  • United  States Air Force Academy graduate
    • Air Force Officer & Helicopter Pilot
  • Certified Personal Trainer WITS Education
  • Brice and Blair’s Dad (the ultimate workout)
Zach Guza knoxville personal trainer, knoxville boxing instructor


I don’t have perfect abs.  I like to eat.  I have a drink occasionally. I LOVE coffee and pizza.
I am pretty normal but I know that regular exercise is about more than “getting huge” and looking tone.  It can be the difference between life and death.

Knoxville’s only Gym for people fighting Parkinson’s disease

Black Dog Fitness is also personal to me on another level. My dad had Parkinson’s Disease but he was never told that exercise would help him live longer, happier and healthier.  He suffered a steady decline until his death in 2013. 

Hundreds of studies have shown that exercise can slow, stop, and even reverse the symptoms and progression of Parkinson’s Disease.  I wish that my dad would have had a place like Black Dog Fitness to exercise.

I started Black Dog Fitness and Rock Steady Boxing Knoxville so that no one else has to go through what my dad went through.

In the News

I’ve been fortunate to have been featured and interviewed by various outlets.
Here are a few of the most recent.


a home-health series with The Parkinson’s Foundation where I discuss tips & movements to promote posture & strength


an interview with The Davis Phinney Foundation on becoming a Parkinson’s Disease Exercise Specialist


an interview and conversation with Dr. Carole Myers about the benefits of physical fitness for mental health


In October of 2012, the World Health Organization put out a video called “I had a black dog, his name was depression.”  It is a video version of the 2005 book I Had a Black Dog​ by Matthew Johnstone.  

The instant I saw this video, I realized that the pain and torture I had been through had a name, it wasn’t my fault,  and it could be treated.

Please contact me if you are struggling with depression.  

I have been in the deep, dark “No One Cares” mode. I still go there occasionally but now I know that there is a way out.