Ternion Fitness & Athletics
Sport Psychologist Sly Walters MSc at the Ternion facility in Streetsville Mississauga
Est. 2014

Train the body. Sharpen the mind. Own the game.

Sport Psychologist Sly Walters

Sly Walters MSc is a Sport Psychologist and Certified Athletic Trainer based in Streetsville, Mississauga. Over 19 years of coaching across Olympic, MLS, NHL, and Canadian national team athletes. Founder of Ternion Fitness & Athletics. Available for 1-on-1 athlete work, team engagements, and speaking.

Book a ConsultationMental performance coaching
Canada SoccerCanada BasketballOBADPCDSBFeatured on TSNEst. 2014
Portrait of Sly Walters MSc, Sport Psychologist and founder of Ternion Fitness and Athletics in Mississauga

◆ Sport Psychologist + Founder

The whole athlete
Coached by one person

Sly founded Ternion Fitness & Athletics in 2014 to deliver integrated whole-athlete performance training in Mississauga. The premise was simple: most facilities address one piece. The body in one place, the mind in another, recovery in a third. Athletes deserve better than fragmented programming.

As a Sport Psychologist and Certified Athletic Trainer with 19 years of experience working with Olympians, MLS players, NHL players, and Canadian national team athletes, Sly brings the same coaching standards to every client. Whether you are a rostered provincial athlete or an adult who refuses generic gym programming, the methodology is the same. The intensity scales to your goals.

“I have seen athletes achieve greater heights by changing their psychological state alone.” That is the leverage of integrated mental performance work, and it is the thesis Ternion was built on.

Work With Sly
19

Years coaching

MSc

Sport Psychology

CAT-C

Athletic therapy

TSN

Featured 2026

What Athletes Say
About Working with Sly

01

Tanvi Malik

Personal training client

“Training with Sly has been a game changer for me and my husband. We challenge our bodies in every session with the dynamic training, but more than that, it has developed a more resilient and positive mindset. If you want to push your body and mind to your maximum potential, this is the right place.”

02

Marco Paoletti

Competitive soccer player

“Highly recommend for athletes of any age in any sport looking to reach that next level. I have seen a huge difference in my strength and conditioning and it has helped me prevent injuries for soccer. Best training I have had by far.”

03

Anika Sproxton

Long-term Ternion athlete

“Through all my years of working with various trainers, I can assure you Ternion is top tier. Their devotion to everyone makes the aura feel as if we are family. I have never been one to consider mindfulness but now that I have, there is no going back.”

◆ Where to Work with Sly

Two services
Same coach

Mental Performance Coaching

Sport psychology applied directly. Focus, confidence, pre-competition routines, recovery from performance anxiety.

See the service

Athletic Training

Strength and conditioning, speed and agility, sport-specific development. Programming integrated with mental performance work.

See the service

Frequently Asked Questions

Who is Sly Walters?
Sly Walters MSc is a Sport Psychologist and Certified Athletic Trainer. He founded Ternion Fitness & Athletics in Streetsville, Mississauga in 2014 to deliver integrated whole-athlete performance training. Over 19 years of coaching across athletic training, mental performance, and high-performance sport.
What does a sport psychologist actually do?
Sport psychology applies psychological science to athletic performance. Sly works with athletes on mental skills like focus under pressure, pre-competition routines, confidence, and recovery from performance anxiety. The work is performance-focused, not clinical. If a client needs clinical mental health care, Sly refers to qualified providers.
Who does Sly work with?
Olympic, MLS, NHL, and Canadian national team athletes through 19 years of practice. Provincial and national-level youth athletes through Ternion's athletic training and mental performance programs. Driven adults applying performance psychology to professional and personal goals. Teams and academies through workshop and season-long engagements.
What is Sly's credential set?
MSc in Sport Psychology, Certified Athletic Trainer (the practitioner credential, not to be confused with Certified Athletic Therapist CAT-C which is a different scope). The combined credential set lets Sly program physical training and mental performance work as one integrated system rather than two separate services.
Can I book Sly for a one-off speaking engagement?
Yes. Sly takes speaking engagements at corporate events, academies, schools, and sport organizations. See the Teams and Organizations page for engagement formats and to submit an inquiry.
Work directly with Sport Psychologist Sly Walters MSc in Streetsville Mississauga

Train the body. Sharpen the mind. Own the game.

Work directly with Sly

1-on-1 sport psychology, integrated athletic training, or a team engagement at the Streetsville Mississauga facility.

Book an AssessmentCall (905) 828-7298