Sean Thiessen


Coach, Powerlifting Specialist


CrossFit Level 1 Trainer

NCCP (Powerlifting) – In Progress

First Aid/CPR

Sean’s path to coaching is not your traditional performance athlete turned instructor story.  Still in his early 30s, Sean was morbidly obese and showing early signs of diabetes, high blood pressure and depression. Soon after the birth of his daughter, he spent two months bed ridden on painkillers as herniated discs compressed nerves in his back. The disability of that injury, contrasted against the joys of fatherhood, presented Sean with what he saw as a life or death choice. One he could still choose to make or be forced to make later.  He chose to start a new life. After failing on his own, Sean reached out to experts in nutrition, mental health and physical fitness as he proceeded to cut 100lbs and reverse his medical prognoses. Viewing himself as a lab rat, he became a self-taught student of how the human body functioned throughout his rehabilitation and his relapses.

One of the experts Sean reached out to was CF431 owner Jeff MacGregor, then a newly minted personal trainer. Shortly after their first meeting in 2010, Jeff changed Sean’s life with a simple suggestion, “Look into CrossFit. I have a feeling it may interest you.” After being involved in amateur sport all his life, after toiling in one type of gym or another for 20 years, CrossFit’s programming, culture and community resonated with Sean. The perpetual variety, intensity and challenge hooked him; the people he met and quickly befriended kept him. He has been WOD-ing (and barking at the clock) ever since in everything from official boxes to his garage-based zombie gym.

Sean believes in bringing the strength, conditioning and team building lessons taught through CF431 to his pursuits outside the gym. Whether on the fore check in beer league hockey, or hauling a hindquarter of a freshly skinned moose through the bush or consistently shooting a 5” target at 1,000 yards (F-Class World Championship silver medal, 2013) Sean makes fitness serve his life; not vice versa.

Though Sean enjoys CrossFit’s variety, his true passion is the development and traditional exhibitions of brute strength. His favourite days involve the abbreviations “1RM” and “PR.” His favourite benchmark is The CrossFit Total. He lifts in a rage; but rests with a joke. This passion is not reserved for himself. Sean thrives off helping those around him to become stronger and to proudly display that strength to both themselves and to the world; both in the gym and in their day-to-day lives. Sean is convinced his success was only made possible by encountering the right people at the right time along his journey. Sean’s ultimate goal at CF431 (aside from a 1,225lbs Crossfit Total) is to pay that forward – to be that right person at that right time in some one else’s health and wellness journey. (