Canada's Gabriela DeBues-Stafford said she needed to leave the Bowerman Track Club "for the sake of my athletic performance and mental health" ©Getty Images

Canadian athlete Gabriela DeBues-Stafford has cited the "major distraction and stress" caused by the doping ban of former training partner Shelby Houlihan for her decision to leave the Bowerman Track Club in Portland in the United States.

DeBues-Stafford trained at the club for the previous two years, and has competed at the last two Summer Olympic Games, clocking 3min 58.93sec to place fifth in the women's 1,500m final at Tokyo 2020.

Houlihan, the US record holder in the women's 1500 and 5,000 metres, competed for the Bowerman Track Club (BTC), but was banned for four years a little more than a month prior to last year's delayed Olympics.

She blamed contaminated meat in a pork burrito after testing positive for the banned substance nandrolone, but an appeal was dismissed by the Court of Arbitration for Sport.

Houlihan has appealed to the Swiss Federal Tribunal.

In light of the case, DeBues-Stafford has opted to leave Bowerman to train at Victoria in the Canadian province of British Columbia.

"Going into the fall, I did my best to put this event behind me, and focus on all of the positives this group has to offer, as I truly did and do love this team," she explained on Instagram.

"However this event and its ongoing aftermath continued to be a major distraction and stress for me.

American middle-distance runner Shelby Houlihan was handed a four-year doping ban shortly before the Tokyo 2020 Olympics ©Getty Images
American middle-distance runner Shelby Houlihan was handed a four-year doping ban shortly before the Tokyo 2020 Olympics ©Getty Images

"For the sake of my athletic performance and mental health, I needed to move on.

"And so I am excited to have this fresh start back in Canada.

"I am now working with Trent and Hilary Stellingwerff, based out of Victoria, BC along with the entire Athletics Canada West Hub sport science and medicine staff."

The Canadian Broadcasting Corporation reported that Houlihan's continued involvement with the club was a key factor in DeBues-Stafford's departure.

"This absence of clarity surrounding the boundaries between BTC and a banned athlete is the critical reason for my departure," she said, as quoted by the CBC.

"I need to know 100 per cent, black and white, word for word, all codes and guidelines that might be relevant to me or anyone associated with me in a professional capacity in this sport."

In her Instagram post, DeBues-Stafford said that Houlihan's doping ban "almost derailed" her efforts at Tokyo 2020, and described her performance in the women's 1,500m in the Japanese capital as "a small miracle".

She added that her focus is on this year's World Athletics Championships in Eugene in the US, scheduled for July 15 to 24.