The documentary alleges that Salazar was involved in doping American Galen Rupp, the 10,000 metres silver medallist at the 2012 London Olympics behind Farah, in 2002 and reported that some of the coach’s methods included the use of banned steroids and unethical practices.

BBC investigation claims Alberto Salazar was involved in doping US athlete Galen Rupp in 2002 http://t.co/MLg7u02pQT pic.twitter.com/3QJ033aDSc

— BBC Breaking News (@BBCBreaking) June 3, 2015

There is no suggestion that British athlete Farah has broken any rules and the Olympic 5,000 metres and 10,000m champion told the BBC: “I have not taken any banned substances and Alberto has never suggested that I take a banned substance.

“From my experience, Alberto and the Oregon Project have always strictly followed WADA rules and if there is ever a question seek guidance from USADA (United States Anti-Doping Agency) to ensure they are correctly interpreting WADA’s rules.”

Salazar and Rupp deny any wrongdoing but the BBC programme showed Rupp’s blood chart to Howman, who said he was “disturbed and very disappointed” by the information.

Speaking from WADA’s headquarters in Montreal, Howman told Press Association Sport: “We are trying to get access to the BBC footage in Canada.

“I do not know how easy that will be – but that’s what we are undertaking at the moment.

“It’s probably sensible not to say too much until we have seen the footage of the programme, but if the allegations are as serious as they have been reported then they need to be investigated beyond a national level.”

Salazar, who won the New York marathon three years in a row between 1980 and 1982 and was also a Boston marathon winner, has worked with Farah since 2011 and has coached the Briton’s training partner Rupp for 14 years.

Mo Farah races 1500m in Birmingham on Sunday at a meeting run by an organisation that uses Salazar as an advisor. Interesting few days ahead

— Jason Henderson (@Jason_AW) June 3, 2015

His coaching philosophy involves intensive training and the use of the latest scientific techniques.

While no NOP athlete has ever failed a drug test, the BBC says at least seven athletes or staff associated with the Portland camp have gone to USADA with their concerns.

USADA has neither confirmed or denied investigations into the NOP, but allegations have been made by a number of the camp’s former athletes and staff.

Steve Magness, who was Salazar’s number two at the Oregon Project in 2011, told the BBC he saw a document showing Rupp’s blood levels, which said the athlete was on “testosterone medication”, and that he had been given the banned anabolic steroid testosterone in 2002 at the age of 16.

Since 2003, WADA rules have stipulated that athlete support personnel involved in doping someone as young as 16 could be liable for a lifetime ban.

“When I saw that, I kind of jumped backwards,” Magness said. “Testosterone is obviously banned... everybody knew that.

“When I looked a little further I saw it was all the way back in high school - and that was incredibly shocking.”

Magness, who left Nike in 2012 and later went to USADA with his story, said when he questioned the coach about the document, Salazar said it had been a mistake.

Salazar declined to be interviewed for the programme but he told the BBC in a statement that the legal nutritional supplement Testoboost had been incorrectly recorded in the document as “testosterone medication”.

“Allegations your sources are making are based upon false assumptions and half-truths in an attempt to further their personal agendas,” Salazar added.

“I believe in a clean sport and a methodical, dedicated approach to training and have never, nor ever will, endorsed the use of banned substances with any of my athletes.”

Rupp, one of America’s most drug tested athletes, strenuously denies ever using testosterone or testosterone medication.

“I am completely against the use of performance enhancing drugs,” said the 29-year-old current American record holder at 10,000m.

“I have not taken any banned substances and Alberto has never suggested that I take a banned substance.”

The programme also heard claims testosterone was seen on several occasions by athletes and staff and that Salazar tested testosterone cream on a human subject, to find out how much it would take to trigger a positive drugs test.

It is also alleged Salazar encouraged the use of Therapeutic Use Exemptions which allow athletes to use a banned substance or method to treat a legitimate medical condition.

High-profile US distance runners Kara and Adam Goucher, both former NOP athletes, claimed Salazar tried to get a TUE for an intravenous drip for Rupp ahead of races.

However, Salazar said: “I have never coached an athlete to manipulate testing procedures or undermine the rules that govern our sport...and follow the process for TUEs.”

Rupp said the only TUEs he had applied for and received were related to his asthma medication and treatment of severe flare-ups for the condition.