KELLY SOTHERTON says one missed drugs test "doesn't mean you are doping" and that the testing system is "not as easy as people make out".

According to reports, Mo Farah missed two tests before twice winning gold for Team GB at the 2012 Olympics.

It was claimed the second one came at Farah's home in February 2011, when he claimed not to have heard the doorbell.

UK anti-doping chief executive Nicole Sapstead said it is "not common" for an athlete to miss a test.

Sapstead said Ukad "will do everything to help athletes understand their reporting requirements", but added that "forgetfulness is not an excuse".

However, Olympic medallist Sotherton said: "Sometimes your mind isn't 100% as all you're thinking about is training."

Nine UK athletes missed two tests in the same year as Farah did.

Sotherton, 38, said top-level athletes are tested up to 20 times a year and have to know three months in advance where they are going to be.

"This could be when you are on holiday – you still have to give your hotel details. You are never free of drug testing," said Sotherton, who won heptathlon bronze at the 2004 Athens Olympics.

"I've been tested nine times in six weeks before – at my house, at the track, at my partner's house. I can understand how a missed test could happen, and if you make a mistake once, most athletes learn from it.

"But a missed test doesn't mean you are doping. It may mean you have been a little bit careless – that doesn't make you a drugs cheat.

"I was very organised and I made a slip of a number by one day – that's how a missed test can happen."

Farah's gold medals in the 5,000m and 10,000m at London 2012 were among the defining moments of the Games.

At the time, UK anti-doping (Ukad) rules stated an athlete who missed three tests in any 18-month period could face a ban of up to two years.

That meant Farah could have been ruled out of his home Olympics with one more breach of the rules.

The rules have since been amended and now athletes who miss three tests in a 12-month period can be banned for four years.

Team GB's 2012 Olympic 400m champion Christine Ohuruogu was given a one-year ban in 2006 for missing three out-of-competition tests.

The independent disciplinary committee which heard her case admitted it was a "harsh sanction" for someone who had "no intention of infringing anti-doping rules".

The ban was described as a "much-needed wake-up call for athletes" by then UK Sport director of drug-free sport, John Scott.

Sapstead believes that UK athletes are "incredibly supportive of the whereabouts system" despite some frustration with the requirements placed on them.

She said: "They understand that what the whereabouts system does is it not only protects them, it protects the sport, it demonstrates that they're making themselves available for testing and it reassures the public that the people that they hold in high regard in sport are being tested and properly scrutinised."