Double Olympic gold medallists Helen Glover and Heather Stanning spent six years taking on the world together – now they are to race each other at the 2017 Virgin Money London Marathon.

The rowers formed one of the most successful ever female partnerships in British Olympic history, winning GB’s first gold medal of London 2012 in the coxless pairs before going on to defend that title last summer at Rio 2016.

In the four years between London and Rio, Glover and Stanning were invincible on the water, going unbeaten and sweeping up World Championship, World Cups and European Championship titles.

Stanning, 32, announced her retirement after the Rio Olympics putting an end to a golden partnership and with Glover, 30, undecided on her future, the pair has started looking at other challenges.

And the first challenge on their to-do list was the Virgin Money London Marathon on Sunday 23 April.

“I actually entered because Heather had entered,” said Glover. “We were sat in an airport together, long before Rio, and she mentioned that she was going to do it in 2017 and I said ‘well, if you are doing it, I want to do it too!’”

Stanning added: “We were flying out to a training camp and it was a bit of an off-the-cuff comment at the time, but now here we are just a couple of months from the marathon.”

Both Glover and Stanning are running for charities – Glover for the Brain and Spine Foundation and Stanning for the Royal British Legion Industries – and both are also relishing the personal challenge, as well as the opportunity to take part in an event where they are not expected to cross the line first.

But the competitive instincts still burn strong and both Glover and Stanning would like nothing more than to beat the other.

Glover said: “We will want the best for each other and for each other to raise as much money as possible for charity, but we will both want to finish in front of the other. I want her to do well – but not so well that she beats me!”

Stanning said: “Helen is definitely the more competitive! I am competitive, but she is on a whole different level.”

The two good friends have shared some of the most memorable experiences of their lives together and they are looking forward to sharing another one in London in April. They also have some idea what lies in store for them thanks to information from Glover’s mum Rachel and sister Ruth, who both ran last year.

“We were on a training camp together tracking their progress on the London Marathon website,” said Glover. “I think it made us realise just how long the marathon is. We checked on their progress, went out and did a training session, came back, checked again, went and did another session, then checked again. It was a long time! But to see my mum and sister both run and enjoy it so much made me even more eager to run this year.

“As a pair, we had so much pressure on us in the four years between 2012 and 2016. With every race it felt like we had the world on our shoulders. To think that we can now do a different kind of race and feel nothing but enjoyment while doing it – well, enjoyment and quite a bit of pain and hurting too I imagine! – is something we are really looking forward to.”

Stanning added: “It’s going to be great to do this with Helen. As time goes on, we will not see as much of each other as we have done in the past and it’s going to be nice to do this together. It’s also good just knowing someone else who is running the marathon so you can talk about it. We are going to do some of our long runs together too. We had such great times training together over the years, it’s wonderful to be doing this.”

Glover and Stanning are not the first Olympic gold medal rowers to take on the challenge of the London Marathon.

Sir Steve Redgrave, Sir Matthew Pinsent, James Cracknell, Anna Watkins and Dame Katherine Grainger have all run the 26.2 miles from Greenwich to Westminster while also running this year is Paralympian Pamela Relph who, like Glover and Stanning, won back-to-back gold medals in London 2012 and Rio 2016. Relph is running for Arthritis Research UK.