LONDON, UNITED KINGDOM (Reuters) - British astronaut Tim Peake said on Wednesday (April 20) that training is going well for the London Marathon, which he will run aboard the International Space Station (ISS).

Peake made the comments in a question and answer station from the ISS, during which he showed off a harness that keeps him bolted to the treadmill on which he will run.

"I don't think you can ever do enough training for a marathon. But I've certainly been putting in the miles on the T2 treadmill - that's what we call it up here on the Space Station. And I've done a couple of half marathons and a little bit longer distance than that as well. So I'm confident I can get on and run the marathon on Sunday. But I'm sure there will be a few points where I'm wishing I did more training," Peake said.

Peake said the excitement of the actual marathon course for Sunday's (April 24) event will keep him motivated on race day.

"Firstly, I've got the Run Social app, so I'll actually be looking at the route I am running, and I'll be running along everyone else who's running the digital version of the London Marathon. And also, hopefully, I'll get the tele sent up to the Space Station as well, so at times I'll be able to see what's going on with the real race down in London, which will be a huge boost to me to be able to know that I'm running along everyone down there," he said.

Peake said he expected the weightlessness of space to help him recover from the grueling 26.2 mile (42 km) run.

"In terms of recovery from a race or from running training, actually weightlessness is one of the perfect environments because the moment you stop running and the moment you get off of that bungee system , your muscles are in a relaxed state. And I do think that we recover faster up here from any kinds of aches or strains. And muscular problems I think do recover quite quickly up here," he said.

Peake said he was hoping to run the marathon in 3.5 to 4 hours.