Paula Radcliffe is good at running.
Her time of 2:15:25, set on the streets of London in 2003, still stands as the women's marathon record - a race that saw her run the 24th mile in five minutes and three seconds. She's also the women's world record holder for the 10K road race distance, clocking a knee-trembling 30:21 in the same year that she set her marathon record.
So you'll understand our apprehension at heading out for "a quick run" with Radcliffe as part of a Nike Run Club Shake Out Run; a casual five kilometre run ahead of London's marathon event.
If you've been inspired to get into running, here are some pointers from the record holding Brit.
Find something to distract yourself
Running can be dull. It just can. Three hours of one-foot-then-another can leave you with an awful lot of thinking time - which can get the better of you if all you've got to focus on is how much your ankle hurts.
"Distract yourself in the moment," advises Radcliffe. "Find anything you can do to think about right now - not the distance ahead. I used to count up to 100 to take my mind off things, and then just start again. Just thinking about what number comes next, it keeps a rhythm in your head."
An obvious point, but Radcliffe puts her incredible feats (and feet) down to the importance of negative splits: running the second half of your distance faster than the first.
"In a marathon, it's always easier [on your body] if you run the second half of a marathon faster than the first half. If you run negative splits, your body uses its energy stores much more efficiently."
Be sure to top up your energy supplies, no matter the distance
If you're setting out to push yourself - particularly over 26.2 miles - you're going to need to keep your body's energy supplies topped up.
There are a wealth of diet plans out there, you just need to find one that works for you (Radcliffe typically starts a particularly carb-heavy diet four days before a marathon) - but you also need to supply your body with glycogen and fluids while you're on the move.
Even if your body doesn't feel the strain, you'll need to take on supplies early on in the race to ensure your body has something to burn through come mile 21.
If you're going to run a Marathon, make it London
Berlin might be better suited to 'quick' times, but Paula's favourite 26.2 mile distance is on the streets of London.
"Every marathon in its own way is unique, but me being British, it's got to be out on the streets of London - mainly due to the support that I had. Around London you know you're in one city the whole way; when you're in New York it's like you're running through five different countries as you go from borough to borough throughout the route."
While ballots for the 2017 race open on 2 May, you've still got a chance to run through the UK capital in the Royal Parks Foundation Half on 9 October (charity and corporate spaces are available here).
Also, you're going to want to pick a route that doesn't involve too much cursed concrete.
"A lot of the road surface of New York is concrete rather than tarmac, and that's much harder on your legs. The bridges are also hard - long drags that can sap you."
No, you don't have to dress like a tit to enjoy a run - but having "fun" is crucial to getting the miles in.
Find a bunch of like-minded nutters at a local run club (Nike has a list of them) and develop your new addiction.