Adventurer Sean Conway is pushing his body to new limits as he attempts to complete the world's longest triathlon, which has circumnavigated the entire coast of mainland Britain.

With the finish line in sight, he talks to Joanna Davis about the inspiring challenge and urges people to watch him complete the feat in Dorset.

YOU'LL recognise him swimming up to shore sporting a very distinctive shaggy beard complete with a wild, untamed mane of red hair.

Not only does Sean Conway look distinctive, his record-breaking achievement will make him distinctive.

I speak by phone to what I imagine to be a very bedraggled figure, who has just swum his way onto a West Sussex beach and is trying to dry off after his latest leg of the swimming part of his epic triathlon, which began in Brighton.

Sean is set to complete the world's longest triathlon early next week right here in Dorset.

People are invited to beauty spot Lulworth Cove to see the adventurer complete his cycle of more than 3,000 miles and run of 800 miles with a 100 mile swim.

Having cycled clockwise around England, Wales and then Scotland, Sean has overcome missed ferries, treacherous mountain roads and mechanical issues along the way. He spent his 35th birthday camping alone in a field on Cornwall’s border with Devon.

Following a cycle ride of more than 3,200 miles, Sean swapped his beloved bamboo bike, Matilda, for running shoes at Scarborough. An 800 mile run then took place, with Sean battling the terrain and his troublesome knee, averaging over a marathon each day in order to keep to his punishing schedule.

The 35-year-old has been frequently 'tweeting' whilst undertaking the extraordinary feat and will be updating supporters on his finish time, anticipated to be Monday or Tuesday.

The ridiculously impressive challenge has gained him a lot of fans on social media, thanks to his hashtag #GoSeanGo and is being filmed for a Discovery Channel documentary.

However, the experience is far from that of a glamorous TV star for Sean, as each night of the challenge he has been sleeping wherever he can find a makeshift bed from woodlands to an advertising trailer.

Sean calls me as he is taking a break from swimming westwards along the coast from Bognor Regis.

"At the moment I am just feeling cold from the water.

"I've got a raft that I like to call Rafty McRaftface, I've had to deal with it leaking.

"I've been dragging my belongings behind me.

"The tides are proving to be a bit of a problem - I've been getting up at 3.50am to get the first tide and I have to be very precise with that."

Sean, from Cheltenham, anticipates feeling a swell of relief when he finally reaches the finish line at Lulworth Cove.

"I know I'll also be feeling very tired.

"I'm bored of exercise at this stage. I now feel very tired, weak and skinny."

The decision to take on adventuring was an easy one for former school portrait photographer Sean.

He said: "I was miserable throughout my 20s doing a job I hated. You know that there's something wrong when children start crying right away when you go to take their photo.

"I sold my car for £1 in 2011 and decided to do my adventures. Rather than material items this was what was important to me.

"Five years later I'm still doing it."

On this challenge needing to take in the required 5,000 calories each day, Sean has foraged wild garlic leaves, tried dog treats due to their high protein content, and even liquidised roast dinners: “We found a pub on the route that was happy to blend up my Sunday roast, made up of peas, cabbage, mash, beef, Yorkshire pudding and gravy.

“You can absorb nutrients faster and waste less energy drinking food when it’s liquid. Who knew a roast dinner was three pints?”

Previously Sean had done similar challenges, but this is the biggest and the best - and the beard and hair have a lot to do with it, he says.

"I grew my beard on a swim in 2013 to scare off jellyfish, I think it gave me superpowers and now I'm practically superman.

"There is quite a lot of drag with it, but I'm used to that by now."

The swimming stage of the triathlon has also thrown up the odd surprise for Sean - he even managed to catch a mackerel while he was swimming by towing a line behind him.

Although Sean has no association with Dorset, the choice of Lulworth Cove was an easy one, he said.

"I chose it because I saw a picture of it and it looked cool. I thought it would be a nice place to think about as I was doing the triathlon.

"I find that you have to have a picture of somewhere in your mind, something to focus on.

"I just thought it was a really pretty place and I wanted to come up with somewhere that would be a nice place to start and finish."

Zimbabwean-born Sean said navigating himself along the English Channel hasn't been too difficult, but working around the timing of the tides has proved tricky.

He hopes that he can inspire the people who have supported him and the people who watch his adventures on the Discovery Channel.

"Part of the reason why I'm doing the documentary for the Discovery Chanel is because I'm working with them to get across the message about adventure and getting people outside.

"I want to encourage people to have a go and just go to a shop, buy a few items of kit and run out the front door."

People are invited to join Sean at the finish line at Lulworth Cove on Monday or Tuesday. There will be a Q&A and meet and greet session with Sean afterwards.

Follow Sean's progress to see when he will arrive at the finish at DiscoveryUK.com.

You can also track Sean's progress on Twitter at @Conway_Sean