IT'S that time of year again when hundreds of runners with a penchant for pain will descend on the nation's capital for the mother of all races.

Next Sunday, a total of 620 people from Hampshire will join more than 32,000 people for the 27th annual London Marathon.

Armed with water bottles, I-pods and more determination than you can shake a stick at, runners of all ages will pound the streets for what is arguably one of the toughest challenges in the world.

Jogger's nipple, toe nails that fall off and blisters that would put the fear of God into the average sportsman are just some of the pitfalls in undertaking this gruelling task.

At 26 miles and 385 yards long, (42.195km) the route takes runners past some of the capital's most famous landmarks including Canary Wharf, Tower Bridge, The London Eye, Buckingham Palace and Westminster.

Runners can expect a festival-like atmosphere along the entire length of the course as thousands of spectators and bands turn up to cheer them on.

One Southampton runner who will be joining them is William Dowdall, who at the age of 83 is Hampshire's oldest participant.

Great-grandfather William MBE, of Farrington Road, Thornhill, is planning to finish the event in just under 6.30 hours in what will be his ninth London Marathon.

He said: "My main influence for running is because I lost my wife Ana Marie to cancer 13 years ago so I'm hoping to raise £1,400 for the Wessex Cancer Trust. I feel like I'm doing something good in my life by running and raising money for people that are not aware that you are helping them.

"I started running when I was 73 because I had a minor stroke and my doctor referred me to Bitterne Leisure centre and it went from there really. A lot of people say I shouldn't be running it anymore but you have to make up your own mind about these things."

Another Southampton runner pounding the streets next week is fundraiser extraordinaire Aurelio Bello.

The big-hearted Spaniard has already run 22 marathons, including five London Marathons and raised more than £100,000 for charity over the past five years.

This year the 53-year-old is hoping to raise more than £7,500 for the national blind and deaf charity Sense and a new baby care unit at Southampton General Hospital.

Aurelio, a Vosper Thornycroft employee, is running for Sense because his granddaughter Tia, eight, is partially deaf.

He said: "I'd much rather run than be at home watching TV, it's too boring. The first few miles are always difficult, but once you get into the rhythm of running it can be very relaxing. It's either running or Coronation Street or EastEnders and I know which I prefer."

To sponsor Aurelio go to justgiving.com/aurelio.

But for many of next week's runners it will be their first experience of hitting the wall'. This is an uncomfortable experience that happens when your body runs out of its energy reserves and starts burning off fat instead.

Running expert Doctor Stuart Bruce-Low of Solent University, explains: "Hitting the wall is when you deplete your glycogen stores and use fats for energy. But this fuel source is not quickly available like your glycogen stores are, thus you feel as though you have no energy.

"The result is you feel disorientated, weak and you are unable to run at your usual pace (although this can happen anytime during the race some runners experience it around the 18-21 mile mark). To avoid this ensure you keep your glycogen levels topped up with energy drinks.

"The marathon is a long time running so maintaining focus for the full 26.4 miles is an arduous task.

"However, marathon runners state that the atmosphere and in particular the crowd really help to maintain a positive focus in those tired' moments."