28 September 2014 Last updated at 10:33 GMT

Dennis Kimetto breaks world marathon record in Berlin

Kenya's Dennis Kimetto has broken the marathon world record in Berlin, winning the race in a time of two hours, two minutes and 57 seconds.

The 30-year-old shook off fellow Kenyan Emmanuel Mutai with just under three miles remaining to become the first man to run a marathon in less than two hours and three minutes.
Mutai, who finished second in 2:03:13, also broke the previous record.
"I feel good because I won a very tough race," said Kimetto.
"I felt good from the start and in the last few miles I felt I could do it and break the record."

Men's marathon world record decade-by-decade
Year	Time	Athlete	Course
1947	2:25.39	Suh Yun-bok (Korea)	Boston
1958	2:15.17	Sergei Popov (Soviet Union)	Stockholm
1969	2:08.33	Derek Clayton (Australia)	Antwerp
1988	2:06.50	Belayneh Dinsamo (Ethiopia)	Rotterdam
1999	2:05.42	Khalid Khannouchi (Morocco)	Chicago
2008	2:03.59	Haile Gebrselassie (Ethiopia)	Berlin
2014	2:02.57	Dennis Kimetto (Kenya)	Berlin

The previous world record had been set on the same course 12 months ago by Kimetto's compatriot Wilson Kipsang, who ran 2:03:23.
Kimetto, who won marathons in Tokyo and Chicago last year, had promised to attack the record in Berlin if conditions allowed.
And in weather perfect for long-distance running, with temperatures around eight degrees centigrade, Kimetto kept his promise, staying in the lead group throughout and sprinting to victory and a new world's best time.
Mutai, meanwhile, believes a two-hour marathon is possible.
"From what I saw today, times are coming down and down. So if not today, then tomorrow," the 29-year-old Kenyan said. "Maybe next time we'll get 2:01."
Scott Overall was the top British athlete in the men's race, finishing 14th in 2:13:00.
Britain's Shelly Woods won the women's wheelchair race as she continues her preparation for November's New York Marathon.