NAIROBI, Aug. 17 -- More Kenyan track athletes are switching from track to marathon as they grow older while opting for slower events.

The star runners who have announced their intent to scale to the energy-supping 42km race include Kenyans Vivian Cheruiyot formerly of the 5,000m and 10,000m fame, Ezekiel Kemboi (3,000m steeplechase) and Britain's Mo Farah (5,000m and 10,000m) among others.

They are following in the footsteps of earlier converts like Paul Tergat, Moses Tanui and Eliud Kipchoge of Kenya; Haile Gebrselassie and Kenenisa Bekele both of Ethiopia; and Shalane Flanagan of the United States - who have all won several elite marathon titles.

Geoffrey Kirui, who won the gold medal at the just-concluded World Athletics Championships in London, oscillates between the 10,000m and the marathon event.

"As athletes grow older, their legs give in speedwise especially when faced with younger and more agile runners. The old guards are therefore compelled to scale up to longer races which are slower but require more endurance," 1987 world marathon champion, Douglas Wakiihuri told Xinhua on Thursday.

Payout at elite city races is also one factor that compels track athletes to convert to marathon running where appearance fees, prize money and bonuses can jolt one's bank account upwards tremendously.

The prize money for winners of the Boston Marathon which stands at 150,000 U.S. dollars for example, is three times what a runner can make by winning Diamond League final on the track.

New York Marathon organizers dole out 100,000 dollars to the victors. Owing to the dynamism of the event, elite marathon runners do only a maximum of two races per year, with the rest of the time spent on training and recovering.

"The two-hour barrier in the marathon seems increasingly surmountable as more and more runners with tremendous pedigree are taking to road running and slowly nudging the marathon clock downwards," Nairobi-based sports scientist Bernard Migo, remarked.

World half marathon silver medalist, Bedan Karoki, and world cross country champion Geoffrey Kamworor both from Kenya are also heading to the road after their legs can no longer let them keep pace with the nimble upcoming runners that the east African nation churns out with regular consistency.

However, race-switching is not a new found novelty. Czech Emil Zatopek won the 5,000m, 10,000m and marathon races within eight days at the 1952 Olympics.

Frank Shorter from the United States won the marathon gold medal at the 1972 Olympic Games after running the 10,000m, whereas Finland's Lasse Viren won both long distance track events and finished fifth in the marathon at the 1976 Olympic Games.

NAIROBI, Aug. 17 -- More Kenyan track athletes are switching from track to marathon as they grow older while opting for slower events.

The star runners who have announced their intent to scale to the energy-supping 42km race include Kenyans Vivian Cheruiyot formerly of the 5,000m and 10,000m fame, Ezekiel Kemboi (3,000m steeplechase) and Britain's Mo Farah (5,000m and 10,000m) among others.

They are following in the footsteps of earlier converts like Paul Tergat, Moses Tanui and Eliud Kipchoge of Kenya; Haile Gebrselassie and Kenenisa Bekele both of Ethiopia; and Shalane Flanagan of the United States - who have all won several elite marathon titles.

Geoffrey Kirui, who won the gold medal at the just-concluded World Athletics Championships in London, oscillates between the 10,000m and the marathon event.

"As athletes grow older, their legs give in speedwise especially when faced with younger and more agile runners. The old guards are therefore compelled to scale up to longer races which are slower but require more endurance," 1987 world marathon champion, Douglas Wakiihuri told Xinhua on Thursday.

Payout at elite city races is also one factor that compels track athletes to convert to marathon running where appearance fees, prize money and bonuses can jolt one's bank account upwards tremendously.

The prize money for winners of the Boston Marathon which stands at 150,000 U.S. dollars for example, is three times what a runner can make by winning Diamond League final on the track.

New York Marathon organizers dole out 100,000 dollars to the victors. Owing to the dynamism of the event, elite marathon runners do only a maximum of two races per year, with the rest of the time spent on training and recovering.

"The two-hour barrier in the marathon seems increasingly surmountable as more and more runners with tremendous pedigree are taking to road running and slowly nudging the marathon clock downwards," Nairobi-based sports scientist Bernard Migo, remarked.

World half marathon silver medalist, Bedan Karoki, and world cross country champion Geoffrey Kamworor both from Kenya are also heading to the road after their legs can no longer let them keep pace with the nimble upcoming runners that the east African nation churns out with regular consistency.

However, race-switching is not a new found novelty. Czech Emil Zatopek won the 5,000m, 10,000m and marathon races within eight days at the 1952 Olympics.

Frank Shorter from the United States won the marathon gold medal at the 1972 Olympic Games after running the 10,000m, whereas Finland's Lasse Viren won both long distance track events and finished fifth in the marathon at the 1976 Olympic Games.