FRIDAY, May 30, 2014 (HealthDay News) — A new study explains why an 18-year-old marathoner has a similar finishing time as a 60-year-old runner.

It’s because marathon runners have their best times when they are in their late 20s, with poorer performances when they’re younger and older, according to Spanish researchers who analyzed data from more than 45,000 runners who took part in the New York City Marathon in 2010 and 2011.

The best race times were achieved at age 27 for men and age 29 for women. Times were 4 percent slower for every year younger than these ages, and 2 percent slower for every year after those ages, according the findings in the journal Age.

“While the rate at which performance drops is moderate until the age of 55, from then on the drop becomes sharper in both male and female runners,” study author Juan Del Coso Garrigos, of Camilo Jose Cela University in Madrid, said in a Spanish Foundation for Science and Technology news release.

The researchers also found that gender differences in finishing times increase dramatically after a certain age.

“The difference in the amount of time it takes men and women to finish a marathon remains at approximately 20 percent until age 55. But from this age onwards the differences between the sexes are greater, and reach more than 40 percent at 70 years old,” Del Coso said.

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