A 91-year-old woman from Italy defied ageing norms as she sprinted through a 200-meter run in less than a minute, breaking the previous world record for her age group. The nonagenarian, Emma Maria Mazzenga, was comfortable even as her competitors were left grasping for breath. Here's what keeps her so fit and agile at this age.

200m in just 51 seconds
Emma last year finished a 200-meter dash in a matter of 51.47 seconds -- around 1.5 seconds faster than the previous world record for contestants aged over 90. After her record-shattering feat, a group of scientists put Emma through a series of tests to understand her physiology. They found out two main factors that make Emma fitter than many people younger than her.

Experts say that Emma's cardiorespiratory health -- which includes the efficiency with which her heart and lungs pump oxygen to her muscles -- is at par with a fit woman in her 40s or 50s.
Besides, her muscles are unique, great for endurance, which means she can run distances without feeling tired. Emma also has a "very high percentage" of fast-twitch fibres, which generate strong bursts of energy -- ideal for events like sprinting.

Emma's return to running
In an interview with Vogue Italy, Emma, who was born in 1933, said she started competing in running events while in college. In her young days, her top achievement was a fourth-place finish at the national championships in Rome. However, after getting married and having kids, she had to put her track career on pause for several decades. She returned to the sport in 1986 with her old teammates.
In her early 50s, she joined the masters athletics circuit -- competitive races for older runners -- and hasn't since looked back.
"All the costs are on me, but I’m happy to do it," Emma told the magazine. "The emotion that a race gives me, the adrenaline that each training session gives me, are the pure energy of my days."