Study highlights the physiological demands linked to breaking the fabled barrier

Elite marathon runners need a specific blend of physiological traits to stand a chance of breaking two hours in the marathon, according to a study from the University of Exeter published in the Journal of Applied Physiology.

Eliud Kipchoge was one of the athletes tested by Andy Jones, professor of applied physiology at Exeter and the study author, along with 16 others who took part in the selection stage of the ambitious Nike Breaking2 project of 2017. Kipchoge was to record 1:59:40.2 in the INEOS 1:59 challenge after the trial had finished.

READ MORE: Eliud Kipchoge runs sub-two-hour marathon

Jones reported that a “perfect balance” of a high VO2 max (maximal oxygen uptake) and high “lactate turn point” (the percentage of someone’s VO2 max that can be sustained before anaerobic respiration, and fatigue, set in) were also necessary attributes of potential sub-two-hour runners.

His findings showed that a 59kg runner would need to take in about four litres of oxygen per minute (or 67ml per kg of weight per minute) to maintain two-hour marathon pace (21.1km/hr) – meaning they take in oxygen during a marathon at double the speed a “normal” person of the same age would while sprinting flat out.

“Some of the results – particularly the VO2 max – were not actually as high as we expected,” Jones says. “But these runners possess a perfect balance of characteristics for marathon performance.”

Supreme efficiency of movement or an effective running action were also a requirement, to enable the body to use oxygen efficiently.

Of the athletes studied, 15 were from East Africa and, says Jones, “seemed to know intuitively how to run just below their ‘critical speed’, close to the ‘lactate turn point’ but never exceeding it.”

Across the board, they displayed “remarkable fatigue resistance”.

Jones says: “The requirements of a two-hour marathon have been extensively debated, but the actual physiological demands have never been reported before now.”