After his visit to DARPA, the former infantry officer told the Sunday Express: ‘It’s all about improving the efficiency of energy creation in the body.

‘Soldiers would be able to run at Olympic speeds, carry large weights and go without sleep and without food.’

Washington’s military scientists are also hoping to work out how to trigger cells to regrow limbs for soldiers maimed by enemy bombs and landmines.

With well-documented cases already of young children regrowing fingers severed in accidents, DARPA is throwing significant sums at research to identify the physiological trigger and activate it in adults.