Longest marathon in the world

When the starting pistol fires on ultramarathons, the finishing line can be days or even weeks away, pushing competitors' minds and bodies to their absolute limit.

Tom Dickinson, associate lecturer in Sports Conditioning at Solent University, England, has helped train athletes for Morocco's Marathon De Sables (a six-day, 251 km ultramarathon).

He told Newsweek that physical and mental robustness, nutrition, equipment, climate, topography and physiological fitness "all contribute to a successful ultra."

"Failure to align these elements not only increases the chance of a DNF but also potentially renders the athletes at risk of significant injury.

"To use a baking analogy - the cake, like the ultra, is only ever baked once; it is the quality of the ingredients that determines the success of the taste. Far better to spend time improving specific elements (metabolic data points, practicing with specialist equipment, and conducting environmental preparation) than merely increasing t