A new study has suggested that running in reverse could make you fitter than running forward.
Despite its fashionable status, reverse running is not new. It emerged as an activity in its own right in the 1970s, when sports doctors began recommending it to injured athletes.
Physiotherapists approve of it because running backwards reduces impact on the joints. It's often recommended for rehabilitation from knee and back problems.
Overall, many experts say, it is a more efficient way of a fast-forward route to fitness, reports the Daily Mail.
The study at South Africa's Stellenbosch University showed that the technique improved cardiovascular fitness. Researchers looked at the effects of a six-week, thrice-weekly backward-running programme on female students compared with a group who stuck to their regular activity schedule.
At the end of the study, the reverse runners were found to have significant decreases in oxygen consumption, meaning they had become aerobically fitter, and had lost an average 2.5 per cent body fat.
James Bamber, organiser of the UK's backward races, says there are other subtle advantages. "Because you land and push off from the forefoot, your big toes are strengthened, which aids good posture."
"It improves co-ordination and has been proven to help cognitive functioning and reaction speed as a result."
Bamber says that running one lap of an athletics track backwards provides the fitness equivalent of running six laps forwards and that 100 steps in reverse produces the same benefits as 1,000 steps straight ahead.