High-altitude training has been found to be more effective for boosting weight-loss, increasing energy consumption and burning fat than training at sea level.

"Even walking in highlands where you don't have to worry about altitude sickness is good for losing weight," said Tamotsu Terao, a professor at the Sports Medical Science Institute of Tokai University in Hiratsuka, Kanagawa Prefecture.

Marathon runners and swimmers have long trained at high altitudes to strengthen their heart and lung functions.

The body must work harder to obtain the same amount of oxygen it gets more easily at lower altitudes, and over time it adapts, functioning more efficiently, and the athletes' stamina increases.

University researchers are simulating high-altitude environments to develop programs for the general public to prevent and treat lifestyle-related diseases, such as high blood pressure and diabetes, which are exacerbated by obesity.

The institute has built a low-pressure, low-oxygen room that can create conditions similar to those at altitudes of up to 4 km -- higher than Mount Fuji.

The researchers fixed the environment in the room to match conditions 1.5 km above sea level and asked six overweight men aged between 25 and 60 to walk for one hour to measure their energy consumption.

Under sea-level conditions, the amount of energy consumed one hour after such exercise was about 33 kilocalories per kg of weight per day. The average amount consumed under high-altitude conditions was about 39 kilocalories.

The estimated energy consumption from fat was 21 kilocalories at sea level and 27 kilocalories at a higher altitude.

Fifteen hours after the exercise, the estimated energy consumption under high-altitude conditions was found to be larger than that under sea-level conditions.

Terao and other researchers have concluded that walkers begin burning fat earlier at higher altitudes than at sea level.