A short walk to make a cup of tea could be the key to staying fit, research suggests. Sounds too good to be true? Well researchers have found regular short bursts of activity for as little as 10 to 30 seconds could burn more energy than previously thought. A laboratory trial of people on treadmills has provided the striking insight that when people break up a walk into shorter bursts they use up to 60% more energy. Scientists say that is because after the body has got going then walking becomes