high-intensity interval training

In summary, the researchers concluded that the shorter exercise session appears to have allowed the men to "burn calories without wanting to replace them." Combined with greater activity levels at work and off-hours, the overall health effect generated was greater than in those whose workout sessions were longer, simply because the latter didn't experience the same boost in off-hour energy levels, and ended up eating more.
http://fitness.mercola.com/sites/fitness/archive/2012/10/12/goldilocks-exercise-zone.aspx?e_cid=20121012_DNL_art_1