Do HIIT(High Intensity Interval Training) for fat removal and muscle gains. Very quickly done compared to jogging for an hour.
It's hellishly hard though, but supposed to be better than jogging for fat removal and keeping muscle, even though you just use like 1/4 the time.
Quick summary of HIIT Training:
http://www.musclemedia.com/training/hiit.asp
Forum about Fat loss(and HIIT training):
Losing fat forum on Bodybuilding.com