A great article on high intensity interval training used to help teach your body how to burn more fat.  Intensity can mean vastly different things to many people so please take into consideration your own fitness level and capability.  If you’re not already, try changing up your current routine just a bit, add a few of these types of intervals to your weekly workout routine.  Your modality(treadmill, elliptical, rower, outdoor hill sprints, etc.) does not matter.  Choose a type of cardio that you are comfortable with, and push yourself just that much harder that usual.  You can do anything for 30 seconds – CHALLENGE YOURSELF!
Do sprints to get healthier and lose fat without losing muscle. A new study shows that an effective short-sprint workout can be done in half the time required for an endurance running program, and it produces better results.
Sports scientists compared the effects of a 7-week short-sprint training program and an endurance program on various health markers and running performance. Participants were all recreational runners with equal health status.
The sprint interval program took less than half the training time of the endurance running protocol, which consisted of three 8-km workouts a week. The sprint program included 3 to 5 sets of short sprints (10, 20, or 30 seconds in length).
Results showed that the short-sprint group increased maximal oxygen uptake by 5 percent, reduced systolic blood pressure by 5 mmHg, and lowered LDL cholesterol by a clinically significant amount. The endurance-training group had no improvements in any of these markers. In addition, the short-sprint group improved performance in a mile time trial by 6 percent whereas the endurance group had no change.
Researchers also measured markers of muscle adaptations to determine whether the workouts produced an environment that was anabolic so as to build muscle and improve body composition, or catabolic so as to degrade muscle.
The sprint triggered muscle protein synthesis, indicating that the high-intensity sprints can prevent loss of muscle tissue, which is particularly important if you want to get lean and keep the fat off. In contrast, the endurance group produced muscle protein breakdown, indicating that muscle and lean tissue is being lost as a result of the endurance training.
Sprints are your best bet if you want to be healthier, be leaner, and improve performance. They go well with a strength training program since both call on the anaerobic energy system to produce a better body composition.
Sprint training also produces adaptations that improve performance for activities that call on the aerobic energy systems, such as distance running, cycling, rowing, swimming, or soccer.
Bangsbo, J., Gunnarsson, T. The 10-20-30 Training Concept Improves Performance and Health Profile in Moderately Trained Runners. Journal of Applied Physiology. 2012. Published Ahead of Print.