10 Minute Total Body WorkoutJust about everyone acknowledges the importance of exercise for better health. However, finding time to devote to the gym doesn't always fit into your busy schedule. Health expert Sean Foy, author of "The Ten-Minute Total Body Breakthrough," believes that a lengthier workout isn't always the best workout, and he cites research to back up his assertions.Variable activity, he says, can burn up to nine times more fat than a similar amount of steady-state activity. That means you can get an effective full-body workout in a fraction of the time you would spend doing a single repetitive exercise. The key is to use the philosophy behind circuit training -- intervals of medium-intensity effort punctuated with episodes of all-out action and static resistance -- to compress a full workout into a shorter time frame.The 10-Minute Workout: Doing More in Less TimeSean Foy devised the 4-3-2-1 workout as a means to fit a full exercise regimen into a busy schedule. The 4-3-2-1 system gets its name from the number of minutes spent in each phase of the program. All the elements of a full workout -- cardiovascular exercise, resistance training, core strength and cool-down stretches -- are present in the 4-3-2-1 system, but in a condensed form that focuses on multiple major muscle groups at once for a more efficient training session.Devote four minutes to cardiovascular exercise, three minutes to resistance, two minutes to core strength and the final minute to flexibility every other day, Foy recommends. The author demonstrated moves for each step of the workout plan, but you can vary your moves to keep the workout interesting as long as you adhere to the format.The 4-3-2-1 Workout Step by StepStart with four minutes of high-intensity aerobics training, or HEAT. Alternate 30 seconds of an aerobic exercise at moderate intensity with 30 seconds of all-out effort for a total of eight intervals during your workout's initial phase. Foy demonstrated with a "chair jog," pumping arms and legs while remaining seated. A treadmill or exercise cycle could also provide an aerobic workout.Three minutes of resistance training helps you build greater muscle strength and sturdier bones. Foy demonstrated with a static lunge, a move that works all the major muscle groups of the lower body and back, that he recommended holding for 30 seconds per leg. Push-ups and weights work the upper body, so give some attention to both your upper and lower body during the resistance phase.Spend two minutes developing your core strength with moves like chair planks and pointer poses. These yoga-influenced positions give your abdominal and back muscles a workout without requiring dozens of crunches.A final minute of deep breathing and stretching enhances your flexibility, bringing your 4-3-2-1 workout to a close.Although it's short, this workout is intense, so Foy recommends doing it on alternating days. On days without a 4-3-2-1 workout, he suggests making time for ten minutes of other forms of exercise.