How to Get Fit in 8 Weeks

Create a workout schedule that includes cardio exercise four to five days per week and strength training two to three times per week. The American Heart Association recommends between 75 and 150 minute of cardio and resistance exercise per week, depending on the intensity of the workout.

Perform strength training and aerobic endurance workouts for the first four weeks of your program. Complete resistance exercises using an amount of weight or a resistance level that will fatigue you to failure if you continue performing the exercise for 90 seconds. Perform four to six repetitions of an exercise if you are using weights or resistance levels near your maximum, or eight to 12 reps if you are using a moderate resistance level. Complete three sets of each exercise, taking 60-second breaks between each set. Increase the amount of weight or resistance you use each week, even if it’s only by 2 or 3 pounds.

Exercise at the maximum heart rate you can sustain for 30 minutes if you are just getting back into shape. This might be as slow as a power walk, or 2.5 to 3.5 mph on a treadmill. Increase your speed each week, maintaining a pace you feel comfortable with for 30 minutes.

For example, if you walk 1.5 miles in 30 minutes during the first week, try to walk that distance in 25 minutes the next week, and add another five minutes to the workout. Alternately, increase the duration of your workouts, rather than increasing your speed, if you're not comfortable with raising your heart rate any higher.

Add intervals to your workouts in week three, working at a higher speed for 60 seconds every six to eight minutes. For example, during a power walk, jog for 60 seconds, then return to walking. During a stationary bike routine, decrease the resistance setting and pedal very fast for 60 seconds, then pedal slowly for two minutes before going back to your normal speed and resistance setting.

Reduce your strength training to once or twice a week after four weeks. Add resistance training on cardio days by performing the exercises with less weight and more repetitions to improve muscular endurance, or your ability to use your muscles for longer periods. Perform weighted exercises or calisthenics such as pushups, pullups, chinups and dips at roughly 50 percent of your maximum intensity for 15 minutes before you begin cardio workouts.

Add more intervals to your workouts beginning in week four. Add footwork and jumping exercises to improve your speed, agility and balance. Use plyo boxes to perform a variety of jumps that require you to use one foot, both feet, alternating steps and to move forward, backward, on an angle and laterally.

Create three-segment workouts beginning in week six. Start with 10 to 15 minutes of resistance exercise, then move to 20 to 30 minutes of steady-state cardio and finish with 10 minutes of high-intensity interval training.