How to Get a Great Cardio Workout in 20 Minutes

Think you're too busy to exercise? Think again: If you work out 3 or 4 days a week for only 20 minutes a day, you will still improve your cardiovascular health, burn calories and tone muscles. Read on for different ways to help you create an effective cardio workout in as little as 20 minutes a day. Remember, the harder you push yourself the greater the benefit, and the better you will feel when you’re done.

Instructions

Difficulty: Moderate

1. Ride a stationary bike. Pedal with a medium resistance and challenging cadence, increasing speed and resistance gradually. Don’t pedal like a maniac! Doing so might seem like the best way to get a good workout, but you will burn more calories if you maintain a cadence of 70 to 80 revolutions per minute (RPMs) with increased resistance.
2. Walk on a treadmill. Take rapid, long strides while pumping your elbows back and forth as you move, aiming for a pace of 4.5 miles per hour. You’ll burn more calories and get a better workout if you power walk instead of running at a very slow pace. Increase the incline on the treadmill 10 minutes into your workout, while maintaining your speed.
3. Run on a treadmill. Warm up for 3 minutes, increasing your pace from a jog to a comfortable run. Following the warm up, run 1 minute intervals: Start with a challenging pace for 1 minute, then recover at a slow run for 1 minute. Repeat. As you run lengthen your stride, lift your knees and pump your arms.
4. Use an elliptical trainer. Set the machine to a medium or high resistance and ramp position. Try to reach 70 to 85 percent of your target heart rate. It can be tricky to get a good workout on the elliptical trainer if you don’t know how the machine works. You’ll burn more calories with increased resistance. Remember that during a vigorous workout, your breathing should be labored.
5. Use a stair climber. Use the “Aerobic Workout” setting that is programmed into most machines. Increase resistance so that you are breathing hard, but never sacrifice form. Keep the body upright with hands lightly touching the machine, or for a greater challenge don’t touch the supports at all. Leaning heavily on the handlebars so you can go faster only decreases how hard the legs must work, cutting the calories expended.
6. Take a power walk outside. Walk as quickly as you can, maintaining proper form and control of your body, for the whole 20 minute workout. Choose a hilly course or one with a long (half-mile) medium incline. Try to complete a mile and a half in 20 minutes.
   
7. Do an interval run outside. Run at a hard pace for 100 meters, followed by a relaxed jog for 100 meters. Repeat this cycle for 20 minutes. Try to maintain your speed from the first interval to the last one.
8. Do a stationary biathlon. Run 1 mile on the treadmill at a hard pace. Then go directly to the bike and pedal at a challenging speed with a medium-to-hard resistance to complete your 20 minutes.
9. Get a cardio workout in the house on a rainy day. Run up and down your stairs 5 times. Next, do 2 sets of 25 crunches and 20 push-ups. Then stretch for 1 minute and repeat the whole cycle.

Tips & Warnings

• Stretch everyday--and always before a workout.
• Start slowly and gently, listening to your body. Don’t judge yourself.
• Hire a personal trainer if you have doubts about form, exertion level or need additional motivation.
• It's always a good idea to check with your doctor before beginning a new exercise routine.