Burn 300 Calories in 30 minutes

If you're trying to burn calories and lose weight using cardio machines, I have a challenge for you: Put down the magazine, turn off the television and (gasp) stop looking at your watch. Okay, you can keep the walkman, but everything else has to go. Why the drastic measures? If you aren't paying attention, you may not be working as hard as you think.

Cardio Workouts at the Gym
The following workouts should give you some ideas on how to spice up your workouts and burn more calories by raising and lowering the intensity. Modify each workout according to your fitness level and feel free to increase or decrease speed, incline and/or workout time to fit your needs.

For each exercise, warm up with 5-10 minutes of light cardio and keep track of your Perceived Exertion or monitor your heart rate. Use this calorie calculator to determine how many calories you're burning. End with a cool down and stretch.

Treadmill
Start with incline at zero and speed at a comfortable pace (walking or jogging). Perceived Exertion (PE)=Level 5 (see Perceived Exertion Scale).

1 Minute: Raise incline one or more percent every 15 seconds. PE=5-6
1 Minute: Reduce the incline one percent every fifteen seconds. PE=6-7
3 Minutes: Walk or jog at a steady pace. PE=5

Repeat entire cycle for 30 or more minutes. Calories burned: 320 (based on 140 lb person)

Elliptical Trainer
Using manual program, enter workout time as 30 minutes and choose appropriate level

6 Minutes: Set ramps (if option) and resistance levels at medium level. PE=5
2 Minutes: Set ramps at highest level and increase resistance every 30 seconds. PE=6-8
2 Minutes: Lower ramps and resistance to comfortable level. PE=5
6 minutes: Set ramps and resistance to medium and go backwards. PE=5-6

Repeat entire cycle for remaining time. Calories Burned: 250-300 (based on 140 lb person)

Bike
Using the manual program, enter your workout time as 30 minutes and choose appropriate level
5 Minutes: Cycle at a comfortable pace. PE=5.
5 Minutes: Raise level several increments and decrease a level every 30 seconds. PE=6-8.
5 Minutes: Cycle at comfortable pace. PE=5.
5 Minutes: Raise level higher than before and decrease a level every 30 seconds. PE=6-8
5 Minutes: Cycle at comfortable pace. PE=5.
5 Minutes: At current level, increase a level each minute. PE=7-8.

Calories Burned: 245 (based on 140 lb person)

Hit the Road
Instead of spending 40 minutes inside a sweaty gym, head outside for a walk/run.

Warm up with a brisk walk/slow jog for 5-10 minutes.
Jog/walk briskly for 3 minutes
Sprint or speed walk for 30 seconds
Repeat this cycle 6 for the remaining time, keeping PE between 5-8.

As you can see, it's easy to spice up your workouts by playing around with your speed, incline and resistance and alternating high intensity intervals with recovery periods. This not only keeps you from getting bored, it also helps burn more calories and increases your endurance very quickly.

Use this technique with any cardio activity to keep things interesting!