The Insanity Workout program is designed to give you the ideal plyometric workout without the need for additional equipment or added weights. Developed by Shaun T. based on his track and field experience, this is a regimen that claims you can achieve better fitness within 60 days with intense stamina training.

I have run through Shaun T.s program four times now. It truly will wipe you out. It is the like the P90X or 300 equivalent, but with cardio only. Don't get me wrong, there is a bunch of body weight driven exercises.

Every time I have done Shaun T's program, I have injured myself. It has to be all the pounding and bounding you do. It's always my ankle or knee. I break out the tape and braces for the next workout. The first time I ever did Insanity, when they were done with the warm up, I was already to throw up, and it's that tough. It is definitely the closest cardio workout to Navy Seals training. You really need to schedule this thing into your life.

With the Insanity workout, one goes through a strenuous routine for 3 to 4 minutes, then cools down for 30 seconds, then starts over. A complete opposite to interval training, which you do a rigorous exercise for 30 seconds and then cool down for at least 3 minutes. But each time you re-do an interval, you are asked to do it harder than the last. So it looks like this:

Interval 1 - Do it at a level that you breathe well with.

Interval 2 - You should barely be able to breathe.

Interval 3 - 101%, who needs to breathe?

What the Insanity Workout does is that it lets you beat the feeling of your body getting used to the level of exercise where it normally stops improving. It replaces an average workout with a maximum-intensity routine, where your heart rate is raised over its maximum capacity, and forces your body to use muscles that are not normally used in cardio workouts. This way, your muscles continue to burn even when doing low-intensity workouts. Eventually, you'll see faster results and more efficient calorie-burning capacity to as much as 1,000 calories per hour.

This program is one of the most difficult DVD workout programs out there and is probably at the top of the list. The workout schedule is changed weekly. During the first month, you will be alternating 5 workouts: the Fit Test, the Plyometric Cardio Circuit, Cardio Power and Resistance, Cardio Recovery and Pure Cardio. Before the first month ends, there will be a recovery week that involves a daily core cardio and balance, not as intense as the other routines but helps you prepare for more intensive second month.

On the following month, you are introduced to four other workouts: the Max Interval Circuit, the Max Interval Plyo, the Max Cardio Conditioning, and the Max Recovery. These routines are very hard to keep up with. You'll have to work longer and with more intensity than what you did with the first month.

Typically, Insanity starts out with warm-ups that consist of jogging in place, kicks, stretching, jumping jacks and side-to-side jumps. You will most likely have problems keeping up with the warm-up when you start out. Other exercises include sprinting in place, squats, kickboxing movements, lunges, and push-ups. The pace is what makes the workout extremely intense apart from the number of reps.

If you are a fitness buff, you will definitely enjoy the intensity and the challenge of finishing the program in 60 days. As mentioned earlier, there is no need for any additional equipment. The variety of DVDs included with the Insanity program also keeps your workout from becoming a boring chore. There's also a workout calendar and the Elite Nutrition plan to support your workout regimen.

With the intensity of the Insanity program, it is not targeted towards unfit individuals. The program is designed to cater to people who are fit and are looking to improve their fitness. As this is a home based program, you will need a great deal of discipline to complete the 60-day plan. It is also not for individuals wanting to increase muscle mass. Smaller amounts of resistance using your own weight like push-ups and squats are as close you can get to weights here.

As the name implies, the Insanity Workout by Shaun T. tests your limits physically and mentally. If you are out of shape, have serious illness, this is not the regimen for you. If you are an athlete or a gym buff, and looking to improve the way you look with less time, this is definitely a must have for you.