"P90x" is a high-intensity program developed by BeachBody that combines yoga, strength training and kickboxing in to a series of sessions designed to help you burn through body fat and tone up. The California-based company, founded by Jon Congondon, is also responsible for other DVD-based fitness programs like "Insanity Workout" and "Brazilian Butt Lift." Each of the 13 P90xDVDs contains a five-minute warm-up and cool-down and a different workout. You alternate upper- and lower-body days throughout 12 weeks. Core exercises, stretching and cardio are also included.

The chest and back workout consists of multiple rounds of pushups, chin-ups and rowing exercises. Each exercise is timed in intervals of 30 seconds to two minutes and is simultaneously demonstrated using dumbbells, bands and chin-up bars. It starts with a five-minute warm-up of mostly low intensity stretching exercises and concludes with similar stretches. 

The explosive motion of this plyometrics workout is designed to recruit muscle fibers and burn through calories. It consists of a series of jumping exercises for sets of 30 seconds to two minutes and includes exercises such as squats, frog jumps and hopping on one foot. 

The shoulders and arms DVD is designed to give men the option to get big arms and women the option to target arm toning. You will use dumbbells, bands and body weights during each exercise for 30 to 90 seconds. 

The yoga DVD works to increase flexibility and reduce the risk of injury through lengthening and relaxing muscles. The workout favors an exercise named downward dog, which stretches your low back, butt, backs of your legs and calves. Yoga X is meant to be a recovery exercise session. 

The legs and back DVD focuses on squats, rows and a series of sit-to-stand exercises. You will need a chair, bands and dumb-bells for this workout. Expect to work as hard as you can for repeated sets of 30 to 90 seconds. That means you will have 30 to 90 seconds to do as many repetitions of the exercise as you can. Warm up and cool down with five minutes of slow stretching. This high-repetition set is ideal for burning fat, according to the National Academy of Sports Medicine. 

Kenpo X is cardio kickboxing. During this workout, you will be kicking, punching, shuffling and jumping. Each exercise is timed. and some will be combined to mix things up. It resembles a combination of martial arts and dancing. 

To round off your program, P90x includes a DVD devoted to stretching, with the goal to increase flexibility in every part of the body. This hour-long stretching session helps the body recover and prepares it to continue exercising at high intensities. 

Ab Ripper X is a 20-minute ab workout often used in conjunction with the other workouts. The exercises are creative variations on leg lifts, sit-ups and crunches performed over a varying number of repetitions.