P90X, or Power 90 Extreme, is a home exercise system developed by Tony Horton in conjunction with Beachbody and director Mason Bendewald, which claims to improve physical fitness in 90 days through a rigorous periodized training program combined with a nutrition and dietary supplement plan.

P90X is an intensive 90-day home fitness program that combines a variety of exercise styles, including strength training, cardio, yoga, plyometrics, and stretching. Most of the workouts are just under an hour in length, and feature Tony Horton as instructor and motivational leader along with 3 or 4 fellow exercisers as backup. For workouts that require weights, one of the backup exercisers will generally demonstrate the exercise using the alternative resistance bands. The backup exercisers also demonstrate some moves at lower levels of intensity for participants who aren't as fit. With the exception of the Ab Ripper X routine, each workout generally begins with about a 10 minutes dynamic warm-up and ends with a cool-down of 3–5 minutes.

The P90X program is 13 weeks in length, exercising six days per week. There are three rotations that come with the program: classic, lean, and doubles that all target different end goals. There are a total of 12 workouts that are included with the program, each targets the body in a different fashion.

1. Chest and Back

This superset chest-and-back-blasting workout emphasizes two classic upper-body exercises, push-ups and pull-ups, to build strength and develop shape. The combination of these two push and pull movements will help you burn loads of calories while simultaneously attacking, strengthening, and developing multiple muscle groups.

2. Plyometrics

Get ready to go airborne. With over 30 explosive jumping moves, you won't be spending much time on the ground during this highly intense cardio routine. Plyometrics, also known as jump training, has been proven to dramatically improve athletic performance. If your sport involves a ring, rink, field, court, or track, then this training will give you the edge. Just be prepared to "Bring It" for a full hour when you leap into this workout, because there is no letting up.

3. Shoulders and Arms

Nothing rounds out the perfect physique like a pair of well-defined arms and shoulders, and with its potent combination of pressing, curling, and fly movements, this routine will leave you feeling stronger and looking sexier. Whether you want to build muscle mass or just slim and tighten what you've already got, these targeted shoulder and arm exercises will get you the results you want.

4. Yoga X

Yoga is a vital part of any fitness regimen, and is an absolute must for an extreme program like P90X. This routine combines strength, balance, coordination, flexibility, and breath work to enhance your physique and calm your mind. Yoga X will leave you feeling energized, invigorated, and maybe even a little enlightened.

5. Legs and Back

Get ready to squat, lunge, and pull for a total-body workout like no other. While the main focus of this workout lies in strengthening and developing the leg muscles (quads, hamstrings, glutes, and calves), there's also a handful of great pull-up exercises to give your legs a quick breather while you work the upper body.

6. Kenpo X

Kenpo X was created to give P90X users a high-intensity cardiovascular workout packed with lots of punching and kicking combinations to improve balance, endurance, flexibility, and coordination. During this workout you'll learn some of the most effective ways to defend yourself, while at the same time getting your body in peak condition.

7. X Stretch

Stretching is the one thing that will help you achieve a higher level of athleticism over a longer period of time. The X Stretch routine is an integral part of the program that will help prevent injuries and avoid plateaus. The extensive full-body stretches that make up this routine use disciplines from Kenpo karate, hatha yoga, and various sports to ensure that your body is fully prepared to meet all P90X challenges head-on.

8. Core Synergistics

Each and every exercise in the Core Synergistics workout recruits multiple muscle groups to build and support the core (lumbar spine and trunk muscles), while at the same time conditioning your body from head to toe. Loaded with a variety of fun, unique, and challenging exercises, this routine will get you moving in all directions to maximize your P90X results.

9. Chest, Shoulders and Triceps

Packed with an array of moves that target both large and small muscles, this workout will do wonders for your upper body. In just one full sequence you'll get a healthy dose of presses, flys, and extensions to push you to the brink. The results will be a stronger, leaner, and highly defined upper torso that will leave you looking awesome, with or without a shirt.

10. Back & Biceps

With a host of curls and pull-ups, this routine will make it fun to flex those powerful biceps. But don't worry, ladies—by using lighter weight, you can focus on toning and tightening these showcase arm muscles without adding the size that most guys covet. Additionally, this workout will also provide some great back definition that everyone can appreciate. No matter what your goals, you will achieve them in dramatic fashion if you dig in and max out your reps.

11. Cardio X

This low-impact cardio routine can be used in a variety of ways to meet your P90X goals. Use it in addition to your standard P90X workload when you want to burn some extra calories, or as a substitute if your body needs a break from the program's high-impact workouts. Whatever your reason for using Cardio X, you'll find it to be a fun, full-throttle, fat burning workout that will leave you feeling lean and mean.

12. Ab Ripper X

The combination and sequence of movements in this unique workout taps into not only abdominal strength, but true core strength as well. Master these 11 highly effective exercises and you will achieve vital abdominal muscle strength to benefit your overall health and physical performance. You'll also develop that highly coveted 6-pack as you take Ab Ripper X to full throttle. It's extreme work that's better than any machine in any club.

P90X+

If you love P90X and you're saying, "Give me more," or, "I need a challenge" — then here it is, the P90X Plus Series. Tony amps up the Muscle Confusion with BRAND-NEW MOVES and never-before-seen workouts all set to hot music created exclusively for P90X Plus by Jason Scheff, lead singer of the band Chicago! The NEW P90X Plus will break through plateaus with intense new cardio, muscle chiseling, and ab/core-ripping moves to ramp up your results. Adding these new advanced workouts into your P90X rotation will literally TAKE YOUR WORKOUT TO THE NEXT LEVEL and create workout combinations beyond your imagination. Trust me, it doesn't get better than this .

1. Interval X Plus

A lot more effective than standard cardio, Interval X Plus propels your heart rate up and down with 3 speeds: recovery, medium, and full-out, creating the most dramatic change in the shortest period of time. (40 minutes)

2. Kenpo Cardio Plus

This advanced-level Kenpo, with new moves, will shred the most stubborn layer of fat with an all-out self-defense workout that builds stamina, balance, and agility. (40 minutes)

3. Total Body Plus

By adding new synergistic moves, your muscles get pumped, then recuperate in stages until you've got nothing left. An unprecedented total-body phenomenon. (45 minutes)

4. Upper Plus

This monster upper-body workout will defy the plateau phenomenon by blasting all the muscles from the hips on up: chest, back, biceps, triceps, and shoulders, in a complete synergistic P90X way. After this one, you won't be able to pick up a ping pong paddle for a couple hours. (45 minutes)

5. Abs/Core Plus

This advanced new ab/core workout adds 4 different positions (hanging, sitting, standing, and plank positions) to intensify your ab work and shred your midsection even faster. Is a ten-pack even possible? You'll find out. (20 minutes)