Skip to main content

A Review of P90X: Shoulders and Arms

I worked at a gym through college and have been a fitness junkie ever since, trying everything from P90X to yoga to power lifting.

A review of the shoulders and arms part of P90X: Plyometrics

A review of the shoulders and arms part of P90X: Plyometrics

P90X: Shoulders and Arms

This is the third in a series of reviews of the individual workouts within the P90X program. For all other reviews of the workouts, as well as a review of the overall program, please see the links at the bottom of the page.

I am a long-time fitness enthusiast who’s completed P90X twice. While I haven’t found the program to be the transformative experience it’s purported to be, I find it to be overall beneficial and very effective at keeping me on track fitness-wise when I don’t have reliable access to a gym.

Before I started on P90X the first time, I noticed that there was a dearth of workout-by-workout reviews, leaving me with little idea of what to expect from the program. I aim to correct that, and to give you an experienced exerciser’s perspective on the benefits and disadvantages of P90X.

Today we’ll be focusing on the third workout in line, and possibly the silliest: P90X: Shoulders and Arms.

The deltoids, or shoulder muscles: one of the muscle groups you'll be (over)working during P90X: Shoulders and Arms.

The deltoids, or shoulder muscles: one of the muscle groups you'll be (over)working during P90X: Shoulders and Arms.

Confession time:

I hate this workout. I really, truly do.

It’s not that it’s difficult. If you’ve lifted weights at all in recent memory, you’ll get through it just fine. Even if you haven’t, your arms may be sore for a couple of days, but it won't beat the soreness you'll get from P90X: Plyometrics or even P90X: Chest and Back.

No, the reason I hate this workout is that it's a little pointless.

Let me explain why.

The biceps: the muscle group which contracts when you bend your arm.  It's also the opposing muscle group to your triceps, and one of the muscles (over)exercised in P90X: Shoulders and Arms.

The biceps: the muscle group which contracts when you bend your arm. It's also the opposing muscle group to your triceps, and one of the muscles (over)exercised in P90X: Shoulders and Arms.

Compound vs. Isolation Exercises

I went into this subject briefly in my overall P90X review, but to sum up, there are two basic categories of weight training exercises: isolation exercises and compound exercises.

Compound Excercises

Compound exercises are so-called because they involve multiple joints and therefore multiple muscle groups. A bench press, since it requires both your shoulder joints and your elbow joints to move, is a compound exercise. A squat, since it involves movement at the hips, knees, and ankles, is also a compound exercise.

Compound exercises are excellent, because they require several muscle groups to work in synergy. During a bench press, you’re not only using your pectoral muscles, but you’re also using your deltoids and triceps to help push the weight up and away from you.

Why Work Multiple Muscle Groups at the Same Time?

There are three reasons:

Scroll to Continue
  1. Training multiple muscle groups at once, makes your workout more efficient, potentially reducing the amount of time you need to spend at the gym or freeing up more time to spend on cardiovascular and flexibility training.
  2. It raises your heart rate more and burns more calories overall since all of those big muscle groups need lots of energy to do their work.
  3. It builds what's called "functional strength" by mimicking real-life movements. In real life, you seldom use just one muscle group at a time. So why would you train them to work one at a time?

In real life, lifting a bag of mulch requires your legs, back, and even arms to be not only strong, but capable of working together in harmony. It's mimicked by squats and deadlifts, which means that doing those will improve your ability to hoist that mulch. Have to move some furniture? Bench presses train your ability to push heavy weights around with your chest and arms, and squats and deadlifts help you push through your legs and back, too. Pull-ups will strengthen your back and arms like nothing else, thus helping with all of those things.

Isolation Exercises

If you can perform lots of bicep curls, on the other hand, what you're doing is training your ability to do lots of bicep curls. There are few instances where this actually helps you do anything in the real world. Possibly this may come in handy the next time you decide to make a lemon meringue pie and find out that your mixer broke, leaving you to whip all of those egg whites by hand - but otherwise, it's probably more useful to be able to pick up a box of cat litter without throwing your back out. And for that, you need compound exercises.

Worse yet, minor muscle groups tend to be more delicate, and over-focusing on them is one of the biggest causes of repetitive strain injuries in strength training. Bear in mind that when you're doing a bench press, your triceps are working, and they're working hard. Force them to do eighty bazillion pushdowns on top of it, and you might run into trouble.

You might say: But I don't feel like I've had a real workout unless I've done curls and kickbacks, too.

And I'd respond: No one's saying you can't do them if you want to. Just don't make them the main focus of your workout. You won't get nearly the same results.

My Own Experience

After several years of succumbing to the trend of Bosu balls and "sculpting," I finally moved to doing heavy, compound lifts.

Not only did I lose the last few stubborn pounds of belly fat and make significant strength gains overall, but after three months of doing lots of chin-ups but no bicep curls, I finally tried a bicep curl and found myself lifting about ten pounds more than my previous maximum. Given that my previous maximum was fifteen pounds, that was quite a jump.

You heard that right: I got better at biceps curls by not doing bicep curls.

Compound exercises just work.

That's why I so intensely dislike P90X: Shoulders and Arms. It should be renamed to P90X: Why Am I Doing This, Again?

No matter how much I disagree, though, if I'm doing (and reviewing) P90X, I figure that I might as well do all of it - the good and the bad.

And so, dutifully, I've been slogging through Shoulders and Arms, week-by-week, like a good P90X-er.

Just don't expect me not to complain about it.

The triceps: the muscle group which, on contraction, allows you to extend your arms.  Often works in concert with the pectorals, and will get worked out not-quite-as-hard as the biceps during Shoulders and Arms.

The triceps: the muscle group which, on contraction, allows you to extend your arms. Often works in concert with the pectorals, and will get worked out not-quite-as-hard as the biceps during Shoulders and Arms.

The Workout Itself

All of that being said, P90X: Shoulders and Arms is not entirely made up of isolation work. Some of the moves involve more than one muscle group, and that's grand.

The workout consists of fifteen deltoid, bicep, and tricep exercises, each one repeated twice for a total of thirty sets. The first twelve are an obligatory part of the workout. The last three are considered optional, bringing you down to twenty-four sets overall if you decide your shoulders and arms have had enough.

The exercises in P90X: Shoulders and Arms are arranged in series of three: a shoulder exercise followed by a bicep exercise followed by a tricep exercise. As mentioned above, each exercise is repeated twice.

This sort of follows the principle of supersets. Supersets are sets of alternating exercises which work opposing muscle groups back-to-back, with little to no rest in between sets. Typically, you take a rest in between sets of similar exercises, because otherwise, you'll exhaust the targeted muscle group too much, too soon. With opposing muscle groups, this isn't nearly as much of a problem, since one muscle group is able to rest while the other is working. Most often this is applied to exercises that target the chest and back, but it can also be applied to the biceps and triceps, or hamstrings and quadriceps.

Where Shoulders and Arms falls down a little is where it tries to do supersets and doesn't quite succeed. Like it or not, most bicep or tricep exercises involve the shoulders in some way. Following a set of shoulder exercises with curls and kickbacks won't really give the shoulders a rest. Neither will doing a set of chair dips so soon after you've done shoulder presses, since chair dips heavily involve the shoulders (the anterior deltoids, specifically) as well as the triceps.

In the case of the Deep Swimmer's Press, the second shoulder exercise in the series, the biceps are even brought heavily into play, since the move essentially consists of a bicep curl followed by a shoulder press. This might be fine if you weren't doing a set of concentration curls immediately afterward. Since you are, however, you might easily end up doing about thirty curls in a row.

To put that in perspective, eight reps is the point after which you begin experiencing diminishing returns, and even personal trainers who espouse high-rep, low-weight training caution against going above fifteen. Thirty in a row is arguably overkill.

In addition, a rule of thumb is to do no more than five sets for any one muscle group in the same workout. If you skip the bonus round, you'll be doing eight sets for each muscle group, not counting the exercises which blur the lines, like the Deep Swimmer's Press. See what I mean about overkill?

On the positive side, however, the workout does include some compound moves, such as shoulder presses and chair dips. It also leaves room to cut out after the twelfth exercise. Frankly, I would do so. Move on to Ab Ripper and call today a light day, or throw in a session of Cardio X if you feel you still haven't gotten enough of a workout. Overworking minor muscle groups can be very unwise.

Another view of the triceps and biceps and how they work together.

Another view of the triceps and biceps and how they work together.

Getting the most out of P90X: Shoulders and Arms

Here are some of my personal tips to help you get the most out of this workout.

1. Stand Tall

Most of the exercises in this workout are standing exercises.

This means that, in order to protect your low back and stabilize your posture so that you have a good foundation for each move (no wobbling!), you'll need to think a little about how, exactly, you're standing.

Tony Horton and his compadres will all be standing with one foot forward and both knees slightly bent. I don't like this, because I have low back problems and I find that this posture throws my back off balance and into too deep an arch.

As an alternative to what Tony presents, try standing with your feet hip-width apart, bearing a few things in mind as you do so:

First of all, as always, think of your core. You don't want to suck in your abs until they feel like they've been pinned to your spine. You do want to keep them lightly tensed, however, just until you start to feel more stable.

Second of all, to build a better foundation and protect your lower back, bend your knees slightly. This doesn't mean crouch. What it means is to avoid locking your knees and to keep just enough of a bend in them that you can feel your pelvis tilt back slightly, your abs tighten, and your lower back flattens out. Not only does this help you engage your core more and keep to a tighter, more stable position, but in keeping your low back from arching too much under load, you're protecting it from strain and injury. I have low back problems, myself, and I find that this simple postural adjustment makes all the difference in the world.

Again: these adjustments are slight and subtle. You should feel them, but don't exaggerate them. I don't want you standing there with a thirty-degree bend in your knees, an Elvis pelvis, and your abs so tight you can't breathe.

2. Mind Your Elbows

Everybody's first instinct, when struggling with a difficult bicep curl, is to move their elbow forward in order to help the weight up. This automatically reduces the load on your biceps and allows you to get the weight up more easily. Similarly, most people will find themselves tempted to cheat by leaning back, which also reduces the load on the bicep and makes it easier to get the weight up.

I don't want you to do that. I want you to keep the load on your biceps, since that's what we're supposed to be working out, here. Keep your elbows back and down and your posture stable. If you can't do eight reps without cheating, switch to a lower weight.

Similarly, don't let your elbows sag down during tricep kickbacks. This is a normal response since lower elbows mean you don't have to push back as far, which means the exercise will be easier. However, this also means it's less effective, not to mention more likely to hurt you, since your elbows are now going off at unpredictable angles. If your elbows are going all over the place during the tricep exercises, swallow your pride and switch to a lower weight.

Oh, and whether you have one foot forward or both hip-width apart, do keep a flat back when you're doing those kickbacks. Your spine will thank you.

3. Have Lots of Weights

Shoulders and Arms will have you switching through a variety of more or less isolating exercises for three different muscle groups. This means that the amount of weight you're going to need will vary widely.

For women who are beginners to strength training, I'd recommend starting at a set of five, eight, and ten-pound dumbbells, with room in your budget to eventually get a set of twelves and even fifteens. For women who have some strength training background, start at eight, ten, and twelve, considering it highly likely that you'll need a set of fifteens as well. Keep a set of twenties or twenty-fives open as an option, but don't get them immediately unless you're naturally a pretty strong gal.

For men, start out with tens, fifteens, twenties, and twenty-fives, then add weight as needed.

4. Have A Sense of Humor

You always need this with Tony Horton. You can't really take him seriously. If you do, you might end up putting a dumbbell through the TV.


For an overall review of the P90X program as well as workout-specific reviews, see:

- P90X: Chest and Back

- P90X: Plyometrics

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.


Ouch on May 23, 2019:


Tom Schumacher from Huntington Beach, CA on April 16, 2013:

Both isolation and compound exercise movements have their purpose. For dumbbell weights, I suggest Bowflex 552 or 1090. I purchased the 1090 set a couple of months ago and they're amazing; quick easy selector, solid construction, and lots of weight ranges to choose from. And, the stand is an essential component to make the transitions more convenient and safer. See

Amanda Zahorik (author) from Philadelphia, PA on April 16, 2013:

I agree that isolation exercises are helpful as accessory exercises. What I don't agree on is that it's a good idea to build an entire workout on so many sets of them. I think this workout goes well past the point of diminishing returns. I'd rather see two upper body workouts in one week with both compound and accessory exercises included.

Nik on March 27, 2013:

I disagree with you about the point of this workout. It is true that doing compound exercises is usually better than isolation, however, isolating certain muscles does help in doing more compound exercises. Take the pullups for example. If your back is strong, but you lack strength in your biceps, then the shoulders and arms workout will help balance this out. The same thing applies in the pushup where the chest, the shoulders, and the triceps are engaged. Strengthening your shoulders and triceps will help you do more pushups.

Related Articles