Ep. #384: Are Compound Exercises Better Than Isolation Exercises?

Mike: [00:00:28] Hey, Mike Matthews here from Muscle For Life and Legion Athletics, and welcome to another Muscle For Life podcast. This one is going to be about compound exercises, compound exercises versus isolation exercises, which are better for what and why.

[00:00:44] So if you’re listening to this, you probably would like to build some muscle, you probably would like to get a bit stronger and you probably would like to do those things as quickly and effectively as possible. And that being the case, the exercise choices that you make matter. Some exercises are going to serve you better than others.

Which exercises? Well, some people will say that compound exercises are all you need, period. These exercises train every major muscle group in your body and are highly functional. And that’s it. That’s all you really need to do, is get strong on a handful of key exercises and you will have the body of your dreams. Full stop.

[00:01:25] Other people say that these exercises are overrated or even dangerous and that the right isolation exercises can give you everything your little heart desires with none of the risks of injury or pain.

[00:01:41] Who is right? Well, in this podcast, you are going to find out by the end. You are going to understand the pros and cons of both compound and isolation exercises, as well as how you should use them in your workouts based on your goals.

[00:04:07] All righty, so as we always do, let’s start this discussion at the top with a definition of terms. What is a compound exercise?

[00:04:15] Well, a compound exercise is one that involves multiple joints and multiple major muscle groups. For example, the squat, the barbell squat is the granddaddy of all compound exercises, and it involves moving the knees, ankles, and hip joint. And it requires a whole-body coordinated effort, really, with the quads, hamstrings, and glutes bearing the brunt of the load. 

[00:04:42] On the other hand, an exercise like the Russian leg curl involves moving the knees and focuses really on strengthening the hamstrings and glutes. And of course, there are other muscles that that exercise engages, but not forcefully enough to really stimulate muscle growth. And that’s why the Russian leg curl is not considered a compound exercise. It is an isolation exercise, which we will talk more about in a minute.

[00:05:11] So let’s talk common compound exercises that you’ll find in many popular weightlifting and especially strength training programs. You have the bench press. So all variations of the bench press, barbell, and dumbbell, flat and incline and decline are all compound exercises. The primary major muscle group trained here is the chest, the pictorials, but all bench pressing also heavily involves the shoulders and the triceps as well.

[00:05:40] You have the overhead press. This is also known as the military press and you can do it both seated and standing. And it is one of the best shoulder exercises you can do. It also trains the triceps. And when it is performed standing, the back, and the core are involved to a fair degree as well.

[00:06:01] Another compound exercise that I often recommend is the dip because it is a fantastic upper body compound exercise that can be performed in a couple of ways. You can do it upright and you can also do with a slight forward lean.

So when you are upright, really just straight up and down the primary major muscle group engaged is the triceps, but the shoulders and the chest are also primary assisters. And when you are leaning slightly forward, the chest becomes the primary mover. That’s the primary major muscle group. And then the triceps in the shoulders assist.

[00:06:35] You have the deadlift, of course, all variations of deadlifts: sumo deadlifts, trap bar deadlifts, conventional deadlifts, even dumbbell deadlifts. The deadlift, just that basic movement really is, I think, the single most effective compound exercises you can do because it involves just about every joint and every major muscle group in your body.

The primary major muscle groups trained, however, are known as the posterior chain and these are the muscles on the backside of your body, such as your hamstrings, glutes, and your back muscles. Pretty much every other muscle group in your body assists in the deadlift.

[00:07:12] You have the pull-up. The pull up is a simple compound exercise that will never go out of style because it works. The primary major muscle group involved here is the back and the secondary muscle groups are the biceps and the forearms.

[00:07:26] You have the cable pull-down. So this is essentially a machine pull up that allows you to specify the amount of weight that you want to pull. And accordingly, the primary major muscle group involved here is the back and the secondaries are the biceps and the forearms. 

[00:07:41] Rows, whether barbell, dumbbell, or even machine are compound exercises. So the primary major muscle group involved in a row is the back and the secondaries are the biceps and the forearms.

[00:07:54] You have the squat, of course. And like the deadlift, it is not just another compound exercise. It’s really a whole-body exercise. And that goes for all variations of the squat. You have the front squat, you have the back squat, you have the split squat, and so forth. It’s estimated that over 200 muscles are activated in the squat.

But the primary major muscle group trained is the quadriceps. It is primarily a quadriceps exercise even performed correctly, which means getting down to depth, at least that’s one of the key points of squatting correctly. And the deeper you squat, the more your hamstrings become involved, but it still is primarily a quadriceps exercise.

So when performed properly, you have the quads doing most of the work. Then you also have the glutes, hamstrings, and calves being forcefully recruited as well.

[00:08:41] Another great compound exercise is the leg press. This is one that requires less technical skill and fewer stabilizing muscles than the squat. But similar to the squat, it involves a lot of lower body muscles. The primary major muscle group trained by the leg press is the quadriceps and the secondary groups are the hamstrings and the glutes. Again, very similar to the squat in terms of how it trains your lower body.

[00:09:08] So the bottom line here is, as you have heard, most simple movements that have you push, pull, and squat against the forces of gravity are compound exercises. Now, you may have also noticed that all pushing involves the chest, shoulders, and triceps. All pulling involves the back and biceps. And squatting and deadlifting involve large portions of the body.

And also, if you have some weightlifting experience on your belt, you also know that compound exercises also allow you to safely use heavyweights, which is important for increasing your whole-body strength, which should be your number one goal as a natural weightlifter. And that’s why compound exercises are particularly good for gaining muscle and strength. And we will talk a bit more about this soon.

[00:10:02] Before we do, let’s now talk about isolation exercises. What is an isolation exercise? Well, it is an exercise that involves just one joint and one major muscle group. The participation of other muscles is going to be limited in isolation exercise. So, for example, the biceps curl is an isolation exercise because the only joint involved is the elbow and the biceps muscles do more or less all of the work. Let’s go over a few of the more common isolation exercises that you find in well-designed resistance training programs.

[00:10:36] Dumbbell Fly is an isolation exercise for the chest and it of course isolates the pecs. But it is limited by the fact that you really can’t use heavy weights without putting your shoulders at risk of injury. That said, it can have its place in a well-designed weightlifting program, but you’d usually find it later in a chest or push workout after the heavy compound work. You’d usually see it included just to rack up a bit more volume for the pecs.

[00:11:05] Another isolation exercise that you’ll find in many weight lifting programs is the dumbbell pullover. This exercise is famous because many bodybuilding legends like Arnold, Reg, Ronnie, and Dorian have credited it with helping them build their impressive chests. And research shows they were probably on to something like the dumbbell fly. The dumbbell pullover is an effective way to train the chest and it is also better suited to higher rep ranges and better done after your initial heavy pressing.

[00:11:41] The next isolation exercise that I want you to know about is the lateral raise because it is one of the few that I think belongs in every bodybuilding program out there because it is the simplest and the best, the most effective, straightforward way to train your side deltoids which will fall behind your anterior, your front deltoids if all you do is a bunch of shoulder pressing and chest pressing.

[00:12:12] Another isolation exercise that you will come across often is the front raise, the dumbbell front raise. Sometimes also a barbell front raises, but usually dumbbell front raise. And it’s a simple exercise that isolates the anterior deltoid. And although it can’t deliver the same results as dumbbell and barbell pressing, it can have its place in a workout program and it is better suited to lighter, higher rep work.

[00:12:39] Next up is the cable straight to arm pulldown and you don’t see many people doing this, but it is one of the few isolation exercises that allow you to isolate your lats. I’ve actually done a fair amount of this exercise over the years because for a while my lats were woefully lacking.

Despite being fairly strong in my pulling, fairly strong and my deadlifting, my barbell rowing, dumbbell rowing, my lats were just very stubborn. And so for some time I was ending my pull workouts with some straight arm pulldowns and was, if I remember correctly, I think I was also doing a few sets a few days later as well.

[00:13:21] All right. Next up is the biceps curl. I mentioned this earlier. Simple, effective exercise for building bigger and stronger biceps. End of story.

[00:13:29] Leg extension is another isolation exercise that is popular but that I’m not a big fan of because it places a large amount of stress on your knee joints and your ligaments. And it’s also not very effective as a quadriceps exercise. It’s okay if you are going to use lighter weight and do more reps, but as far as an exercise for achieving progressive overload over time, not very good.

[00:13:57] All right. The next isolation exercise on the list is the leg curl. And I like this exercise. I think it’s a very worthwhile addition to your lower body workouts, especially if you are doing a lot of squatting, back squatting, front squatting, a lot of leg pressing, and other exercises that really hammer the quads. It is a good idea to balance that out with some hamstring specific work. And the lying leg curl, for example, is one of my favorite hamstring isolation exercises for doing that.

[00:14:29] All right. Next on the list is the calf raise and calves. Oh yes, my favorite thing. Calves are like abs. Some people just come with them and some people have to work very, very hard to have anything to show. And of course, I’m in the latter camp. Calf raise is the easiest way to isolate the calves and should be used when necessary.

Some people say standing calf raises are the best. I would say that they do feel a bit more effective than the seated. I also like doing calf raises on the leg press and also the hack squat sled can work as well. It’s kind of like a half standing, half seated type of position for the calf raise.

[00:15:08] So isolation exercises, there we go. As you can tell, then you have these movements that have you raise, curl, and extend a limb. And these are generally isolation exercises. Now, these exercises are more suited to lighter weights and higher reps, at least for the most part, which makes them good for periodization and for controlling your workout volume, which we will talk more about in a minute.

[00:17:08] All right, so now let’s flip back to compound exercises and talk about advantages. What are the advantages of compound exercises?

[00:17:13] Well, one of the biggest fitness mistakes that people make is underestimating the importance of compound exercises. I should know this because I had to learn this lesson the hard way when I first started lifting weights. I followed bodybuilding magazines really for both my diet and my training. So I ended up eating a lot more food and protein in particular than was really necessary.

And I was doing a lot of long two-plus hour high rep, high volume, multi exercise workouts consisting mainly of isolation exercises to really hammer individual muscle groups. So it’d be a body part split, it’d be a chest Monday, and then a lot of isolation exercises to really hammer the pecs.

And after seven years or so, I had gained a fair amount of muscle, maybe 30-ish pounds, which sounds decent, but not for seven years. The average guy should be able to gain 30 pounds of muscle, probably in his first three years, really. And I also had a high responding chest and high responding biceps, so I looked more jacked than I really was.

Again, I looked pretty good, but honestly, I expected more from having put so much time in the gym. Then, though, eventually, I threw away the magazines, I stop buying all the goofy supplements, and I got serious about educating myself. I changed the way that I ate, I changed the way that I trained, and a few years later, I looked quite a bit better.

And I wanted to continue gaining a bit of size, though, and bring up what I felt were some weak points in my physique, particularly my shoulders and lats. And so I applied my barbell, my dumbbells, and my forks and knives for another year or so and more or less had then the physique that I have now.

I’ve gained a bit more muscle since then, but not much has changed because at that point I really had reached the top of my genetic potential. Maybe I could gain another five, six, seven pounds of muscle if I were to really go for it. But it would take a couple of years and it would take a lot of hard work. Not that I mind the hard work, but I’m pretty happy with where things are at right now.

[00:19:31] So what does all that have to do with compound exercises? Well, one of the major changes that I made in my training that helped me get to where I am now was shifting my focus from isolation to compound exercises. And there are several reasons for this. One is: compound exercises train many muscles at once.

And the more muscle groups you can effectively train in a given exercise, the more overall muscle you can build as a result. This is also more time-efficient, obviously, because one compound exercise can do the work of several isolation exercises.

[00:20:07] Another big benefit of compound exercises is they allow you to lift heavier weights. Best compound exercises put dozens of major muscle groups and multiple joints through a large range of motion, and consequently then, they enable you to move more weight than isolation exercises. And that allows you to better progressively overload your muscles over time.

Now, that is significant, of course, because mechanical tension, the amount of tension generated in your muscles is the primary driver of muscle growth outside of some hormonal stuff that goes on in the body. But it’s the primary factor in terms of what you are doing in the gym.

And your goal then is to increase the levels of tension produced in your muscles over time. And the most effective way to do that is to get stronger over time, to add weight to the bar over time. And that is progressively overloading your muscles over time.

[00:21:02] Compound exercises also do significantly raise testosterone and growth hormone levels because the amount of muscle that is involved in the workout directly impacts the magnitude of post-workout elevations in anabolic hormones. And that’s why research shows that compound exercises do produce larger increases in both testosterone and growth hormone than isolation exercises.

[00:21:31] Now, that sounds cool, but you should know that studies do show that these effects do not influence muscle gain nearly as much as some people would have you believe. In fact, it may have little to no effect on long term muscle gain, but there are other benefits to regularly elevating anabolic hormone levels.

So the bottom line here is: I attribute much of my success with my physique to the fact that after learning about the power of compound exercises, I made them 70 to 80 percent of the work that I was doing in the gym.

[00:22:07] And that’s still the case today, several years later. The majority of the hard sets that I do every week are of compound exercises. I still do isolation exercises, but I know which side my bread is buttered on. Another major change to my training was the emphasis of heavy weight lifting, of lifting weights somewhere in the range of 80 to 90 percent of my one-rep max.

Previously, I would spend much of my time in the gym chasing a pump with fancy techniques like drop sets, supersets, and giant sets. And while those things do have their uses, they should never be the focus of your workouts like they were for me years ago. Instead, your approach should be simpler.

Your focus should be using heavy weights, anything from, let’s say, 4 reps up to 12 reps, and you should be working to add weight to the bar over time. Increase whole-body strength. That is the primary goal. So when you combine that with sufficient weekly volume, which the long story short is anywhere from 10 to 20 hard sets per major muscle group per week is plenty of volume.

You do not need to go beyond that. You can make steady progress in both muscle and strength gain and over time reach your genetic potential as well. I would give yourself at least five years of doing everything right to even approach it. And some people say it takes more like 10 years of dedicated proper training to really max out your genetic potential.

[00:23:47] All right. So now let’s talk about isolation exercises. What are the advantages of isolation exercises?

[00:23:53] Now, many people, many strength people in particular, would tell you that isolation exercises really don’t have any place in a real weightlifting program, that all you need to do to build a great physique and to get super strong is just squat, deadlift, and bench overhead press. End of story. And I disagree. The first thing that you must understand is every compound exercise has a prime mover.

That is the star of the show. It has a primary major muscle group that will benefit most from it. And then there are secondary, kind of assistant muscle groups, that can benefit as well, but not as greatly as the primary ones. And what that means then, is that compound exercises can create imbalances in the growth in the portions and symmetry of various muscles that are involved.

For example, if all you did for leg training was front squats, you would probably develop an imbalance between the strength and size of your quadriceps, those are the prime movers. And your hamstrings, those are the secondary movers. You will probably also develop an imbalance between your right and left legs because invariably you are going to, over time, come to favor one side, probably your dominant side over the other.

And if you repeat that enough, eventually the side that you are favoring, even if it’s just slightly, over time, gets a little bit bigger, a little bit more defined, a little bit stronger than the other side. Now, if you didn’t address this issue at all, let’s say you didn’t address the imbalance between the quads and the hamstrings in particular. That issue can increase the risk of hamstring injury, it can increase the risk of developing knee problems, and other undesirable things.

[00:25:43] Another good example is the shoulder development of someone who has done nothing but overhead and bench pressing. And what’s usually missing is the round kind of capped look that really frames the upper body and makes the shoulders look like they’re just kind of popping off of the arms. And to understand why you need to first know that the shoulders consist of three muscles.

The deltoids, right? So you have the anterior front deltoids, you have the lateral side deltoids, you know, the posterior rear deltoids, and when you overhead press the anterior deltoids, the front, are the protagonists. And the lateral deltoids only assist and the posterior deltoids aren’t really involved at all.

Now, that is significant because it’s those latter two muscles, the side and the rear delts that mostly determine how three dimensional our shoulders look. Not the anterior deltoids. So what can happen then is you can have a very strong overhead press, so you have very strong front deltoids, but rather underwhelming shoulder development on the whole.

And this is where isolation exercises like these side and rear lateral raises can save the day. They allow you to train, to focus on, to isolate those small, hard to activate muscles in your shoulders, and help bring them up to snuff.

[00:27:04] Another benefit of isolation exercises is they allow you to better control the total amount of volume, the total amount of hard sets that you’re doing every week for each major muscle group. Now when we’re talking weight lifting, volume can mean different things to different people. Some people think of volume as the number of reps performed.

Some people think of it as the amount of weight moved. So you have the weight of the set and then you have the number of reps and you multiply those together and that’s the volume of the set and so forth. I like thinking of it as just hard sets. Sets where you are taking them close to technical failure, those are your muscle-building sets. So we think of that as volume.

[00:27:45] Now, if volume is too low, if you are doing too few hard sets per major muscle group per week, you will struggle to gain muscle and strength. You’ll do fine at first, but then you’ll plateau basically. And if your volumes too high, you can run into many different problems. Your risk of injury goes up, your risk of developing symptoms related to overtraining goes up.

But if you get volume right, you can work in a sweet spot of sorts that allows you to gain muscle and strength over time without compromising your health and safety. I mentioned earlier that optimal volume is somewhere in the range of 10 to 20 hard sets per week. And if you are new, you could start with 10. And if you’re very experienced, you’d want to work up toward 20.

Now, that doesn’t mean you have to do that for every major muscle group, of course, it also depends what you want to do with your body, and what muscle groups need the most attention, and how much time you have and so forth. But generally speaking, that’s a good rule of thumb.

[00:28:44] So isolation exercises are very helpful with volume because they allow you to increase volume on specific muscle groups without much-impacting others that you want to leave alone, that you want to rest, that you have already put your hard sets in on. And this helps you better program your workout routine to avoid under or overworking certain muscle groups.

So, for example, the dumbbell side lateral raise allows you to increase your volume on the lateral deltoids without putting much stress on the other muscles in your shoulders. The chest fly allows you to increase volume on the pecs without much involving the shoulders or triceps. The front raise allows you to increase volume on your front deltoids without involving the triceps.

The hamstring curl allows you to increase volume on your hamstrings without engaging the quads. The leg extension reverses that. It isolates the quads without involving the hamstrings. And then you have biceps, triceps, and calf exercises which are all isolation movements and are really the only way to directly train those muscles without increasing the volume of larger muscle groups as well. 

[00:30:01] And that is why many well-designed weightlifting routines include both compound and isolation exercises. In many of these routines, you have compound exercises forming the foundation. Those are the ones that are used to directly train and overload the major muscle groups and really are the focus and primary benchmarks of progression.

But then there are also isolation exercises that are included to further develop specific muscle groups that are not sufficiently trained by the big compound exercises, but that do greatly contribute to your overall appearance.

[00:30:41] So to summarize, no matter how you look at it, compound exercises do deserve more of your attention than isolation exercises. If your goal is to improve athletic performance if you want to run faster, jump higher, be more explosive and so forth, compound exercises are going to deliver better results than isolation exercises.

If your goal is to improve your whole-body strength, then you actually may not need to do much isolation work at all, at least until you become a more advanced weightlifter on the big compound movements. And if your goal is just to build muscle and look good, then you will get their quickest by focusing most of your efforts on the big compound exercises and then supplementing them with isolation exercises where needed.

And if you are wondering when you might want to emphasize isolation exercises, well, often it’s when there is an injury involved or maybe age and joint issues. But even then, there are often cases where compound exercises are the better choice.