Why Isolation Exercises Should Play a Supporting Role In Your Strength Routine

The word “isolation” might have a negative connotation—especially in the aftermath of the COVID-19 pandemic—but rest assured: isolation exercises have nothing to do with being alone.

Isolation exercises are actually all about singling out a particular muscle group. They don’t get praised as often as their counterparts, compound exercises, but they’re an important part of any training plan nonetheless. Isolation exercises allow you to be super intentional with your strength work, whether targeting a specific body part to make it bigger and stronger, balancing out your abilities, or rehabbing after injury. 

What counts as an isolation exercise, though? And how should you incorporate them into your routine? Here’s a full breakdown of isolation exercises, why they’re worth your time, and 10 to try in your next workout.

What Are Isolation Exercises?

“Isolation exercises concentrate the effort on one particular muscle group,” says Peloton instructor Rebecca Kennedy. They do this by limiting the movement to a single joint. (For this reason, they’re also called single-joint exercises.) Think of a bicep curl or a tricep kickback and how the only joint moving is your elbow. The goal is to spotlight one muscle group and ask it to work.

A caveat: It’s impossible to shut down every muscle in your body and only work one. Your body moves synergistically, and other muscles will jump in to help stabilize or assist in an exercise even when they’re not the focus. For example, in a bicep curl (a classic isolation exercise), your forearm muscles engage to hold the dumbbell in place, your triceps (on the back of the upper arm) work to slow or stop the movement, your upper back muscles hold your shoulder blades down and back, and your core engages to keep you from bending forward. That said, most of the burn you’ll feel from a biceps curl is in—yep!—your biceps and that’s where the real strength work is happening.

Compound vs. Isolation Exercises

Isolation exercises focus on one muscle group, while compound exercises do the opposite: “Compound exercises, also known as multi-joint exercises, recruit multiple muscle groups,” Rebecca explains. Think of a squat or a deadlift, for example. You’re bending at both your hip and knee joints, forcing muscles on all sides of your core, hips, and legs to fire up. Many functional strength training moves are compound exercises since we seldom isolate a single muscle group in our natural movements in real life.

Because compound exercises work more of your body, they require more effort and thus cost you more energy (i.e., burning more calories) compared to isolation moves, according to the American Council on Exercise (ACE). Exerting more effort also gets your heart rate up and imparts more cardiovascular benefits than isolation exercises, research shows. Isolation exercises may not get you breathless, but they will typically result in a pinpointed burn (and, over time, increased strength) in one section of your body, as well as these other perks.

The Benefits of Isolation Exercises

Beginner-Friendly

Isolation exercises are great for beginners since they can help build a strength base that makes compound exercises easier, says Tom Holland, exercise physiologist and author of The Micro Workout Plan. For example, if you have trouble doing push-ups, building strength in your triceps and chest muscles with easier isolation exercises can help you log that first push-up rep.

Not to mention, isolation exercises are often done on machines with a gentle learning curve, Rebecca says. Even free-weight isolation exercises are ideal for starting. Because fewer joints are moving, they’re less complex, and it can be easier to get the form right and feel the correct muscles working. “They can also be easier on the joints compared to compound exercises and have a reduced risk of injury,” Rebecca adds. 

Laser-Focused Strength Training

“Isolations are an excellent option when trying to grow a specific muscle group,” Rebecca says. Let’s say your goal is to build strength in your triceps. It would be more advantageous to work close to failure (that is, until you almost can’t do another rep) in a tricep kickback (an isolation exercise) than performing a chest press (a compound exercise) where the triceps aren’t the primary muscle worked, she explains. “In a chest press, the work is spread amongst the pecs, shoulders, triceps, biceps, serratus anterior, and core.”

Bring Weak Spots Up to Speed

Isolation exercises are often used in physical therapy environments as they allow you to build strength in one muscle that may need it more than others. For this reason, exercise pros will program isolation exercises for people rehabilitating an injury or who want to fix specific muscular imbalances, Holland says. For example, many runners and cyclists tend to be quad-dominant, meaning they have stronger quads than hamstrings and thus have imbalanced leg strength; isolation exercises targeting the hamstrings can help rectify this imbalance so your body moves more efficiently.

10 Isolation Exercises to Try

Rebecca recommends trying these isolation exercises which focus on specific muscle groups from your shoulders to your calves.

Biceps Curl

Bicep curls work your biceps brachii, the muscles along the front of your upper arm, which play an essential role in pulling objects towards you, picking up and carrying things, or pulling yourself up from a hanging position. They have two heads (or sections): one long and one short. The traditional biceps curl keeps the emphasis on the short head, the one that forms that nice little bulge when you flex.

Muscles worked: Biceps (short head)

Hammer Curl

Hammer curls are very similar to traditional biceps curls but add a twist of the wrist. They also work your biceps brachii but emphasize the long head of the muscle, which is underneath the short head in your arm.

Muscles worked: Biceps (long head)

Triceps Kickback

Triceps kickbacks are a fantastic exercise to target your triceps, the muscles on the back of your upper arm. This muscle has three heads (or sections). Kickbacks work all three, with a focus on the lateral head of the tricep. Strengthening the triceps can help you build strength to tackle compound exercises like push-ups, chest presses, and more.

Muscles worked: Triceps (lateral head)

Overhead Triceps Extension

The overhead triceps extension offers a great visual of an isolation exercise since your whole body is stacked in a line and only the very top joint moves. This exercise targets the triceps with an emphasis on the long head.

Muscles worked: Triceps (long head)

Skull Crusher

This last tricep move works the same muscles, but puts the work in the third and final head of the muscle: the medial head. If using two weights is too difficult, you can hold a single dumbbell horizontally between both hands.

Muscles worked: Triceps (medial head)

Hamstring Curl

Hamstring curls are one of the few exercises you can do to specifically target your hamstrings, the muscles on the back of your thighs. You’ll need to do this in a gym with a leg curl machine.

Muscles worked: Hamstrings

Standing Calf Raises

Your calves—the muscles on the back of your lower leg—aren’t just a vanity muscle. They help you walk, run, jump, and row with ease. They’re comprised of two different muscles, and one (the ​​gastrocnemius) is best targeted when your legs are straight.

Muscles worked: Calves (gastrocnemius)

Seated Calf Raises

Your other calf muscle (the soleus) is best targeted with your knees bent. This version of the calf raise is a true isolation exercise, focusing on just the soleus. You can do it using a seated calf raise machine at the gym or at home with free weights and a chair.

Muscles worked: Calves (soleus)

Front Raises

This isolation exercise targets a specific part of your shoulders called the anterior deltoids, aka from the muscles on the front of your shoulders.

Muscles worked: Shoulders (anterior deltoids)

Lateral Raises

Similar to front raises, lateral raises also target your shoulders but focus on a different part of the muscle: your lateral deltoids, aka the sides of your shoulders. 

Muscles worked: Shoulders (lateral deltoids)

How to Add Isolation Exercises to Your Routine

Just because isolation exercises are good doesn’t mean they’re the only type of strength work you should do. “Variation is one of the keys to success when it comes to exercise,” Holland says. “Performing a combination of both isolation and compound moves will reap the greatest rewards.” 

Compound functional strength moves, like those included in most of Peloton’s strength classes, should be the foundation of your routine, since they train your body in the way it needs to move during daily life. From there, you can sprinkle in isolation exercises to target particular muscle groups, depending on your goals. When in doubt, consult a personal trainer or physical therapist for more personalized guidance. 

When Should Isolation Exercises Be Used?

Most experts will instruct you to save isolation exercises for last—or at least after you’ve done more taxing compound moves. “Isolation exercises will ‘pre-fatigue’ smaller muscle groups; they are thus commonly performed after compound exercises,” Holland explains. This is especially true when lifting heavy or performing more advanced exercises.

Doing compound moves first will help you attack your heavier lifts with more energy and fresher muscles, but can also potentially result in more strength gains. A 2020 study compared the results from a 10-week program in which some exercisers did compound moves first, then isolation exercises, and another group of exercisers did the opposite. The group that did compound exercises first reaped slightly more significant strength improvements than those who did isolation moves first.

That said, “compound first, isolation second” is not a hard-and-fast rule. Depending on your workout program and goals, it can make sense to do isolation exercises like muscle activations first, as part of your warm-up, to prime the mind-body connection before tackling more demanding moves. 

Before you start overthinking it, take heart that the 2020 study found that as long as you have both compound and isolation moves in your routine, you will build strength.