Isolation Exercise Benefits and Drawbacks

Isolation exercises in weight training are exercises that involve only one joint and a limited number of muscles. This is in contrast with compound exercises, which target two or more joints and muscle groups.

Learn about the benefits and risks of isolation exercises and get tips for how to work your arms, legs, and core using basic gym equipment and weight machines.

Benefits

Because isolation exercises target just one muscle group, you can focus on good form and technique as you build muscle, which can help prevent pain or injury from occurring.

Most commercial weight machines that perform isolation exercises are found at gyms and health clubs, while others can be purchased for use at home. Each piece of equipment is designed for a specific isolation exercise that works to strengthen a targeted muscle group. The seat height and other adjustable settings need to be taken into account in order to perform the exercise correctly.

Many people choose to do a circuit training session and go from machine to machine, performing one isolation exercise after another. Common pieces of isolation exercise gym equipment include:

• Cable machine
• Curl machine
• Dumbbells
• Loaded barbell
• Smith machine

Bodybuilding

Advanced bodybuilders use isolation exercises to target muscles that aren't being worked to their full potential. Isolation exercises can help build more definition in an area that was overlooked by compound exercises, particularly when supersets (two or more consecutive isolation exercises) are performed.

Physical Therapy

Isolation exercises are often prescribed during physical therapy and rehabilitation to strengthen and stabilize muscles and joints. The physical therapist determines which muscles need to be strengthened after an injury, before and after joint surgery, or during rehabilitation after deconditioning.

Additionally, a person who has developed an imbalance by overdeveloping one muscle group might use isolation exercises to build the opposing muscle group. Overdevelopment can occur among athletes. It is also common following an illness, injury, or surgical procedure, since a person may be overcompensating on one side to make up for a lack of strength on the other. A physical therapist can prescribe specific exercises to help correct a muscular imbalance.

Risks

However, a drawback of isolation exercises is that they can also cause muscle imbalances. If one muscle group is well-developed but the opposite does not quite match its strength, the body is out of alignment. That's why it's important to make sure you work the antagonist muscle for every targeted muscle. A person who loves doing biceps curls and doesn't work their triceps may find themselves out of balance.

Keep in mind that no muscle moves completely isolated from the rest of the system. Synergistic muscles will also lend some assistance, stabilization, or neutralization of the movement of a muscle or joint. This is especially true if a person isn't using the correct form or hasn't set an exercise machine to their individual settings, which can lead to injury.

Isolation Exercises

Whether you're looking to sculpt and tone or increase muscle gain, a consistent strength training routine that includes isolation exercises is key. In general, curls, raises, flys, and extensions are all isolation exercises.

Try the following isolation exercises to target muscles in your arms, core, and legs. You might perform these one at a time or move through a circuit that includes most or all of them. Just remember to warm up properly before beginning isolation exercises and listen to your body while completing your workout.

Arms

• Biceps curls flex the elbow joint to target the front upper arm muscles. These can be performed with dumbbells, cables, or exercise machines.
• Chest flys are performed with a chest fly machine or with dumbbells to work the chest muscles.
• Dumbbell side raises target the lateral and anterior heads of the deltoids in the shoulder muscles to give you broader, stronger shoulders.
• Flat bench presses work the chest, triceps, and shoulder muscles and are performed lying supine on a weight bench with a barbell or set of dumbbells.
• Triceps extensions target the back of the upper arm as well as the shoulders and core. Also known as an overhead triceps extension, this exercise is performed with one or two dumbbells.
• Triceps kickbacks work the back of the upper arm and can be performed on a weight bench or knee-height platform with the body tipped forward and the shoulders at hip level. Alternatively, the exercise can be done standing in a split stance with the torso pitched forward at the hips.
• Triceps pushdowns use a cable machine or resistance band to develop the triceps.
• Wrist curls can be performed kneeling in front of a weight bench with the forearms placed face up while holding dumbbells to target the muscles in the forearms and wrists. 

Core

• Back extensions utilize a back extension machine or Roman chair to flex the waist and strengthen the muscles in the lower back. This move can also be performed as a bodyweight exercise without any equipment by simply using the upper body as the load. Proper form and technique are crucial for this exercise to avoid pain or injury.
• Machine crunches or sit-up machines target the abdominal muscles. When you sit at a crunch machine, you will hook your shins beneath the leg pads and reach for the handles above your shoulders as you crunch forward.
• V-ups target the abdominal wall while challenging balance. Also called a V-sit or V-situp, this move involves sitting with the legs extended and torso lifted as the arms reach out in front. From a V-shape, you can lower and lift for a series of repetitions. No gym equipment is needed for this core isolation exercise, though an exercise mat can offer support and stability.

Legs

• Calf raises are performed standing using dumbbells. This isolation exercise targets the gastrocnemius and soleus muscles, which run down the backs of the legs. These muscles are essential for ankle flexion and extension to propel running and jumping. 
• Hamstring leg curls are usually done with a curl machine to target the calf muscles and hamstrings.
• Quadriceps leg extensions are performed with a leg extension machine to target the quadriceps muscles of the front of the thigh: the rectus femoris and the vastus muscles. This isolation move is performed by sitting on a padded seat and raising a padded bar with the legs.

A Word From Verywell

Isolation exercises are a great complement to compound exercises for a well-rounded strength-training regimen. There are many types of isolation exercises to try, so if you're not sure where to start, consider working with a personal trainer who can help you develop a balanced circuit-training routine using different strength and resistance exercises to meet your fitness goals.

Always remember to listen to your body when performing isolation exercises. Focus on good form and technique to prevent injury, and stop any exercise if you start to feel pain. If you think you may have injured yourself from exercise, contact your physician who can refer you to a physical therapist for treatment.