Isolation exercises are single-joint exercises that only work one muscle group at a time. Some examples of isolation exercises are bicep curls, skull crushers, calf raises, and barbell shrugs.
The opposite of isolation exercises are compound exercises. These are big, multi-joint movements that work multiple muscle groups at the same time. Some examples of compound exercises are back squats, pull ups, push ups, and bench presses.
Isolation exercises are good for:
- Targeting specific areas of weakness: For example, if you are recovering from an injury and need to build up strength in the injured area, isolation exercises are a great choice. Some people noticed their dominant side is stronger than their non-dominant side, and isolation exercises can also help even them out.
- Targeting specific muscles for growth: If your goal is to get huge biceps, or a big booty, then isolation exercises targeting those areas will definitely yield more results than non-targeted compound exercises.
Isolation exercises are bad for:
- Losing weight: Isolation exercises do not burn a lot of calories, and are not intense enough to provoke an aerobic response by the body. If you are looking to shed body fat, isolation exercises are not for you.
- Functional fitness: Isolation exercises are not a good way to train for “functional” human movements such as sitting down/standing up, jumping, running, climbing, crawling, etc. That’s because most functional movements are compound (multi-joint). Thus, isolation exercises will not be a significant help in preparing you for the zombie apocalypse.
These are the weight machines in the gym that allow you to easily adjust weight by selecting notches, and are structured so that you don’t have to worry about form. Movements you do on the exercise machines are also isolation exercises, as they target single muscle groups and allow only a single plane of movement. Examples of weight machines are the ab crunch machine, and the leg abductor & adductors. The opposite of exercise machines are free weights such as dumbbells & barbells, which require knowledge about maintaining good form while you use them.
Exercise machines are good for:
- Beginners: If you have never strength trained before, then exercise machines are a great option to get you started. They provide instructions & structure so that you can’t “mess up” an exercise, while the easy adjustment of weight allows you to figure out your baseline of strength without risk of injury.
- Covering all the bases: Because most gyms arrange their exercise machines in a circuit, it’s really easy to start at one end, quickly move from machine to machine, and hit all of your muscle groups without having to put much thought or planning into the workout.
Exercise machines are bad for:
- Losing weight & functional fitness: Once again, exercise machines are mainly isolation exercises only, so they’re not very good for weight loss or functional fitness.
- Stability & control: Because of how structured exercise machines are, you don’t need to use your core muscles to stay stable & in position, the machine does all that work for you. For example, bicep curls with dumbbells requires you to engage your core to stay still & not flail or fall over while lifting. In contrast, the bicep curl machine lets you just sit there & not worry about stability or form.
Depending on your fitness goals, isolation exercises & weight machines may or may not be a good choice for you. If your fitness goal is mainly aesthetic, then isolation exercises are a solid choice for beefing up muscles & curves where you want them. Additionally, if you are just starting out on your fitness journey, exercise machines will help you get started on the right foot.
However, if you are looking to lose weight, or work on your functional fitness for that upcoming Tough Mudder race, a better option for you would be a combination of compound exercises and cardio activity.