There are plenty of different terms and phrases that are used to describe your muscles during a workout. Even the most experienced lifters might not know what some of these mean, but if you’re looking to amplify your workouts, it’s important to incorporate the most effective moves possible.

Isotonic exercises are necessary for a balanced strength training regimen. Here’s everything you need to know about them.

What Should I Know About Isotonic Exercise?

When you’re completing a repetition of an exercise, there are three phases: the concentric, isometric, and eccentric phases.

The concentric phase is when movement is “created.” This is when a muscle shortens (or contracts) under a resistance load. During a squat, this is the portion of the move where you begin bringing your glutes closer to the floor.

The isometric phase is a transition point at the apex of the movement. In a squat, this is the lowest point of the move, right before you’re about to push yourself back to start. This is not an isotonic exercise – we’ll discuss the differences later.

Finally, eccentric movements occur as you move back to the starting point of a move. This is when the muscle is lengthened against a resistance load. During a squat, this is the portion of the move where you press yourself back into a standing position.

Isotonic exercise occurs during the concentric phase when muscles are contracted. The word itself means “same tension,” and it refers to the weight remaining constant as you contract a working muscle. In theory, almost every single exercise involves a muscle contraction.

What Is the Challenge of Isotonic Movements?

When you perform a bicep curl, push-up, deadlift, or any other type of movement, you’re incorporating an isotonic resistance during the concentric portion. Here’s the thing – typical resistance is not truly isotonic because of a few different factors.

The relationship between a muscle fiber’s length and the amount of force it can produce is called the “length-tension relationship.” It’s a term that refers to the amount of force a muscle fiber can produce at different lengths. Each muscle has an optimal point where it can exert the most force. But the further a muscle is stretched or shortened past this point, the less tension the muscle will experience.

Imagine a bicep curl again. The biceps are strongest when your elbows are bent at 90 degrees, and you can feel this, considering this is the toughest portion of the move. When you have your arms extended or bent past 90 degrees, your bicep muscle doesn’t contract as strongly and does not exert as much force.

This is to say that it is technically impossible to maintain the exact amount of tension on a muscle throughout the entire range of motion in traditional strength training.

How Can You Do Isotonic Exercise?

When you’re engaging in strength training or almost any form, you’re incorporating isotonic movements without even realizing it. Pressing the barbell towards the sky in a bench press or bringing the weights closer to the floor on a deadlift are just two examples of isotonic, concentric exercise.

However, due to the length-tension relationship, it’s impossible to engage in isotonic movements throughout the entire range of motion because the muscle relaxes at different points of the move. That said, there is a way to maintain the tension throughout the move.

Speede uses powerful AI to adapt to your muscle contractions. In isokinetic mode, the velocity of the motion remains constant while the resistance alters. In other words, the machine will change the weight throughout your movement to ensure maximum force is exerted on your muscles — even when your muscle is stretched or contracted past its optimal point.

This is one of the only ways to experience isotonic exercise. The resistance level adjusts automatically to ensure a safe yet highly effective workout experience.

Book a demo today to feel the difference and see how isotonic exercise can change the game.

How Do Isotonic Exercise and Isometric Exercise Compare?

Isotonic exercise sounds super similar to isometric exercise, but they’re pretty different in execution. While isotonic means “same tension,” the word isometric means “same length.” While isotonic exercises involve movement, isometric exercises require the opposite.

Isometric moves are static movements that contract your muscle without changing the length. Squat holds, wall sits, hollow-body holds, bridges, and planks are all examples of isometric exercises where the goal is to remain still the whole time. 

Isometric moves are low impact and stationary, so they are often recommended for people recovering from joint pain, surgery, or injury. While they are not entirely helpful for building strength, they can be very helpful for helping you gain stability in working muscles and joints. They can be incorporated in addition to isotonic exercises for the greatest benefit.

What Are Some Isotonic Exercise Examples?

You’re naturally incorporating isotonic movements into your day-to-day fitness routine without knowing. But you can maximize the concentric, or isotonic, portion of a move by spending more time in that phase.

For example, during a push-up, do a slow count to three during the concentric phase on the up off the floor before bringing yourself back down to the floor more quickly. This will focus your energy on the isotonic portion of the move where the chest muscle is being contracted.

Keep in mind that studies have found eccentric exercise to be more effective for muscle growth. This is the portion of the move where a muscle is lengthened against resistance. So you might see more results if you spend more time in the “negative” portion of a move, such as the downward portion of a push-up. This is because more force is being exerted on the muscle.

With that said, isotonic exercise can still help you achieve great muscle gains. The best workouts are ones that excite you and make you feel satisfied, so try to mix it up with different forms of simple moves to keep it fresh.

In Conclusion

Isotonic exercise refers to the concentric contraction of a movement where the motion is “created.” The goal is to try to keep the same amount of tension on a muscle throughout the entire range of motion.

However, it’s nearly impossible to accomplish this with traditional strength training due to the length-tension relationship. 

That’s where Speede changes the game. With our isokinetic mode, the resistance changes throughout the range of motion to exert maximum amount of force on your muscle at every given point of the movement. This prevents instances where the muscle relaxes past its point of optimal contraction. Of course, when you want to mix up your workout with more traditional isotonic exercises as well, our Standard Mode has you covered.

To feel the difference and see what an effective workout is truly like, click here to book a demo.

Sources:

Isotonic vs. Isometric Exercises | The Columbia Association

Isometric exercises: Good for strength training? | The Mayo Clinic

Concentric and Eccentric: Muscle Contraction or Exercise? | PMC.