In the gym, you will hear a lot about forms of muscle contraction such as Eccentric, Isometric, or Concentric. So what do these concepts mean, let’s find out with Fitness Channel.
There are three main types of muscle contractions commonly encountered in exercise: isotonic, isometric, and isokinetic. In addition, they are also divided into concentric and eccentric depending on whether the muscle is shortened or lengthened.
What is Isotonic muscle contraction?
Isotonic muscle contractions are movements in which the muscle changes length as it contracts. Weight or resistance level remains the same. There are two types of Isotonic muscle contractions:
Concentric – Concentric contraction
Concentric contractions (or radial contractions) are contractions that shorten the muscle when it contracts or, in other words, the muscle produces a force stronger than the external resistance to pull the contracted muscle toward center.
An example is bending the elbow from straight to fully flexed, causing a concentric contraction of the brachii biceps muscle. Concentric contractions are the most common type and occur frequently during daily activities and sports.
Common Concentric movements include:
What are the benefits of Concentric training?
While Eccentric exercises help increase muscle size, Concentric exercises stimulate muscle strength.
This makes them especially important for endurance, resistance to fatigue, and improved performance in movements like running or swimming.
To focus on the Concentric exercise, you can spend more time on the part of the workout where you’re strengthening or shortening your muscles and less time on the Eccentric part of the movement, which helps build strength. , speed and power . However, this exercise will not strengthen the muscles as much as the Eccentric exercise.
It’s helpful to understand that in order for muscles to get stronger, you actually need to damage the muscles. You need to create micro-tears in the muscles for the body to repair and regenerate even stronger than before.
Concentric movements do not damage the muscle like many Eccentric movements. While this means less power gain per rep, it also means less soreness and faster recovery.
Eccentric – Eccentric contraction
Eccentric (eccentric contraction) is a type of muscle contraction opposite to Concentric (concentric). They occur when the muscle lengthens when it contracts, in other words, the resistance from the outside is stronger than the tension of the muscle causing the muscle bundle to relax, thereby lengthening the muscle.
This happens when lowering the dumbbells in the Bicep Curl exercise. The muscles are still contracting to keep the weight down but the biceps are lengthening.
Another example is the muscle before landing from a jump. When you land, the thigh muscles and especially the front thigh muscles of the leg are contracting strongly but also lengthening.
This type puts a lot of strain on the muscles and is often associated with muscle injuries. Plyometric exercises involve a lot of eccentric contractions and can lead to late-onset muscle soreness (DOMS) if you do them too early.
What are the benefits of doing Eccentric exercises?
A common example can be seen in the Biceps Curl move. The off-set portion of the movement is while you’re lowering the dumbbells slowly and with control.
To really increase the effectiveness of this part of the exercise, you can lengthen this part of the movement and keep the descent smooth and extended. This section is called Tempo in Workout which you can read more about here.
Eccentric contractions strengthen your muscle fibers, making it one of the most effective parts of the exercise to stimulate growth in size.
However, Eccentric training places greater demands on your muscles and central nervous system, and may take longer to recover from.
NOTE: Eccentric movements do more damage to your muscles than Concentric movements. In addition to strengthening muscles, Eccentric training helps strengthen tendons and ligaments, helping to reduce the risk of injury.
Examples of Eccentric workouts include:
- Slowly bring the bar back to the floor from a standing position while deadlifting while counting to four
- Lower from the bar (when pulling up the bar) VERY SLOWLY
Isometric – What is isometric contraction?
Isometric contraction occurs when there is no change in the length of the contracting muscle. For example, when carrying an object in front of you. The weight of the object pulls your arm down, but your muscles contract to keep the object from falling.
Isometric exercises can be mentioned as
- Handstand hold
- High plank
- Wall sit
- Hollow hold
- Hanging from the pull-up bar
- Front rack kettlebell hold
What are the benefits of practicing Isometric?
One of the biggest advantages of isometric exercises is that holding the pose still requires you to really engage your core (squeeze). Isometrics can be used to increase balance and body control, while allowing participants to explore and feel the proper position.
Isometrics can also help you overcome the threshold of strength.
For example, we tend to be weaker on the last range of movement. For example, think of the Back Squat: when pushing the weight up, the deepest position of the squat is usually where most people struggle to do it. But sitting at the lowest position in a squat with a heavy barbell on your back can help you develop the strength you need to get up again.
The same concept applies to push-ups or bench presses. Keeping your body an inch or two off the ground while doing push-ups will make the whole movement easier. What this does is focus more on the muscles, which helps promote muscle growth.
Isometrics and trauma recovery
Another great application of isometric exercise can be seen during injury recovery. And sometimes isosmetric exercise is the preferred method many physical therapists use to get their clients back on track.
Benefits of Isometric Exercises for Injury Recovery
There are many benefits to using isometric exercise after injury or surgery. They may include:
- You can safely contract your muscles while protecting your surgical incision or sensitive area.
- Your muscles can be strengthened in a very specific range of motion around the joint. This can assist with proper joint movement during rehabilitation, or reset or recreate motion after an injury.
- No special equipment is required to perform isometric exercises.
- To help increase activation and input for a specific muscle.
What is Isokinetic muscle contraction?
Isokinetic contractions are similar to Isotonic in that the muscle changes length during contraction, their difference is that Isokinetic contractions produce movements at a constant rate.
To measure this, a special device called an Isokinetic dynamometer is required. Examples of the use of Isokinetic contractions in everyday activities and sports are rare. The easiest example is breaststroke in swimming, where the water creates constant resistance, even to the movement of introduction.