3 Types of Muscle Contractions

Watch the video for the TLDR version of this blog post!

Muscles are the unsung heroes of our body, enabling us to perform a myriad of movements and actions. When we think about muscle contractions, most of us picture the classic image of flexing our biceps, but there's much more to the story. There are three main types of muscle contractions: concentric, eccentric, and isometric. Each type serves a unique purpose in facilitating our movements and maintaining our body's stability. In this blog post, we'll delve into the intricacies of these muscle contractions and understand how they contribute to our everyday activities.

Concentric Muscle Contractions

Concentric muscle contractions are perhaps the most recognizable type of contraction, often associated with traditional strength training exercises. These contractions occur when a muscle shortens as it generates force against a resistance. In simpler terms, this is the phase when a muscle contracts and visibly bulges as it overcomes a load. Picture the upward movement of a bicep curl: as you curl the weight towards your shoulder, your bicep muscles are undergoing concentric contractions.

During concentric contractions, muscle fibers pull together, causing the muscle to shorten. This shortening action is what enables us to lift objects, perform repetitive motions, and engage in activities that require pushing or pulling. Common examples of concentric contractions include pushing a door open, lifting weights, and performing a sit-up.

Eccentric Muscle Contractions

Eccentric muscle contractions occur when a muscle lengthens while under tension, usually as it resists a force that is greater than the force being generated by the muscle. In other words, the muscle is still contracting, but it is lengthening at the same time. This is often referred to as the "negative" phase of an exercise. During eccentric contractions, the muscle is controlling and slowing down the movement, rather than actively creating it.

Eccentric contractions play a critical role in muscle development and strength gains. They create microscopic tears in the muscle fibers, which then repair and grow stronger during the recovery phase. For instance, when you lower a dumbbell during a bicep curl, your bicep muscles are undergoing eccentric contractions. Walking downhill, lowering yourself in a push-up, and descending stairs are also examples of eccentric muscle actions.

Isometric Muscle Contractions

Unlike concentric and eccentric contractions, isometric contractions don't involve visible movement of the joints or muscle length changes. Instead, these contractions occur when muscles generate force without changing length. Essentially, the muscle tenses and holds a static position against a resistance.

Isometric contractions are crucial for maintaining posture and stability. Think of holding a plank position or pausing halfway during a squat. In both cases, your muscles are exerting force without any change in joint angle or muscle length. Isometric contractions are also used in activities like pushing against an immovable object or gripping something tightly.

Isometric work is excellent during an injury or for tendon rehabilitation.

If you want to get a tailored exercise program to improve your performance and health, book here or give us a buzz on 0402 832 329.