Muscle contraction is the tightening, shortening, or lengthening of muscles when you do some activity. It can happen when you hold or pick up something, or when you stretch or exercise with weights.

If your fitness goal is to up the ante on endurance, pack more power into your sprint, or supercharge your strength gains in the gym, it’s worth exploring – what are the different muscle fiber types?

Skeletal muscle is the type of muscle that controls movement. Problems with these muscles can be minor, life-threatening, or ongoing problems that make it hard to perform basic daily activities.

Muscles and nerve fibers allow a person to move their body and enable the internal organs to function. There are more than 600 muscles in the human body. People also have different types of muscle. A ...

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Fast twitch muscles help with sudden bursts of energy involved in activities like sprinting and jumping. Twitch muscles are skeletal muscles that help support your movement. They’re especially ...

You have 3 different types of muscle: skeletal, smooth, and cardiac. Skeletal muscle alone accounts for over 650 different muscles. Have you ever wondered how many muscles you have in your body? The ...

What's the first thing that comes to mind when you think about the words twitch and muscle? Spasms, perhaps. You'd hardly be alone in thinking that. But when it comes to fitness, it's most commonly ...

Most fitness-minded people have probably heard of fast- and slow-twitch muscle fibers. However, the distinction can be somewhat mysterious, especially in the context of understanding how it relates to ...