Powerful teen muscle

Your brain and powerful teen muscle tell these muscles what to do without you even thinking about it. Skeletal muscles are voluntary muscles, which means you can control what they do. Muscle building for Female bodybuilding Female muscle art Bodybuilding Stars.

Even the smallest movement can turn a smile into a frown. You can't use your smooth muscles powerful teen muscle make a muscle in your arm or jump into the air. You'll find smooth muscles at work behind the scenes in your eyes, too. You can't control this type of muscle.

The thick muscles of the heart contract to pump blood out and then relax to let blood back in after it has circulated through the body. In your stomach and digestive system, they contract powerful teen muscle up and relax to allow food to make its journey through the body. Thousands, or even tens of thousands, of small fibers make up each muscle. Tendons are cords made of tough tissue, and they work as special connector pieces between bone and muscle.