Muscles

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As explained by Amy Balsinger of Davidson University, sarcomeres are the basic contractile unit of muscles. Each muscle fiber contains hundreds of sarcomeres, which are repeating subunits of myofibril proteins. Muscles contract by sliding the thin actin filaments and thick myosin filaments along each other.

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  • What happens when muscles get tired?

    Q: What happens when muscles get tired?

    A: According to Gatorade Sports Science Institute, muscles hurt when they tire due to the accumulation of lactic acid. Muscles produce energy by converting glycogen into adenosine triphosphate with the release of acid and carbon dioxide. Muscles tire quickly during heavy exercises causing a demand for more energy. When the amount of oxygen supply to exercising muscles is limited, aerobic respiration takes place, resulting in an acidic environment within muscle fibers.
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  • When will a woman's biceps start to grow?

    Q: When will a woman's biceps start to grow?

    A: Women are incapable of developing their muscles, including the biceps, to the extent of most men due to their lack of testosterone. A woman's biceps, however, can still grow larger and stronger through exercises, such as the dumbbell curl and the chin-up that target this muscle and related muscles.
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  • How many muscles move your hand?

    Q: How many muscles move your hand?

    A: According to Clinical Anatomy For Dummies, there are a total of 18 intrinsic muscles that work to move each hand. These muscles are in three groups: the thenar muscles, the hypothenar muscles and the interosseous muscles and the lumbricals.
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  • How many muscles does it take to smile or frown?

    Q: How many muscles does it take to smile or frown?

    A: It is difficult to say how many muscles it takes to smile or frown because all people make different expressions when smiling and frowning. What might be a thoughtful look for one person is another person's frown. The number of facial muscles present also varies between individuals.
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  • What are the differences in structure and function of the three main muscle types?

    Q: What are the differences in structure and function of the three main muscle types?

    A: MedlinePlus explains that the human body has three different types of muscles: skeletal, cardiac and smooth. These muscle groups have different functions, are located in different parts of the body and have different structures.
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  • What is enthesopathy of the hip region?

    Q: What is enthesopathy of the hip region?

    A: Enthesopathy of the hip is an arthritic disorder in the sockets of the hip bone that affects the tendons and ligaments that are attached there. This means that the connections are not working correctly or are damaged in some way, creating problems with the connecting tissues between the hips and other bones. This causes pain or difficulty while moving or walking.
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  • What is the function of the trapezius muscle?

    Q: What is the function of the trapezius muscle?

    A: The primary use of the trapezius muscle is to move the shoulder blades, twist head and neck, stabilize the shoulders, shrug and support the arms.This muscle is also considered as an accessory breathing muscle.
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  • What is the main function of the quadriceps?

    Q: What is the main function of the quadriceps?

    A: The quadriceps, also known as the thigh muscles, move the knee and the hip, and they prevent the knee from buckling. The quadriceps are engaged when doing squats, climbing stairs, standing up and walking.
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  • Why can't I sit cross-legged?

    Q: Why can't I sit cross-legged?

    A: According to Yoga Journal, sitting cross-legged requires flexibility in the hip joints, back and inner thighs, and pelvis. These muscles are all very strong and can take some coaxing before stretching and relaxing enough for this to be a comfortable seated position.
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  • What are fun facts about the muscular system?

    Q: What are fun facts about the muscular system?

    A: The muscular system consists of approximately 700 muscles that belong to one of three distinct categories: skeletal, smooth or cardiac. Skeletal muscles are attached to the body's skeleton and assist it in moving. Smooth muscles are found in the internal organs and help maintain normal functions such as bladder control. Cardiac muscle is only found in the heart.
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  • What does it mean if you can tie a cherry stem with your tongue?

    Q: What does it mean if you can tie a cherry stem with your tongue?

    A: If someone can tie a cherry stem into a knot with their tongue, that suggests they may be a good kisser due to the oral dexterity required to perform the feat. It is a common trick performed at bars due to the presence of Maraschino cherries as drink garnishes.
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  • What is the shortest muscle in the body?

    Q: What is the shortest muscle in the body?

    A: The stapedius muscle, which is the shortest muscle in the human body (at a mere millimeter in length), holds the stapes in place inside the tympanic cavity of the ear. The stapedius works in conjunction with the smallest bone in the body to aid the function of hearing.
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  • What is the tendon behind the knee called?

    Q: What is the tendon behind the knee called?

    A: According to the Cascade Wellness Clinic, the popliteal tendon is situated behind the knee. The tendon connects the popliteus muscle to the femur bone just above the knee.
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  • What muscles do crunches work?

    Q: What muscles do crunches work?

    A: The crunch exercise primarily works the rectus abdominis, transversus abdominis and oblique muscles. The rectus abdominis muscles form the six-pack and are located perpendicularly along the front of the stomach. These muscles are part of the core, which supports bending and standing up.
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  • How is oxygen transported to the muscles?

    Q: How is oxygen transported to the muscles?

    A: As with all tissues dependent on a vascular supply, muscles depend on red blood cells to transport oxygen to them. Red blood cells, in turn, rely on an oxygen transport protein called hemoglobin to carry oxygen to all parts of the body.
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  • How do muscles respond to exercise?

    Q: How do muscles respond to exercise?

    A: According to MedicineNet, muscles respond to exercise through contraction and resistance, both of which eventually result in increased muscular strength. Neural impulses direct fibers to contract, resulting in voluntary exercise. There are three different types of muscles that are worked during exercise, including skeletal, smooth and cardiac muscle, and each one responds differently to physical exercise.
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  • What muscles make you punch harder?

    Q: What muscles make you punch harder?

    A: Strengthening the upper arm, forearm, shoulders and chest muscles allows for a harder punch to be thrown. The back muscles play a part in how hard of a punch is thrown as well.
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  • What is the muscle that allows you to shrug your shoulders?

    Q: What is the muscle that allows you to shrug your shoulders?

    A: Shrugging of the shoulders is primarily accomplished by the upper region of the trapezius muscle. The upper trapezius extends from the shoulder blade up to the back of the neck and is a common target of weight training exercises.
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  • What body parts are used to extend the hip when climbing stairs?

    Q: What body parts are used to extend the hip when climbing stairs?

    A: The body parts involved in hip extension when climbing stairs are the torso and lower back, opposite leg, knee and ankle, and hip joints. Hip extension during stair climbing occurs when the opposite leg is raised to the next step.
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  • Where are your glutes located?

    Q: Where are your glutes located?

    A: The glutes, or gluteal muscles, are located on the back of the pelvis region in humans. These muscles combine with a layer of fat to provide a cushiony layer of flesh to sit on.
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  • How many muscles does it take to talk?

    Q: How many muscles does it take to talk?

    A: Four main muscles are required for talking. These are the thyroarytenoid muscles, or vocalis muscles; the posterior cricoarytenoid muscles; the lateral cricoarytenoid muscle and the interarytenoid muscle.
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