1. Muscles As you are responsible for running a warm- up by now you should know the names of the muscles you stretch every week! See if you can identify the 11 muscles of the body you need to know for GCSE PE.

2. Deltoids Biceps Deltoids Abdominals Quadriceps Pectorals Trapezius Triceps Gluteals Hamstrings Gastrocnemius Latissimus Dorsi

3. Muscle Functions 1.Production of Movement –Movement of the body through the pulling action of muscles at a joint –Movement of blood through the heart and the circulatory vessels. –Movement of food (and, subsequently, food waste) through the Digestive System

4. Muscle Functions 2.Posture (the way you sit or stand)of posture –Muscle contraction is constantly allowing us to remain upright. –The muscles of your neck are keeping your head up right now. –Having good muscle tone means that we aren’t flabby and slouch when sitting. 3.Production of Heat –Occurs via shivering – an involuntary contraction of skeletal muscle. More commonly heat is produced when we exercise as fuel is ‘burnt’ within the muscle cells.

5. Skeletal Muscle Attachments How are our muscles connected to our bones? Most span joints and are attached to bones. –The attachment of the muscle to the immoveable bone in a joint is its origin, while the attachment to the moveable bone is its insertion.

6. Oxygen Debt Refers to the fact that after intense exercise our breathing rate remains fast even after we stop. We continue to breathe hard because our body: –Needs to take in more O 2 to flush out Lactic Acid –The energy stores used during exercise in our muscles need to be replaced. Oxygen helps our muscles to replace these energy stores faster.

7. Other Important Terms Cramp –A prolonged spasm that causes the muscle to become taut and painful. Hypertrophy –Increase in size of a muscle In muscles, hypertrophy is always due to an increase in the intensity of your training, eg lift heavier weights, for longer periods or more training sessions per week. Atrophy –Reduction in size of a cell, tissue, or organ In muscles, its often caused by disuse. Why might Sportsmen suffer muscle atrophy? Stretch the muscle to relieve cramp. Muscles respond by getting larger when they are placed in Overload due to exercise. Muscles that do not get exercised often waste away ….