Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
The Muscular System KEY FILLED IN The Muscles Every movement that takes place in your body depends on muscles. They work by shortening or contracting. There are 3 kinds of muscles. 1. Involuntary (smooth): CONTRACT SLOWLY AND SMOOTHLY, YOU CANNOT CONTROL THEM, CAN REMAIN CONTRACTED FOR LONG PERIODS OF TIME. ESOPHAGUS, INTESTINES, OTHER INTERNAL ORGANS. 2. Cardiac Muscle: YOU CANNOT CONTROL THEM, WORKS 24/7, STRONGEST TYPE OF MUSCLE. MUSCLE OF THE HEART 3. Voluntary Muscles (skeletal/striped): YOU CAN CONTROL THEM, OVER 400 IN YOUR BODY, THEY MOVE YOUR FACE, BONES AND EYES Major Muscle Groups Deltoid- SHOULDER Bicep- FRONT PART OF HUMERUS Tricep – BACK PART OF HUMERUS Abdominals – MIDDLE OF THE STOMACH Pectoralis – CHEST Trapezius – LOWER NECK/ UPPER BACK Latissimus dorsi- MIDDLE/ LOWER BACK Quadricep – FRONT PART OF THIGH Hamstring – BACK PART OF THIGH Gluteus – BEHIND Calf – LOWER LEG Achilles – ATTACHES CALF TO HEEL How Muscles Work Voluntary muscles produce movement by CONTRACTING and RELAXING. Muscles get SHORTER when they contract and LONGER when they relax again. All voluntary muscles are attached by tendons to bones. These points of attachment are called ORIGINS and INSERTIONS. Some muscles have more than one attachment at one end (this is an indication of strength of the muscle). Tendons Tendons attach MUSCLE to BONE. Ligaments attach BONE to BONE. As a muscle contracts, the tendons at each end of the muscle takes the strain. Tendons must therefore be strong enough to work under HEAVY LOADS and resist the intense, sudden muscular contractions involved in sport, e.g. throwing the JAVELIN. The tendon of origin resists the pull of the muscle whilst the tendon of insertion exerts the pull on the bone to which it is attached. This causes the joint to bend or straighten. Tendons are a CONNECTIVE TISSUE which have a less efficient blood supply than skeletal muscle. A thorough WARM UP will stimulate blood flow to the tendons and this will reduce the chance of INJURY to the tissue. One tendon that is prone to injury is the ACHILLES tendon. Muscles for Endurance and Power Fast and Slow Twitch Muscle Fibers There are two types of muscle fibers present in voluntary muscles. Fast Twitch Fibers Slow Twitch Fibers Fast Twitch Fibers FAST, POWERFUL CONTRACTIONS Slow Twitch Fibers CONTRACT MORE SLOWLY AND WITH LESS POWER THAN FAST TWITCH FIBERS Burn up their supply of oxygen usually within 10 SECONDS. They then have to use the body’s store of carbohydrates as a SHORT TERM energy source. (ANAEROBIC Exercise). Are able to REPLACE their oxygen supply while they are working. (AEROBIC Exercise) Tire QUICKLY Can function for LONGER periods of time Used for short term power and STRENGTH activities (anaerobic activities) Used for longer term ENDURANCE activities (aerobic activities). E.x. E.x. In many sporting events we often use both types of fibers at different times during the activity. Complete the table below showing examples of the use of both types of muscle fibers in different sporting activities. Activity Marathon Running Slow Twitch Most of the race Fast Twitch Sprint finish Effects of Exercise and Training on Muscles Skeletal muscle responds to training in two ways. 1. Voluntary muscles become STRONGER and more FLEXIBLE when they are exercised. This development of the muscle is known as HYPERTROPHY. When exercise STOPS due to injury or some other reason, muscles begin to lose the STRENGTH and MASS that was gradually building up during regular activity. This is known as ATROPHY (wasting of the muscle). 2. Different activities rely of different muscles and muscular requirement. With REGULAR training, muscles adapt well to the exercise that they are required to perform. In activities that involve HEAVY workloads, e.g. SPRINTING, new muscle fibers are GENERATED (muscle bulk) until the muscles are STRONG enough to perform the task.