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FITNESS Unit #4 Muscles & Flexibility. Review from Chapters 13-15. Muscular Fitness. Muscular Endurance: the ability of a muscle group to continue muscle movement over a length of time Muscular Strength: the amount of force that can be exerted by a single contraction of the muscle.
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FITNESS Unit #4Muscles & Flexibility Review from Chapters 13-15
Muscular Fitness • Muscular Endurance: the ability of a muscle group to continue muscle movement over a length of time • Muscular Strength: the amount of force that can be exerted by a single contraction of the muscle
Strength and Endurance • Benefits in improved appearance of obtaining muscular strength and endurance: • develop better posture • look firmer and trimmer • feel better
Muscular Achievements • Achievement of a good level of muscular fitness will: • reduce risk of muscle injury • increase capacity to perform daily tasks and activity by reducing fatigue • reduce bone and muscle loss as you age
Health related problems that can be avoided by muscular strength and endurance: • low back pain • abnormal movement due to muscular imbalance • poor posture due to muscular weakness • inability to function effectively on a daily basis • resistance to fatigue • muscular injuries
Muscle Basics • Muscle: bands of fibers which enable us to move • Cartilage: firm, elastic connective tissue • Ligaments: a strong band of connecting tissue that holds bone to bone • Tendons: tissue that attaches muscle to bone • Testosterone: a hormone which is partially responsible for muscle development
Muscle Fiber • Fast-twitch muscle fiber: a muscle fiber which has a low capacity to use oxygen and the ability to contract fast. The muscles are used for short and intense bursts of action • Slow-twitch muscle fiber: a type of muscle fiber having a high capacity to use oxygen, but slow contractile ability. The fibers are used in endurance activities. • Intermediate fast-twitch muscle fibers: a type of muscle fiber used in activities of high intensity and moderate duration
Muscle Growth • Hypertrophy: the increase in muscle fiber size as a result of strength training • Atrophy: when a muscle becomes smaller because of non-use
Types of Muscle Contractions • Concentric contractions: a muscle contraction in which one end of the muscle remains stationary while the other end pulls and turns the bone about the joint. Also known as a shortening contraction. • Eccentric contractions: a muscle contraction which involves a gradual release of the contraction; often called a lengthening contraction • Static contractions: when the muscle remains in partial or complete contraction without changing its length
Effects of Exercise on the Muscular System • Changes that take place as you exercise a muscle: • the size of the muscle temporarily increases as the blood flow to it increases • the body temperature rises, due to the increased activity in the muscle tissue • the increased temperature causes the muscles to become more flexible, able to contract and relax more easily and contract at a faster rate.
Muscular Changes • Changes that take place during muscular endurance activities: • the number of red blood cells increases • additional capillaries develop
Weight Training • Set: in weight training, a group of successive repetitions without rest • Spotter: someone who assists the weightlifter • Recovery time: rest between workouts
FIT for Muscular Endurance • for Strength: • 8-12 reps at 80% of maximum • for Endurance: • 12-20 reps for 3 sets at 30-50% of maximum
Safety precautions for weight lifting • Warm up properly before beginning the training programs • As you are learning new exercises when starting a weight training program, use low weights and high repetitions. • Properly secure barbell plates to prevent slipping. • Keep hands dry by using weight lifting gloves or carbonate of magnesia.
It is important to breathe rhythmically as you exercise to avoid increasing internal chest pressure, which can cause you to faint or damage blood vessels. • When lifting a weight from the floor, keep the weight close to your body. • Unless spotters are present, do not perform the bench press or any other lift where you could be “pinned” if you lose control. • For stability keep back straight and feet shoulder-width apart.
Execute each movement under control. • Moving through the joint’s full range of motion will increase flexibility and strengthen connective tissue. • Begin each workout by using the largest muscle groups, moving to the smallest. • Don’t train if you are ill or injured. • Use proper techniques on all lifts.
Lifts • Negative lifts are called: • Eccentric contractions – • negative work can help the lifter work a muscle that is weakened by fatigue or injury. • Positive lifts are called: • Concentric contractions
Types of Exercises • Isometric contraction: a static muscle contraction against an immovable resistance. The muscle length remains constant while muscle tension increases [wall push] • Isotonic contraction: a muscle contraction involving shortening and lengthening of the muscle and movement at a joint [free weights] • Isokinetic training: training in which the length of the muscle changes while the contraction is performed at a constant speed. The machine provides maximum resistance throughout the entire range of motion.
Flexibility • Flexibility: the ability of a joint and muscle group to move through a maximum range of motion • Hyperflexibility: slack, overstretched ligaments caused by improper exercises or injuries and result in too much motion in a joint • Range of Motion: [full] whenever a body joint moves to its full limit without undue stress • Stretching: extending the muscles • Stretch reflex: a painful muscle spasm which prevents the muscle from overstretching
Bone Structure • Hinge joint: a joint which permits only limited movement • Ball and socket joint: a joint in which the rounded head of one bone fits into the cup-like cavity of another bone and permits movement in any directions
Muscles and Tendons • Extension: the lengthening movement of muscles around a joint • Flexion: the bending movement of muscles around a joint • Muscle imbalance: occurs when one muscle group is worked much more than the opposing muscle group thus becoming much stronger
Flexibility Techniques • Static stretching: the slow and gradual movement of muscle and joint through a range of motion. The stretch position must be reached and held for several seconds. • Ballistic stretching: when the muscle is stretched by a bouncing or jerky movement
Flexibility Techniques • Dynamic stretching: a stretch in which the muscle is slowly and continuously lengthened for 15-30 seconds • Contract and reflex stretching: contracting a muscle before it is stretched. The person stretching performs an isometric contraction, while a partner provides resistance.
Benefits of Flexibility • wellness • prevention of low back pain • healthy joints • injury prevention
Factors that limit flexibility • bone structure • muscles and tendons • ligaments • fat • gender • injuries • low back pain
Safety precautions for stretching • perform stretching exercises within your own physical limitations • progression should be gradual • avoid ballistic stretching exercises which can cause damage to muscles, ligaments and tendons • partner stretching can be dangerous if your partner forces you body to stretch too far