Biomechanics The study and the application of principles of physics to human motion. Understanding biomechanics can help you avoid fitness-related injury or soreness. The laws of biomechanics dictate that when you jog slowly, your foot strikes with a force that is 3 to 5 times your body weight.
Correct Jogging Form Head up Arms, shoulders, and neck relaxed Elbows flexed around 90 º Arms swing forward/back not side/side Heel strikes ground first Push off the ball of your foot Do not pound noisily Develop a smooth, even stride that feels natural to you255
Common Fitness Injuries & Treatment Skin Injuries ▫Blisters – caused by excessive friction Common when you first start conditioning Prevented by gradually breaking in shoes and wearing socks that fit well Muscle Injuries ▫Muscles cramp – painful spasms that occur during activity Associated with dehydration or mineral imbalance Common cramp in sides of abdomen = side stitch Apply moist heat to affected area to treat
Common Fitness Injuries & Treatment Connective Tissue Injuries ▫Tendons – bands that connect muscles to bones Shin Splints ▫Ligaments – bands that connect bone to bone and limit the movement of joints A pull or rip in muscle or tendon = Strain A tear = Sprain ▫Cartilage – tissue that prevents bones from rubbing together
Treatment for Connective Tissue Injuries RICE ▫R – Rest the injured area ▫I – Ice the area ▫C – Compress the area by wrapping it with elastic bandage ▫E – Elevate or raise the body part
Injuries to Bones Stress Fractures ▫A break in the bone caused by overuse ▫Pain above and below the crack in the bone ▫Tender to touch ▫Over time the fracture will worsen (4 to 6 weeks) ▫May not be detected on x-ray
Preventing Injuries Include proper warm-up and cool-down Progress slowly, but steadily Wear appropriate shoes and clothing Limit jogging on hard surfaces Use correct jogging form When jogging/walking always FACE oncoming traffic Postpone activity when you feel sore or fatigued
Tobacco – CNS Stimulant Smokers are 3 to 5 times more likely than nonsmokers to experience shortness of breath during exercise Smokers are prone to more coughs/lung infections, which can hamper a daily routine Long-term use of tobacco can lead to elevated heart rate and blood pressure
Alcohol – CNS Depressant Long term drinking increases the risk for high blood pressure, heart rhythm disorders, heart muscle disorders, and stroke. It is also associated with many cancers and liver disease. In teens, alcohol can interfere with growth & development.
Anabolic Steroids Non-medical steroids are illegal and dangerous Taken as pills or injections Effects ▫Males – lower sperm count, increased risk of prostate/testicular cancer, larger breasts ▫Females – infertility, deeper voice, more facial hair, smaller breasts ▫Both males/females – hair loss, acne, sleep problems, upset stomach, rapid weight gain, difficulty urinating, erratic mood swings “roid rage” can result in violence
Chapter 3 Section 1 Health–Related and Skill-Related Fitness
Health-Related Fitness 5 Components of Fitness ▫Body Composition – relative percentage of body fat to lean muscle mass ▫Cardiovascular Fitness – ability of heart and lungs to work together for extended period of time ▫Muscular Strength – maximum amount of force a muscle can exert ▫Muscular Endurance – ability of muscle to exert a force over an extended period of time ▫Flexibility – ability to move a body part through its full range of motion
Presidential Fitness Testing Body Composition = Height/Weight = BMI Cardiovascular Fitness = One mile run Muscular Strength – Pull-ups/flexed arm hang Muscular Endurance – Sit-ups Flexibility – Sit and reach
Skill-Related Fitness 6 components or measures ▫Agility – ability to change direction ▫Balance – ability to stabilize the body ▫Coordination – ability to use the senses to direct movement of the limbs ▫Speed – ability to move swiftly ▫Power – ability to apply maximum force of muscle ▫Reaction time – ability to react/respond quickly
Skill-Related Fitness Tests Agility – Cone Drill Balance – One foot stand test Coordination – Foot/ball volley Power – Standing long jump Speed – 50 yard dash Reaction – Yardstick drop