KIN 122 1st Edition Lecture 3 Measurement Direct measure laboratory test measuring the exact thing you are trying to assess Indirect measure field test measuring something else as a measure of the thing you are trying to assess What is fitness A set of attributes that people have or achieve that relates to the ability to perform physical activity Remember NOT a behavior A characteristic of a person Two types Skill related fitness Health related fitness 1 Skill related Ability to perform specific skills required to take part in various activities and sports 2 Health related Focused on areas that relate to our overall health status and our ability to perform daily tasks and activities Health related fitness 1 Cardiorespiratory fitness 2 Body composition 3 Musculoskeletal fitness Muscular strength Muscular endurance Flexibility Cardiorespiratory fitness CRF The ability of the body s circulatory heart blood vessels and respiratory systems lungs to supply fuel during sustained moderate to vigorous activities Often reflected and measured as oxygen consumption maximal submaximal These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute Oxygen consumption Rate of oxygen utilization during exercise Reflects The capacity of the cardiorespiratory system to transport oxygen to the working muscles The utilization of oxygen by the muscles during exercise Fick equation VO2 CO x A VO2 Cardiac output CO amount of blood leaving the heart per minute Arterial venous O2 difference A VO2 Difference in oxygen content between the arterial blood oxygen and the venous blood oxygen CO HR x SV Heart Rate HR of beats min Stroke Volume SV amount of blood heart pumps with each beat How to measure CRF Maximal O2 consumption VO2max Maximum capacity of the body to transport and use oxygen during exercise Measured directly or indirectly Direct maximal graded exercise test Indirect submaximal test field test Maximal graded exercise test Gold standard for measuring fitness Gradual increase in intensity to point of exhaustion Commonly conducted on a bike treadmill arm ergometer Hooked up to metabolic cart to analyze inspired expired air to determine oxygen consumption Peak When intensity increases oxygen consumption levels off Submaximal exercise tests Exercise at a moderate intensity and use equations to estimate VO 2max Equations use HR workload age sex Commonly use bike treadmill step test Key assumption Steady state HR at each exercise intensity Linear relationship between heart rate oxygen uptake and workload Field tests Measure time it takes to walk run specific distance Examples 9 12 minute run test 1 5 mile run walk beep test CRF and exercise training Exercise training results in More effecient oxygen delivery consumption Heart delivers oxygen rich blood more efficiently to the muscles Muscles use oxygen more efficiently VO2 CO x A VO2 Ability to sustain continuous aerobic activities What types of activities promote CRF Running biking swimming any type of aerobic activity CRF and aerobic exercise 15 increase in VO2max with training Strong genetic component to increase 75 Benefits of improved CRF Improved functioning and endurance Reduced risk for chronic diseases and death Body composition Relative amount of body fat vs lean body tissue fat free mass Fat Free Mass muscle bone water skin and blood Often expressed as percent body fat Measuring body composition Laboratory tests direct Hydrostatic weighing Air displacement plethysmography Bod Pod Dual energy X Ray absorptiometry DXA Field Methods indirect Skinfold method Bioelectrical impedance Use standard equations to calculate body composition based on measured values Field Methods indirect Anthropometric measures Waist circumference Body mass index BMI BMI kg m2 Waist to hip ratio Why is body composition important Unhealthy body composition associated with increased risk of disease Overweight Obesity CVD hypertension type 2 diabetes osteoarthritis certain cancers Underweight cystic fibrosis physiological dysfunction Body composition and exercise training Improved body composition profile Reduce percent body fat Increase fat free mass Improve bone mineral density Improve anthropometric measures Muscular fitness 3 Components Muscular Strength Muscular Endurance Flexibility Muscular fiber types Slow twitch red Smaller fibers Fatigue resistance Low force capacity Associated with endurance or aerobic activities Fast twitch white Larger fibers Fatigable High force capacity Capable of more powerful but shorter contractions The percent of fast twitch and slow twitch fibers largely genetically determined Most people roughly 50 50 Ratio not related to health but related to performance Muscle contraction Voluntary contraction controlled by Central Nervous System CNS Tension generated by muscles fibers Contraction can be static or dynamic Muscle may lengthen shorten or remain the same length Contraction types Static isometric contraction resistance is immovable muscle stays the same length while producing force Dynamic isotonic contraction visible joint movement Muscles are shortening or lengthening while producing force Eccentric muscle lengthens Concentric muscle shortens Muscular strength Ability of the muscles to develop maximal force How much we can lift push or pull in a single all out effort Power Amount of work performed in a given time Ability to exert strength and power limited by central nervous system CNS Factor influencing strength Muscle mass activated Type of fiber activated I vs II Number and sizeof motor units activated Motor unit single motor neuron and the muscle fibers it innervates Frequency at which action potentials are sent to muscle fibers Definitions related to strength Strength Training all types of exercise devoted to increasing muscular strength and size Hypertrophy Increase in muscle size as a result of training Result of increased volume of muscle fibers Atrophy Shrinking of the muscles Results from inactivity lack of use immobilization disease Strength assessment No single test to measure overall muscular strength or endurance needs to be specific to muscle group Static Often assessed using a dynamometer Can be upper or lower body Dynamic One repetition maximum 1 RM heaviest weight you can successfully lift one time without sacrificing form e g bench press leg press Safety concerns associated with maximal strength exertion Submaximal