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Chapter 11. Individual Differences and Measurement of Energy Capacities. Specificity. High O 2 max in one event doesn’t ensure a high O 2 max in another event. High Aerobic High Anaerobic Power High Anaerobic High Aerobic Power. Generality.
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Chapter 11 Individual Differences and Measurement of Energy Capacities McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Specificity • High O2max in one event doesn’t ensure a high O2max in another event. • High Aerobic High Anaerobic Power • High Anaerobic High Aerobic Power McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Generality • High aerobic power usually indicates above-average power in related activities. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Overview of Energy-Transfer Capacity During Exercise McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Anaerobic Energy Transfer: Evaluation of Immediate Energy Systems • Power tests: used to measure brief maximal capacity • Tests generally < 6 seconds • Power is calculated as Power = force × distance time McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Power Is Expressed in Watts 1 watt = 0.73756 ft-lbs · s-1 1 watt = 0.01433 kCal · min-1 1 watt = 0.0013 hp 1 watt = 6.12 kg · m · min-1 McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Stair Sprinting Power Tests • Time to sprint up 6 steps, 3 at a time, is determined Power = kg body wt × distance in meters time in seconds McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Jumping-Power Tests • Sergeant jump test • Low correlation with scores and actual ATP-PCr energy transfer • Standing broad jump McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Interrelationships Among Power Performance Tests • Power is highly task specific. • The usefulness of a test increases when it mimics sport performance. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Evaluation of Immediate Energy System: Physiologic Tests • Physiologic biochemical measures evaluate • Size of intramuscular ATP-PCr pool • Depletion rate of ATP and PCr in all-out short-duration exercise • O2 deficit calculated from initial phase of exercise O2 consumption curve • Alactic portion of recovery O2 consumption McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Evaluation of the Short-Term Energy System • After a few seconds of work, glycolysis generates increasingly more energy for ATP resynthesis. • As the rate of glycolysis increases, lactate accumulates. • Blood lactate levels provide the most common indicator of glycolytic activity. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Anaerobic Power Performance and Capacity Tests • Performances that substantially activate short-term energy systems require maximum exercise for up to 3 minutes. • Influences • Age • Skill • Gender • Motivation • Body size McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Tests that Most Closely Mimic the Sport’s Performance Are the Best! • Some good, commonly used tests include • Katch test • Wingate test • Both give measures of peak power and anaerobic capacity. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Gender Differences • Males generally score better than females. • Difference in gender occur even in children and adolescents despite corrections for lean body mass. • Evidence suggests a biologic difference in anaerobic exercise between genders. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Maximally Accumulated O2 Deficit • Determination of MAOD provides another indirect measure of anaerobic capacity. • MAOD is determined using the linear exercise intensity_O2 consumption relationship. • Data is collected from several submaximal treadmill trials. • Correlates positively with other tests McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Biologic Indicators for Anaerobic Power • Blood lactate levels • Glycogen depletion McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Individual Differences in Anaerobic Energy-Transfer Capacity • Factors contributing to differences include • Previous training • Capacity to buffer acid metabolites • Motivation McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Effects of Training • Anaerobically trained individuals have • Greater lactate-generating capabilities • Greater depletion of muscle glycogen McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Buffering of Acid Metabolites • Training fails to increase alkaline reserve. • Ingestion of sodium bicarbonate may increase buffering capacity and improve performance. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Motivation • Individuals willing to tolerate pain or exhibit mental toughness are able to generate more lactate and experience greater glycogen depletion. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Aerobic Energy: The Long-Term Energy System • Maximal oxygen capacity plays a large role in determining endurance performance. • Attaining a high O2max requires integration of pulmonary, CV, and neuromuscular function. • O2 max is a fundamental measure of physiologic functional capacity for exercise. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Assessment of Maximal O2 Consumption • Considerable research has been done to develop standardized tests to assess aerobic power and provide norms related to • Age • Gender • Body size • Training state McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Criteria for Maximal O2 Consumption • A leveling off in O2 consumption despite an increase in exercise intensity generally assures O2max has been reached. • Controversy regarding precise criteria remains. • O2peak = highest value of oxygen consumption measured during graded test exercise McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Maximal O2 Consumption Tests • O2max is determined using exercise that activate the body’s large muscle groups • Treadmill • Bench stepping • Stationary cycling • Test usually consists of graded exercise with much prodding to reach O2max or O2peak. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Test Comparisons • Two popular protocols are available. • Continuous • Discontinuous McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Factors that Affect Max O2 Consumption • Mode of exercise • Heredity • State of training • Gender • Body size and composition • Age McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Mode of Exercise • Influences muscle mass activated • Treadmill usually > cycling • Bench stepping similar to treadmill scores • Arm cranking only ~ 70% treadmill values • Specificity and skill are very influential in many modes. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Heredity • Most physical fitness characteristics demonstrate high heritability. • Research shows that up to 93% of difference in O2max is due to heredity. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
State of Training • 5 − 20% variation in scores seen as fitness levels of individuals changed at time of testing McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Gender • Women achieve scores on average 15 − 30% lower than men. • Differences may be due to 1. Muscle mass 2. Hemoglobin concentration • Considerable variability exists; many women score higher than the average man. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Body Size and Composition • Body size creates large differences. • Common practice: Express O2max relative to body mass • Controversy exists about various methods of adjusting scores to normalcy for gender differences • Adjustments made by each factor gives different results. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Age • O2max declines after age 25 by ~ 1% per year. • Age also influences O2max values in boys and girls. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Aerobic Capacity Prediction Tests • Submaximal tests are used to • Decrease cost • Decrease time • Decrease risk McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
A Word of Caution about Predictions • All prediction tests contain an error known as the standard error of estimate (SEE). • SEE is expressed in measurement units used for prediction or as a percentage. • Sometimes the SEE can be large. • At times, the SEE is small, and the test is more useful. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Prediction Tests Commonly Used • Walking tests • Endurance runs • Step tests McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Predictions Based on Heart Rate • Use exercise or postexercise heart rate and a standardized exercise regimen • Apply linear relationship between heart rate and O2 consumption • Data are gathered at several workloads. • A line or “best fit” is extended through predicted maximum heart rate. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Assumptions Required for HR Predictions • Linearity of HR – O2 consumption through all exercise intensities • Similar maximum HR for all subjects • Constant economy and mechanical efficiency throughout exercise • Limited daily variations in HR (usually 5 beats/min-1) McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
The Step Test • Practical test that uses HR during recovery • Prediction equations applied to test results estimate O2max with reasonable accuracy. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Predictions from Nonexercise Data • Data used • Gender • BMI • Physical activity rating (PAR) • 0 − 10 over 6 months • Perceived functional ability (PFA) McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition
Predictions from Nonexercise Data • Regression equations are then used to calculate scores. McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition