Exercise Physiology Quiz

Key Terms

• Calorie: Energy measurement unit in biological systems.
• Ergometer: Exercise device for controlling and measuring physical work.
• Kilocalorie: Equivalent to 1,000 calories.
• Isometric: Muscle joint remains unchanged during contraction.
• Golgi Tendon Organ (GTO): Sensory receptor in muscle tendons that monitors tension.
• Concentric Retraction: Muscle contraction resulting in muscle shortening.
• Metabolism: All energy-producing and consuming processes within the body; the rate of energy use.
• Bioenergetics: Field studying metabolic processes.
• Hormones: Chemical substances produced or released by the body.
• Eccentric: Muscle contraction resulting in elongation or lengthening.
• Vo2 Max: Maximum oxygen consumption during peak exertion.
• Size Principle: Suggests motor neuron size determines order of motor unit recruitment.

Notable Figures

• Archibald V. Hill: Pioneer in energy metabolism and physiological studies on runners.
• Peter Karpovich: Introduced physiology into physical activity contexts.
• John Haldane: Developed methods for measuring oxygen during exercise.
• George Fitz: Headed anatomy, physiology, and physical training programs at Harvard.
• Thomas Cureton: Advocated for exercise as a means to improve health.
• Elsworth Buskirk: Founded Laboratory for Human Performance Research in 1974.
• Eric Hohwu-Christensen: Conducted multiple studies on carbohydrate and fat metabolism.
• Per-Olof Astrand: Researched physical fitness and endurance capabilities.
• Jonas Bergstrom: Revived the biopsy needle technique in 1966.
• John Holloszy/Charles Tipton: Advanced biochemical research on muscle metabolism.
• Phil Gollnick: Investigated muscle fiber characteristics.
• Birgitta Essén: Contributed to early studies on muscle fiber types in humans.
• Karen Piehl: Demonstrated selective recruitment of type I and II fibers.
• Barbara Drinkwater: Focused on issues related to female athletes.

Important Concepts

• Exercise Physiology: Examines bodily changes due to acute or chronic exercise.
• Homeostasis: State where cells, organs, and tissues maintain a stable internal environment.
• Aerobic Capacity Testing: Highest levels typically achieved on a treadmill.
• Cycle Ergometer: Effective for assessing cardiovascular measures compared to treadmills.
• Diurnal Rhythms: Patterns observed over a 24-hour period affecting bodily functions.

Muscle Fiber Insights

• Type II Fibers: Fast-twitch fibers specializing in quick, powerful bursts of activity.
• Recruitment Sequence: Type I, Type IIa, Type IIx fibers are recruited as exercise intensity rises.

Energy Production and Metabolism

• ATP Production: Carbohydrates serve as the primary energy source for short, intense activities.
• Fat Substrate: Yields the highest energy per gram but at a slower ATP production rate.
• Glycogen Depletion: Marathon runners commonly deplete glycogen around mile 20.
• Lactic Acid Accumulation: Major cause of fatigue during high-intensity exercise lasting 1-2 minutes.
• Fat and Carbohydrate Utilization: Rates depend on the intensity of the exercise performed.

Hormonal Regulation

• Hormonal Homeostasis: Achieved primarily through negative feedback mechanisms.
• ADH Function: Promotes water retention in response to dehydration.
• Aldosterone: Facilitates sodium retention, impacting fluid balance.
• Hunger Hormones: Ghrelin levels drop after high-intensity exercise.

Miscellaneous

• Major Trials: Cross-sectional studies analyze groups across different age ranges.
• Sodium Loss: Affects overall plasma volume and can lead to increased heart strain.

Extra Credit—Metabolic Process Overview

• Food intake is digested and broken down into macronutrients (carbohydrates, fats, proteins) which are then converted into energy (ATP) or stored as glycogen and fat for later use.