KIN 2210: Lecture 3 - Aerobic Performance PDF

KIN 2210: Advanced Exercise Prescription Aerobic Performance Required Reading Course Notes Reading  Agenda Physiological Basis of aerobic performance Adaptations to Training Training Methods Program Design Physiological Basis of Aerob...

KIN 2210: Advanced Exercise Prescription Aerobic Performance Required Reading Course Notes Reading  Agenda Physiological Basis of aerobic performance Adaptations to Training Training Methods Program Design Physiological Basis of Aerobic Performance  Cardiorespiratory Fitness The ability to perform dynamic exercise involving large muscle groups at moderate-to- high intensity for prolonged periods (ACSM, 2014)  Cardiorespiratory System Source: Marieb, E. (2010). Human Anatomy and Physiology. Benjamin Cummings.  Function of Cardiorespiratory System 1 2 4 1. Ventilation External Respiration Internal Respiration 2. External Respiration 3 3. Transport of O2 and CO2 4. Internal Respiration Maximum Oxygen Uptake (VO2max) Maximum amount of oxygen the body can use per minute of physical activity Extract O2 Deliver O2 Utilize O2  %VO2max sustained Maximum Oxygen Uptake (VO2max) during race Extract O2 Deliver O2 Utilize O2 Determinants of Endurance Performance Sets upper limit of How much of the aerobic performance engine can you use before you start Ie. Size of accumulating fatigue physiological engine inducing by-products Ability to convert Race energy into mechanical Velocity work Basset and Howley, 2000  VO2max Pulmonary System Cardiac Output Oxygen Carrying Capacity of the Blood  Pulmonary System Gas exchange with external environment, ensuring O2 reaches bloodstream Bronchiole Alveolus Pulmonary Pulmonary Healthy lungs maintain Artery Vein SPO2 > 95% at rest and during maximal intensity exercise for most people Pulmonary Capillary Erythrocyte (Red Blood Cell)  … during exercise Transit time decreases during exercise 125 Time required to reach equilibrium 100 PO2 (mmHg) Resting 75 Untrained Peak Ex. Endurance trained 50 Peak Ex. 25 0 0.00 0.25 0.50 0.75 Time in Pulmonary Capillaries (s)  Cardiac Output Volume of blood pumped by the heart per minute Number of times heart beats every minute Volume of blood ejected by each ventricle every beat Volume of blood ejected by heart every minute  … during exercise Heart rate, Stroke Volume, Cardiac Output increase with increasing exercise intensities  Training Adaptations ↑SV à ↑Q à ↑ O2 Transport Increase No Change Increase Increase Murias et al (2010) Time course and mechanisms of adaptations in cardiorespiratory fitness with endurance training in older and young men. J Appl Physiol 108: 621–627  Oxygen Carrying Capacity Red Blood Cell Oxygen Dissociation Curve Hemoglobin releases O2 when O2 availability is low Alveoli Muscle Cell  … during exercise Hemoglobin dissociation curve shifts to the right, making more oxygen available Resting Exercise Right ward shift mediated by: ↓ pH ↑ Temperature ↑ CO2  Training Adaptation ↑RBC à ↑Hb à ↑ O2 Transport Increase Red Blood Cell Volume (ml) Montero et al. (2017) Erythropoiesis with endurance training: dynamics and mechanisms. Am J Physiol Regul Integr Comp Physiol 312: R894 –R902  %VO2max at LT Muscle Capillary Density Mitochondrial Density Fiber Type Distribution  Muscle Capillaries Gas exchange with internal environment, ensuring O2 reaches muscle fibers  … during exercise For the same volume flow of blood, transit time through capillary bed is elongated At rest, some capillaries have little to no blood flow. During strenuous exercise, all capillaries are open  Training Adaptations ↑ Capillary:Fiber à ↑ O2 Extraction Murias et al. (2011) Adaptations in Capillarization and Citrate Synthase Activity in Response to Endurance Training in Older and Young Men. J Gerontol A Biol Sci Med Sci. 66A(9):957–964  Mitochondria Use O2 to produce ATP during aerobic metabolism  Training Adaptations ↑ Mitochondrial Volume à ↑ O2 utilization Hoppeler et al (1985) Endurance training in humans: aerobic capacity and structure of skeletal muscle. J. Appl. Physiol. 59(2):320-327  Muscle Fiber Type Distribution Muscle fibers are classified into two main types: Type I (slow-twitch) and Type II (fast-twitch) Type I Type II Specialized for endurance Type IIa fibers have activities intermediate properties, High mitochondrial density supporting both endurance and strength. Type IIx fibers generate rapid, powerful contractions but fatigue quickly.  Training Adaptations Type I ß Type II ↑ 12% ↓ 24% Howald et al (1985) Influences of endurance training on the ultrastructural composition of the different muscle fiber types in humans. Pflugers Arch 403: 369–376  Training Adaptation Summary Endurance Training leads to ↑ Cardiac Output ↑ O2 ↑ RBC & Hemoglobin } Delivery } ↑ Capillary Density ↑ Capillary:Fiber ↑ O2 Utilization ↑ Type I ß Type II ↑ Mitochondrial Density Training Methods  Long, Slow Distance LSD training involves prolonged, steady-state exercise performed at a moderate to low intensity. Often used to improve aerobic performance by enhancing the body’s ability to efficiently use oxygen over extended periods.  Threshold Training Threshold training focuses on exercising at or near the lactate threshold (the point where lactate begins to accumulate in the blood faster than it can be cleared). Often used to improve aerobic performance by increasing lactate tolerance and clearance.  High-Intensity Interval Training HIIT consists of repeated short bouts of high- intensity exercise alternated with periods of low-intensity recovery or rest. Often used to improve aerobic performance by enhancing the body’s ability to deliver oxygen to the tissues. Program Design Variables  Summary Table Goal Volume Frequency Duration Intensity Work:Rest (min/week) (x/week) (minutes) Repetitions (%VO2max) Ratio Long, Slow High 3-5 50 - 90 1 50 - 70% - Distance (>250min) Threshold Moderate 3-4 25 – 45 1 75 – 85% - Training (100 – 150 min) High-Intensity Low 3 3–5 5 - 12 85 – 100% 1:0.5 - 1:1 Intervals (75 – 100 min)  Effect of Exercise Selection Reference Training Fiber Size Howald et al, 1985 Cycling No change (Diameter) Hoppeler et al, 1985 Cycling No change (CSA) Trappe et al, 2006 Running Decreased (Diameter) A smaller fiber diameter decreases the diffusion distance for oxygen and substrates Differential adaptations to cycling and running  Effect of Training Frequency More frequent sessions led to more adaptions Mpampoulis, et al. (2024). Effect of Different Reduced Training Frequencies after 12 Weeks of Concurrent Resistance and Aerobic Training on Muscle Strength and Morphology. Sports, 12(7), 198  Example Weekly Plan Long Slow Distance Mon Tues Wed Thurs Fri Sat Sun LSD Rest LSD Rest LSD Rest Rest 90 min 90 min 90 min Intervals LSD Rest LT Rest LSD Rest 5 x 5 min 90 min 30 min 90 min  Example Weekly Plan Threshold Training Mon Tues Wed Thurs Fri Sat Sun LT Rest LT Rest LT Rest Rest 35 min 35 min 35 min LT Intervals Rest LT Rest LSD Rest 35 min 5 x 5 min 35 min 45 min  Example Weekly Plan High-Intensity Interval Training Mon Tues Wed Thurs Fri Sat Sun HIIT Rest HIIT Rest HIIT Rest Rest 5 x 5 min 5 x 5 min 5 x 5 min HITT LT Rest HIIT Rest LSD Rest 5 x 5 min 20 min 5 x 5 min 60 min  Exercise Order Warm up: 5 – 10 min Conditioning: TBD Cool Down: 5 – 10 min Stretching: 10 min  Effect of Training Intensity Physiological adaptations are linked to the intensity performed Gormley et al (2008). Effect of Intensity of Aerobic Training on V˙O2max. Medicine & Science in Sports & Exercise 40(7):p 1336-1343  Practical Implications Traditional thinking is … HIIT à Increases VO2max Threshold Training à Improves LT LSD à Enhances fat metabolism The relative importance of the intensity, duration and frequency of training is being reexamined for many key physiological adaptations to exercise. Calculating Exercise Intensity  Progression of Training Goal Duration Frequency Repetitions Intensity #1 #2 #3 Long, Slow Add 5 min/session/week Progressively increase 1-2 %/week - Distance until desired duration is number of sessions/week achieved from 3 to 5 days #1 #2 #3 Threshold Add 5 min/session/week Increase number of 1-2 %/week - Training until desired duration is sessions/week from 3 to 4 achieved days #1 #2 #3 Add 15-30 s/interval/week Add 1 interval/session 1-2 %/week High-Intensity Intervals until desired duration is every 2 weeks achieved * Rate of progression will depend on many factors such as health, age, training status  Lab 3 Jan 27/28 Continuous vs Interval Training Bring your HR monitors  Next Class … Anaerobic Performance