WEEK 3 - LEC 2 - Adaptations to cardiovascular training PDF

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Adaptations to cardiovascular training; general adaptation syndrome, seyles' model of adaptation, physiological variables in aerobic training, delivery of oxygen, muscle fiber types, etc....

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Adaptations to cardiovascular training Biking - alpine ski - swimming - running - tennis - what do they have in common? - All gave a solid cardiovascular conditioning base (intensive training sessions) - Many of these athletes can sustain very high intensity for a long period of time - Have high maximum steady state/pain threshold - Genetic ceiling - working @ their greatest potential (only marginal/small changes are able to be made as they are already so elite) - endurance/cardiovascular training has a bad reputation because people associate it with long/slow exercise when it comes to cardiovascular training (HOAX!) - Conditioning → anything greater than 2 mins, and has aerobic component - Cardiovascular fitness is the basis to build all other components of fitness Why is having a good cardiovascular fitness level important? - Basis of health (strong correlation with good cardiovascular health, VO2max, and risk of all cause mortality, metabolic syndrome, obesity, insulin resistance) - Improves tasks of everyday life - You are more efficient at delivering oxygen (physiological adaptation) - Perceive tasks as being less hard (psychological adaptation) - Important for recovery - More fit = less stress on body - Body recovers faster from activities/tasks of daily life Exercise imposes a massive stress to the body - Perturbs homeostasis - As humans, we are designed + created to adapt to stress (if we didn't adapt we would die at onset of life since we wouldn't be able to to handle breathing outside the womb) SAID principle Specific Adaptations to Imposed Demands - Your body responds to the stress placed on it. Stress dictates adaptation GAS Seyles’ model - explains short-term effects of exposure to stressors 1. Cellular army - cells that try to re-establish homeostasis when there is some kind of stressor/perturbation to homeostasis. Once exposed to

stress, the body is able to repair, and grow stronger so that when the body is exposed to the stressor again, the response will not be that bad 2. Body adapts to stressors (we are survivor driven). With repeated exposure our body adapts to it. 3. Too much stress is bad! There is an optimal amount of stress so we need to find that balance - example : DOMS - If we don't develop resistance or stressor is greater than our ability to adapt, we go into a decompensation phase. Can be bad and can lead to disease (body is in extreme stress for long period of time) - Stressor: event or occurrence, internal or external to the body, that disrupts homeostasis, forcing body to use its biological resources to resist, and adapt to the stress Seyles’ model of adaptation - how body respond to, and overcomes stress You need: a shock, recovery time (specificity dictates resistance!) - Sweet spot: for muscle growth + strength gain, is between alarm reaction and stage of resistance (without diverse training, can lead to exhaustion. Recall SAID principle. If you want to get fast, you have to train fast, train your body to get to that level.) - @ plateau, your body is ready for a new shock - If recovery does not happen, there will be a decrease in performance (enter stage of exhaustion) → leads to overreaching and overtraining syndrome (can be catastrophic to athlete) - Recovery time: 2mos → greater than a year Considerations for resistance phase of adaptation - Stressor; can leave body weak and depleted - More is not better = recovery time is pivotal - Poor nutritional choices can work opposite to what you want to accomplish - Internal + external factors can create greater stress - 80-90% of adaptations weight loss + gains in gym; happen from good nutrition! - Can make more gains by choosing proper diet than exercise alone Internal vs external factors Internal: sleep, nutrition, disease, sickness External: environment, pollution, allergies, altitude, heat, humidity

Defining endurance training In theory: 50-80% of VO2peak, 30-90 min/session, 5-7 days/week Prescription needs to be specific to the physical demands of the sport - All activities of daily life in sports teams/individual sports include endurance training - Make sure your training is specific to the demands of the sport, and that you don’t have this high volume of training the intensity What activities/occupations/sports are considered endurance? > what are the practical benefits of having a good aerobic base - Aerobic component is essential to all activities. - Conditioning is NOT exclusive to endurance to endurance sports. Conditioning is the most neglected from team-based sports but has HIGHEST transferability compared to strength training (to enhance performance) - All team sports have an aerobic component + endurance - Team based sports-although they are intermittent; and anaerobic; there is a very large aerobic component - When you improve cardiovascular fitness,this directly benefits ADL/sport Aerobic system is the foundation How much cardiovascular fitness one needs depends on the demands of the activity you are doing Recall gaps in training and how we want one to reach their end goal state from where they are. How they get from current to goal is the gap (need to develop aerobic system) Aerobic energy consumption = aerobic metabolism Anaerobic energy contribution ATP phosphocreatine + ATP stores Aerobic system is ALWAYS being used, it just depends on how energy is fractionated, depending on demand Limiting factors to endurance performance (limitations become adaptations!! - enhancement) 1. Delivery (cardiovascular system) - of O2 to the periphery and working muscles 2. Uptake (happen @ muscle level) - of the O2 @ contracting muscle 3. Utilization (happen @ muscle level) - of O2 for oxidative metabolism at the muscle

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CVS → more efficient = enhanced delivery Heart + vessels (arteries, arterioles, capillaries, venules, veins) help in delivering O2 to working muscle, and bringing that blood back to the heart More efficient as every contraction of the heart is better, resulting in more blood, and more O2 being delivered for a lower HR response 3 main ways to enhance delivery of oxygen 1. Stronger heart (when it gets stronger, the contraction ejects more blood) per contraction (increase in stroke volume). Increased size + increased contractility 2. Angiogenesis - creation of new capillaries/new vessels -helps in delivering more oxygen to working muscles → greater surface area to provide O2 to working muscles 3. Increased O2 carrying capacity by increasing RBC mass and hemoglobin mass

Delivery of oxygen O2 needs a taxi in the blood as it cannot freely move in the body itself. O2 is bound to protein hemoglobin Myoglobin takes up the O2 at skeletal muscle; in order to transport it to the electron transport chain where it is needed Doping- EPO (erythropoietin) stimulated bone marrow to increase the amount of RBC you have in body. If you have more RBC, you have more taxis available to deliver O2. with higher ability to deliver O2, you can increase the body’s ability to produce energy for energy metabolism, therefore improving endurance EPO is banned - unfair advantage, and is not safe - Because there are now so many RBC, blood is thicker so the heart has to pump harder, which could lead to heart attack (more viscous blood putting strain on heart) Uptake & use: recall skeletal muscle fiber types - Specificity of fiber type recruitment during endurance training - considerations for valid program design - You ALWAYS start by recruiting type 1 muscle fibers - If demand is higher, type 2a is recruited (more oxidative glycolytic) - If very high (sprint) you recruit type 1, type 2a, and 2b all together to make sure you meet demand for exercise - Muscle fiber recruitment is due to nerve impulse (motor unit recruitment @ NMJ) - *sweet spot* type 2a muscles - fast oxidative glycolytic - these muscle fibers can use oxygen and have fast glycolysis to produce energy quickly. They're less fatigue resistant - Exercise based sports have intervals → not just 1 speed.. Need to train the recruitment pattern. Sow, and fast to ensure you’re recruiting all types of fibers when fatigued.

High sustained intensity comes from fast oxidative glycolytic which requires greater muscle recruitment You really want to train type 2a muscle fiber type Depending on intensity of endurance training you do, it results in different recruitment of muscle fibers The predisposition for various activities based on fiber types are genetically determined Nature → can see possible conversions of fibre type based on training, however that difference is not significant. You can convert some types 2b to type 2a if doing more endurance based training Can convert type 1 to type 2 fibers if doing more intensive

Slow twitch is first, then you add layers of muscle fiber to generate the impulse and force you need to overcome the load Fiber type - genetics How much can you change → ~10% between or conversion with the type of training youre doing between fiber types - Genetics dictate what type of fiber you have - Some can convert but not all - Usain bolt → high amount of type 2b - Marathon runners → high amount of type 1 muscle fibers - Can have some interconversions between fibres within your genetic ceiling Fiber type conversion

Selective hypertrophy of type I fibers due to increased recruitment during aerobic activities (mostly because of increased number and size of mitochondria) ↓ Possible conversion of type 2b to type 2a → greater oxidative capacity and more similar characteristics to type I fibres = more fatigue resistant - If someone has more type 2b, you might want to do a higher amount of conditioning for this individual to push + interconvert fiber type to more type 2a (fast oxidative glycolytic and more fatigue resistant Uptake + use → skeletal muscle adaptations to endurance training (8 steps to enhance uptake and use of O2 within working muscle to ensure better adaptation to endurance training) Variable hypertrophy of type 1 and 2a fibers + conversion to be more oxidative - More mitochondria - can undergo krebs and ETC and not only focus on substrate level phosphorylation (occurs in cytoplasm outside mitochondria) - Enhanced uptake Increased myoglobin content - Muscle taxi myo (muscle) globin (globulin protein) - Is the oxygen taxi in muscle - Enhanced uptake Mitochondrial biogenesis - Enhanced utilization of O2 through oxidative metabolism Increased enzymes of aerobic metabolism (PSD, CS, etc) - Enhanced utilization of O2 through oxidative metabolism Reduced reliance on non-oxidative metabolism - Enhanced utilization of O2 through oxidative metabolism Increased storage of muscle glycogen - Enhanced utilization of O2 through oxidative metabolism - Last step of ETC requires O2; if we enhance ability to take up O2 into cell, we have more mitochondria in cell to use and will optimize energy production; therefore go longer with less fatigue Increased ability to uptake and utilize fatty acids - Enhanced utilization of O2 through oxidative metabolism Increased storage of IMTGs - Enhanced utilization of O2 through oxidative metabolism 3 adaptations that influence endurance and performance - Goal of endurance training - improve system tolerance and capacity (delivery, uptake, use) for the 3 performance/outcome variables 1. VO2max/peak - Max aerobic capacity - Max volume of oxygen you can take uup, deliver and use within a min

2. Metabolic efficiency - How efficient is your body at utilizing O2 for energy production 3. Gross metabolic efficiency - Cant directly assess internal changes, but we can assess external performance improvements - Ie Changes in VO2max, changes in metabolic efficiency to know how adaptations have translated into improved performance Maximum aerobic capacity (VO2max / VO2peak) - VO2peak/VO2max is strongly correlated to all-cause morbidity and CV fitness level - VO2peak increases 10-30% with aerobic training during first6 months of starting CV training/endurance Physiology drives performance change 1. High correlation of VO2max and Cardiac Output a. Increases strength of heart b. Greater delivery of oxygen 2. High correlation of VO2max and hemoglobin mass a. Increased ability to transport O2 b. Enhanced delivery of O2 to working muscle 3. moderate-high correlation of VO2max and blood volume a. Greater amount of blood volume Relationship between training intensity and improvement in VO2max Greatest improvement with VO2max occurs with high intensity training (HIIT) - can also see improvement in CVhealth - Can do intervals of high intensity, and then break - Greatest improvement in VO2max of ~33% occurs when training between 80-100% of VO2max - Lower intensity 50-70% of VO2max when trained at this level → good for elber where intervals are not preferred (slow but still making improvements) - Rate of return is affected depending on intensity that we prescribe Metabolic efficiency - lactate profile - How efficient are we in producing energy - ↑ mitochondria = can use more free fatty acids + we are more efficient at using glucose as an energy source because of krebs and ETC - As one becomes more endurance-trained, you increase speed of power with relatively same amount of blood lactate production post exercise

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Less glycolysis = less production of blood lactate as a result of exercise intensity - body is more efficient @ using glucose and free fatty acids as energy sources (less blood lactate being produced) Blood lactate profiling 1. Someone will sita at multiple different exercise intensities; getting harder 2. Take blood lactate sample from their fingertip]measure blood lactate 3. Measure blood lactate Gross mechanical efficiency - Adaptation to endurance training - How efficient are you? (determined through direct rate of fatigue, caloric expenditure, perceived effort, etc. - Definition: represents the link between cellular energy production and actual external performance (ie speed or power) - Only measured via use of direct or indirect calorimetry in conjunction with an output measurement (speed, velocity, power) - Varies significantly between individuals - disease, biomechanics (running, stride, gait), genetics, etc. - More efficient individual will be able to produce more power/velocity/for a lower metabolic rate (=less physiological strain) Factors affecting human efficiency Internal - Disease (affects oxygen take up) asthma COPD - Factors affecting VO2max - uptake delivery, and use of fO2 (if there are issues with mitochondria on genetic genetically, metabolism, enzyme activity, fuel storage, fatty acid level, intramuscular triglycerides) - Metabolism (enzyme activity, fuel storage) - Neuromuscular (propagation of nerve impulse)

External (Target to improve) - Aerodynamics (large gains when you improve aerodynamics) - Biomechanics - Equipment

Marginal gains *this is principle diminishing returns*

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2 places for biggest change 1. Lactate threshold (metabolism @ skeletal muscle level) 2. Critical power Marginal gains can be 1-2%

Lactate threshold/critical power + gross mechanical efficiency - Can be changed with endurance training in already champion level athletes As you because more fit and endurance trained, you will start to see diminishing returns in regards to training that you do (marginal gains) To see more change, you need to increase stress (large changes diminish, the better you get at something) Physiology drives adaptations - To train causes physiological stress to physiological system → drive the appropriate physiological adaptation - Changes in delivery, use and utilization with endurance training → improved VO2max/peak, metabolic efficiency, and gross mechanical efficiency - When assessing; want to check their response from VO2max standpoint or response to exercise to assess metabolic efficiency to see how this has changed over time - To assess gross mechanical efficiency - know the physiological changes that happened as a result of cardiovascular training If you dont use your muscles, you loose it - Up to a 50% reduction in mitochondrial mass after 1-2 weeks of de-training - Decrease in size of muscle due to decrease in density + volume of mitochondria - Too metabolically costly to maintain organelles that you aren't using (reduces ATP) Why is having a good aerobic fitness level important? (3 reasons)

1. Basis of health (cardiovascular metabolic health, body mass standpoint, lean body mass, prevention of metabolic disorders, tied to all-cause morbidity) 2. Improves tasks of everyday life - tasks more easier as you become more efficient in producing ATP (RPE is less) 3. Recovery between work shifts, sport shifts, sessions, set/reps are faster What are the common desired adaptations across populations? - We are trying to acquire the same physiological adaptations from cardiovascular training - As beginner, there will be a 10-30% improvement in first 3 months of being on cardiovascular training plan - For professional athletes; it is marginal gains (1-2%) and they need to be strategic on how to acquire changes. Need to stress the CVsystem in order to see improvement! Program design - one size does not fit all (no cookie cutter program allowed - Progression - regression Progress certain athletes/clients @ a faster rate Regress them by slowing them down, bring them to the basics and then progress them in the optimal pattern for that individual Goals of program design - Should be the center of your program design! 1. Injury prevention 2. Enhance ability to tolerate demands by developing a system capacity + structural tolerance 3. Enhance performance - Want to create a robust athlete (injury free, to be able to tolerate the demands of the sport well, with an enhancement in their performance The process prior to program design → KNOW THIS SHEET (best way to create a program) Physiological assessment - only for the assessment of physiology

1. Understanding the physical demands of the sport (demand/needs analysis) - What are the physical demands of the sport? Need to know this so you can be specific with your exercise prescription - Helps to ensure that training to impacting performance is optimized Sport demands analysis - questions to ask (first step - really understand the sport demands placed on the athlete) - What is the nature of the sport? collision/contact, cyclic/acyclic - What are the environmental conditions? Land, water, ice, air, wilderness, temperature, humidity, altitude - What are the physiological demands? - movement analysis (planes of motion), velocity of movements, duration of movements/length of competition, what does the year training plan look like - What are the common injuries? overuse/acute - Body composition considerations? - weight classes, body weight ratio, (fat:LBM) demands/needs analysis Determines demands of sport by assigning a degree of importance to the variables listed (key performance factor, important, moderately important, low importance, non applicable) Need to consider importance of each variable for both typical competition and athletes ability to sustain training load over several weeks/months KPF = quantifiable measure used to gauge performance success in the sport over time

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Should complete this BEFORE meeting with the individual. You get as much info as possible so that you can help athlete to best of ability + then carter a training program based on their needs From this chart, you determine whether this is a key performance factor to the sport and does it significantly impact performance (can determine main priority to work on based on their sport)

Know your athlete - detailed history - Develop a good rapport through discussion

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Note: previous injuries, personal goals, level of play, training age (in sport,with S+C experience), developmental age, trainability, other activities and sports, sport history (results, competitions, training, etc)

Trainability Is the faster adaptation to stimuli and the genetic endowment of athletes as they respond individually to specific stimuli and adapt to it accordingly Window of trainability: a critical period of development when training, has an optimal effect. Fast and large response! (varies per person)