Elite Aerobic Athlete
Chronic Adaptations to Kim Crow
Kim Crow - Rower
Kim Crow was born on August 9th in 1985, she is an Australian world Champion and Olympic medal winning rower. Prior to 2005 Crow was a 400m hurdler but due to a bad injury in her foot she had to stop running. She was then talent ID into rower because of her height of 188cm. She started rowing in 2005 and competed at The Australian Nationals in the pair with Phoebe Stanley were they won. She then trailed for the Australian senior A team were she made the Women’s eight were they came third at worlds. She then rowed in a pair with Sarah Cook from 2008 when they competed at Beijing Olympics. She then moved to row in the single scull in order to be more competitive at the Olympics. In the London Olympics in 2012 Crow competed in two events, the women’s single scull and double scull, were she won bronze in the single and silver in the double. In the 2013 World Rowing Championships Crow won gold in the single scull. Crow has been base in Canberra at the AIS from 2009 on wards.
Interval Training (long / medium interval)
Interval training is were high intensities are alternated with rest periods. The length of the work and rest periods determines what energy systems is been developed. Interval training can target specific energy systems, for rowing it is important to train the aerobic energy system therefor long interval specifically trains this. Lactate tolerance can be developed in medium-interval, which is crucial rowing due to the length of a race (2000m). Long interval training is where the work period uses the aerobic system. The aerobic system is dominant when the work period is one minute or longer or the work to rest ratio is 1:1 or greater. The aim of long interval training is to increase the athletes Lactate inflection point (LIP), this is important for rowing because in a race the athlete must perform just under maximal effort in order to sustain for a whole race. Therefor with an increased LIP athletes are able to perform at a higher ability for longer.
Continuous training involves performing an activity nonstop for a period of time longer than 20 minutes. In the training method the athlete should maintain a heart rate between 70-85% of max HR, this is the aerobic training zone. This training method is very important for rowing because the dominant energy system in a rowing race is the aerobic system, therefor training in this energy system will enable specific improvements to be faster in a race. To improve in this area Crow will have to train this method 3-4 times a week in order for the body to make adaptations and improve her aerobic energy system.
Chronic Adaptations to Continuous Aerobic Training
Chronic adaptations improve the efficiency of the aerobic energy system to provide energy to the working muscles
Increased capillarisation that feed the heart, aerobic training increase the amount of capillaries that lead to the heart and surround muscle fibers, this allows for better blood flow to the heart so the more oxygen can be delivered to the myocardium.
Increased size of the left ventricle cavity of the heart, this is because the heart is a muscle therefor it adapts to training by becoming bigger and stronger. This will occur after a twelve month training program because this length of training enables enough time for the muscle to grow.
Increased stroke volume occurs due to the increase in size of the left ventricle, and lowered resting heart rate provides more time for the ventricles to fill up between contractions.
Decreased resting heart rate and decreased heart rate during sub-max efforts, this is because of the increased size of the heart. This results in the heat no having to work as hard to provide the required oxygen and nutrients to the muscles
Increased cardiac output at maximal workloads, this increases the delivery of oxygen and allows greater aerobic glycolysis to occur
Decreased recovery time, less time will be taken for the body to turn to resting levels following exercise
Increased blood flow away from organs and working muscles, this is because the muscles are more efficient in using oxygen after aerobic training therefor the muscles require less blood and that extra blood then flows away from the working muscles and organs
Increased in plasma volume and red blood cell volume, therefor increased overall blood volume. Highly training athletes have a higher blood volume due to the positive effects that it brings, it assists in increasing stroke volume and regulation of body temperate
Increased hemoglobin levels, haemoglobin is important for the transportation of oxygen around the body, increased blood volume is associated with greater amounts of haemoglobin
Decreased blood lactate concentration, aerobic training helps athletes to become better at clearing lactate from the blood. This is because aerobically trained athletes have increased oxidization and gluconeogenesis, this increases the lactate inflection point (LIP) so that athletes are able to work at higher intensities before reaching LIP
Decreased blood pressure, this occurs as a cardio protective effect
Increased lung ventilation during max workloads, because of the increased size of the lungs ventilation can increase at max intensities making it more accessible to get lots of oxygen faster than untrained athletes
Increased vo2 max, this is due to an increase in oxygen delivery to the working muscles and an increase in the ability of the muscles to extract the oxygen from the blood
Increased tidal volume, Tidal volume (TV) increases after aerobic training at maximal levels, this means more oxygen can be extracted from the air in one breath.
Decreased respiratory rate, at resting and sub-maximal levels repertory rate decreases because lung function has improved and more oxygen can be extracted from one breath—meaning the athlete does not have to breathe as frequently.
Increased diffusion, greater alveolar-capillary surface area increases diffusion, diffusion of oxygen across the alveolar-capillary membrane and carbon dioxide across the tissue capillary membrane is greater in trained athletes.
Increased alveolar-capillary surface area, due to an increase in lung volume this provides greater alveolar-capillary surface area and more sites when diffusion can occur.
Decreased ventilation at rest and sub max exercise, this is because trained athletes are better at using the oxygen supplied therefor don’t need as much oxygen at rest and sub max intensities.
Increased lung and vital capacity, total lung capacity id the amount of air in the lungs at the end of a maximal inspiration, vital volume is the air that can be forceful expired after maximal inspiration, this is from a structural change in the lung because they increase in size from aerobic training
Increased oxidative enzymes, this is due to the increase in mitochondria numbers that allows more ATP to be made and make oxidative enzymes increase
Increased oxygen utilization, aerobic training enables to body to increase the attraction of oxygen to the muscles cells, then use the oxygen to make ATP therefor the muscles can create more contractions through the oxygen utilization, this is from increased mitochondria and myoglobin stores
Increased myoglobin concentration, aerobic training induces a structural change to the slow twitch muscles to increase myoglobin stores, this increases the muscles ability to extract oxygen and deliver it to the mitochondria for the production of ATP
Increased mitochondria number, size and surface area, through aerobic training the body undergoes structural training to the muscles, increase mitochondria number, size and surface are is a structural adaption to training, this enables better oxygen utilization
Increased oxidation of glucose and fats, the increase of the muscle capacity allows an increase of oxidation of glucose and fats, this means that an athlete can rely less on glycogen and uses fats, sparing they glycogen stores and increasing their ability to work for longer
Increased a-vo2 difference, aerobic training increases the amount of oxygen that can be extracts from the blood to the muscles, this increases the diffusion of oxygen and carbon dioxide. This combined with the increased capacity of the muscle to extract and process oxygen a-vo2 difference therefor increases
Increased size of slow twitch muscles, this is due to the increased capillarisation of the fibers that increases the size of the muscle
Chronic Adaptations Leading to Improved Performances
Decreased blood lactate concentration
A rowing race dominate energy system is the aerobic energy system. In order to train for this race Kim Crow conducts aerobic training methods, such methods decrease the body’s blood lactate concentration. Through aerobic training oxidization, gluconeogenesis and glycolytic enzymes all improve, this improves the body’s ability to produce glucose from amino acids, fats and lactate within the liver therefor decreasing blood lactate concentration. A decreased blood lactate concentration results in an improvement to the lactate inflection point (LIP), the point at with the body can no longer clear lactic acid at the same rate as it is produced. The hydrogen ions in lactic acid build up with in the muscles after LIP, this affects the ph levels around the muscle creating a more acidic surrounding for the enzymes, this reduces there contraction rate making the athlete slow down. Kim Crow through aerobic training has an increased LIP and therefor decreasing the blood lactate concentration. This mean during a race her body will be able to clear lactic acid for a longer period of time through her increased LIP. Meaning that she will be able to perform at a high level of intensity for a longer period of time as she will not be affected by a buildup of lactic acid, and therefor can go faster.
Increased size of the left ventricle cavity of the heart,
Kim Crow through her aerobic training program will have an increased left ventricle cavity of the heart. This is a structural adaption to training, because of hypertrophy and the heart being a muscle therefor it adapts to training by becoming bigger and stronger. Due to the increase in heart size this then increases the capacity of the heart, increasing stroke volume and decreasing heart rate. The heart is able to pump more blood in one contraction therefor the heart doesn't need to contract as frequently, decreasing heart rate. Having a lower heart rate therefor means that at sub-maximal intensities heart rate will also be lower, and at high intensities will be able to sustain the intensity for longer. In Crows rowing race this means that she can perform at her highest aerobic intensity for longer, reducing the amount of time in the anaerobic system, reducing by-products. Crow will be able to clear by-products for longer due to the increased oxygen intake through increased heart ventricle capacity. During Crows race she can maintain a high intensity for longer and resist by-products for longer making her be able to row faster for longer.
Increased mitochondria number, size and surface area
Through aerobic training the muscles undergo adaptations increasing the number, size and surface area of the mitochondria within the cells. Kim Crow will have these adaptations to her mitochondria through her aerobic training, increasing her performance. The mitochondria are the sites at which ATP is resynthesized and glycogen and triglycerides stores are oxidized. The more mitochondria and size of them results in an increased oxidization of fuels producing ATP. Crow having more mitochondria and larger mitochondria enables her to get more ATP and energy to the working muscle and cells. Having an increased amount of mitochondria mean that during a race Crow is able to access more energy and ATP for her working muscle enabling her to work at high intensities for longer, allowing her to race faster.
Increased myoglobin concentration
Myoglobin is a protein found in the muscles and is the primary oxygen carrying pigment of the muscles. High concentrations of myoglobin increases the muscles ability to extract oxygen and deliver it to the mitochondria for the production of ATP in muscle cells. Having high concentrations of myoglobin allow athletes to hold their breath for a longer period of time. Crow having a higher concentration of myoglobin means that she does not need as much oxygen because the oxygen she does have will be more efficiently used. Her muscle cells will have access to more oxygen then an untrained athlete allowing her to create more ATP. Having the ability to create more ATP and use her oxygen more efficiently means that her can stay at higher intensities and have less effect on her body, enabling Crow to stay at that high intensity for longer and therefor rowing faster.
Increased lung ventilation during max workloads
Crow will have an increased lung size due to her aerobic training, this enables her ventilation to increase during max workloads. Ventilation is the movement of air between the environment and the lungs via inhalation and exhalation and the exchange of oxygen and carbon dioxide. Having a higher ventilation will enable Crow to have more oxygen the flow to the working muscles and mitochondria to create ATP. This allows Crow to have more energy and oxygen to work at higher intensities for longer.
Increased lung and vital capacity
An increase in lung and vital capacity occurs through aerobic training as a structural adaptation, Crow would have these adaptions due to her training for rowing. Total lung capacity is the amount of air in the lungs at the end of a maximal inspiration, vital volume is the air that can be forceful expired after maximal inspiration. Having an increases lung capacity enables more oxygen to be up taken in one breath meaning more oxygen for less work compared to an untrained athlete. Having more oxygen means that Crow will have more ATP made in the mitochondria enabling to have more energy and oxygen going to the working muscles and cells. Having these adaptations Crow will be able to work at high intensities for longer and have a more economical resynthesize of ATP.
American Physiological Society Research Paper - Exercise training increases mitochondrial biogenesis in the brain conducted on mice - Published 1 October 2011 – by Jennifer L. Steiner , E. Angela Murphy, Jamie L. McClellan , Martin D. Carmichael , J. Mark Davis Journal of Applied Physiology
AIS- facts sheets- Sports nutrition http://www.ausport.gov.au/ais/nutrition/factsheets/basics/carbohydrate__how_much
Rowing Australia - Interview with Chris O’Brien (National High Performance Director) on the 7th of August 2014 in Hamburg Germany in regards to Kim Crows training program and fitness testing, pre and post Olympic test and adaptations from training
Class Notes - Ms Bower’s class notes handed out to the class, Chronic Adaptations PowerPoint notes
Sports Fitness Advisor – created by Sporting Excellence Ltd. - http://www.sport-fitness-advisor.com/lactate-threshold.html