Energy Systems
ATP/PC | Lactic Acid (anaerobic glycolysis) | Aerobic (aerobic glycolysis) | |
Fuel source | ATP | Blood glucose Muscle glycogen | Glucose, fatty acids |
Efficiency of ATP production | Very fast, limited store | Very efficient | Slower and longer = more ATP |
System duration | 8-12 seconds | Short, high intensity 1-3min | 2mins-hrs (mainly endurance) |
Causes of fatigue | Depletion of fuel | Reaching lactic threshold | Depletion of glucose to working muscles |
By-products | Heat (Standard) | Pyruvic acid (lactate and hydrogen ions) | Carbon dioxide, water |
Process and rate of recovery | Recovers as creatine connects to free phosphate 30sec-2min | 20min-2hr | Higher intensity = longer recovery |
Types of Training and Training Methods
Aerobic Training
Specifically targets the aerobic energy system and cardiovascular system. Should be done 3 times a week at between 70%-80% MHR for >30 min. Affects performance by increasing the delivery of oxygen to the muscles, improving removal of waste and enhancing muscles ability to use aerobic energy systems.
Continuous training
When the athlete performs the same activity at the same intensity for a specified duration of time. E.g. running. Best suited for sports where intensity does not change. Long, slow distance training is standard for those who need to improve general condition. High Intensity, moderate duration is better for more advanced athletes.
Fartlek Training
Participants vary speed and terrain, thereby using different energy systems. E.g. running on sand and road.
Interval Training
Involves alternating sessions of work and recovery, develops both anaerobic and aerobic systems. The level of intensity is related to work interval, if intensity is 100%, work interval is shorter. Involves intensity, time, reps and work rest ratio. WR ratio is generally 1:3.
Circuit training
Involves various activities normally done for a set time. Intensity can vary or stay the same and can be used for multiple types of training. For it to be aerobic, it must focus on aerobic activities.
Aerobics
Performed to music, involves flexibility, strength e.g. Zumba
Anaerobic Training
The use of two anaerobic pathways as the major supply of energy. Activity must have high intensity (generally heart rate >85%). Short intervals are effective use of training. One of the most effective ways to train is the use of short intervals.
In anaerobic training, intervals generally range from between 10 sec to 2 min, with the workload being high (80-90%), with a work rest ratio of 1:3. The rest component may be just sitting or may involve gentle work e.g. walking. The intervals are sets or reps designed to overload the system.
Reps lasting for 10 sec or less are designed to improve the ATP-PC stores in the muscles. Slightly longer efforts (up to 2 min) aim to improve the body’s tolerance to pyruvic acid.
Anaerobic training involves a single activity with specified changes in intensity at specified times. It is usually shorter periods of time at high intensity.it is best suited for sports that require frequent, high intensity bursts, with some rest in-between.
Other examples of anaerobic training includes resistance training and plyometrics.
Flexibility Training
Muscles require length. This can be enhanced through sound flexibility training. Flexibility training is essential for:
- Prevention of injury
- Improved coordination between muscle groups
- Muscular relaxation
- Decreasing soreness following exercise
- Increased range of movement
Flexibility is affected by factors such as age, sex, temperature and specificity
Flexibility training aims to increase a joint’s range of movement (ROM). There is active and passive ROM. Active ROM is Rom produced by an athlete by contracting their muscles, whilst passive is ROM produced by external force. Generally, active Rom affects performance, though passive ROM stretches can be used to increase active ROM.
Three common types of stretching are:
- Static
- Dynamic (ballistic and proprioceptive neuromuscular facilitation (PNF))
During static stretching the muscle is slowly stretched to a point/position which is held for approx. 30 sec. It is safe and often used in rehab.
Ballistic stretching involves repeated movements such as swinging and bouncing to gain extra stretch. Activates a mechanism called stretch flex, causing the muscle to contract. The force and momentum can be potentially harmful. It should only be used by advanced athletes following a thorough warm up. The movement should be executed rhythmically.
PNF stretching involves a static stretch followed by a contraction until the stretch is no longer felt, then a further lengthening of the muscle to hold another static stretch.
Strength Training
Fundamental to improve in most sports. 3 programs:
- Isotonic programs
- Isometric programs
- Isokinetic programs
Strength gains will only be made when the program is exercise specific, employs the overload principle, uses progressive resistance (resistance is increased as adaptation occurs).
There are 4 types of strength:
- Absolute (maximum force)
- Relative (strength generated relative to one’s weight)
- Strength endurance
- Power
Strength training involves reps, Reps maximum, set, resistance and rest.
Strength training affects performance by causing muscular hypertrophy (growth in myocyte cross sectional area). It causes stress on the muscle, causing minor tears. The body responds to the stress by repairing the tears and increasing the size of the muscle so it can adequately deal with the stress should it happen again.
Principles of Training
The principles of training help when selecting correct training type and method in order to help improve performance. The principles of training are:
- Progressive overload
- Specificity
- Reversibility
- Variety
- Training thresholds
- Warm up and cool down techniques
Overload
When you train or exercise, your cells are being damaged and resources being used up. This is why you generally feel weaker after exercise. How weak you feel depends on the intensity and duration of the exercise. The basic principle of progressive overload is that a training effect is produced when the system or tissue is worked harder than the accustomed to. As the body adapts to new levels, training should continue to be increased. The principle implies that adaptations will only occur when the training load is greater than normal and is progressively increased as improvements occur. These adaptations will not occur if the load or resistance is too great or small. These adaptations can only occur if the body has enough time to recover.
Some examples of applications regarding overload are:
- Aerobic training reflects overload in regards to the heart’s ability to pump out more blood to the working muscles.
- Strength training applies the overload principle which results in increased cross sectional area of the muscle, called muscular hypertrophy.
- Flexibility training uses the overload principle which results in the muscle being able to stretch further.
Specificity
States that the type of exercise being used in training should be specific to:
- Task requirements
- Energy systems
- Muscle groups required in the task
- Components of fitness involved
The specificity principle implies that the effects of a training program will be specifically related to the manner in which the program is conducted. It focuses on what is being performed at training and its similarity to what happens when the athlete is competing. Since the body adapts to stress in very specific ways, it should be as realistic as competition scenarios as possible.
Energy system/s most appropriate to the activity should be a focus in related training procedures. This is called metabolic specificity.
The principle of specificity when applied to muscle groups suggests that those groups used for the activity needs to be the same as the groups used during training. This is because the body ‘recruits’ the type of muscle fibres that are best able to do the task. E.g. white fast twitch fibres for anaerobic, red slow twitch for aerobic.
Components of fitness developed during training should closely resemble those used in a game scenario. E.g. strength, flexibility, agility, etc.
There is a place for cross training (training not designed for an athlete’s specific sport), it can be used as a supplement to regular training. Cross training can help with:
- Motivation
- Maintenance
- Avoiding/recovering from injury
- Assisting with muscular balance
Reversibility
Effects of training are reversible. This means if a person stops (or fails to exercise at the right intensity) the training effects will be lost. After only one to two weeks of stopping training, significant physiological reductions can occur. Many athletes employ maintenance programs during the off season in order to combat reversibility.
Anaerobic training is quickly reversed.
Aerobic training is moderately reversed.
Flexibility training is extremely slowly reversed.
Variety
To become proficient at most sports, athletes must train for many hours. This training can often become boring and repetitive, especially if it is for endurance type sports. Whilst variety is not necessary, it helps with morale and motivation.
Training programs should take into account an athlete’s fitness, interests, needs, skills etc.
Applications of this principle include:
- Aerobic (swimming, running, cycling etc.)
- Strength (isometric, isotonic, isokinetic all increase strength but do so in different methods)
- Flexibility (static, dynamic, PNF)
Training Thresholds
Generally refers to the specific point that, when passed, take the person to a new level. When we train we expect a physical improvement to occur. However, for this improvement to occur, an athlete must work at a level of intensity that will cause their body to respond in a particular way. The magnitude of improvement is approx. proportional to the threshold at which they work.
The lower level at which we can work and still make some fitness gains is called the aerobic threshold. It refers to a level of intensity that is sufficient to cause a training effect, and is approx. 70% MHR.
When a person is working above the aerobic training threshold but below the anaerobic threshold they are working in what is called the aerobic training zone. This zone refers to a level of intensity that causes the heart to rise high enough to make significant training gains.
The uppermost level is called the anaerobic threshold or the lactate inflection point (LIP), a point in which further effort is characterised by fatigue. The LIP reflects the balance between lactate entry and removal from the blood. If exercise intensity increases after the LIP is reached, blood lactate concentration will substantially increase. The anaerobic threshold refers to the level of intensity in physical activity where the accumulation of lactic acid in the blood increases very quickly.
Working between the aerobic and anaerobic thresholds is necessary for fitness gains to be realised.
Sometimes when exercising in the aerobic zone, intensity can be increased. This causes the muscles to require more oxygen, which is supplied by an increase in respiration and heart rates. If we increase the intensity to a rate at which the aerobic system is unable to supply the oxygen required, then energy will start to be produced anaerobically. The body will metabolise gluten in the absence of sufficient oxygen to fulfil immediate ATP requirements. This results in lactic acid being produced as a by-product, which then permeates in large quantities to the muscle cells. This is called the anaerobic threshold.
The body responds to changing threshold by:
- Aerobic training (cardiorespiratory system will be improved if the athlete works closer to the anaerobic threshold then the aerobic. Working at this level increases the athletes ability to tolerate lactic acid)
- Strength training (bigger gains in strength will be made if resistance is increased)
- Flexibility training (gains are greatest if muscle are safely stretched further)
Warm up/Cool down
Warming up and cooling down are important elements of all training and performance sessions.
Warm up increases blood flow to working muscles. This increases body temperature which loosens muscles, ligaments and tendons. The increase in elasticity reduces the likelihood of injury. Warmup should also provide an opportunity to activate motor neurons associated with those used in the performance. An effective warmup should be sustained for at least 10 min, with it being much longer for athletes that require explosive movements. Stretching should be avoided until the body is warm.
Warmup should happen in the following order:
- General warmup. A gentle use of large muscle groups in a rhythmic order. This will raise heart rate, and should progressively increase in intensity. Sweat on the forehead is a good indication the body is warm.
- Stretching. Stretch major muscle groups in a slow manner. Hold for approx. 10-30 sec. follow with a similar routine for specific muscle groups used in the activity. Dynamic stretching has also been shown to be useful in preparing muscles.
- Specific warmup. Practice performance like activities that progressively increase the HR and use of muscles/ligaments involved. Should also incorporate skills that will be used, which will help activate motor neurons.
Cool down is effectively the same, but in reverse. It allows for active recovery and gives the body time to return blood to the heart rather than pool in the muscles. Also allows oxygenated blood to flush out waste products and begin to rebuild energy stores. It is an essential component of aerobic, strength and flexibility programs. Should include a period of stretching that enables working muscles to be stretched to their original length.
Physiological Adaptations to training
When people undertake any type of training their main aim is to change some aspect of their body to improve performance. Many of these changes occur in the cardiorespiratory system and lead to an improved ability to deliver oxygen to working muscles.
Rest is a state where no extra demands are placed on the body. Energy requirements are for maintenance of normal bodily functions e.g. breathing heartbeat etc. this is known as basal metabolic rate.
Submaximal exercise is exercise performed at a level that leaves the heart rate a constant rate for an extended period, below its maximum BPM. E.g. jogging, swimming etc.
Maximal exercise is activity that leads the heart rate to approach its maximal level.
Resting Heart rate
At rest the heart will beat enough times to deliver oxygen via the bloodstream to all cells of the body. The minimum requirement for this oxygen is reflected by the resting heart rate. The amount of oxygen required at rest is determined by your basal metabolic rate. When undertaking aerobic training, your heart will significantly change and may lead to a reduction in resting heart rate. In other words, your resting heart rate will fall as your body adapts to the training. Simply, the lower your heart rate, the fitter you are.
The main reason for this fall is the increase in stroke volume. The increase allows more blood to be pumped out per beat. Therefore, to deliver the same amount of oxygenated blood, it will require fewer beats. Resting HR and sub max HR both would fall as a result, however HR during maximal exercise will be the same, however more work will be able to be done.
Stroke volume and cardiac output
Stroke volume is the amount of blood that leaves the left ventricle each time the heart beats. The ability of the heart to push oxygen rich blood towards working muscles is the biggest factor affecting performance. Stroke volume is determined by:
Size of ventricles
Thickness of ventricle walls
Flow of blood
Volume of blood in the body
Training causes the physical size of the heart and ventricles to increase. The increased stroke volume leads to a higher cardiac output, therefore improved performance.
Cardiac output is the amount of blood leaving the heart each minute. This oxygen allows the aerobic system to produce ATP therefore maintain movement. During rest and sub-max work, aerobic training will not change cardiac output results.
Oxygen Uptake and Lung Capacity
The ability of the heart to move oxygen into the bloodstream and remove Co2 is also affected by the size of the lungs and the ability of the blood to absorb and carry oxygen to working muscles.
Oxygen uptake (v02) is the amount of oxygen absorbed into the bloodstream during exercise. The body consumes small amounts of oxygen at rest, however, as exercise commences the mitochondria use more oxygen in the provision of energy. V02 max is regarded as the best indicator of cardiorespiratory endurance. It is measured in L/pm
V02 is generally higher in males because females generally have less muscle tissue and less oxygen carrying capacity due to lower haemoglobin.
Oxygen uptake decreases at a rate of approx. 1% per year after 25, however aerobic training greatly influences this.
If v02 is also hard for a fit athlete to improve, then for an unfit person to improve.
Lung capacity is the amount of air that can move in and out of the lungs during a breath. Essentially, the more oxygen that can be breathed in, the more can be delivered to the muscles, improving performance. With training, vital capacity will increase slightly, residual volume will decrease slightly.
A few adaptations associated with lung function occur because of basic aerobic raining:
- Number of breaths that can be taken during maximal exercise increases
- Size of lungs increases slightly
- Total amount of air breathed during exercise can increase
- Number of capillaries in lungs increases
Haemoglobin levels
Haemoglobin absorbs oxygen in the lungs and carries it to the working muscles via bloodstream. It also plays a role in the removal of C02, but this isn’t as important as the delivery of oxygen. It is contained in RBC, with each cell holding approx. 250 million haemoglobin molecules. Without haemoglobin, we would need to have approx. 80 litres of blood.
Haemoglobin levels increase because of training. Because of training, the body produces more RBC subsequently haemoglobin, because of oxygen deficiency during the training. Altitude training also increases haemoglobin levels.
Muscular Hypertrophy
Refers to increase in the diameter of muscle. It occurs as a result of strength or resistance training. It refers to muscle growth with an increase in the size of muscle cells. Training needs to address the overload principle as well as specificity being important. The extent of hypertrophy depends on:
- Muscle type, white muscle fibres are generally genetically larger in cross sections
- Type of stimulus, low reps with high weight generally yields better results
- Regularity of training, regular training is important
- Availability of body hormones, more easily achieved in males
Muscular hypertrophy will improve performance in strength and power related sports.
Muscle fibres
Two types:
- Red slow twitch (duck)
- Fast twitch generally white (chicken)
Most people have approx. even numbers of both, some individuals have genetically higher numbers of one or the other. This predisposition enables them to excel in different sports.
Slow twitch fibres contract slowly and are better for endurance activities.
Fast twitch fibres reach tension quickly and are better for explosive movements.
Changes only occur in the fibres used in training. Low intensity training will predominantly use slow twitch fibres, so fast twitch fibres need to use a higher intensity.
How can psychology affect performance?
Motivation
Psychology is one of the biggest factors that determines winning and losing at an elite level.
Motivation is what induces a person to act in a certain way. This can be either positive or negative. There is positive and negative motivation, and the influences on behaviour can be intrinsic or extrinsic.
Positive motivation is the recognition of good work. It lasts long and is more substantial then negative motivation.
Negative motivation is the desire to succeed in a task to avoid unpleasant situations. It is more short term compared to positive motivation.
Although both forms are used in sport, coaches need to carefully assess a player’s psyche and treat them accordingly. if motivation techniques are used incorrectly, it can lead to a deterioration in performance.
Intrinsic forms of motivation come from within. They may include the satisfaction of winning, desire, goals etc, and are not necessarily related to any external factors. Self-satisfaction with a performance is referred to as internal reinforcement. Without any type of reinforcement, athletes will find it difficult to maintain motivation. Positive reinforcement and negative reinforcement and both central to motivation.
Central to intrinsic motivation is ‘flow experience’. This refers to a high level of concentration to where the individual is completely absorbed in the task and is maintaining it without conscious effort.
Extrinsic motivation is motivation that comes from sources outside a person e.g. trophies, prize money. Extrinsic often focuses on the product, or what can be gained while intrinsic focuses on the process of becoming better. Whilst extrinsic rewards may change how hard an athlete works, it does not change underlying attitudes in behaviour.
Social reinforcement (reinforcement occurring in front of others) can be used effectively alongside extrinsic motivation. Can be positive or negative.
Trait and State
Trait (A-trait) is an athlete’s general predisposition to perceive a scenario as threatening. It is a personality trait. Varies according to how individuals have conditioned themselves to respond and manage stress. Can be significantly decreased by individuals who the athlete has a firm belief in offering supportive comments and encouragement.
State (A-state) refers to the emotional response of the athlete to a particular situation, e.g. fear, worry , tension etc. it is more specific and is characterised by a state of heightened emotions. May be physically visible e.g. sweating. A certain level of state anxiety may be beneficial in sports where aggression can benefit e.g. rugby. Visualisation and imagery assist in combating this. Examples of where state anxiety can occur is penalty in football, conversion in rugby etc.
Sources of stress
Prominent in individual sports, adrenaline. Characterised by:
- Increased blood supply to working skeletal muscles
- More oxygen to lungs
- Increased glucose production
- Increased sweat production
- Tightened muscles
Stress is a personal attribute and depends on predispositions, such as:
- Past experience
- Routines
- Expectations
- Amount of support
- Frequency of similar occurrences
Factors that produce stress are called stressors, and can develop from:
Personal pressure (pressure imposed by individual desires)
Competition pressure (pressure exerted by opponents on the field of play)
Social pressure (pressure from coaches, peers and individuals held in esteem by the athlete)
Physical pressure (pressure of having to perform learned skills under competition demands)
Together these make up the sources of stress. Other sources of stress include media, personal experience, spectators, injury/illness etc.
Athletes can learn to cope with stress by using strategies such as relaxation techniques, concentration skills and planning strategies. They should also focus on the task rather than the result.
Optimum arousal
Arousal is a physiological process and a necessary ingredient in performance. The athlete will perform a task most successfully when their level of arousal is optimal for that particular task. Generally, athletes with a higher predisposition towards anxiety require less arousal than those with a lower predisposition towards anxiety. Some athletes can achieve optimum arousal by thinking about what they need to do whereas others require input from a coach or peer.
↑A-state = ↓ arousal (generally)
Both over arousal and under arousal can be detrimental to performance. Athletes respond to different stimuli to raise or Lower their arousal. Arousal can be measured by heart rate, respiration, muscle tension, skin temperature. The inverted U theory states that in order for optimal performance to occur, the individual must attain a moderate level of arousal. In this instance optimal doesn’t mean maximal. Too much or too little can hurt an athlete’s performance depending on their sport.
High intensity contact sports have a higher optimal arousal level then low intensity non-contact sports. A rugby player would need a higher level of arousal than an archer. Also, the more difficult the skill, the lower levels of arousal. Under arousal is categorised by lethargy, lack of motivation, with over arousal being categorized by inability to concentrate
Strategies to enhance motivation and manage anxiety
Concentration/attention skills (focusing)
More experienced athletes are able to filter out unnecessary information that doesn’t benefit their performance. They can also switch off their concentration to avoid fatigue but can also return to it easily.
Effective concentration involves maintaining an uninterrupted connection between the task and the execution required.
Concentration can be improved by training that emphasises the process rather than the outcome. When an individual focuses on the process, they give more attention to technique and try to understand the reasoning behind what they are doing.
Types of concentration include:
- Intense concentration (gymnastics, diving)
- Intervals of high concentration with periods of lesser concentration (most team sports)
- Sustained concentration (marathons, triathlon, tennis)
Concentration can be sustained by using well established sub routines, avoiding negative thoughts and utilising positive self-talk.
Attention is vital to concentration in that It can be used to concentrate on relevant stimuli and block out irrelevant ones. Attention is a mental process that is Selective (can focus on some things but not others), shiftable (can change voluntarily or involuntarily) and divisible (can maintain more than one focus at a time)
Strategies that can assist an athlete in concentrating are:
- Set routines (assist with focus and reduces anxiety)
- Cues (verbal, physical, can remind an athlete to focus at specific times)
- Positivity (focusing on positives rather then negatives may reduce anxiety)
- Distraction training (deliberately implanting distractions into training to aid with concentration)
Mental rehearsal, visualisation and imagery
Visualisation involves the athlete to relate specifically to mental images of what performance must be undertaken. It is imagining what the skill or subroutines will look like from their POV
Mental rehearsal is similar but involves also picturing actual performance elements such as crowd, weather conditions etc. both can improve an athlete’s concentration and confidence. It involves the mental repetition of a movement or sequence to increase the mind’s familiarity with the desired motion.
Imagery is used in both and is seeing clearly in the mind what is required in the body in the movement. There are both internal and external imagery. Internal imagery is seeing things from your normal POV, whilst external imagery is from a third perspective. It is suggested that internal imagery is better for overall performance, whilst external imagery is better for learning a new skill or correcting technique
Mental rehearsal provides a clear idea of what has to be done, heightens concentration and narrows thoughts on the task. However, it also requires to be performed immediately before performance, should be of the total performance or of those sections the athlete struggles with and narrow thoughts to exclude distractions
Mental rehearsal allows the athlete to practise old skills, learn new skills, gain confidence, control anxiety and arousal levels and develop coping strategies.
It also allows athletes to picture things not going to plan and work out how they would cope with those situations.
Relaxation techniques
A series of techniques that seek to control the body’s response to stress, often used by athletes to calm themselves, asset with composure. Techniques include:
- Progressive muscular relaxation (relaxing muscle groups using special exercises)
- Mental relaxation (relaxing the body through controlled breathing)
- Self-hypnosis (using suggestion to have the mind accept a particular level of anxiety)
- Mental rehearsal (concentrating on rehearsing the performance of the task)
- Meditation (narrowing one’s thoughts using images and sounds
- Centred breathing (controlling breathing to release tension)
Progressive relaxation
Involves the systematic tensing and relaxing of muscles, if all muscles are relaxed it is impossible to earpiece stress and tension. E.g. make a fist for 10sec, concentrate on the strain in the arm then let the hand relax and continue the process with different muscle groups.
Biofeedback
Uses instruments that measure changes in bodily functions, giving athletes better control of changes. Can measure heart rate, be muscular activity etc. if a person is aware their heart rate has increased they can concentrate on relaxing and lowering it
Goal Setting
Goals provide focus, give direction, help motivate and aspirate. Can be short or long term. Short term goals are important as they can serve as benchmarks by which other goals are measured.
Goals can be process orientated (relating to the quality of the performance) or outcome orientated (related to the result or outcome)
Short term goals are achieved in a limited amount of time and are stepping stones for achieving long term goals e.g. attend 3 endurances training this week.
Long term goals can only be achieved over a long period of time e.g. run the Boston marathon
Behavioural goals are derived by athletes and relate to improved behavioural expectations in training and or competition. They are measurable behaviours rather then aspirations e.g. be more punctual to training, control on field temper
Performance goals relate to an athlete’s desire for success e.g. gold medal
Principles that can aid the formation of goals are
- Make goals specific not general
- Set deadlines
- ensure they are challenging but achievable
A popular guide for goal setting is the acronym SMARTER
Specific
Measurable
Accepted
Realistic
Time
Evaluate
Recorded
Asking who what when where why which can also assist in improved goal setting.
Nutrition and recovery strategies
Programs designed to improve performance must be supported by solid nutritional practices. This involves factors such as what to eat and when to eat
Fluid is important because it is the body’s medium for cooling heated muscles, regulating body temperature and preventing dehydration
Pre-performance
Food consumed prior is only useful if digested and its energy and nutrients made available to where they are required in the body. Common aims are:
- adequate energy/fluid intake
- correct balance of energy sources (avoid excess fat and inadequate carb)
- adequate protein (optimize recovery and gains)
- adequate vitamin/mineral intake (avoid deficiencies)
the main aim is provision of adequate energy along with macronutrients (carb, prot, fat) and micronutrients (vit and min). an individual’s size, metabolic rate and energy expenditure will alter these requirements.
Type of food:
Training diet must provide adequate carbs, moderate protein and low fat (foods higher in fat protein fibre require longer to digest, and consuming large amounts may lead to discomfort).
Athletes are advised to eat mostly complex carbs (pasta, cereal, bread, rice) as they provide slow energy release. Foods containing refined carbs may be used to top up and kj requirements when needed
Glycemic Index
GI categorises carbs based on their effect on blood glucose levels. Foods rated 72 or above are high GI and are good for replenishment. Foods rated 55-70 are moderate GI, below 55 are low GI and are good for slow release carbs. Although both low and high GI release carbs, low GI are thought to have a more sustained release over time, benefiting endurance athletes, rather then the spike that occurs with high GI
High GI (potato, rockmelon, sugar, glucose, sport drink)
Medium GI (popcorn, oranges, porridge, pasta)
Low GI (apples, lentils, brown rice, milk)
Protein:
Made of various combinations of 20 amino acids, its major function is to repair cells in the body and manufacture enzymes. An athlete requires a slightly higher protein intake than a normal person, as amino acids are critical for growth and repair.
If the protein intake of an athlete is insufficient it can lead to early fatigue, inability to build/maintain muscle growth and slow recovery from injury. RDI of protein is 0.8-1.2g per 1kg body mass. Good sources of protein include:
- lean meat (lamb, veal)
- poultry
- fish
- low fat dairy products
- legumes
Fat:
Mobilised as an energy source when the activity is low intensity/aerobic. Excess fat can lead to a storage of body fat, but a small amount of dietary fat is needed for normal body functions. All athletes should manage their fat intake to allow room for carbs and protein to maximise performance. Fats include:
- butter/cream
- animal fat (on meat)
- chocolate
Amount of food:
Food ingested before a performance has potential to cause discomfort. The appropriate amount of food relates to the type of competition, with more sustained events (marathon) requiring more kj to fuel their metabolism.
When to eat:
Most athletes feel comfortable having a meal 3-4hrs prior. Limited solids can be consumed 2 hrs prior whilst carb solution drinks are preferred 30 min prior
Hydration:
Adequate fluid is paramount. 500-600ml of fluid consumed 2-3hrs prior, and 250-300ml in the last 15 min.
Carbo-loading:
Technique used to maximise the bodies storage of glycogen in preparation for high intensity activity >90min (marathon etc.). muscle glycogen levels can increase by up to 1/3. Involves a depletion stage followed by a loading stage to ensure glycogen saturation.
Done by a balanced diet high in carb, complex carbs such as bread and rice are ideal but can be ingested with simple carbs. This is followed by a tapering of training for 2-4 days before competition, enabling glycogen supplies to maximise. (tapering referring to a period immediately before competition where training volume and intensity are decreased).
7-5 weeks before competition that athlete will not consume carbs and train with high intensity and volume
From 4 weeks out to competition day, the athlete will reduce the training and intake carbs of a low GI, allowing the body to absorb them.
This will result in increased muscle and liver glycogen. Delays the point where the working muscles run out of fuel, due to more glycogen in body
During performance
Goal of nutritional intake during performance is to minimize fluid deficit, prevent thermal distress conditions and provide additional fuel source in sports that require it.
Unless the activity lasts longer for 60 minutes, there is no need to supplement fluid replacement with carbs. However, for sports that require it, carb intake during performance provides an additional fuel source and has the potential to improve exercise capacity in situations where glycogen stores may limit performance.
A target of 30-60g f carb per hour of activity is a good starting point.
Hydration during performance is key. Dehydration to just 2% of the athlete’s body weight can result in reduced anaerobic performance, increased exertion, reduced mental function, slowed gastric emptying. It is important athletes start each training or event well hydrated to minimise fluid deficit. Ideally, athletes should drink to a plan based on their own sweat rates. Water is generally good, however sports drinks can be helpful In some scenarios as it can help supply some sodium and carbs, which is important in events undertaken in heat. Consider these points:
- hydrate before, during and after
- drink every 15-20 min while running
- wear light clothing
- avoid activity in times of high temperature
Post-performance
Generally, athletes do not need to do anything special nutritionally post training if their diet is good. However, if the athlete is doing two or more sessions a day, training for prolonged periods, or competing in long events >2hrs recovery can be a challenge.
Processes that recovery encompasses are:
- restoring muscles and livers expended fuel
- replacing fluid and electrolytes
- manufacturing new muscle protein and RBC
the specific food and fluid recovery the athletes adopt depend on the nature of the training session, the goals of recovery are:
- refuel (carbs)
- rehydrate
- repair
- revitalise
a post-performance national plan aims to return the body to its pre-event state as fast as possible, this is best achieved through proactive recovery, meaning refuelling and rehydration begins immediately and continues for 8-12 hrs. The best way to recover is to act quickly and eat foods with high carb.
Replace immediately depleted muscles and liver glycogen stores by consuming carbs ideally within 30 min. foods with high GI are most beneficial.
Rehydrate to replace fluid and electrolyte lost. Aim to replace 125-150% of fluid lost over the next 2-4hrs.
Repair and regenerate damaged muscle tissue. Protein consumed immediately after is absorbed more efficiently and should ideally be consumed with carbs. Optimal amount is 10-20g
revitalise and maintain good immune functions to promote adoption and prevent illness, which is done by consuming carb/protein. Also assists with the body’s adaptive processes.
Use of supplementation
Common today, but effectiveness is often debated. Athletes use supplements due to:
- belief they enhance performance
- Belief their training needs are too high for normal dieting
- Belief they eat poorly or have an unhealthy lifestyle
- Belief in the claims of advertising
Most athletes should be able to meet their nutritional requirements through specialised training diets. Supplementing an athletes diet with extra nutrients may reduce their adaptations.
With a greater focus on drug testing, supplementation has a potential for inadvertent doping, in which athletes test positive for banned substances they were taking as supps.
Vitamins and Minerals
Required for health and optimal performance, deficiencies can lead to fatigue, infection, illness etc.
Main areas to consider are calcium and iron. Some minerals are known as electrolytes, and include sodium, potassium, calcium, magnesium, iron. These minerals form salt that conducts electrical energy needed to keep the body functioning and iron which is used in haem.
Iron and calcium:
Iron depletion is common especially among female athletes, resulting in anaemia (RBC deficiency). Common amongst
- Endurance athletes
- Females
- Vegetarians
- Adolescent males
However too much iron can damage the gastrointestinal tract
Supplementation of iron should occur if there Is large blood loss. One of the major problems of iron deficiency is it alters the athletes diet resulting in too many carbs, as many foods rich in iron are also high in arbs. In this instance iron supplements may be beneficial.
Calcium deficiency is more specific to health. It is vital for bone structure and making strong and healthy bones. Bone tissue quality gradually deteriorates from the mid-20’s and often causes osteoporosis. Also important for bone and teeth formation calcium is found in dairy, leafy greens, veggies and fish. Calcium may need to be supplemented if an individual is allergic to dairy foods.
Some minerals include:
- Zinc (growth and repair of muscle tissue)
- Magnesium (muscular contraction, used in glycolysis, deficiency causes increase requirement of oxygen for sub max output)
- Sodium/potassium (neural transmission, critical for endurance as is often lost through sweat)
Vitamins are not made by body but are required. Needed to sustain bodily functions and help in chemical reactions. Water soluble vit. Such as B and C need to be replenished regularly as they are easily excreted through urine. The intake of excessive quantities of vitamins is not only unnecessary but potentially dangerous.
Individuals who may benefit from vit. Supplementation are those who:
- Are undergoing weight loss
- Endurance athletes (Sweating)
- Large blood loss females (menstruation)
- Adolescent males
- Pre-existing vit/min deficiencies
Important vitamins are:
- Vit B, optimise energy production and build and repair tissue, also vital in RBC production
- Vit D needed for adequate calcium absorption promotes bone health, helps regulate homeostasis
- Antioxidants (Vit C E) protect cell membranes from oxidative damage since exercise increases oxygen consumption therefore oxidative damage.
Protein
Many athletes believe protein supplements are important because of their role in muscle building. Protein’s primary role in the body is to hold cells together and help grow, repair and maintain body tissue. Can also produce hormones and is used in nervous system transmissions. Protein is made up of amino acids, which the majority of which are made in the body, however requires some supplementation from food sources.
Protein supps usually come in two forms:
- Whey protein isolate
- Protein mixed with a number of other nutrients to enhance other muscle groups
Athletes often consume protein supps under the misconception that the extra protein will enable the body to build muscle faster. the body can only utilise a small amount of protein to build muscle, with the res going to different sources. Excess protein can also negatively affect health. On average, 12-15% of the RDI should consist of protein.
Caffeine
CNS stimulant, high levels are not necessary for sports performance, however has a number of affects:
- Increases heart rate
- Relaxes smooth muscles
- Can produce symptoms of anxiety in high doses
Caf. Is absorbed through the intestines. Caf. Does appear to improve cognitive processes such as alertness. however, doesn’t appear to enhance performance in short term high intensity activities e.g. sprinting. It is also a diuretic, which means it may lead to dehydration.
Also has ergogenic aid(substance or practice believed to improve physical performance) properties, as it improves performance by assisting specific metabolic processes. Has been proven to have positive effects in some scenarios such as:
- Alterations to CNS to amend perceptions of fatigue
- Effect on cardiac muscles
- Stimulation and release of adrenaline
- Mobilisation of fats from adipose tissue
- Changes to muscle contractions
Most favourable evidence supporting ergogenic aid properties of caffeine relates to endurance sport such as marathon, whereby it mobilises fat stores to convert them to free fatty acids, where working muscles can make them a usable source of energy. Also believed it promotes glycogen sparing, in which fat is metabolised early sparing finite reserves of glycogen and subsequently prolonging the point where exhaustion will occur.
Large doses of caffeine may result in:
Over arousal
Increased HR
Impairment of fine motor control
the most beneficial time to ingest caffeine is 1 hr before an event
Creatine (Adenosine triphosphate phospho-creatine)
Compound that occurs naturally in the body found mainly in muscle tissue in the form of creatine phosphate, which provides a ready source of ATP to working muscles in times of high demand, with it being synthesised at lower demand to replenish stores.
Produced by body cells and through food intake. The Main source of dietary creatine is animal products. Body has a maximum amount of creatine it can store and once reached will breakdown extra creatine and excrete it through urine.
Little if any benefit of creatine products, as body is unable to store excess. By supp. Athletes are trying to enhance the efficiency of ATP PC system, whilst it can improve recovery rate, it does not extend the length of time performance can be maintained.
Creatine supplementation is done in two ways:
20g (4x5g doses over a day per 5 days)
3g a day over a month
Athletes will choose different loadings based on the goal of their training. Once muscle stores have been saturated they will sustain it with a maintenance dose of 2-3g a day.
Creatine loading may result in weight gain, which results from the body retaining extra water as creatine stores increase. It is a highly specific fuel source and will not be beneficial for athletes who are not already consuming suitable macro/micro nutrient intakes.
Recovery strategies
Athletes need to manage recovery to prevent fatigue, illness, injury, underperformance etc. ensuring the athlete employs appropriate recovery strategies to minimise these. Active rest is still regarded as the most beneficial form of recovery. The aim of recovery is to return to a pretraining/competition physiological and psychological state as quickly as possible, and to optimise chronic improvements in physiological capabilities. Inadequate recovery can result in:
- Incapable of performing at expected standard
- Prone to injury
- Predisposed to injury
- Susceptible to overtraining
Short term recovery refers to activities such as cool-down and low intensity exercises to promote soft tissue repair and disperse lactic acid.
Long term recovery refers to recovery between competitions or following periods of peaking where the body needs to be rested from the demands of physical training. Recovery strategies can be classified as physiological, neural, tissue damage or psychological.
Physiological strategies
Active recovery (cool down)
Focuses on two elements, removal of metabolic by-products and replacing lost fluids and energy rich nutrients. Designed to reduce the occurrence of DOMS. Has benefits such as reduction in blood lactate levels, gradual lowering of core body temp. and psychological benefits.
Hydration
Hydration is important following exercise. Athletes should monitor their body weight and should drink 150-200% of weight lost during exercise in water. Drinks should be cold as this will help reduce the body’s core temperature. Avoid alcohol as it is a diuretic and will reduce the effectiveness of hydration strategies.
Fuel recovery
Paramount to replenish depleted glycogen and blood sugar in the first 30min-2hr following exercise, as this is the time muscles are most receptive to glycogen enrichment, absorbing up to 50% more. Carb to protein should be taken at 4:1. A high carb diet with balanced macronutrients is recommended for recovery
Stretching
Benefits include reduction of muscle tightness and soreness and improvement of join ROM.
Compression garments:
- Decrease swelling and muscle soreness
- Increase blood flow
- Improve endurance and temperature regulation
- Increase force production
Passive Recovery
Resting with no activity, allowing the body to recover from previous efforts by allowing metabolite removal and substrate resynthesis within working muscles.
Neural strategies
Recovery strategies that help the central and peripheral nervous systems recover from high levels of work. CNS is the brain and spinal cord and peripheral is nerves running to muscles. System fatigues due to change in chemicals found in working muscles during bouts of heavy exercise.
Hydrotherapy
Use of water to assist with the recovery of working muscles following exercise. Physiological effects include changes in cardiac response, changes in blood flow and skin muscles and core temp. changes. Types of hydrotherapy are:
- Hot water immersion:
- Approx. 37 degrees C. HWI results in increased blood flow and skin, muscle and core temp. can be used in a spa with water jets acting as a massage.
- Cold water immersion:
- Applying cold water and ice are common for treating acute soft tissue injuries. Used in recovery in the form of baths, ice baths. Submerge for 3-15min at 6-15deg. Benefits include:
- Decreased temp.
- Reduced swelling soreness
- Decreased perception of pain and discomfort
- Increased perception of recovery
- Applying cold water and ice are common for treating acute soft tissue injuries. Used in recovery in the form of baths, ice baths. Submerge for 3-15min at 6-15deg. Benefits include:
If CWI is used within 1 hr of exercise it may have a pre-cooling effect and be detrimental to recovery.
- Contrast water therapy:
- Participants alternate between heat exposure and cold exposure by immersion in cold and warm water. Possible benefits include reduction in swelling, alterations in tissue temp. and blood flow, changes in blood flow distribution, reduction of pain and improvements in ROM
- Pool/beach sessions:
- Pool recovery sessions are frequently used by team sports immediately after competition. Generally, include light exercise and can relieve muscle soreness and stiffness. Studies have indicated P/B sessions accelerate recovery and give lower perception of muscle soreness, possibly due to the buyout effects of the water.
Compression garments
Widely used to treat problems with blood flow. By improving circulation and promoting venous return in a post exercise period, there may be an accelerated inflammatory and repair response, accelerating the process. May also reduce the effect of DOMS due to increased blood-flow.
Massage
Benefits include:
- Increase blood flow, enabling faster removal of lactic acid
- Decreased muscle tension
- Increased joint flexibility
- Decrease nervous system tension
Sauna
Recommended athletes avoid saunas due to dehydration.
Tissue Damage strategies
Cryotherapy
Ice is used to slow down inflammatory processes. The ICER principle is used in the rehab of soft tissue damage. Using a damp cloth to avoid direct contact, apply ice on and off for 10 min intervals up to 40 min. can be repeated periodically for 2-3 days
Compression garments
Promotes blood flow, see previous points.
Psychological strategies
Following activity the body can take some time to return to normal resting levels of heart rate, breathing and temperature.
Relaxation
Choice of methods differs depending on the individual. Debriefing sessions, performance evaluations are necessary but must be positive focusing on the process rather than the outcome. Mind relaxing activities such as reading, music, movies and television are helpful and used by most athletes. More specialised psychological techniques such as progressive muscular relaxation, meditation, visualisation and positive self-talk are realised if practiced often (see previous core 2).
Sleep
Often identified as the most important component of the recovery process. 7-10hrs. additional sleep may slow CNS, lack of sleep however has several implications:
- Reduced focus
Reduced memory
Increased likelihood of overtraining
Decreased physical performance
Can promote sleep by:
Maintain regular sleep cycle
Comfortable sleeping space
Avoid stimulants before bed
Skill Acquisition and Performance
Stages:
A skill can be defined as an act or task. Inherent factors such as age, sex, motivation affect the rate of skill acquisition.
Cognitive:
Beginner, involves much thought and focus, characterized by thinking. Jerky movements, gross errors. Quite a short stage, athletes will make large gains in proficiency. Build simple fundamental skills. Break into smaller movements if necessary.
Employ motivational techniques, keep instructions short and simple, give examples.
Feedback at this stage is important and should be given with visual demonstrations and verbal info.
Associative:
Quite long, athletes may never move past this stage. Movements become more coordinated, and anticipation develops as the athlete needs to think less. They are no longer thinking about body position, but where they are going etc.
Again, important for the coach to give good feedback and accompany it with practice.
Teach movement patterns first then add environmental factors. Use both knowledge of results (how successfully skill was performed, usually given numerically e.g. goals scored/on target, or by supporter’s reactions etc.) and knowledge of performance (way in which skill was performed/executed e.g. correct runup in vball)
More open style practices. Allows athletes to develop kinaesthetic sense.
Autonomous:
Habitual/automatic, improvements come slowly because they are so advanced. Good consistency in performances. Subroutines in correct sequence and temporal patterning well timed. Doesn’t focus on what they are physically doing, instead focuses on what they have to do e.g. strategy/tactics.
Practice must be well organised to maintain this level. Potentially psychological sessions.
Characteristics of the learner:
Personality, hereditary, confidence, prior experience, ability
Personality
Individuals characteristics and way of behaving. Traits are characteristics/features of a person. Personality develops as a result of the individuals’ social interactions and experiences.
Elite coaches recruit not only physically gifted but also those with positive learning attributes e.g. cooperation, willingness, determination, enthusiasm, dedication etc.
Driver – drive, brash tactless, high energy, bold
Expressive – enthusiastic, motivated, communicators, talk rather than do sometimes
Amiable – kind, sympathetic, sensitive, difficulty making decisions
Analytical – detail oriented, can be overly critical, perceptive
Hereditary
Certain features and traits people are born with. Different sports are better suited for different characteristics. Doesn’t inhibit learning a skill but limits success.
Body type:
Ectomorph – tall and thin
Endomorph – hard and muscular
Mesomorph – soft, excess fat
Muscle fibres:
Slow twitch - endurance
Fast twitch - explosive power
Gender:
Affects hormone levels, e.g. testosterone
Race:
Specific genes, different muscle fibres, also social upbringing may influence interests
Height:
Self-explanatory
Confidence:
Critical in skill acquisition and performance of every day tasks. Unlocks creativity and enables people to help themselves and others. Self-image is a big part of this and coaches should aspire to maintain feelings of achievement.
Prior experience
Prior experience can accelerate the learning process, i.e. transfer of learning. Known as lateral transfer (transfer from one task to another similar one) or vertical transfer (mastering lower tasks as a prerequisite for more difficult things). Variable among learners, basic motor skills are generally transferable.
Ability:
Talent. Athletes with greater ability learn new skills faster. Includes perception, capacity to read the game, reaction time and anticipation. Athletes with greater ability also refine skills better.
The learning environment
Natures of the skill:
Open skills, executed in unstable environments (constantly changing) e.g. changing weather, player affected surfaces. Players need to modify technique to adapt. Seasoned players have knowledge but it is difficult for learners.
Closed skills, conducive to learning as no distractions. Environment same each time. Few fit perfectly into open or closed, most placed on a continuum between two.
Gross motor skills, large muscles groups in basic locomotor activities e.g. walking, jumping etc. common in team games. Basis for all movement
Fine motor skills require finesse, more intricate movements with smaller muscle groups.
Discrete skills, brief, well defined actions with a clear beginning and end, e.g. forward roll
Serial skills, number of discrete skills assembled to form a larger skill. E.g. conversion (place ball, walk back, runup, kick)
Continuous skills, repetitive, ongoing and unbroken e.g. jogging
Self-paced skills, athlete controls when to act at what speed. E.g. tennis player decides when to serve
External paced skills, another athlete or the environment has control over timing and speed of execution e.g. receiving a pass or batter receives bowl.
Performance elements:
Decision making:
Made within the framework of rules, conditions, tactics etc. pressure may lead to poor decisions. Improved by:
- Observation, demonstrations etc.
- Questioning, game-like scenarios to see outcomes etc.
- Variation, different outcomes/possibilities
- Creativity, problem solving etc.
Strategic and tactical development:
Strategy (plan) and tactics (action).
Strategic understanding refers to the way the game is played, where players should be when and what to do etc.
Tactical awareness is a way to gain advantages. E.g. 2 on 1 in football, dummy pass.
In tactical games, the learning environment needs to reflect the game environment. The earlier an individual engages in learning tactical aspects the more effective the learning will be. tactical awareness matures slowly through experience.
Technical efficiency: players utilise correct execution of skills.
Understanding: need to fully understand what is required
Skilful execution: consistent and correct execution
The practice method
Massed practice, infrequent breaks between long periods of work. Continuous. Works best when athletes are motivated, fresh. Allows for lots of feedback. Good for learning a skill
Distributed practice, periods of rest/other skills are equal to periods of practising primary skill. Best to spread intensive work more liberally. Works best when an athlete is uninterested, a difficult task. Causes fatigue.
Blocked practice, spending a block of time on one skill
Random practice, two or more skills practice in random order. More learning occurs with a higher degree of contextual interference (changing elements of practice situation)
Whole practice, whole skill is practiced at the same time, develops kinaesthetic sense
Part practice, subroutines are practiced individually. Better for more complex skills.
Task complexity = number of components and intellectual demands
Task organisation = how components are interrelated
Progressive part practice, parts of a complex skill being learnt separately then added together. Useful for beginners.
When speed is predominating early emphasis is preferable. When accuracy is predominating, early emphasis is preferable. However, if attention is directed solely to accuracy, speed will improve.
Feedback
Provides guidance and helps eradicate movement error. Ensures reinforcement of the correct response, motivates athlete, corrects athlete. Can be positive or negative.
Internal feedback experienced during execution, through information received through bodies proprioceptive mechanisms. Includes sensations, pain, general coordination etc.
External feedback comes from outside sources. Comments from a coach, audience etc. example is augmented feedback, additional information used later to illustrate a point.
Concurrent feedback occurs simultaneously with skill execution, relayed through the body via proprioceptive mechanisms.
Delayed feedback is feedback received at a later stage e.g. waiting for the result of a basketball throw (whether it misses, or scores is not known until after).
Knowledge of results suggests how successfully the skill was performed. E.g. how many goals from attempts. Provides information about skill execution. Always external
Knowledge of performance is more specific to the way in which the skill was performed. Can be internal (kinaesthetic sense) or external (coach comment). Gives feedback on quality of execution.
Both KP and KR are used to motivate learners and reinforce what’s being learnt. Most critical at cognitive and associative. Coaches should give frequency at beginning but less and less forcing athletes to learn hats right and wrong for themselves.
Assessment of skill and performance
Characteristics of skilled performance
Kinaesthetic sense:
Kinaesthesis refers to the system of sensitivity in the body. Skilled performer has good control of it, allowing them to ‘feel’ the movement as they perform it.
Anticipation:
Skilled performers better predict what may happen in specific situations. Important in externally paced activities. Provides more opportunity to smoothly execute movement.
Consistency:
Correctly performing the desired movement repeatedly.
Technique:
Practical method of a particular task. Good technique is economical, not using more energy than required, and skilful, aesthetically pleasing, has more chance of being successful.
Objective and Subjective measures:
Appraisal is a dynamic process, in which a decision is made concerning the quality or merit of a performance.
Can be appraised either:
Subjectively – depending on observers’ personal judgement of the performance. Based on personal feelings and influenced by the mind and temperament of the observer.
Objectively – use of instruments such as measuring tapes, stopwatches. Apply the same criteria to measure performance and do not need to interpret info. Based on indisputable facts. E.g. when a batter is bowled out in cricket.
Objectivity runs on a continuum, and can be made more objective by:
- Checklists, including elements, technical correctness, execution etc.
- Established criteria
- Measurement systems, e.g. measuring tapes
- Rating scales
Skill related tests can provide objective measures for evaluation, and can also:
- Predict future performance
- Classify and compare athletes
- Determine achievements
- Act as a learning tool
Validity and reliability
Validity:
A test measures what it is supposed to.
Can increase validity by:
- Using already validated tests
- Strict protocol
- Scaling and weighting is consistent
- Ensure test contains components being validated
Can use multiple tests for multifaceted games e.g. hockey
Reliability:
Tests consistency. Same test, same tester, same subject, same conditions.
Can increase reliability by:
- Procedures, conditions, tester and location kept same
- Same number of trials
- Crowd motivation kept same
Personal vs Prescribed criteria:
Personal:
Based on feelings, visions, opinions and impressions. E.g. coach selecting team for game/spectators’ reactions. Can be bias/incorrect
Prescribed:
Use measurements to increase appraisal/objectivity. Based on numerical info and established criteria. Checklists, rating scales, measuring etc more accurately convert appraisal into meaningful measurements.