Performance Parameters

 

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by Dan Fedoruk

Training is not a simple of working harder and going farther each consecutive practice. It requires a clear understanding of how we physically adapt to matter different work loads and needs to be approached carefully with a considered plan if we are to perform effectively for a specific sport. For us this is not just paddling, it's training to paddle fast. 
As we adjust our level of work and the type of work we do, different aspects of our physiology and metabolism are correspondingly altered to suit the new demands we are putting on our bodies. This is the fundamental consequence of training. Knowing what changes are required and how to go about achieving them is the central objective of a training programme.

For example, muscles require energy to function and will acquire that energy from different chemical sources within the body depending on the INTENSITY and VOLUME of work. How quickly and efficiently these energy sources are mobilized can be changed through a proper training regime. It's all a matter of calibrating or re-calibrating ones physiology to adapt to the energy demands of a specific race; which does not necessarily need take a long time if there is a good fitness base.

Knowing how your body spends energy during a race is absolutely vital so that your work-out develops the appropriate energy system to its best potential; paddling till you drop will not necessarily make you paddle fast! Adjusting your carburetors to get the best speed or mileage out of the engine you have will often have a greater impact than going for more horsepower. There is no doubt a big engine is good, but only as far as it has staying power and can convert muscle to speed. This depends the training the rate of energy expenditure and the means to deal with the waste products that tend to accumulate.

The following sub-section on ENERGY SYSTEMS is provided to outline the basic metabolic processes involved in muscular activity in order to better understand what kind of work needs to be done and how that work will contribute to a faster boat.

Another factor, which effects our performance is the basic composition of our muscles themselves. The actual size of muscles is not as important as how much or what type of that muscle is being used. The sub-section on MUSCLE COMPOSITION will review this aspect and discuss how to best 'wire in' muscle fibre to suit specific performance demands.

ENERGY SYSTEMS

Ultimately muscle cells gain energy from the chemical breakdown of ATP (adenosine triphosphate) to ADP+P (adenosine diphosphate + phosphate). Since muscles store very small amounts of ATP, a regular supply is provided by resynthesizing ADP+P back to ATP, which is broken down again by muscle action, and so on. This activity primarily relies on three sources of fuel to chemically generate energy, namely:

Phosphocreatine
which is stored in the muscles and is available immediately but only for a few seconds of work;

Glycogen
which is stored in our muscles and liver and provides the main energy source for short and middle distance events; and

Fat 
which stored around the body and will be the main source of energy once glycogen stores are depleted only after a long duration such as in a marathon race.

These fuels are derived from the food we eat and when they are broken down, will produce energy needed to provide a regular supply of ATP to our muscles.  
The key to a good training programme is to determine the energy demands of the race and train to improve the efficiency by which the particular sources of fuel are converted to power. The different fuels are mobilized at different times depending on the duration and intensity of work, allowing our bodies to perform a great range of activities, from sprint races to ultra- marathon events.

The greatest concern from a training point of view relates to the limitations of each fuel, the corresponding effects of the by - products which result from energy expenditure and the time it takes to restore the fuel supplies. This is of paramount significant in short and middle distance races where the primary source of energy is Glycogen.

The breakdown of glycogen occurs either in the absence of oxygen, which is called the ANAEROBIC system or in the presence of oxygen which is called the AEROBIC system of energy production. The INTENSITY and duration of work done will determine the degree to which each system will be utilized, which largely effects how quickly glycogen stores are spent and the extent to which biochemical by- products will induce muscular fatigue.

The ANAEROBIC System

As we do work, muscle cells possess the ability to resynthesize ATP from their own phosphocreatine stores for about 8-10 seconds, which is about the duration of a Dragonboat race 'start' (i.e. getting the boat up out of the water and hydro-planing) and/or may be used for the final 'kick' at the end. 
Up until approximately 1-2 minutes of work, energy is produced primarily by breaking down glycogen in the absence of oxygen, which chemically results in the by product called Lactic Acid. During high intensity work, Lactic Acid accumulates in the muscle tissue which eventually results in that uncomfortable burning fatigue sensation, loss of coordination and finally cessation of physical activity within a very short period of time, depending on the tolerance levels of the athlete. This is a local muscle fatigue and will dissipate quickly after a rest. It is not to be confused with a central fatigue where your body just runs out of its principle energy stores ie. glycogen.

Expenditure of energy ANAEROBICALLY will allow for a much higher level of performance and greater speed, however, the process is much less efficient, making huge demands on glycogen stores. Glycogen stores utilized in the presence of oxygen can last up to 2-3 hours, in a low intensity long distance race, whereas at a sprint pace total glycogen stores would be depleted in about 7 minutes; which makes it important to replenish fuel stores quickly between a series of sprint races.

The ANAEROBIC system dominates a work-out once the lactic acid level in most athletes?blood reaches about 4mM/litre which is referred to as the ANAEROBIC THRESHOLD. Corresponding heart rates are about 150-170bpm ( beats per minute), depending on the age and conditioning of the athlete. The maximal levels of lactic acid before ceasure of international ranked paddlers are upwards of 12-13mM/l over 500 and 1000M distances, with corresponding heartrates reaching 195bpm.

In order to improve performance and overcome muscle fatigue an athlete must train largely to cope with excesses of Lactic Acid. By training muscles to adapt to a regular pattern of stress brought on by high intensity work, bodies 'learn' to cope with different energy demands and still function effectively while approaching fatigue due to high levels of lactic acid.

Typically short pieces of high intensity work increases the rate of glycolysis significantly and builds up Lactic Acid very quickly. This must then quickly be dissipated with low intensity muscle movement, followed again by high intensity work etc. This type of work is generally referred to as INTERVAL Training and effects 'Lactic Tolerance' forcing muscles and the body's metabolism to undergo significant changes in order to speed up the rate of glycogen production and to buffer higher levels of lactic acid.

The AEROBIC System

Physical work which results in lactic acid levels lower than 4mM/l ie. the ANAEROBIC THRESHOLD, is normally dominated by the AEROBIC system of energy production. Training which keeps the athlete's heart rate below 150-170bpm, again depending on age and fitness, will result in development of this system. 
After about 1-2 minutes of work, the heart and respiratory rates will increase sufficiently to carry an adequate amount of oxygen into the muscles which will allow energy to be produced utilizing the AEROBIC system. The greatest benefit of oxygen presence during the breakdown of glycogen is that energy is produced much more efficiently, without the lactic acid by-product which causes fatigue in the ANAEROBIC system.

An overlap between the ANAEROBIC and AEROBIC systems actually begins at about 60-70 seconds into the race. Since most Dragonboat races are between 2 1/2 minutes (650m) to 4 minutes (1000m) the AEROBIC system will contribute to about 50% of the energy demands of the event.

Improvements in an athletes 'Aerobic Capacity' generally results from a regular routine of larger VOLUME, low intensity exercises compared to what would be experienced in ANAEROBIC training. The general effect is in development of the cardio-vascular system which will provide for greater volumes of blood to be pumped by the heart carrying larger quantities of oxygen from the lungs to the muscles. The heart muscle can be developed much in the same way as skeletal muscles increasing the heart's capacity for blood and its stroke volume by pushing work loads to maximal effort, relying on rest intervals to clear the products of anaerobic metabolism.

Superior development of the cardiovascular system alone, however, will not bring about higher performance if the local muscles doing the work are incapable of accommodating the large oxygen supplies. 'Specific Aerobic Capacity' must be trained as well by increasing the blood capillary density and making other physiological changes to the specific muscles involved in paddling such as in the arms and torso.

A greater 'Aerobic Capacity' will increase an athlete's energy resources for the race and will allow faster recovery time after a high intensity work-out during the training season. It is for this reason that teams are encouraged to include longer distance running, rowing or paddling into an off season exercise regime.

In order to get any AEROBIC 'training' benefits of exercise an athlete must work-out at a level of intensity which is between 70% to 85% their maximum capacity for work. In precise terms 70% would relate a lactate concentration level 2mM/l with a heart rate of about 130bpm for most athletes and 85% intensity would produce a lactate level of 4mM/l with a corresponding heartrate of 160bpm to 170bpm. This can vary from athlete to athlete as some individuals will have a threshold level of 3mM/l while others are higher. In practice, few athletes can "feel" the difference between energy systems and very often work at an intensity which is too high or too low for a specific training goal, thereby reducing the positive effects of the workout.

In this regard it is helpful if each athlete could know their own personal heart rate range so that they can work according to prescribed levels of intensity.

A rough guide to an individuals personal work-out range can be roughly calculated using a the following equation

[220 - (your age)] x .7 = your minimum work-out heart rate


[220 - (your age)] x .9 = your maximum work-out heart rate

The level of intensity experienced in a work out can be measured in relation to this range. Typically an athletes heart rate paddling is about 90% to 95% of their maximum possible, with an oxygen intake of about 85% their maximum potential.

Attention to heartrate levels is one of the better methods of measuring work within a practice and it is worth determining the precise lactic levels associated with heartrate readings either with a C1 ergometer or a paddling tank analysis. It is important to regularly re-test these figures since an athlete's Threshold heartrate will increase as they develop a greater aerobic capacity, though generally maximum heartrate will remain constant. For a well trained athlete, the difference between Threshold and Maximum heart rates is between 5 to 20 bpm, while untrained individuals will vary between 20 to 27 bpm differences.

It is equally important, however, for an athlete to learn to feel for the level of intensity they are trying to train to. Heartrates can vary considerably due to the effects of stress, climate, illness and just plain "cardiac drift" where the corresponding heartrate for a given intensity of work can increase slowly during a practice.

General Nutrition and Energy Concerns
'

We are what we eat' and on the training front what we eat seriously effects our performance both during our work-out and in a race. A detailed nutritional programme can get rather complex and is subject to personal interest, however, there are some basic fundamentals which will help to maximize your energy resources for training and generally make you feel better.

The best energy source is from complex carbohydrates such as breads, pasta or rice (and BEER if it's the thick and heady type). In fact a high carbohydrate diet can increase your energy resources for 2-3 hours of training time whereas a low carbohydrate high fat diet can have you running out of steam within 1 hour of work. It is important to drink plenty of water along with such a high carbohydrate intake since the metabolic processes involved with this fuel source can leave you dehydrated.

Fats generally have a low training benefit and we get too much of those without even trying. The problem is that the utilization of Fat as an energy source demands a much larger oxygen requirement which will become a limiting factor to performance. "Hitting the wall" in a long distance event occurs when glycogen stores are depleted and continued activity must draw solely on fat stores for energy, which inevitably slows the race pace since oxygen input becomes less efficient. There is an argument, however, that too much reliance on carbohydrates and no fat will under train your body's natural ability to use fat as fuel, and therefore limit performance when it's needed in longer distance events. A good balanced diet seems to work the best.

In any event, it is advisable to lay off of foods which contain fat during race day since the body's natural tendency is to first utilize and fatty acids floating around your blood before mobilizing glycogen for energy. Since this process requires more oxygen, your performance in a race could drop by 10 or 15% of your maximum capability in order to compensate for the less efficient metabolic activity. A carbohydrate rich snack 1 to 1 1/2 hours before each race or practice is advisable to offset this tendency by acting as a 'fatty acid' buffer.

Common sense dictates that you should avoid training within 2-3 hours after a large meal, though a light snack which contains no fat, such as fruit which is digested quickly and easily, can be beneficial to a long workout (coffee also can give you a good caffeine buzz). Simple sugars such as those in a chocolate bar or coke will give you a quick burst of energy, but is followed soon afterwards by a glucose decrease in the blood stream; and its difficult to anticipate when this will happen - you may get all pumped up ready for an event only to find that you are all tapped out once you get in the boat.

Protein in your diet has little effect on performance though it is vital to repair the bodies muscles which are damaged after a work out. It is important, particularly after an intensive practice, to have a small snack such as peanuts or a milkshake to quickly replenish the body's stores immediately after exercise (you can do your serious eating an hour or so later). Also a quick carbohydrate rich snack within 1 or 2 hours after a training session will be extremely beneficial to replace depleted glycogen stores in the most efficient manner.

Alcohol consumption will impact performance partly due to dehydration but more importantly as it interferes with recovery processes particularly if consumed right after a practice.

Fuel Consumption and Fluid Replacement During Racing


Racing for distance involves a fuel management and fluid replacement regime which goes beyond daily nutritional patterns. This would also become an issue when training particularly for long distance outrigger or dragon boat marathons though it is also important during sprint race regattas where the energy demands far exceed normal daily activity or training.

While a sprint race may be only 3 minutes long the energy demands are great, and the cumulative effects of events which last up to 4 days can be taxing on energy stores. It is helpful begin to increasing carbohydrate consumption as early as 5 days before a big event or training session so your body can make the most out of its potential energy stores. The most critical period is 48 hours before a race where 95% of your diet should be carbohydrates and you're snacking hourly! Regular intake should continue throughout the race day.

Carbohydrate rich drinks or snacks are also available to provide a quick energy source before and after races and can provide a valuable source of fuel during a race or large volume practice. You can count on carbohydrate stores lasting up to 2 or 2.5 hours during a race, so if the expected race or practice session exceeds this duration it will be important to take on fuel as you paddle.

The pattern for fuel expenditure is generally as follows:

1. blood glucose will first be spent within 30 minutes;
2. glycogen stores in the muscle are depleted within the next hour;
3. glycogen stores in the liver follow and are depleted by 2 - 2 1/2 hours of work;
4. fat becomes the only source for fuel after 2 1/2 hours.

As a rule, for long distance events, carbohydrate replacement should begin about 1 hour into the race and should be continued at 15 minute intervals to provide a direct source of fuel in the blood. Determining the rate of caloric expenditure should give a pretty good idea of the amount of fuel required to keep you going. Every athlete is different, however, and it is important to each person in the boat to know when they need fuel and how much they need.

Of course everything depends on the intensity at which you are paddling. At very low levels of intensity fat is utilized as the principle source of fuel, not glycogen. Glycogen is required only when the work level is more extreme. Often marathon runners will train for long duration's at a low intensity to develop a metabolism which utilizes this fuel source early, saving their glycogen stores for the big push in the race. Most marathoner's will start out at a low intensity and then build, rather than starting out fast and settling in. This will conserve vital glycogen stores and avoid early accumulation of lactic acid which your body will labour to breakdown at the front end of the race.

WATER! It is vital to consume fluids at during long races or during race days specially if the climate is hot and humid. You can loose up to 3% of your body fluid in less than two hours on a hot day, which can cause severe trauma to you system. For some of us that means up to 3 litres of water which needs to be replaced even during a race! This is exacerbated by the demands that carbohydrate mobilization has on you water reserves.

NEVER underestimate the need for water. Hydration should begin hours or better yet days days before a race or long training run, even if it means getting up five times in the middle of the night for relief. Urine that is thick as syrup means your blood is probably just as thick, that can result in a high heartrate and renal shut down.

MUSCLE COMPOSITION

Type of Fibre
The basic composition of muscles involves three main types of fibre, namely:

25 - 45% Slow Twitch (aerobic)

48 - 38% Fast Twitch Oxidative (aerobic/anaerobic)

28 - 16% Fast Twitch Glycolytic (anaerobic)

All of us have varying percentages of each type of fibre within our muscles, which is highly dependent on our genetic make up. We cannot change that basic composition as its something we are born with. Each type of fibre is good at doing a certain type of work and responses to a specific level of intensity. This explains why some paddlers may be better at sprints than distance.

For low level intensity work, Slow Twitch Muscle is predominantly used. It is small in size and functions efficiently in the presence of oxygen without suffering fatigue primarily due to the higher density of capillaries and mitochondria enzymes. This why it is know as Red muscle (like the red meat on a turkey leg). This also allows it to utilize fat for fuel easily and why more fat is burned during low intensity exercise than glycogen.

The draw back is that slow twitch fibre produces a low force and is slow to contract, hence the name slow twitch. The glycogen capacity is also low, relying on blood to import necessary fuel. Whilst it may be ideal for long distance racing, it is not very useful for sprinting.

Fast Twitch Muscle on the other hand contracts fast and produces a much greater force when the intensity of work requires it. It is a larger muscle type with greater capacity for glycogen storage. The down side is that it fatigues quickly. This type of fibre can produce a lot of power, but not for very long partly due to the low capillary density. Hence the term White Muscle (like the white meat from a turkey breast).

Fast Twitch Oxidative muscle has a greater density of capillaries and mitochondria than Fast Twitch Glycolytic muscle which a gives it the capacity to function aerobically to a certain degree. It cannot produce the same force as Fast Twitch Glycolytic muscle, but it can resist fatigue better.

Fast Twitch Glycolytic muscle relies almost entirely on local glycogen stores for fuel and, though it produces the greatest force, it is the quickest to fatigue. This type of muscle will not be utilized until the intensity of work is maximal, such as in a short sprint or finish of a race.

Fibre Recruitment


Recognizing the differing characteristics of muscle type and realizing that different races demand use of different muscle type is of fundamental import to developing a training regime for a team or individual. Slow Twitch fibre cannot be converted to Fast Twitch fibre, but to a limited degree, Fast Twitch Glycolytic fibre can be converted to the more aerobically prone Oxidative type if the training is right.  
Each muscle type only responds to a specific intensity of work and therefore demands a training programme which will vary the work load to target different fibre type. Low intensity work will only train Slow Twitch fibre. Fast Twitch fibre will only be recruited when the intensity of work ie. speed increases beyond a point when the Slow Twitch can no longer keep up. Fast Twitch Glycolytic muscle will not be recruited until the work load reaches maximum intensity. If maximum intensity is never achieved, this muscle type will remain untrained and will not contribute to a better performance.

Long distance marathon runners utilize little Fast Twitch fibre and therefore rarely need to train for long at maximum intensity. For very short dragon boat or outrigger sprints, on the other hand, training must predominantly target Fast Twitch fibre recruitment. As races are usually 2 - 5 minutes long, training should ideally focus on developing Fast Twitch Oxidative fibre to the extent that exercises should seek to convert Glycolytic fibre to Oxidative fibre through interval work.

Even in long distance outrigger races, paddlers will never-the-less confront a full range of demands which require extreme effort, such as catching a wave or breaking out of a pack. Whilst Fast Twitch Glycolytic fibre is not as important, Fast Twitch Oxidative is. In distance races, however, there will be a much greater reliance on Slow Twitch muscle fibre.

The effects of training cause muscle fibres and their associated nerves to be recruited in a specific pattern. The effects of training with good technique allow for the minimal number of fibres to be recruited for the desired level of work and thus not waste energy committing to unnecessary movement.

Another implication of specific fibre recruitment is that warm up exercises should target ALL fibre types which will be required in a race. To neglect say Fast Twitch Glycolytic fibre during a warm up may interfere with maximal performance and could result in injury during the race when this fibre type ie recruited into action.