Dehydration Myths: a Thirst for Knowledge

In the latest SwimCoachStu post, I have shared the work of a fellow coaching colleague, Coach J. Macpherson-Stewart (SwimCoachJM-S) – from Free Style Swimming Club, who debunks the prominent lore surrounding hydration in swimming and, more widely, sport. 

Over the weekend, at a local District Championship meet, I became very aware of the large volume of water bottles – filled with a variety of fluids and, of various sizes – that lay across the poolside. This is just one example of the many dogmatic practices which continue to exist within the swimming sphere. It is a belief-based habit which has the potential of having severely detrimental effects on an athlete’s performance and, health. SwimCoachJM-S continues…


I was once at a swimming presentation where the then Scottish Director of Coaching and Development implored his audience of coaches to “throw kids off the poolside” if they didn’t bring a water bottle with them. Continuing that afternoon on the poolside itself I watched as a member of that same audience stumbled over one of those very water bottles referred to earlier in the day and nearly came a cropper; I saw swimmers interrupting the focus on the set they were doing by the distraction of finding and then drinking from their water bottles; and then I watched the subsequent trail of the same swimmers leaving the poolside to go to the loo. Mmm…

The reason for my cynical “mmm…” is that all this flies in the face of science. With few exceptions, the prevailing requirement to bring a water bottle on to the poolside at each session and the encouragement swimmers then get to make sure they drink regularly from them is an unnecessary pre-occupation particularly knowing the kind of predictable consequences I witnessed that day.

The demand for every swimmer to bring a water bottle with them into the training pool has its roots in practices used in the running world which have in turn been driven by the commercial interests of the sports drinks industry. Tragically, the cost of this to the sport of running has been high indeed with over 1,600 reported cases and 12 deaths in the last 15 years (including two in separate London Marathons) from exercise-associated hyponatremia (EAH) – a condition brought about by drinking too much.

Despite these horrifying statistics, the mythology that supports the practice is still being widely repeated revolving as it does around three underlying beliefs: that dehydration will inevitably occur in all athletes who exercise for anything other than a short of amount time; that dehydration is the single most important factor explaining reduced performance levels during prolonged exercise; and that dehydration plays the central role in any instance of collapse and heatstroke there may be in endurance athletes. Since the development of the drink Gatorade in the late 1960’s, this faux science, for that is what it is, has been cynically, and very profitably, peddled by the sports drinks industry even though the wider published evidence paints a quite different picture. In his definitive text, Waterlogged*, Professor Tim Noakes has finally put the record straight to reveal the extent of this misinformation and to demonstrate quite unequivocally that the problem is a problem that would never have existed had there not been millions of dollars to be made. So what are the facts and how should they be interpreted specifically with respect to swimming training?

First of all, our unique evolution as a species has resulted in the human body being amazing well adapted to deal with periods of transient dehydration for up to as much as 8 hours. This evolutionary adaptation arose from the need of Homo sapiens to run long-distances in the heat to pursue and kill energy-rich animals for food. The result was a superior capacity to regulate body temperature when exercising in hot conditions which allowed our ancestors to even run antelope to ground in the heat of the middle of the day.

But let us return and consider each of those erroneous underlying beliefs in turn. Evidence shows that we carry a substantial fluid reserve that simply does not need acute replacement during exercise. This reserve takes the form firstly of metabolic water that is released in two ways: as a by-product of the cellular oxidation of carbohydrate, and as water molecules that are released from their chemical bond with stored glycogen as it is freed and used; and secondly as additional free fluid contained in the intestine. The water reserve referred to here is considerable and even conservative estimates suggest that this available reservoir is likely to easily be in excess of 2L in a mature adult. What this means is that during prolonged exercise (a 2 hour swimming training session, for example) losses of up to 2kg in body weight should not be immediately associated with dehydration and should not be expected to have any deleterious effects on performance. This reserve is easily replaced by drinking normally after the end of the session, often simply with the next meal.

With respect to the second underlying belief, evidence shows that dehydration has little effect on body temperature response during marathon running, for example, and drinking more does not necessarily contribute to better performance. There is no direct evidence that exercise performance is impaired in those who lose weight during exercise provided they drink to the dictates of thirst (I shall come back to this later).

Finally, there is no evidence that dehydration plays any role in the causation of heatstroke. Rather it appears to be increasingly the case that a complex combination of factors contribute to its occurrence the discussion of which goes beyond the scope of this article. Suffice it to say that it is associated with moderate to high intensity exercise of relatively short duration often undertaken in unkind environmental conditions.

What emerges from this is that the natural behaviour modification mechanism that has evolved, that of thirst, is a very sophisticated and perfectly adequate means through which we can maintain our levels of hydration within safe limits. When you reach a point of about 2% dehydration, you will begin to feel thirsty and start looking out for something to drink. Even if there’s nothing available, it’s not the end of the world – in a normal training or racing context there is plenty of time to rehydrate once you’ve finished. At this level of dehydration there are no untoward effects or dangers, and should your levels of hydration continue to decrease, so your desire for water will increase – in other words you will know when you absolutely need to stop to get a drink. The best advice is quite simply, drink according to your thirst – you need do no more than this.

If now, however, we turn our attention to how this applies to swimming training in particular, there are several additional factors that clearly distinguish it from most other popular sports and these need first, to be identified and then to be considered in the light of the above. Perhaps the most significant difference lies in the fact that swimmers are water-cooled. Typical pool temperatures of 28-30°C and the relatively high specific heat of water mean that convective/conductive heat transfer from a moving swimmer to the water is substantial, the faster the swimmer’s speed through the water the greater the heat loss. Body heat is actually lost some 25-30 times faster during swimming than during cycling or running at equivalent ambient temperatures, the greater the temperature gradient between the skin and environment, the greater the rate of that heat loss.

Secondly, the normal major avenue of human heat dissipation during exercise, sweating, is compromised in water since without evaporation no heat can be lost from the body via this mechanism though limited evaporation from wet body parts above the water will still take place. Sweating does certainly occur in the water during training but is unlikely to account for amounts anywhere near the 2% thirst threshold level mentioned above. Thirdly, the total muscle mass involved in swimming is less than in many other non-aquatic sports and consequently the metabolic heat produced is likely to be proportionately less. Fourthly the age and maturity of the swimmers involved needs to be taken into account: because of their larger surface area-to-body mass ratio, children lose heat more readily than adults in the same situation. The thickness of the subcutaneous fat layer also plays a significant role with the result that swimmers who are small and lean are likely to lose body heat more rapidly.

Finally, we need to add one more factor to the mix: immersion diuresis. Explained simply, a combination of cold and the external water pressure brings about a rapid increase in plasma volume which the body then attempts to correct by increasing urine production. The natural consequence of this is an increase in the frequency of trips to the loo though the effect has been shown to be significantly less in trained swimmers when compared with sedentary controls.

Well, dear reader, it may well be that it is your head that is now swimming! We are faced with a series of seemingly conflicting influences which ultimate combine to determine our individual levels of hydration during training. The key word here is individual. There is no fluid replacement protocol that is going to suit even one single member of any particular swimming squad. There is however, a single individual solution….

No-one at Free Style is expected to bring a water bottle with them to training and they certainly will not be thrown off the poolside if they don’t! Not that water bottles are banned, but once swimmers have a better understanding of the whole area, they find out for themselves what best suits their needs. An odd water bottle sometimes turns up (probably more as a result of parental concern) and we have no problem with that providing the swimmer only drinks from it if they become thirsty – sip-aholics are given short shrift! Should anyone during a session become thirsty then they are quite at liberty to return to the changing room at an appropriate point to get a drink. It has been a few years now since anyone has even done this. In fact the real problem for us, and I suspect for many other Scottish swimmers, the younger ones in particular, is actually quite the opposite from the non-existent problem that water bottles presume to address and that is, how to stay warm enough in the water to train effectively. The water cools us so effectively on occasions that body heat loss is greater than its heat production. Some of our leaner, mainly younger, swimmers have had to be encouraged to wear close-fitting thermal tops in training and on occasions we have been known to take warm showers between sets rather than end up uncomfortably cold in the water and consequently losing focus.

So where does that leave us then? During land training the correct advice is quite clear: listen to your body and only drink when you are thirsty from an available source of water which may or may not be your own water bottle, and at the same time understand as well that any other advice is the result of targeted manipulations by industries whose principal focus is their own commercial well-being and not necessarily yours. In swimming sessions leave your water bottle at home if you find that generally you do not get thirsty and in the unlikely event that you do, wait until you have finished the set you are doing and then take a few gulps from the nearest water fountain, or simply wait until the session is over – you’ll have plenty of time and opportunity to rehydrate then and you will come to no harm nor will your performance be affected in the interim. That’s it – the mythology has been exposed!

From,

SwimCoachJM-S

References
*Noakes, Tim (2012) Waterlogged: The Serious Problem of Overhydration in Endurance Sports. Champaign, Il: Human Kinetics.

The Limits of Today’s Swimming Programmes

The majority of swimming programmes used for training swimmers of all ages, across the world, limit themselves in one way or another. Although many coaches are embracing the ever-increasing research into swim training, a huge number are still using yesterday’s methods to train their athletes – inhibiting them from progressing further in their sporting careers. I have addressed the training methods which create these restrictions and introduced how coaches and clubs can move into using tomorrow’s practices, today.

Traditional Training – Garbage Yardage

Firstly, traditional training programmes are based on long slow swimming, or in other words, “garbage yardage”. Swimming at speeds of low intensity does not enable a swimmer to meet the demands of any pool events, in both physiological and psychological terms. As technique is directly related to the velocity swum, swimming at slow speeds will not allow the transfer of the swimmer’s technique into faster swimming. Studies have observed that, although, swimming at speeds of a low-intensity will improve the slow component of aerobic metabolism – a feature useful perhaps to open water swimmers – this is not associated with performance in in-pool events.

Hellard et al., 2010, identified that the slow component of the aerobic pathway is related to long-distance slow swimming – supporting that this is a capacity which would not be useful to anyone other than open water swimmers. Matsunami, M et al., 2012, observed that endurance training, after a lay-off period, improved endurance factors quickly in the first four weeks, however, no further improvements occurred. There have also been research papers which conclude that higher-intensity training causes quicker and higher levels of adaption than low-intensity training. Johansen et al., 2010, demonstrated that “Twelve weeks training consisting of doubling the amount of high-intensity training and reducing the training volume by 50%, increased abilities,” “to reach higher maximal velocities (~5% increase) over 100 m without compromising endurance capacity.” This is supported by numerous other studies which promote high-velocity swimming over lower-intensity.

High Intensity Swimming is Not Enough

However, merely creating a programme which is solely high-intensity work, with a reduction in total distances than traditional training, is only one step in the ladder. Don’t get me wrong, hearing of any coach who has moved their programme into the 21st century is a delight and their swimmers will certainly reap the benefits – but only so far. Training, if it is to improve performances consistently, must be conducted at race-velocities. Swimming slower, however fast, does not meet the crucial principle of specificity. An athlete who has a very impressive VO2max or who can swim or long distances at 80% max heart rate may be very fit but what has that got to do with performance?

Well, not a lot. Although a few (and I emphasise the latter word) studies have shown a correlation – a poor one may I add – between VO2max and other such measures concerning performances, there are other studies which demonstrate why time should be better spent swimming at race-pace. For one, as mentioned above, technique is directly related to the velocity at which one swims; due to the neuromuscular element of swimming. To perform desired technical movements in a race, the swimmer must repeat the actions, in training, at race-pace. Pelarigo, 2010, and Toussaint et al., 1990, concluded that race-pace training is essential as techniques change with velocity.

The other way to think about the above statement regarding the relationship between velocity and technique is that the energy demands will, if performed at race-pace, meet the same (or very similar) demands as that within a race; that is, if you conduct the race-pace training in the correct format. Race-pace training which causes such fatigue that the stroke begins to break-down should be deemed useless. Under these conditions, the desired technique is no longer maintained. Specific distances, repetitions and intervals should be adhered to, to optimise race-pace training.

Ultra-short race-pace training (USRPT) is an ideal platform as it provides an optimal way in which to conduct race-pace training – optimally improving the aerobic and anaerobic capacities of the athlete, as well as meeting the specific demands of a race. A comprehensive database on USRPT can be found at the following link: http://coachsci.sdsu.edu/swim/usrpt/table.htm

Individuality

Another essential principle of training in sport is individuality. Every swimmer, even when grouped in lanes of very similar abilities, will still contain individuals who are each physiologically different. Thus, a coach who is providing a one-size-fits-all programme for all swimmers is committing a great injustice – even a workout which has been tailored for individual lanes does not go far enough (although it’s a start!). As a coach, I fully appreciate the seemingly impossible task of creating a programme for each athlete; however, it may be a lot easier than you may think. Following the principle of specificity, all swimmers should train at a) their race pace and b) meet the same energy demands of racing. When training, swimmers should cease the race-pace set once they begin to miss their target, i.e. their race-pace target time. This rule ensures that swimmers are only training at their race-pace and are not swimming under conditions which are not related to those of a race. USPRT embodies this principle of individuality. It works on a format which provides the swimmer, when they fail a to meet their target time, a break to recover before continuing until they once again fail to meet their time; after that, they cease the set and commence a recovery. A specific guide to conducting a USRPT workout can be found here: http://coachsci.sdsu.edu/swim/bullets/47GUIDE.pdf

Extra time

One of the huge advantages of embracing the URSPT programme is that, due to the reduction in volume, an increased amount of time becomes available to allow the coach to develop swim skills e.g. turns, starts, etc. These are skills which are often neglected, or are rushed when included, due to the desire of traditional coaches to “get in the yards.” A swimmer may possess a high standard of technical ability; however, they “fall by the wayside” due to their low standard of other swim skills – another limitation which is overcome by the increased time provided by the reduction in volume.

Social life…What Social life?

Almost every swimmer I’ve met, past or present, has complained that as a teenager they have no time to do other activities. A big one is having no time to see friends. Many teens leave the sport due to the time they are expected to put into their training or continue, with the mindset that it is a necessary sacrifice. It is not! With USRPT, the massive reduction in volume from traditional training allows athletes the time to enjoy their sport, be successful, but also have fun doing other things – spending time with friends, participating in other sports, etc. This should be seen as a major limitation in swimming programmes and needs to be addressed to allow our young swimmers to become the well-rounded individuals they are entitled to become. Too many have been made to believe this is an evil that they have to endure.

Closure

This article has attempted to demonstrate how there are a number of factors in training programmes which can limit the progress of swimmers. It can be concluded that although, high-intensity swimming is a step in the ‘right’ direction, it doesn’t go far enough. To ensure the principle of specificity is met, training of all forms (technical, conditioning, skills, etc) must be conducted at race-velocity. Individuality is another important factor in a swimming programme to ensure every swimmer is being trained optimally. USRPT was recommended as the platform in which to overcome these limitations – which has been designed to tax the aerobic and anaerobic systems greater and more effectively than high and certainly low intensity training, whilst remaining tailored for each swimmer, due its set guidelines, and specific to the demands of race – physically and mentally. USPRT has been created to remove these listed limitations and should be embraced by all coaches in order to provide swimmers with the best opportunity to achieve their sporting goals. As a direct result of implementing the USRPT programme, extra time becomes available for skills training and athletes are able to enjoy great (greater) success whilst enjoying everything a teenager should be allowed to enjoy…without having to choose between the sport they love and having time do other activities they want to do. This also provides a solution to the old adage, in swimming and other sports, of teenage athlete retention.

Yours in Swimming,

SwimCoachStu

References

Hellard, P., Houel, N., Avalos, M., Nesi, X., Toussaint, J. F., & Hausswirth, C. (2010). Modeling the slow component in elite long distance swimmers at the velocity associated with lactate threshold. A paper presented at the XIth International Symposium for Biomechanics and Medicine in Swimming, Oslo, June 16–19, 2010.

Matsunami, M., Taimura, A., & Mizobe, B. (2012). The role of high volume endurance training in competitive swimming. Presentation 1564 at the 59th Annual Meeting of the American College of Sports Medicine, San Francisco, California; May 29-June 2, 2012.

Johansen, L., Jørgensen, S., Kilen, A., Larsson, T. H., Jørgensen, M., Rocha, B., Nordsborg, N. B. (2010). Increased training intensity and reduced volume for 12 weeks increases maximal swimming speed on a sprint distance in young elite swimmers. A paper presented at the XIth International Symposium for Biomechanics and Medicine in Swimming, Oslo, June 16–19, 2010.

Pelarigo, J. G., Denadai, B. S., Fernandes, B. D., Santiago, D. R., César, T. E., Barbosa, L. F., & Greco, C. C. (2010). Stroke phases and coordination index around maximal lactate steady-state in swimming. A paper presented at the XIth International Symposium for Biomechanics and Medicine in Swimming, Oslo, June 16–19, 2010.

Toussaint, H. M., Knops, W., De Groot, G., & Hollander, A. P. (1990). The mechanical efficiency of front crawl swimming. Medicine and Science in Sports and Exercise, 22, 402-408.

Youth Swimming: Coaches, Poolside helpers and Volunteers

Vital to the development of athletes, of all ages and sports, are the army of coaches – the vast majority of whom are unpaid volunteers. Attempting to run a session on your own with 20+ young children, all bursting with excitement, can be a near impossible task. The life-line for squad coaches is the ability to delegate tasks and lanes to those offering assistance.

Once you have a few willing volunteers, the first decision you need to make is what you would like them to do. You should provide each person with a role in the squad and also delegate tasks to them – this allows your assistants to feel more part of the team and provides them with motivation to attend sessions. Roles and functions can be wide ranging, of which, a few are listed and discussed below:

Lane coach – You, as the head or lead coach, should delegate one or two lanes to a ‘lane coach’ who can supervise the lane activities, time-keep, teach and maintain discipline. This allows you to focus on individual swimmers or one lane and prevents you from doing everything – freeing you up to provide technical feedback.

The lane coach does not necessarily need to be a coach, he or she could be a parent who can time-keep, etc.

Timers/ counters – As mentioned above, you can employ family and friends to time swimmers and/or count laps.

The Swimming Sergeant Major – You will have all seen the military films where the scary looking senior Solider, with the moustache, shouts and screams at the other junior soldiers on the drill square. Well, you can employ a less scary version onto the poolside to maintain lane discipline and ensure correct behaviour. Whoever is nominated to this position should, under no circumstances, shout at any swimmer. They are there simply to, as explained above, free the hands of the head coach by having a civil and calm conversation with individual swimmers if things begin to get a little wild in the pool or proper lane etiquette is not followed.

The lead/squad/head coach still has overall responsibility for ensuring the safety of all swimmers in the pool as well as maintain behaviour.

The Hawk-eye – An adult helper who is used to spot a particular (single) fault in the swimmers, which the lead coach has instructed swimmers to correct in that particular session e.g. breathing out of a turn. It allows the coach to focus on other technique elements and the kids love calling the designated adult the “hawk-eye!”

All coaches and helpers should be briefed on the aims of the session, including, what the programme will involve to meet those aims. The session’s technical points should be listed and explained; this should include explaining how you’d like the points to be taught and showing the coaches how to conduct any demonstrations, e.g. how you’d like to coaches to re-create the kicking action of breaststroke on the poolside. It is essential that all coaches “sing from the same hymn sheet”, or else, the swimmers will receive mixed messages. This is counter-productive, and opens up the possibility of providing incorrect instruction.

A coaches meeting once or twice a week ensures that the programme can be improved and any problems can be addressed. It is always nice to meet away from the pool environment to ensure everyone is relaxed and no-one feels that they are in “your territory”, which would perhaps prevent people from speaking up.

Each coach should be provided with time to air their opinions and, should consider the following:

Swimmer progress – providing a summary of how they feel the swimmers are responding to the programme, training progress, attendance and behaviour;
Self and peer evaluation – feedback to other fellow coaches on their strengths and weaknesses. Evaluate one’s own performance;
Programme evaluation – discuss how well they feel the training is going, suggesting ways to improve it and express any other points regarding the programme.

Coach meetings can also be used to highlight upcoming competitions, and discuss who will be swimming which events, coach cover for the meet, and, strategies that will be encouraged. You may also wish to consider which meets the swimmers should target next. Debriefing after a competition is essential in improving the programme. Everyone involved should detail the positives and negatives of the meet and what actions they should take to improve on the next competition.

The one danger of coach meetings is that they become political; avoid this at all cost. The coaching meeting should be used to discuss the progress of the swimmers and the training programmes. Remember what you are there for – the swimmers.

I hope this provided a useful guide for any coaches involved in youth swimmer and indeed of any age, feed-back is always appreciated – critical and positive. Please don’t hesitate to ave any questions and I will do my upmost to answer them – either via WordPress comments or twitter.

Yours in Swimming,

SwimCoachStu

Streamlining and Submarines

Reducing resistance in a swimmer should be a top technical priority for all coaches, taking precedence before any changes to improve propulsion. Although, the former will have the consequence of improving the latter. The most fundamental way to reduce drag is through streamlining. A streamlined body is one which is horizontal in the water – this includes the head and body; the flatter, the less resistance created.

– Streamlined swimmer = greater velocity and distance per stroke.

Submarines

Let’s start with an analogy to highlight this point. Take a submarine on the surface of the water; no need to imagine it, here is a picture:

20140225-151632.jpg

Here you see the front of the submarine minimally disturbing the water, in fact, it is slightly underwater. Now take a look at the structure protruding from the submarine; here you see a great amount of drag being created – evident from the white water.

Frontcrawl

This white water effect occurs similarly (not to such a scale of course) from the head of a swimmer breaking the surface of the water. Ideally, the frontcrawl stroke needs to replicate the front of the ‘sub’. Here are the instruction points which should be communicated to the swimmer in order to achieve this position:

– Look directly down at the bottom of the pool;
– The tip of the swimmers’ buttocks should be at a level height to that of the top of the swimmer’s head;
– There should be some water which travels over the swimmer’s cap.

Backstroke

These principles are much the same in the case of backstroke, apart from the obvious difference.

– Head should be back, looking up at the ceiling;
– Water should travel over the face;
– Both ears should be submerged;
– Top of hips will be in line with the top of chest and face.

Breaststroke and Butterfly

During breaststroke and butterfly, it is not possible to remain in a streamlined position at all times; however, it is important to continue in the latter position for as long as possible. When a breath is needed, the athlete should be trained in movements which will cause the least amount of disruption to the water.

Firstly, butterfly. There are two main factors in the stroke which should be considered:

– Increasing size of kick = increased resistance:

Bigger kicks tend to cause greater movement at the hips, which both create a fairly slow kick rate; this reduces the opportunities to initiate a propulsive action. The increased drag eventually outweighs any propulsion.

– Increase in vertical height = increase in resistance:

Frontal resistance is substantially increased when a swimmer’s head and shoulders are lifted vertically out of the water, whether he/she is breathing or not. There is also the added resistance which comes from the swimmer returning from this high position and often ‘slaps’ down on the water.

A ‘see-saw’ movement is observed in many swimmers. They drive their head and shoulders down into the water, the hips lift as a consequence, and the feet kick down. The swimmer expends a significant amount of energy swimming like this. This movement is also caused by an arm recovery which travels, unnecessarily, high on exit.

In butterfly, to create an optimal streamlined position, the following points should be adhered to:

– Breathing should be low and forward;
– Reduce the vertical movements of the arm entry, exit and the kick where possible;
– Keep the body in a streamlined position for as long as possible.

In breaststroke, the breathing action very much determines the amount of streamlining which is achieved. A ‘see-saw’ is sometimes also seen in the breaststroke. The points below, govern what breaststroke technical points should be followed to achieve the most streamlined position possible; which are almost identical to the fly stroke:

– Breathing should be low and forward;
– Any ‘see-saw’ movements should be completely discouraged – this includes downward movement of arm or raising of hips;
– Keep the body in a streamlined position for as long as possible.

If changes in other elements such as arm action, kick or breathing are required to improve streamlining, these should be instructed separately, not all at once.

Improvements can be verified through stroke counting, as improved streamlining should account for greater distance per stroke.

A final point to make is that all these instructions should be conducted at race-pace velocities as soon, after the movement has been established at less-than-race-pace speeds, as possible. Technique is closely related to velocity. Technique at slow speeds will unlikely be reproduced at race-pace.

Yours in Swimming,

SwimCoachStu

The Body in Swimming: Training the ATP-CP system REVISED

Previously in my ‘The Body in Swimming’ series, I wrote a description of the Adenosine triphosphate-creatine phosphate (ATP-CP) energy system. In this post, I would like to revise some of the descriptions I made and also, would like to include a component of stored energy I have not initially mentioned which is recognised as playing a significant role in energy provision of swimming events over recent years.

Firstly, I would like to remind you about the comments made regarding the duration of the ATP-CP system i.e. how long it could sustain energy production. In the previous article is was stated that “Although the rebuild process can be completed extremely fast, the drawback is that is can only be used for approximately 4-5 seconds of max effort (di Prampero 1971). Therefore, a maximum rate of muscular contraction can only last for 4 to 6 secs.” Since writing the article, I have delved further into the evidence and have come to conclude that the above statement (and previous article) was wrongly generalised i.e. compared to other sports rather than specific to swimming. There are some factors which were not included, and their implications have caused me to revise the description.

Understating the ATP-CP system

It was concluded in the previous post that “time would be better spent developing other areas,” rather than dedicating training to seek improvements in the ATP-CP system alone. However, I feel I understated the importance of this system within a race and will set out to describe why I feel it is not an element that, in combination with another ‘stored’ energy source (which will be described below), should not be ignored.

Swimming, unlike various other sports, has a partially supported nature (totally supported in open water swimming), through the forces the body is acted upon in the water. As the body does not require as much energy to ‘fight’ against gravity and maintain posture, it is wrong to generalise the duration of ATP-CP use across all sports. Since the traditionally determined time of 4-6 seconds concerned sports of an unsupported nature, it would be rightly suggested that in swimming this provision is of greater duration – which has been approximated at 10 seconds. Also of importance is the phenomenon which occurs in cyclic sports such as swimming i.e. a propulsive phase and recovery phase following occurs; which allows for restoration of some of the creatine-phosphate as parts of the body go through the recovery period in the stroke.

Stored Oxygen

The ‘stored’ energy source I referred to in the first paragraph is the stored oxygen within our muscles and circulation. Myoglobin present in the former and haemoglobin in the latter, are proteins which combine with oxygen and act as a readily available source of oxygen for the exertion of high-intensity. This stored oxygen source, in combination with the ATP-CP system, plays a significant role in energy provision of swimming events – which has not been previously recognised. Not only is it involved in the initial stages of exertion, but it is also partially restored during recovery phases of a swimming stroke – as with the ATP-CP system.

Fast-Component of the Aerobic System

To understand the importance of the ATP-CP, in combination with the stored oxygen capacity, knowledge of the ‘fast-component’ of the aerobic system is necessary. This area of the aerobic system involves the restoration of the two named systems during and after swimming exercise. The partial recovery phenomenon has already been discussed. Complete recovery of the ATP-CP and stored oxygen occurs after approximately 30 seconds post total-body exercise – even if different parts of the body have experienced different intensities.

Recent research has endeavoured to identify the importance of this fast component (during and after total-body exercise). In 2009, Alves et al., found that only VO2 max and the fast component correlated with 400m performance; Reis et al., also found this similar result. Fernandes et al. (2010) showed that only the fast component was related to performance in 200m performance. Thus, the ability to restore the ATP-CP and stored oxygen – partially, during exercise and completely, post exercise – is directly related to performance up to 400m. Due to the similarities in aerobic and anaerobic use in the 400, 800 and 1500m events, it can be hypothesised that this component is also significant at these distances; however, further research is required to confirm this.

The implication of the above is that traditional training, which does not adapt to the fast component of the aerobic system, is ineffective in optimally improving performance. Indeed, this is substantial justification for a completely different emphasis in competitive swim training programmes.

Revised Conclusion

To conclude, this article has revised the previously generalised and incomplete knowledge of the ATP-CP system and has provided an explanation for greater emphasis on training which will adapt the fast component recovery of the aerobic system i.e. restoration of stored oxygen and ATP-CP.

It is suggested in this article that traditionally emphasised training of the lactate system is wrongly placed in improving performance and I will ensure my next article delves into this further. I will also attempt in the future to discuss training methods which aim to improve this fast component and identify the other important energy provisions in a swimming race.

Yours in Swimming,

SwimCoachStu

Belief-based Vs Evidence-based Coaching

Hello to all my loyal and new readers,

Firstly, I would like to apologise for my recent absence, I have been busy experiencing a coaching epiphany of somewhat, of which I shall explain below; as well as being buried in my coursework. I would also like to mention that in this post, I will not be focusing on my series regarding the ‘Body in Swimming’, which I hope to return to soon. Instead I am going to try and convince some of you to rethink the way you coach – something I am finding to be a rather bold and daunting task.

Belief-based coaching

How much of what you coach or train swimmers by, do you know is based on scientific evidence? How did you come about concluding that what you are preaching is the right way of doing things?

Belief-based coaching includes the use of personal experiences, in that, it worked for some swimmers so it must, therefore, work for the rest (especially if those swimmers are your ‘top’ performing swimmers). This reasoning is concluded from trusting the knowledge you have acquired is reliable and, from using your interpretations of what you have read or heard from other coaches – in particular, ‘senior’ coaches. If a coach’s methods are shown to have not worked, then the blame will be placed on the athlete, i.e. the swimmer did something wrong to have produced the unexpected performance – rather than it being the coach’s training method to be at fault.

Unfortunately, belief-based coaching plagues many swimming organisations. The training is not based on accurate sports science or scientific evidence. It is, as Brent Rushall describes it, “subjective, biased, unstructured and mostly lacking in accountability.”

I am as guilty as most coaches for applying training methods based on my own interpretations e.g. Instruction from other coaches and following ‘what everyone else does’. This is not the way we should be coaching swimmers; instead, we should be applying methods of training based on evidence.

Evidence-based coaching

Evidence-based coaching relies on scientific studies and research as the basis for training. Rushall, a champion of evidence-based coaching, describes how coaching principles should be decided from: “several independent published scientific studies that report similar findings about human behaviour and therefore, deemed to be of substantive and reliable merit.”

Evidence-based coaching principles also allow for training effects to be reliably predicted, tested and verified – this is something which is uncommon in belief-based coaching. The latter camp often argues that it is tough to predict/measure certain effects/results and often hide behind this – blaming errors on uncontrollable factors rather than their practices.

A Vicious Cycle

The problem with many swimming organisations is that many refuse to receive evidence that may change their beliefs and structure. They then continue to feed incorrect knowledge to their various members (clubs/districts/regions) who then apply these belief-based methods.

These organisations often defend their beliefs by pointing out the successes of their athletes. However, as described before this is the problem with belief-based coaching – they wrongly support their methods using the observations of a few; again allowing for the spread of error throughout the organisation.

An important phrase to note is “the few.” Although belief-based methods may work for some swimmers, many athletes are left behind. They often conclude that the reason why some swimmers don’t perform well is simply that “they haven’t got it”; this is a ridiculous notion.

Out-dated

Many myths exist in swimming that are very long-standing and, are mainly due to individuals and organisations not scrutinising their knowledge. Up to 20% of what we learn today will be inaccurate in one years time; this percentage only increases with relation to years.

Ignorance should not be an excuse. It should be seen by all coaches and organisations as their responsibility to ensure that they evaluate their practices, seek to analyse their knowledge and use evidence as the basis of their sessions.

It is easy to appreciate why many individuals follow the beliefs of their organisations rather than attempt to dispute, analyse or evaluate it through the use of research. Extracting information from scientific research, studies and, papers, is a skill that many coaches do not currently possess. Those responsible for educating coaches should ensure that they 1) encourage the use of evidence-based coaching 2) provide coaches with the skills to apply it.

It’s Down to You

I hope a few of you that read this article will realise the dangers of belief-based coaching and will look to employ evidence-based.

It can be tough to take the jump from belief-based to evidence-based coaching; however, It is every coaches responsibility to ensure that they use evidence and science for choosing, developing, and justifying a training strategy in order to give swimmers the best possible chance of achieving their potential.

Yours in Swimming,

SwimCoachStu

Please note SwimCoachStu posts are all of my  own opinion and are not necessarily endorsed by other clubs or organisations which I may be affiliated to

A brilliant resource for the evidence-based coaching approach can be found Swimming Science Journal

I would like to thank a fellow evidence-based champion for inspiring me to write this.

References:

Rushall. B. S (October 2003) Coaching Development and the Second Law of Thermodynamics (or Belief-Based Versus Evidence-Based Coaching Development [Online] San Diego University

Sprint Swimming: A Different Take

Introduction

There are many coaches who refuse to accept many of the science which is published regarding swimming – no topic more so than sprint swimming. I for a long time was one of them; believing that you could prescribe endurance training – developing the swimmer’s aerobic base, as well as expecting those athletes to develop their speed (for 50m events) by initiating sprint sets a few times a week. As described in my earlier articles, anaerobic metabolism is hindered by endurance training (see SwimCoachStu – Anaerobic metabolism ), therefore, mixing the two (sprint and endurance training) is a contradictory idea.

Out-dated Thinking

There has been a relatively small number of top level sprint swimmers, in the past and present, this has been contributed to the idea that these swimmers have been the ‘lucky’ ones rather than claiming their success is due to their coaching. Many sprinters have been wrongly involved in programmes which have declined their ability to perform in the 50 metre events and are often including amongst those training for greater distances. Coaches have excused this by providing those sprint swimmers with a break between training and competition, however, this only returns their speed to an innate level – that is, if they receive a long enough taper – rather than any improved sprint ability.

The most common mistake in developing sprinters, is coaches using sprint sets constructed of repeated 25 and 50 metre distances, with the idea that swimmers will be forced to work through high-levels of fatigue to some how seek physiological improvements in the swimmer. Further to this, common practice has been to finish off a training session with ‘sprints’. Both of these are physiologically wrong because the body is unable to tax the capacities required for increasing speed when under these stressed and fatigued states.

Neural Function in Sprinting

Although, the above paragraph describes the detrimental effects on the body physiology, there is a more important element to consider – neural function. Speed improvements are primarily neural rather than physiological. What implications does this have on how we train sprinters?

Well firstly, coaches training 50m swimmers must ensure they create programmes in which neuromuscular patterning, i.e. skill takes great precedence. It has commonly been asserted that if skills are to be performed when an athlete is tired, then learning those skills whilst fatigued is the best procedure. However, this practice in fact inhibits the formation of neuromuscular patterns due to the increase of acid within the supporting physiological environment – making it very difficult, or indeed impossible to learn skills. Despite the evidence, many coaches still accuse those with this view of committing blasphemy! Skill acquisition should not be performed under the same physical stress as experienced in a race, however, it should be undertaken at desired race speeds. An efficient sprint performance depends largely on the number of times the skill is performed at the goal pace.

The current way of developing sprinters, by many, is neither allowing for increases in speed nor allowing for any great skill attainment. This turns us to the question of, how do we accommodate for both quality (technique) and quantity (physical adaptation)?

Ultra Short Training

A solution to this comes in the form of training at distances shorter than the conventional 25 m sprint distance, therefore, less duration of work and with a reduced work-to-rest ratio – known as ultra short repeats. It generally consists of a large number of repeats, allowing for a large volume of race pace training (rests of no more than 20 seconds), and with the advantage of its aerobic nature it prevents any significant volumes of lactic acid building as well as allowing for significantly quicker recovery.

This form of training, when performed over a substantial duration, e.g. 30 mins produces various conditioning effects such as improvements in the anaerobic system, the aerobic system and increased functional strength. Although “Ultra-short work does not produce as rapid lactic acid adaptation, it eventually does produce higher levels of glycolytic adaptation and consequently produces further performance improvements” than compared to typical, ‘heavier’ sprint training.

One of the most important outcomes from this training is the ability to build race-specific neuromuscular patterns under non-fatigued conditions. Ultra short training should be used as the main type of training for 50m sprint swimmers, performed as early in the session as possible (after warm up and low intensity technical development).

A comparison of ultra short distance training and traditional training can be found at the Swimming Science Bulletin

Child Sprinters

A controversial subject is allowing prepubescent children or adolescents to specialise in sprint training until they reach a certain age. Before the age of approx. 14 y.o. for boys/ 13 y.o. for girls a child’s aerobic capacity is at a critical stage and later this window of opportunity will close forever – many claim that sprint training cannot provide this necessity. However, I argue that a sprint programme containing ultra-short distance training provides children with this aerobic exercise.

I also believe sprint programmes provide the opportunity for children to pursue other activities outside swimming if they so wish due to the reduced hours required, compared with those training at greater distances – this also allows children to develop their aerobic capacity in other ways.

The final disagreement is that children do not develop the technical base, which is required for progression in the sport, with sprint training. To counter that point simple read what is described above; technique is central to sprinting!

Big Changes

The current set up in the majority of clubs for training sprint swimmers is, in my opinion, fundamentally wrong; and for that matter, some clubs do not accommodate at all for sprint swimming. Clubs should, where possible, provide a separate programme for all those athletes who wish to focus on 50m events just as they do for middle/ long distance swimmers and as they do for different age groups.

Change is required in the negative hype surrounding sprint training, particularly about children sprinting. All ages should be allowed to enjoy swimming in which ever form they choose and clubs should look to accommodate that wherever possible.

Yours in Swimming,

SwimCoachStu

I would like to stress that all of my articles are of my own opinion and should not be associated with any other organisation. I also do not claim to be an expert in sprinting and have based my opinion on various experience and sources (I in fact prefer coaching longer distances!)

Rushall, Brent S. An ignored scientific component of sprint swimming, [Online], Available: http://coachsci.sdsu.edu/swim/bullets/ultra28.htm [26 October 2013]