1 A COACH S MANUAL HYDRATION FOR PEAK PERFORMANCE Produced in conjunction with: Sally Walker, APD Sports Dietitian, NSWIS Kenneth Graham, Principal Scientist, NSWIS
2 FLUID Focusing on adequate hydration doesn t come naturally for most athletes. There is no one size fits all fluid plan. Requirements can vary greatly between athletes based on many variables such as, sweat rate and training conditions. That s why we ve developed this manual to help you include hydration as a key part of performance training. As the team Athletes coach, we focus know so it s much important of their for time you and to be effort armed in training with useful to improve information, performance hd hydration strategies and physical and tips and that mental are strength based on for sound competition. evidence What and easy is often to not put top into of practice. mind is the value of balanced nutrition and hydration it can be the difference between good performance and peak performance during each training session as well as on game day. FACTOR? THE FORGOTTEN PERFORMANCE Focusing on hydration doesn t come naturally for most athletes. There is no one size fits all fluid plan. Requirements can vary greatly between athletes based on many variables such as, sweat rate and training conditions. That s why we ve developed this manual to help you include hydration as a key part of performance training. As the team coach, we know it s important for you to be armed with useful information, hydration strategies and tips that are based on sound evidence and easy to put into practice.
3 FUELLING OPTIMAL PERFOMANCE Huge demands are placed on the body through specific and detailed training programs where athletes push themselves to reach their peak strength and performance. To maximise each training session, our bodies need the right type of fluid, fuel and nutrients to: Perform at their best Recover effectively from training stresses Carbohydrates fuelling performance To fuel the body for activity and growth, carbohydrates are the best source of energy for both the muscles and the brain. When foods containing carbohydrates like bread and breakfast cereals are digested, they are broken down to release glucose for transport in the bloodstream. In training, glucose can be used immediately as the primary fuel source for exercising muscles and stimulating the central nervous system. Isotonic sport beverages like POWERADE Isotonic provide carbohydrates for rapid absorption and thus deliver glucose into the bloodstream for use by muscles and organs. POWER FACT WARNING SIGNS THAT THE BODY S CARB RESERVES ARE RUNNING LOW INCLUDE: FATIGUE AND LETHARGY, LOSS OF FOCUS AND CONCENTRATION AND DECLINING PERFORMANCE
4 No carbs, no energy for muscles... When carbohydrate stores run out and aren t topped up, performance quickly declines and fatigue sets in. Warning signs that the body s reserves of carbs are running low include: Fatigue and lethargy Loss of focus and concentration Declining performance Fluids hydrating for performance In addition to carbs, we know that fluid replacement is a key priority during training and competition as even mild dehydration can impair athletic performance - a mere 2% reduction in body weight as a result of fluid lost during activity has been shown to have negative effects on performance 1. Once you ve noticed an athlete s performance suffering, it s hard to undo the damage. That s why it s critical to implement strategies to prevent or delay dehydration during training sessions and competition. Your athletes will perform and recover more consistently if well hydrated. POWER FACT NEGATIVE EFFECTS ON PERFORMANCE HAVE BEEN SHOWN WITHIN JUST 2% REDUCTION IN BODY WEIGHT AS A RESULT OF FLUID LOST DURING ACTIVITY
5 HOW DEHYDRATION AFFECTS PERFORMANCE As our bodies are made up of around 60% water present both in and around cells including muscles and blood vessels - dehydration can cause significant effects on performance. WHAT HAPPENS WHEN AN ATHLETE IS DEHYDRATED Muscle fatigue Active muscle cells become fatigued and lose strength Decreased muscle growth and repair post training = reduced potential strength gains 2 Blood flow and circulation changes Blood volume decreases = the heart has to pump a smaller volume of blood to working muscles making the heart work harder and increasing heart rate The loss of fluid may increase blood viscosity and increase the load on the heart and circulatory system 3 Reduced mental function Lowered blood sugar to the brain causing a drop in concentration, focus Impact on movement patterns and skill levels in team sports such as rugby, AFL and football Feeling dizzy, flat or fatigued 4 Increased body temperature Fluid is critical for cooling the body down when it is hot. Dehydration can reduce sweating and cause body temperature to rise and lead to premature exhaustion
6 HOW DO I MONITOR HYDRATION STATUS? Fluid requirements vary widely from athlete to athlete and can be influenced by body size, weather (heat, humidity), exercise intensity and fitness level of athlete. So, it s important to coach each athlete on their individual hydration status and fluid needs. With your athletes training regularly, it s good to outline a few signs and signals they should be aware of to get an indication of their own hydration status. Any of these three signs indicate hydration status needs to be investigated: General feeling of tiredness and fatigue Dry eyes Dry mouth POWER FACT BEWARE OF THE - GENERAL FEELING OF TIREDNESS AND FATIGUE, DRY EYES OR DRY MOUTH. EARLY SIGNS OF DEHYDRATION
7 Three hydration tests If you are concerned about any of your athletes hydration status, you can investigate by using one of the following methods: 1 1. Monitoring body weight to estimate fluid requirements Weigh immediately before and after training sessions to find out the amount of fluid lost during activity. Each kilogram (kg) of weight loss is approximately equivalent to one litre (L) of fluid. This amount can be used as a guide to determine how much athletes lose in a session and to plan pre activity hydration guidelines so athletes have this fluid to lose. If body weight continually drops over a week of training, fluid stores may not be getting adequately replaced after each session. To get an idea of how much fluid your players need to consume during a given session of training, log onto the hydration calculator at Weight change during a training session reflects your total fluid loss - the difference between your sweat losses and fluid intake. Before Training Body Weight 70kg After Training Body Weight 69kg Fluid/Sweat Loss approx 70kg 69kg = 1L Fluid/ Sweat Loss 2 2. Urine colour and flow easy and cost effective If there is a long period without needing to urinate or a small volume of urine produced there may not be adequate fluid loads. The colour of the urine can also show the concentration of urine - if it is darker you may be dehydrated, lighter urine towards clear can indicate good hydration. Outline to athletes that they should observe urine output over the course of a day and notice changes in urine flow and colour. Output volume and frequency should be consistent and the colour should be getting lighter towards the end of the day, aiming for the last outputs of the day being close to clear Urine specific gravity (USG) This is a scientific measure of hydration conducted by measuring the density (concentration) of a urine sample. Tests such as this one are useful but will require some equipment. A sports dietitian Vitamin supplements may darken the urine colour. Thus if your athletes are taking vitamin supplements this test may be unreliable. Urine Colour Chart Urine Colour Chart has been adapted from Armstrong. Colour rating of 1, 2 or 3 is considered well-hydrated although certain medicines and vitamins may cause the colour of the urine to change, making this test unreliable. or physiologist may be able to help you identify where this will be available and how to use it. USG findings: 1.01 = Hydrated; Up to 1.03 = Severe/Extreme Dehydration
8 TRAINING AND EXERCISE SESSIONS IMPACT ON HYDRATION In a neutral environment, the body manages fluid levels through a physiological mechanism of balancing fluid intake through thirst, and output through urine and sweat. During training, these mechanisms do not work as effectively, heat and sweat production are increased and urine production is decreased. When fluid is being lost through sweat at a rapid rate, the thirst mechanism may not be sufficient enough to encourage an adequate level of fluid consumption to prevent dehydration. In intense training sessions, athletes should not rely solely on thirst as a cue to consume more fluid. This can be a problem for athletes training twice a day - they may not have fully rehydrated from the first session before going into the next session, hence they re already dehydrated and may not be at an optimal level of hydration for training.
9 MANAGING SWEAT LOSS FOR ADEQUATE HYDRATION WHAT SWEAT CAN TELL YOU During high levels of activity, it is possible for some athletes to lose between 0.5 2L/hour in sweat and fluid 5, particularly when training is conducted in hot and humid conditions. Sweat Loss = Body Fluid Loss You can monitor your athletes fluid loss by weighing each individual directly before training or competition and then weighing them directly after. Always weigh each athlete with their full drink bottle before and weigh with bottle containing remaining fluids after. Any body weight losses will approximately equate to the amount of fluid lost: 1 kg loss in body weight = approximately 1L sweat/fluid loss Sweat Loss = Body Electrolyte Loss With high levels of sweating, the body also loses around 1000mg sodium and other electrolytes like potassium per litre of sweat lost 6. In very salty sweaters this sodium loss can be seen as white marks on a dark t-shirt. Replacing sodium is an important part of rehydration as it allows the body to retain fluid consumed, as well as maintaining blood volume, sweat rate and muscle blood flow. POWER FACT DURING HIGH LEVELS OF ACTIVITY, ATHLETES CAN LOSE BETWEEN 0.5-2L/HOUR IN SWEAT AND FLUID, PARTICULARLY IN HOT AND HUMID CONDITIONS
10 FLUID GUIDELINES HOW MUCH, WHAT TYPE AND WHEN? There is no one size fits all fluid plan for athletes. Fluid requirements vary between athletes and within each athlete based on exercise intensity, sweat rate, training or competition environment and conditions e.g. heat and humidity. How much fluid and when? The table 1,7,8 below provides a guide only and needs to be individualised based on tracking of each athlete s hydration status after training sessions and competition. Activity Timing (training, competition) Before Activity Fluid Needs 10ml/kg body weight up to 2 hours before During Activity ml every 15 minutes Post Activity 150% of amount of fluid lost during activity* *Remember: 1 kg weight loss = approximately 1L sweat/fluid loss. POWER FACT THERE IS NO ONE SIZE FITS ALL FLUID PLAN FOR ATHLETES. FLUID REQUIREMENTS VERY BETWEEN ATHLETES AND WITHIN EACH ATHLETE BASED ON EXERCISE INTENSITY, SWEAT RATE, TRAINING OR COMPETITION AND ENVIRONMENTAL CONDITIONS E.G. HEAT AND HUMIDITY
11 WHAT SHOULD ATHLETES DRINK AND WHEN? HIGH INTENSE EXERCISE Short (< 60 min) PRE-ACTIVITY water OR Duration Long/ Endurance (> 60 min) DURING ACTIVITY PRE-ACTIVITY DURING ACTIVITY water + For low intensity exercise water may be sufficient, however if the session lasts for over 60 minutes, POWERADE Isotonic may be more appropriate. CAN YOU DRINK TOO MUCH? Whilst remaining well hydrated is key to feeling great and performing at your best, you need to be careful not to drink too much, or over-hydrate. Overhydrating with water or low sodium drinks can result in hyponatraemia, or low sodium levels in the blood. The symptoms of hyponatraemia can be similar to dehydration headaches, disorientation, nausea and vomiting. Most reports of hyponatraemia have occurred in ultra-endurance running events (often greater than six to eight hours), with those most at risk being slower runners with plenty of opportunity to drink. The main issue is to not drink so much that you gain weight during your event.
12 WHAT IS ISOTONIC AND WHY IS IT IMPORTANT? Isotonicity is all about balance. Our bodies perform best when there is a balance between the substances inside the cells in the bloodstream and outside the cell membranes. These substances include electrolytes (sodium and potassium) and fluids. If a fluid is isotonic like POWERADE Isotonic, it has been specially developed to be in balance with the body s fluids. This means that when you ingest an isotonic fluid rather than say a juice or cordial, your body s water does not need to shift into your gut to dilute it. Instead, the fluid in POWERADE Isotonic is readily absorbed into the bloodstream for fast delivery of fluid and energy. PO POWER FACT IF FLUID IS ISOTONIC, IT IS IN BALANCE WITH THE BODY S FLUID WHICH MEANS IT WILL BE READILY ABSORBED IN THE GUT AND DELIVERED INTO THE BLOODSTREAM AND TO WORKING MUSCLES FASTER THAN DRINKS LIKE CORDIAL OR JUICE
13 POWERADE Isotonic: Scientifically Proven Fast & Effective Hydration POWERADE Isotonic has been scientifically developed to provide levels of sodium, potassium and carbohydrate to keep your body s fluids in balance and thereby improve hydration. POWERADE Isotonic Key Solutes Concentration of Key Solutes Carbohydrate 7.3% Sodium 12mmol/Litre Potassium 4mmol/Litre Consuming POWERADE Isotonic has been scientifically proven to help athletes perform at their peak for longer 9. This demonstrates that the combination of water, electrolytes and carbohydrates in POWERADE Isotonic helps improve exercise and performance ability. POWER FACT CONSUMING POWERADE ISOTONIC HAS BEEN SCIENTIFICALLY PROVEN TO HELP ATHLETES PERFORM AT THEIR PEAK FOR LONGER 9
14 COACH S CHECKLIST TRAINING AND COMPETITION DRINKING STRATEGIES GENERAL TIPS BEFORE ACTIVITY Key tips If you anticipate a long training session in the heat, provide a tub of POWERADE Isotonic for athletes to have during training as well as their water. Similarly, if a long session is planned, inform the athletes to consume water and or POWERADE Isotonic in the lead up to the session. Push the need to pre-hydrate adequately to meet fluid losses in training or competition: Within 2 hours of going to bed or prior to competition consume fluid at 10mls/kg body weight. For example, 600mls for a 60kg athlete. If the session will be prolonged and intense or if it will take place in a hot/humid environment, POWERADE Isotonic could be used in the same amount. Immediately before training or competition, each athlete needs to weigh themselves with their drink bottle and record their starting weight. Having an idea of individual athletes sweat/weight loss in each session helps to target athletes that might need more attention with pre-hydration and provide an amount which they should consume before training. Make sure players have access to water or drinking facilities and that drink bottles are full before training starts. Observe athletes who arrive at training without a drink bottle or rarely have one as these players may need closer intervention on their drinking habits.
15 DURING ACTIVITY Key tips Provide drink breaks at least every 15 minutes where possible and outline that players should consume towards ml at each of these breaks. Encourage consuming water rather than swishing it around the mouth and spitting it out and pouring over the head. These may cool the body but will not hydrate. Make sure drink bottles are in an accessible range during training and if going off site either take them with you or ensure there is a water station where you will be. Observe players who may not participate in the drinks breaks or appear to not drink regularly. If activity is longer than 60 minutes or in a hot environment which would induce high sweating rates, provide POWERADE Isotonic for consumption at every second drinks break during the session. POST ACTIVITY Key tips Record weights of athletes post training to identify fluid losses and sweat rates. This information will be beneficial to educate athletes on how much to drink prior to the next session. Replace fluid losses by 150% over the first few hours following training to account for ongoing sweat and urinary losses 1. Best choices for rehydration: water, sports drinks like POWERADE Isotonic and even low fat milk.
16 Example: Post Training Rehydration 15 year old rugby league player -Field training session in 28 C (80% humidity) for 1.5 hours Weight before training session with full water bottle: Weight after training session with water bottle: Weight loss: 75.0kg 73.8kg 1.2kg Rehydration fluid needs: 1.2 x 150/100 (1.5) = 1.8 L of fluid to drink over the next few hours
17 REFERENCES 1. Sawka M.N., Burke L.M., Eichner E.R., Maughan R.J., Montain S.J., Stachenfeld N.S. (2007) ACSM Position Stand - Exercise and Fluid Replacement. Med. Sci. Sports Exerc. 39: Judelson, D. Maresh, C. Yamamoto, L. Farrell, M. Armstrong, L. Kraemer, W. Volek, J. Spiering, B. Casa, D. Anderson, J. (2008) Effect of hydration state on resistance exercise-induced endocrine markers of anabolism, catabolism and metabolism. J Appl Physiol. 105: El-Sayed, M.S., N. Ali, Z. El-Sayed Ali, (2005) Haemorheology in exercise and training. Sports Med,. 35(8): p Versey, N. O Connor, H. Brotherhood, J. Graham, K. (2006) Hydration and its assessment in athletes. Sports Nutrition. 17:(2), pp XIV-XVII. 5. Armstrong, L.E., Maresh, C.M., Castellani, J.W., Bereron, M.F., Kenefick, R.W., LaGassee, K.E., Riebe D. (1994) Urinary indices of hydration status. Int J Sport Nutr. ;4(3): Murray, B. (2007) Hydration and Physical Performance J. Am. Coll. Nutr. 26: (5) 542S- 548S. 7. AIS Sports Nutrition, Fluids Who needs it?, Australia Institute of Sport, July Fact Sheet, Fluid in Sport, Sports Dietitians Australia, May Graham, K. Marsden, J. Versey, N. Bourke, D. (2006) The effect of a carbohydrate-electrolyte sports drink on intense endurance exercise performance. The NSW Institute of Sport, Sydney Olympic Park, Australia. This POWERADE Coach s Manual is a guide only that contains advice of a general nature designed to assist you in assessing hydration needs for players engaging in training for basic team sports and athletic games. It provides summaries of the issues to be considered in assessing hydration needs, and an estimate only of the fluid requirements for average athletes in normal training conditions. Fluid loss and levels of fitness vary from person to person and will affect each athlete s fluid needs. Environmental conditions are also a significant factor in determining hydration requirements. Those who exercise in hot or intensive conditions, or who exercise at high levels of intensity for prolonged duration may need more fluids and should use their sweat rate to guide fluid intake. Coaches or players wishing to optimise their understanding of their own hydration requirements should take the professional advice of a sports dietitian or physiologist, rather than relying on the information provided in this manual. Note that POWERADE Isotonic contains carbohydrates and electrolytes in addition to the fluid, which can help to replace what has been lost through sweat and burned through exercise. Athletes and coaches should consider the additional ingredients in POWERADE Isotonic in the context of their total food consumption and their individual exercise and sporting needs The Coca-Cola Company. POWERADE and Mountain Blast are registered trade marks of The Coca-Cola Company.