Sport. Basketball (males) Training Competition. (summer training men) Ironman triathlon Bike Run

Transcription

1 Agenda Hydration Issues in Sport - Getting the Balance Right Richelle Flanagan BA, MSc, PgCert, MINDI SNIG co-ordinator richelle@nutritionwise.ie Fluid - the forgotten nutrient What types of fluids? What affects fluid intake? Develop a fluid plan Final word on alcohol Summary Fluid the forgotten nutrient We are made of water Humans contain L water Lost: sweat, urine, evaporation Water turn over varies between athletes Turnover increases during exercise & hot conditions Fluid the forgotten nutrient Effects of dehydration Impaired performance by 10-20% with ~2% of body weight Impaired mental function slowing reaction-response times decision making skills Increased risk of heat cramps, exhaustion & stroke >3% fluid losses Fluid the forgotten nutrient Fluid the forgotten nutrient Simple truth is that no other nutritional intervention comes close to providing the performance enhancing effects of staying well hydrated. Increased core temp sensed by brain Brain switches on sweat mechanisms Hot blood pumped to cooler skin Heat transferred into atmosphere Preventing dehydration:sports drinks or water Bob Murray, PhD, FACSM 1

2 What affects your sweat loss Environment Exercise duration & intensity Type of clothing/equipment worn Body size Fitness fitter sweat earlier and larger vol Genetics Heat acclimatisation Metabolic efficiency Sport Basketball (males) Training Competition Cross country run (summer training men) Ironman triathlon Bike Run Netball (females) Rowing Males Females Soccer Summer Training Winter Training Tennis Sweat rate mls/h 1370 ( ) 1600 ( ) 1770 ( ) 810 ( ) 1020 ( ) 980 ( ) 1980 ( ) 1390 ( ) 1460 ( ) 1130 ( ) 1600 ( ) Voluntary fluid intake (mls/h) 800 ( ) 1080 ( ) 570 (0-1300) 890 ( ) 630 ( ) 520 ( ) 960 ( ) 780 ( ) 650 ( ) 280 (30-630) 1100 Dehydration % Body Mass Change 1 (0-2.0) 0.9 ( ) kg (+3-1) 2 ( ) 0.9 ( ) 1.7 ( ) 1.2 (0-1.8) 1.62 ( ) 1.7 ( ) 1.3 Sport Sweat rate mls/h Voluntary fluid intake (mls/h) Dehydration % Body Mass Change Sure when I m thirsty I ll drink Basketball (males) Training Competition 1370 ( ) 1600 ( ) 800 ( ) 1080 ( ) 1 (0-2.0) 0.9 ( ) Thirst = poor indicator of need to drink Cross country run (summer training men) Ironman triathlon Bike Run Netball (females) Rowing Males Females 1770 ( ) 570 (0-1300) 810 One ( ) size 890 ( ) does 1020 ( ) 630 ( ) 980 ( ) 520 ( ) not fit all!! 1980 ( ) 960 ( ) 1390 ( ) 780 ( ) kg (+3-1) 2 ( ) 0.9 ( ) 1.7 ( ) 1.2 (0-1.8) Soccer Winter Training Summer Training 1460 ( ) 1130 ( ) 650 ( ) 280 (30-630) 1.62 ( ) 1.7 ( ) Tennis 1600 ( ) Ask yourself daily.. Am I thirsty? Is my morning urine dark yellow? Is my body weight noticeably lower this morning than yesterday morning Yes = most probably dehydrated How can I monitor my hydration? Daily Examination Use PEE chart as your guide 2

3 What colour is yours? Well hydrated Aim for 1-3 How can I monitor my hydration? Daily Examination Use PEE chart as your guide Hydration Monitoring Refractomer Very dehydrated How can I monitor my hydration? Daily Examination Use PEE chart as your guide Hydration Monitoring Refactomer Weight fluctuation Before & after exercise Fluid replacement during exercise ~ equal to sweat rate Athlete consumed 1L fluid during exercise but lost 1kg in weight from sweating Total sweat loss= Lost 2L Keep weight loss to 1kg or max 2% body weight Case study 1 Mark is a central forward Participates in a high intensity 90 minute soccer training session Pre-training weight = 75kg Drinks 1.5L during training Post-training weight = 73kg To avoid dehydration and overhydration, how much fluid should Mark consume during his next training session? Note measure weight before & after exercise in minimal clothing, towel dried Case study 1- solution Weight loss = 75-73kg = 2kg (~2L) % weight loss = 2/75kg= 2.7% (dehydrated) Total sweat loss = 2L weight loss + 1.5L drank during training = 3.5L Allowable sweat loss = 2% x 75kg= 1.5L Minimum fluid replacement = L = = 2L over 90 mins =~300mls per 15 minutes Maximum fluid replacement = 3.5L = 3L over 90 minutes = 450mls per 15 minutes Recommended Intake for Mark ~ mls/15min 3

4 Case study 2 Brian is also centre forward Participates in a high intensity 90 minute soccer training session Pre-training weight = 78kg Drinks 2.5L during training Post-training weight = 78kg To avoid dehydration and overhydration, how much fluid should Brian consume during his next training session? Case study 2- solution Weight loss = 78-78kg = 0kg % weight loss = 0kg =hydrated Total sweat loss = 0 weight loss + 2.5L drank during training = 2.5L Allowable sweat loss = 2% x 78kg= 1.5L Minimum fluid replacement = 2.5L 1.5L = 1L over 90 mins =~160mls per 15 minutes Maximum fluid replacement = 2.5L over 90 minutes = 410mls per 15 minutes Recommended Intake for Brian ~ mls/15min 1.5-2L per day Water Drink water if Exercise <30 minutes Low intensity exercise If high intensity > 30-60mins and cannot tolerate sports drinks need to take and sodium in another form 4

5 Water Water is a good thirst quencher but not always best re-hydrator Sports people who drink water drink less than they need lose more in the form of urine Water contains no flavour/electrolytes/ carbohydrates Sports Drinks Provide: Carbohydrate for extra energy Fluid for hydration Electrolytes e.g. sodium Choose according to requirement for: Fluid Carbohydrate Fluid and carbohydrate Electrolytes Sports Drinks Hypotonic <6g /100ml Want to replace more fluid than Sports Drinks - Hypotonic Per 100mls Hydro Active Active O2 (g/100mls) 2.0g 3.7g Sodium 40mg Can be beneficial in hot climate with little physical activity e.g. Sailing light winds/snooker/ Darts Sports Drinks Sports Drinks - Isotonic Hypotonic <6g /100ml Want to replace more fluid than Isotonic 6-8g /100ml Replace fluid and of equal importance Per 100mls (g/100mls) Sodium Lucozade sport 6.4g 50mg Gatorade 6.0g 49mg Club Energise 6.2 g 50mg Powerade 6.0g 50mg Can be beneficial in hot climate with little physical activity e.g. Sailing light winds/snooker/ Darts Generally most effective choice in most situations e.g. team sports, individual sports 5

6 Sports Drinks Sports Drinks - Hypertonic Hypotonic <6g /100ml Want to replace more fluid than Can be beneficial in hot climate with little physical activity e.g. Sailing light winds/snooker/ Darts Isotonic 6-8g /100ml Replacing fluid & of equal importance Generally most effective choice in most situations e.g. team sports, individual sports Hypertonic >8g /100ml Want to replace more than fluid Cold climates where dehydration is not a problem but large energy expenditure e.g. Cross country skiing, Mountaineering >8-10g/100ml may cause stomach trouble Per 100mls (g/100mls) Sodium BPM hydrate 15.3g 64mg Coca Cola 10.6g 0 Orange Juice 9.0g Note: avoid fizzy drinks as they will upset the stomach, many fizzy drinks do not enough sodium. 0 New Protein/ recovery drinks Evidence supports protein & taken Post strenuous training ~ Eat 70-90g carbs with 10-20g protein within 30 minutes of stopping exercise Per 500mls Protein Provon Revive 54g 18g Lucozade Recovery 54g 18g Milk 23g 17g Milk is a good option for a carbohydrate/protein drink after exercise. Ensure adequate fluid is taken with any powdered products. Always check with medical professional or Dietitian before taking any supplemental drinks. Anyone <18 years of age should avoid taking any supplemental drinks Sports Drinks Read the labels Per 100mls 28 kcals Trace g protein 6.4g 50mg sodium Niacin,Vit E,B6,B12, Pantothenic Acid.. Per 500mls bottle 140 kcals 0g Protein 32g 250mg sodium Niacin,Vit E,B6,B12, Pantothenic Acid.. Sports Drinks Read the labels Sports Drinks Read the labels Per 100mls Per 500mls bottle Per 100mls Per 500mls bottle 43 kcals 0.7g protein 9g 0 mg sodium Vitamin C, folic acid 215 kcals 3.5 g Protein 45 g 0 mg sodium Vitamin C, folic acid 10 kcals 0g protein 2g Trace mg sodium Niacin,Vit E,B6,B12, Pantothenic Acid, Ca 50 kcals 0g protein 10g 40 mg sodium Niacin,Vit E,B6,B12, Pantothenic Acid, Ca 6

7 Case Study 3 John enjoys a leisurely walk around his local lake most days of the week. The walk helps him to relax, keeps him moderately fit and helps to maintain his weight. It takes about 45 minutes. Case Study 3 Suitable Fluid: water Explanation: John s exercise session is low intensity. He is not trying to optimise his performance. Sweat losses are likely to be small. Case Study 4 Jane loves her daily sessions at the gym. She usually does about 1 hour, 6 days per week & includes a variety of strength and aerobic workouts. Most sessions are quite strenuous and she is dripping with sweat at the end. Jane has a snack before most sessions. She takes a water bottle with her but usually only has a few sips. Case Study 4 Suitable Fluid: hypotonic drink Explanation: Jane's sessions are moderately intense. She has a snack prior to exercise therefore does not need to consume additional carbohydrate during the sessions. A hypotonic drink may help Jane to increase her fluid intake. Case Study 5 Mary plays top-level hockey. She has 5 training sessions and 1-2 matches each week. Her training sessions are usually 2 hours and are often intense. She has to rush from work to training and usually only manages to eat a banana between lunch and training. Case Study 5 Suitable Fluid: isotonic drink Explanation: Mary s exercise sessions are long and intense. Her sweat losses and need for fuel during exercise are high. Mary's goal is to perform optimally at each training session. 7

8 What affects fluid intake? Athletes awareness of their sweat losses Awareness of disadvantages of dehydration Dislikes taste/sensation Availability of fluid Stomach comfort What affects fluid intake? Athletes awareness of their sweat losses Awareness of disadvantages of dehydration Dislikes taste/sensation Availability of fluid Stomach comfort Fear of weight gain Fear of need to urinate during exercise Lack of practice What affects fluid intake? No fluid available at venue Hard to carry fluid while on the move Don t like taste of sports drink Forget to drink during training Don t know how much to drink Stomach clenches before event & can t drink Take own filled bottle Plan drink stops Use backpack Trial different ones Dilute 50:50 Plan breaks Set watch Do fluid balance check during training & events Sip fluids over 2 hours prior to event Case study 6 Seán is a GAA half back Experiences heavy legs for the first 15 minutes every time he starts a game He drinks an mls of Isotonic drink in the 2 hours prior to the games Case Study 6 - solution Seán may be experiencing rebound hypoglycaemia May be due to taking too much isotonic fluid prior to his games Swap isotonic fluids for water or hypotonic drinks in the 1-2 hour prior to the game Do few quick short sprints before going onto pitch 8

9 Develop a fluid plan Not about drinking all around Individualise Practicing throughout pre-season and in season Look at fluid intake pre, during and post exercise Understand sports dynamics Rest breaks/time outs Fluid accessibility Develop a fluid plan Anticipate different conditions Tournaments versus one off events Hydration between bouts High temperature Uniform/clothing effects High humidity Indoor sports Uniform/clothing effects Low air movement Uniform/clothing effects Bright sun Dark colored clothing Develop a fluid plan IAAF 2007 consensus thoughtless following of general recommendations of the volumes of fluid consumed should be discouraged, as it is so easy for athletes to assess their own drinking requirements to ensure hydration pre-exercise Well hydrated before exercise drink fluids regularly throughout the day leading up to training/event Have drink with meals and snacks Fluid choice Any fluid during the day to make up 2L and meet requirements Isotonic/Hypotonic/water in 1-2h prior to training/event pre-exercise Deficit during 1 session can compromise next session if fluid not replaced Body weight should be relatively consistent across exercise sessions Keep track fluid losses pre-exercise Stomach priming Extra volume of fluid just before event can extend stomach -> increase delivery of fluid to the body Most athletes tolerate ml immediately before event Limited research papers Can be of use for athletes who have problems accessing fluid during exercise 9

10 pre-exercise Fluid Recommendations ACSM advises ml water 2h prior to exercise Sprint/middle distance/distance/multi-event athletes 500ml bolus containing Na or taken with Na containing food approx 2h before sprint Sprinters advised to euhydrate or at most be no more than 2-3% deficit prior to event Events where bodymass must be carried, watch for over-drinking during exercise Fluid choice Generally isotonic If cannot tolerate hypotonic/water & food mls every minutes as a guide but really should match individual athletes sweat loss Depends on practicalities of your sport Practice fluid replacement plan in training after exercise Fluid choice Generally Isotonic If cannot tolerate then hypotonic/water plus foods with salt 1 kg body weight lost = 1L fluid loss Aim to drink 1.5 x fluid loss over 2-4hrs after event after exercise >2L deficit or >2-3% BW lost Add salt to post event meals/snacks Salty snacks, Sports drinks Develop a fluid plan Alcohol Hyponatraemia ultra endurance events Common Causes excessive fluid consumption excessive sodium loss in sweat excessive sweating salty sweaters Risk Factors heat stress environment long duration slower athletes non-acclimatized athletes small body weight (females) Empty calories Makes you pee Depletes vitamin and mineral stores Cause stomach ulcers Destroys brain and liver cells Delays injured muscle recovery There is NO upside to drinking alcohol for athletes!! 10

11 Summary Fluid the unforgotten nutrient Check your fluid balance What types of fluids? Choose right drink for you according to training, event, your stomach What affects fluid intake? Identify what is going to affect your fluid intake Develop a fluid plan Write your own plan PRACTICE 11