Performance Nutrition for Cycling Nanna L. Meyer Sport Dietitian, Professor, Healthy Campus Nutritionist University of Colorado, Colorado Springs

Transcription

1 Common Nutritional Issues Performance Nutrition for Cycling Nanna L. Meyer Sport Dietitian, Professor, Healthy Campus Nutritionist University of Colorado, Colorado Springs High Energy Demands Energy and carbohydrate Fueling during training/competition Recovery Energy Deficiency in Sport Health & performance consequences Treatment strategies No start criteria Other Nutrition Issues Iron Status Dietary/Sport Supplements Periodization of Eating Energy Expenditure Variability Throughout The Week Rest/Off Easy Days Moderate Days Intense Days Competition Recovery Changes must occur Energy intake Carbohydrate intake Protein intake Fat intake Workout Foods/s Dietary Supplements Training Macrocycle, Mesocycle, Microcycle EASY ~500 kcal MEDIUM ~800 kcal PREP RECOVERY PREP HARDER > 1000 kcal MED HARDER EASY Training Volume/Intensity; Environmental Factors Problematic Approaches Carbohydrates: Effects on Muscle Glycogen Extreme energy restriction, skipping meals, sleeping through recovery, extra training outside of plan, prolonged fasting, following fads Low carbohydrate intakes Low protein intakes Dietary supplements (e.g., energy drinks, ergogenics etc) Intense training w/ lack of recovery Energy Deficiency 6 (Costill, Miller. Int J Sports Med 1: 2-14, 1980) 6 1

2 High CHO During Intensified Training Results in Better Maintenance of Performance Achten et al High CHO during intensified training results in better maintenance of performance 11-day trial 10-day Wash-Out 11-day trial Decreased performance on low CHO diet Easy: 60 min at 75% HRmax Lab Trials: 30 58% VO2max; 30 77% VO2max, 8k Hard: maximal effort 16k Randomized, Cross-Over Diet Treatments High CHO: 8.5 g/kg/d Low CHO: 5.4 g/kg/d Achten et al

3 Current trends in manipulation of CHO availability and metabolism in sport Exercise / Diet Strategy Chronically low CHO: Chronic reduction in CHO availability, immune and CNS system effects, performance effects Twice a day training: Reduced CHO availability for 2 nd session from endogenous and exogenous sources, immune and CNS system effects, chronic performance effects Training after overnight fast: Reduced CHO availability from exogenous sources and reduced CHO availability from endogenous sources (previous intake), immune and CNS system effects, acute performance effects Burke, 2011 Current trends in manipulation of CHO availability and metabolism in sport Exercise / Diet Strategy Prolonged training with or without overnight fast and/or withholding CHO during session: Reduced exogenous CHO sources for muscle for session, acute reduction of CHO availability, immune and CNS system effects, acute performance effects Withholding CHO during first hrs of recovery: provides adequate fuel during session but may amplify post/exercise signaling due to short but targeted time of low CHO availability perhaps achieving training harder effect. Could interfere with refueling and readiness for next session. Should not be attempted if sessions are <8 hrs apart, immune, CNS, and acute & chronic performance effects Burke, 2011 Before, During, and After Exercise Athletes Need More Protein than Nonathletes! é Protein turnover in athletes Protein breakdown Protein synthesis é Need for protein Exercise é synthesis and breakdown Protein intake é synthesis, ê breakdown è Synergistic effect: é Net balance Timing and Amount g 5x per day Protein increases sa,ety and energy expenditure: Weight control Fat in Muscle: A Great Energy Source 2 hrs of submaximal cycling depleted muscular fats by 50% in trained cyclists and a low fat diet was unable to replete these fats within 48 hrs Eating before Training 2-4 hrs before Lunch Add on harder days. <60 min before Sports nutrition products or high carbohydrate snacks What s available? Average stores ~ 2-10 mmol/kg w.w. or estimated mixed muscle IMTG content of 0.2 kg (~1850 kcal) Drink ~ 2 cups of fluid Carbohydrate-rich Low fat, moderate protein Low in fiber What s available? Drink as preferred; if urine dark drink more! Carbohydrate-rich Low fat, little protein Low fiber 18 3

4 Carbohydrate Supplementation during Exercise Blood glucose during cycling at 74% VO2max (CHO vs PLA) Ingesting CHO during exercise > 45 min improves performance Delays fatigue/increases time to exhaustion Improves time-trial performance CHO oxidation during cycling at 74% VO2max (CHO vs PLA) Muscle Glycogen during cycling at 74% VO2max (CHO vs PLA) Effects of Mouth Rinse 2-3% performance improvement w/ 10 sec mouth rinse (glu or 12.5% time trial completion, repetitive ingestion Effect of nutritional status prior to mouth rinse most critical for effect Fasted or no food within 3-4 hrs prior to event Glucose Artificial Sweetener Applications Short duration exercise GI issues Weight control? Carter et al., 2004; Chambers et al., 2009; Rollo et al., 2008; Pottier et al., 2010, See Review by Painelli et al., 2011 Chambers et al

5 Carbohydrate Supplementation during Exercise CHO Oxidation Rates w/ Glucose and Fructose Active Transport Superior Endurance Performance with Ingestion of Multiple Transportable Carbohydrates Currell et al., 2008 Epithelial Cell Lumen Glucose Glucose SGLT Galactose Galactose Na Na + + AD P ATP Fructose Glut5 Na + K + K + Fructose Capillary Glucose Galactose Glut2 Glut2 Fructose Subjects: 8 trained male cyclists Methods: Treatments: placebo (water); glucose (1.8 g/min); glucose + fructose (2:1 ratio; 1.8 g/min) Outcome variable: performance trial (~ 1 hr) after 120 min of cycling at 55% Wmax Results: Faster cycling time (8 %) for G/F vs G and 19% for G/F vs water Training the Gut to Absorb & Oxidize more! Cox et al., 2010; effect of carbohydrate intake during exercise training on carbohydrate oxidation highly trained athletes 1 group who consumed glucose during each of their workouts over a 4-week training block increased their ability to oxidize this carbohydrate, while muscle oxidation of carbohydrate consumed during exercise remained constant in a matched group Carbohydrate, water and electrolytes all work together to drive absorption! Carbohydrate Recommendations Duration <45 min min hrs hrs >2 hrs >3hrs Intensity any Med-high Med-high Med High Med-high Carbohydrate Amounts and Type None Mouth rinse; CHO type not important g/hr; CHO type not important 60 g/hr; CHO type not important Up to 90 g/hr; choose glucose + fructose at 2:1 ratio Jeukendrup, SCAN conference, San Diego, March, 2010; IOC Position Stand 2010 Pfeiffer et al also showed similar responses of CHO intake on oxidation rates in running; No difference btw solid vs liquid sources (Pfeiffer et al. 2011) 5

6 When to Add a Sport Drink, Gel or Bar Ø Depends on last meal and goal of training session Ø For prolonged and/or intense exercise > 2 hrs Ø In the heat, cold, at altitude Ø During acclimatization Ø Sodium is key! Ø When tired Ø To prevent muscle wasting Ø To support immune system Ø In competition Dehydration and Performance Weight loss from body water of as little as 2% of BW can lead to performance and impaired thermo-regulation Anderson Olympic Marathon Los Angeles, 1984 Exercise Capacity (%) A 2% BW loss in a 140 lbs person is 2.5 lbs Sweat rate is highly variable! Body Weight Loss (%) ~16 oz before Plenty of fluid before Hydration Strategies Replacement Guidelines: According to Sweat Rate Depending on environmental factors, ~ 6 oz ml every min 1. hour When thirsty 2. hour Sodium!! Plenty of fluid after; 1.5x of what you lost Maximal fluid consumption during exercise: ~32-35 oz per h more if you sweat a lot! Sweat Rate Assessment 1. Step: Record environmental condition 2. Step: Weight (before) - Weight (after) = loss 150 lbs 148 lbs = 2 lbs or 32 oz (1 lb = 16 oz; if you use kg use 1L for each kg lost) 3. Step: Add workout fluids consumed: 32 oz during 2 hrs cycling 32 oz + 32 oz = 64 oz or 2L 4. Step: divide by number of hours trained: 64 oz/2 hrs or 2L/2 Sweat Rate per hour= 32 oz/hr (or 1L/hr) 5. Step: record in log Avoid losing more than 2% of BW 33 Dehydration: Feedback Ø Daily Weight Fluctuations > 1% Ø Low urine volume in AM Ø Thirsty Ø Elevated AM heart rate Ø Moody & lethargic Ø Headaches Ø Urine Color Ø USG Ideal Hydration Dehydration Kidney Failure... To Optimize Performance. Sport drink, gels, blocs, bars, food 1. Sweat rate determines fluid and carbohydrate Ø g/hr of carb s from sport drink 2. Optimizing for intense training and racing Ø Adding gels, bars etc. to get g/hr carb s Ø Mixed carb s (glucose, fructose, sucrose) 3. Test your strategies in training! 4. GI issues 35 6

7 RECOVERY + SNACK CHO: 0.5 g/lb PRO: g Within 30 to 60 min next meal RECOVERY continues + SNACK min 60 min 60 min within min RECOVERY Carbs Protein Carbs Protein Fat RECOVERY Carbs Protein Fat Carbs Protein Fat Muscle glycogen 100% e Training Requires hrs to replete muscle glycogen stores h 0 Glycogen Resynthesis 85 % VO 2 max (hard) 65 % VO 2 max (moderate) The longer or harder your exercise the longer the time you need for recovery of glycogen stores Window of opportunity: Faster repletion within first few hrs of exercise h (adapted from: Mannhart, Colombani. Schweiz Z Sportmed Sporttraum 49: , 2001 ) 39 Relative Energy Deficiency in Sport (RED-S) The IOC Consensus Statement: Beyond the Female Athlete Triad Relative Energy Deficiency in Sport (RED-S) Mountjoy M, Sundgot-Borgen J, Burke L, et al. Br J Sports Med 2014;48: Energy Balance, Energy Availability Energy Deficiency ENERGY INTAKE 2500 kcal 1500 kcal = 1000 kcal EXERCISE ENERGY EXPENDITURE 2500 kcal 1500 kcal Enough to maintain basic physiologic function and health? < 30 kcal/kgffm? Energy Intake (kcal/kg/d) Exercise Energy Expenditure (kcal/ d) Energy Availability in Cyclists PS C OS Training Period 1423* 696 PS C OS Training Period male female male female Energy Availability (kcal/kg FFM/d) PS C OS Training Period male female Significant difference between male and female cyclists, p = Restrained eating (TFEQ) increased during offseason No differences in BMD across season 7

8 One Consequence of Energy Deficiency is Low Bone Mass Low BMD in endurance athletes (cyclists > runners; Rector et al., 2008) Loss of BMD throughout the season in cyclists (Barry and Kohrt, 2008) Reduced gonadal hormones in endurance runners (De Souza et al., 1994) Relative Energy Deficiency in Sport (RED-S) HEALTH Relative Energy Deficiency in Sport (RED-S) Assessing Risk of RED-S IOC Clinical Practice Models PERFORMANCE Color-coded risk stratification model for no-start criteria Success Stories from Norway Risk Assessment & No Start Criteria GREEN Risk Assessment & No Start Criteria YELLOW Full training and competition allowed with no stipulations Cleared to supervised training with a medical treatment plan May compete once cleared under supervision Re-evaluation at regular intervals (1-3 months) Regular reassessments for compliance and progress 8

9 Risk Assessment & No Start Criteria RED Clearance to participate in sport denied Athlete to receive treatment Use of a treatment contract advised Treatment of Energy Deficiency Treatment Team Ø Treatment team: MD, Psychologist, Sport Dietitian (CSSD), Physiologist, Physical Therapist, Coach Nutrition: Increase in energy availability (EA) ê RED-S Ø kcal/day (Dueck et al., 1996, Kopp-Woodroffe et al., 1999, Guebels et al., 2013) Ø Normalizing eating patterns and behaviors Ø Depending on the cause of LEA, psychological support Bone Building Nutrients Dietary Reference Intakes Bone Mass related to Calcium in Sweat in Cyclists Calcium (AI) Vitamin D (RDA) Newer recomm. Vitamin K (AI) y 1300 mg 200 IU b 1000 IU 75 1 μg/d = 40 IU a IOC Position Stand, 2014 b probably too low (Weaver, 2004) y 1000 mg 200 IU b 1000 IU 90 RED-S 1500 mg a IU Fish, milk IU c Supplements D Best Sources Dairy products Green leafy veggies c American Endocrine Society Measured sweat calcium loss at ~ 140 mg per 2 hour ride Barry and Kohrt, 2007 Supplementation w/ calcium can replace lost calcium, possibly improving BMD Barry and Kohrt, 2011 Ingest 1000 mg of Ca before long workouts Bone Loading to Prevent Osteoporosis Resistance Exercise Progression up to 8-10 reps x 2-3 Ø Free weights: squats, lunges Ø Leg press Ø Abductors, adductors, hip extension Ø Calf rises Ø Seated row Ø Lat pull down (posterior) Perform after endurance exercise not before Integrate recovery nutrition Jumping Insert multiple times per day Volume is not important (MES) Progression is necessary to prevent injury Ø Walking downstairs Ø Skipping Ø Box jumps up Ø Vertical counter-movement jumps Ø 1 legged alternates Ø Hurdles (low high) Ø Box jumps down (progression) Causes Blood loss Increased altitude, training load Poor Eating Habits Symptoms Fatigue (during training) Weakness Short of Breath Increased Heart Rate Iron Deficiency Diagnosed based on blood test (CBC, serum ferritin) Best treated with iron supplementation Martyn-St. James & Carroll, 2006; Menkes, 1993, Kato et al., 2005; Bassey et al., 1994 and

10 Supplement Concerns ü Regulatory Issues ü Contamination and Impurities ü Mislabeling ü Potential Side Effects ü Banned Substances ü Ineffectiveness Cohen American Roulette Contaminated Dietary Supplements, JEJM 361(16), pp Do Cyclists Need Supplements? Set the basic conditions for optimal training Adequate calories, CHO, PRO Removal of fad diets Optimal hydration Adequate bone nutrients Adequate iron intake Supplement to meet additional needs Calcium + vitamin D Iron? Multivitamin/minerals Caffeine, Nitrates, Beta Alanine Eat, Drink & Fuel Well!! Nanna Meyer, Sport Dietitian University of Colorado (UCCS) nmeyer2@uccs.edu 10