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nutrition by Jacqueline Berning, Ph D, RD, CSSD TEST 2: PAGE 90 Fueling Athletes for Training and Competition Nutrition recommendations for before, during and after workouts or com petitive events. Some of the questions most frequently asked of sports dietitians deal with food and flui d consumption befo re, during and after exercise. Indeed, athletes, are bom- barded with nutrition misinformati on, re- sulting i n confusion about what they should eat or drink during training or, more crucially, during competition. This article provides science-based guidelines on food and beverage choices that are ea sy to understand and adopt and that al- low athletes to maximize their po tential. Recently, th e American Dietetic Associati on, Dietitians of Canada and the American College o f Sports Medicine published a joint position statement re- garding nutrition and athletic perform- ance (Rodriguez et al. 2009). Among other topics, the position statement used evidence-based science to make recom- mendations for athletes on foo-d and fluid consumption before, during and afier ac- tivity. Using this document as a founda- tion, the guidelines described here have been developed to provide practical rec- ommendations that sports dietitians can use to help athletes make food and fluid choic es befor e, durin g and aft er workouts or competition. Preworkout Nutrition 1 . Athlete s should eat befor e physi cal ac- tivity as opposed to working out in a fasted state (Rodriguez et al. 2009). Consum ing foods high in carbohydrates (CHO) before exercise increases muscle glyc ogen stores and main tains blood glu- cose. Studies have s hown that consuming a pre-exercise meal low in fiber and fat , moderate in protein and high in CH O can extend the exercise time and provide added energy (lentjens et al. 2003; Moseley, Lancaster & Jeukendrup 2003). 2. At least 4 hours before activity, athletes should drink about 5-7 milliliters [ml| per kilogram of body weight (2-3 ml perpo undo f body weight) of water or sports drin k (Rodriguez et a L 2009). Consu ming flu ids at least 4 hours prior to a workout allows enough time to opti- mize hydration status and allow for ex- cretion of excess fluid (Rodriguez et al. 2009). Fluid consumption will vary depending o n environmental factors, exerci se intensity, bod y size, training sta- tus and gender. A sports drink consumed before exercise should contain 6%-8% CHO (60-80 grams CHO per liter) and 110-165 milligrams o f sodium per 8 - January 2011 IDEA Fitness Journal ounce (oz) serving (Chryssanthopoulos & Williams 1997; Chryssanthopoulos et al. 2002). 3. The volume of the preworkout meal or snack, the timing of ingestion an d the start of the workout are all interre- lated (Rodriguez et al. 2009). Athletes should consume smaller meals closer to the start of a competition, whil e larger meals should be consumed further out fr om the workout. Studies on CHO in which athletes consume 200-300 g of CHO 3-4 hours before competition have shown that this helps performance (Rodriguez et al. 2009; Bloch & Wheeler 1999). Athletes may benefit from con- suming liquid CHO, such as pre-exercise beverages or gels (25 g CHO/4 oz) or sports drink (containing 6%-8% CHO solution) an hour or less before the start of activity (Anantaraman e t al. 1995). Consuming a concentrated source o f CHO around 15 minutes before a work- out works well when athletes do this in conjunction with CHO intake during that workout. 4. Athletes' individual needs and prefer- ences should be identified and met (Rodriguez et al. 2009). » 7 1
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7/28/2019 Fueling Athletes

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n u t r i t i o n b y J a c q u e l i n e B e r n i n g , Ph D, RD, C S S D

TEST 2:

PAGE 90

Fueling Athletes forTraining and CompetitionNu trition recom mendations for before, during and after workouts or com petitive events.

Some of the questions most frequentlyasked of sports dietitians deal with food

and fluid consumption before, during and

after exercise. Indeed , athletes, are bom -

barded with nutrition misinformation, re-

sulting in confusion about what they

should eat or drink during training or,

more crucially, during competition. Th is

article provides science-based guidelines

on food and beverage choices that are

easy to understand and adopt and that al-

low athletes to m aximize their po tential.

Recently, the American DieteticAssociation, Dietitians of Canada and the

American College of Sports Medicine

published a joint position statement re-

garding nutrition and athletic perform-

ance (Rodriguez et al. 2009). Among

other topics, the position statement used

evidence-based science to make recom-

mendations for athletes on foo-d and fluid

consumption before, during and afier ac-

tivity. Using this docu men t as a founda-

tion, the guidelines described here have

been developed to provide practical rec-omm endations that sports dietitians can

use to help athletes make food and fluid

choices before, during and after workouts

or competition.

Preworkout Nutrition1. Athletes should eat before physical ac-

tivity as opposed to working out in a

fasted state (Rodriguez et al. 2009).

Consum ing foods high in carbohydrates

(CHO) before exercise increases muscle

glycogen stores and main tains blood glu-

cose. Studies have shown that consum ing

a pre-exercise meal low in fiber and fat,

moderate in protein and high inCHO

can extend the exercise time and provide

added energy (lentjens et al. 2003;

Moseley, Lancaster & Jeukendrup 2003).2. At least 4 hours before activity, athletes

should drink about 5-7 milliliters [ml|

per kilogram of body weight (2-3 ml

perpo undo f body weight) of water or

sports drink (Rodriguez et aL 2009).

Consuming fluids at least 4 hours prior to

a workout allows enough time to opti-

mize hydration status and allow for ex-

cretion of excess fluid (Rodriguez et al.

2009). Fluid consumption will vary

depending on environmental factors,

exercise intensity, bod y size, training sta-

tus and gender.A sports drink consumed

before exercise should contain 6%-8%

CHO (60 -80 grams CHO per liter) and

110-165 milligrams of sodium per 8-

January 2011 IDEA Fitness Journal

ounce (oz) serving (Chryssanthopoulos& W illiams 1997; Chryssanthopoulos et

al. 2002).

3. The volume of the preworkout meal or

snack, the timing of ingestion and the

start of the workout are all interre-

lated (Rodriguez et al. 2009).

Athletes should consume smaller meals

closer to the start of a competition, while

larger meals should be consumed further

out from the workout. Studies on CHO in

which athletes consume 200-300 gof

CHO 3 -4 ho urs before competition haveshown that this helps performance

(Rodriguez et al. 2009; Bloch & Wheeler

1999). Athletes may benefit from con-

suming liquid CHO, such as pre-exercise

beverages or gels (25 g CHO/4 oz) or

sports drink (containing 6%-8% CH O

solution) an h our o r less before the start

of activity (Anantaraman et al. 1995).

Consuming a concentrated source of

CHO a round 15 minutes before a work-

out works well when athletes do this in

conjunction with CHO intake during thatworkout.

4. Athletes' individual needs and prefer-

ences should be identified and met

(Rodriguez et al. 2009). »

7 1

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Athletes should always experiment with

the type, amount and t iming of a pre-

work out m eal before a t rain ing sess ion;

they should not start a new strategy at the

time of a compe tition. T his will allow ath -

letes to find meals that work for their

events and not interfere with pe rformance .

Nu tr i t ion Dur ing a Workout1. Research supports the benefit that

CHO consumption in amounts typi-

cally provided in sports drinks

(6%-8% CHO) has on endurance per-

formance in events lasting 1 hour or

less (Rodriguez et al. 2009; Sugiura &

Kobayashi 1998; Jeukendrup et al.

1997; Nicholas et al. 1995).

2.For

longer events, consuming 30-60 gCHO/bour has been shown to extend

endurance performance (Rodriguez et

aL2009).

This is especially impo rtant for athletes who

have not consume d a preworkout meal or

have restricted calories or CH O du ring ex-

ercise, for mainten ance of blood glucose.

3. Consumption of6 -12 oz of sports drink

with 6%-8%CHO every 15-30 minutes

during a workout can extend the work-

out capacity of athletes w ho p articipate

in interm ittent activity (Jeukendrup etal. 1997; Anantaraman et al. 1995;

Below et aL 1995; Carter et aL 2003; el -

Sayed, Balmer & Rattu 1997).

Nutrit ion forPostworkout and Recovery1. It is imp ortan t to replace fiuids and

electrolytes that are lost during activ-

ity. Consum ing rehydradon beverages

and salty foods during m eals/snacks

will help replace fluids and electrolyte

losses (R odriguez et al. 2009).

Athletes should drink 16-24 oz of fluid

for every pou nd of body weight lost (and

not replaced) during activity (Rodriguez

et al. 2009). It should be recognized that

complete rehydration requires sufficient

sodium and potass ium replacement and

extra fluid intake exceeding that which is

lost in sweat and urine during activity.

2. Timing and composit ion of the

postexercise m eal depends on the in-

tensity and duration of the exercise

session and wben the next workout

will occur (Rodriguez et al. 2009).

Not all athletes need to practice recovery

nutri t ion . For example, a cross-country

runne r w ho trains in easy runs before a ta-

It is importantto replacefluids and

electrolytestha t are lostduring activity.

pering week does not empty glycogen

stores and has enough time for complete

recovery before co mpetition. For those d o-

ing intense training m ultiple times a day,

an appropriate diet strategy between work-

outs will be very relevant and imp ortan t.

3. Timing of postworkout CHO intake

affects glycogen synth esis.

Consumption of 1.0-1.5 g of CH O/kg with-

in 30 min utes after exercise and at 2-hour

intervals (up to 6 hours) results in higher

glycogen levels than when ingestion is

delayed for 2 hours (Rodriguez et al. 2009).

Wh en the recovery period is limited to

only a few hour s , rehydrat ion a nd refu-

el ing can be achieved by ingest ing a

CHO -electro lyte solut ion in volumes of

at least 150% of the workout-induced loss

in body weight and by consuming C HO -

rich foods (M oore et al. 2009).

4. Protein plays a role in recovery nutri-

t ion.

The jo in t posi t ion s tatem ent ad dressed

the fact that add ing protein to a recovery

regimen does not increase muscle glyco-

gen to a greater extent than CHO alone

when CH O i s consum ed in recom-

mend ed am ounts (R odriguez et al. 2009).

However, adding protein to the recovery

snack v«ll provide am ino acids for build-

ing, maintenance and repair of muscle.

Wh ile CH O is the prima ry source of

energy for muscles , consuming a small

am oun t o f p ro te in sho r t ly af t e r ac t iv -

ity assists in the repair and synthesis of

musc le p ro te in in the body . Ath le tes

should meet their protein requirements

b y c o n s u m i n g p ro t e in t h ro u g h o u t t h e

day rather than ingest ing i t a l l in one

meal or snack. Research by Howarth et

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a l. (2009) suggests that aboat 20 g of

protein is the maximum amount

needed to stimulate synthesis and repair

of muscle.

In addition, research shows that in-

gestion of 7-10 g of protein a long with

CHO within 30 minutes of physical a c-

tivity is enough to start muscle protein

synthesis. Repeated feedings up to 6

hours postworkout may help provide a

pulsing effect for muscle rebuilding over

time (Moore et al . 2009).

Opt imal Nut r i t ion TowardOptimal PerformanceAdopting nutrition strategies presented

within the joint position statement can

improve physical a ctivity tolera nce an dhelp athletes recover rapidly from train-

ing and competition. An important

premise of these general recommenda-

tions is that the optimal mixture of nu-

trients to speed recovery from hard

training and competition can be ob-

tained by eating wholesome foods and

beverages, provided correct choices are

made regarding food type, am ount a nd

timing. •

Jacqueline Beming, PhD, RD, CSSD is a

professor at the University of Colorado at

Colorado Springs, and sports dietitian for

Major League Baseball's Colorado Rockies

and Cleveland Indians. She also is a nutri-

tion consultant to The Gatorade Sports

Science Institute.

ReferencesAna ntara ma n, R. , et al . 1995. Effects of carbohydra lc

supplementation on performance during 1 hour of

high intensity exercise, lnternalional journal ofSporls

Medicine, /6 (7), 461-65.

Below, R, et al. 1995. Fluid and carixihydra te ingestion

independently improve performance during 1 h of in-

tense exercise. Medicine & Science in Sports and

Exercise, 27(2), 200-210.

Bloch, T.D., & Wheeler, K.B. 1999. Dietary exa mples: A

practical apprt>ach to feeding a thletes. Clinics in Sports

Medicine, ; 8 ( 3 ) , 703-711.

Carter, J., et al . 2003. Carbohydra te .supplementation im-proves moderate and high-intensity exercise in the

heat. Pßügers Archiv, 446 (2), 211-19.

Chryssanthopoulos, C, & Willia ms, C. 1997. Pre-exer-

cise carimhydrate meal a nd endurance running capac-

ity when carbohydrates are ingested during exercise.

International¡oumd ofSports Medicine, 18 (7), 543^)8.

Chryssa nthopoul os, C , et al. 2002. The effect of a high

carbohydra te mea l on endura nce running capa ci ty .

International Journal of Sport Nutrition and Exercise

Metabolism, ¡2(2), 157-71.

el Sayed, M.S. , Balmer, ( . , & Rattu, A.) .M. 1997.

Carbohydrate ingestion improves endurance per-

formance dur ing a 1 h simulated cycling time trial .

loumal of Sports Sciences, (5(2), 223-30.

How arth, K.R., et al. 2009. Coingestion of protein with

carbohydrate during recovery frt)m endurance exercise

stimulates .skeletal muscle protein synthesis in humans.

loumal ofApplied Physiology, /06 (4), 1394-1402.

Jentjens, R.I. ., et al . 2003. Effects of pre-exercise inges-

tion of differing am ounts of carbohydrate on subse-

quent metabolism and cycling performance. European

journal of Applied Physiology, 8 8 (4-5), 444-52.

leukendrup, A.E. , et al . 1997 C arbohydrate-electrolyte

feedings improve I h time-trial cycling performance.

International journalof SporU Medicine, I8{2), 125-29.

M(K)re, D.R., et al. 2009. Ingested protein dose response

of muscle and albumin protein synthesis after resist-

ance exercise in young men. American journal of

Clinical Nutrition, 89(1), 161-68.

Moseley, L, I.ancaster, G.I., & leukendrup, A.R 200.3. Effects

of timing of pre-exercise ingestion of carbohydra te on

subsequent metabolism and cycling performance.

European journal of AppliedPhysiology, 88 (4-5), 453-58.

Nichola s, C.W., et al . 1995. influence of ingesting a ca r-

bohydrate-electrolyte solution on endurance capacity

during interm ittent, high intensity shuttle running.

journal of Sports Sciences, 13 (4), 83-90.Rodriguez, N.R., et al. 2009. Position of the American

Dietetic A.s .sociation, Dietitians of Cana da , an d the

American Q>llege of Sports Medicine: Nutrition and

athletic performance, journal of the American Dietetic

Association, 109(3), 509-527.

Sbirreffs, S.M., et al. 1996. Postexercise rehydration in

ma n: Effects of volume consumed and sodium content

of ingested fluids. Medicine & Science in Sports &

Exercise, 28 (10), 1260-71.

Sugiura, K., & Kobayashi, K. 1998. Efiect of carbohydrate

ingestion on sprint performance following continuous

and intermittent exercise. Medicine & Science in Sports

& Exercise, 30 ( 11 ), 1624-30.

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