November 2013 Issue

Postexercise Recovery — Proper Nutrition Is Key to Refuel, Rehydrate, and Rebuild After Strenuous Workouts
By Marie Spano, MS, RD, CSCS, CSSD
Today’s Dietitian
Vol. 15 No. 11 P. 18

A slight breeze goes unnoticed as Andre slowly makes his way off the football field. Physically and mentally drained from a grueling three-hour practice in full gear, he pulls off his helmet as the sting of salty sweat trickles into his eyes. Andre wipes his forehead and brushes the back of his hand against the side of his face, where sandy grit from the white sodium crystals are glued to his cheeks. In slow motion, he walks toward the locker room where he needs to muster the energy to go through his postworkout recovery routine.

After intense workouts, athletes are physically depleted, dehydrated, and mentally exhausted. Therefore, recovery nutrition must have three primary goals: refuel, rehydrate, and repair and build. Replenishing vital nutrients, rehydrating and restoring electrolyte balance, repairing damaged muscle tissue, and attenuating excessive inflammation accomplish these goals.1,2 Adequate recovery is critical to enable athletes to better respond to increases in training volume and intensity and perform at their best.3

Refueling
Following vigorous exercise, athletes must consider when, what, and how much to eat and drink—important components of a recovery nutrition plan.1 The what and how much to eat and drink depend on the sport, the training program, environmental factors, the athlete’s health history, body composition and size, performance goals, and physical conditioning. All three components are referred to as “nutrient timing,” or the timing of nutrient delivery to the body.

Because exercise sensitizes muscle tissue to certain hormones and nutrients, muscle is most responsive to nutrient intake during the first 30 minutes postexercise. And although this metabolic window of opportunity diminishes as time passes, certain types of exercise, such as resistance training to the point of muscular fatigue, keep the window open for up to 48 hours. Therefore, athletes must be cognizant of what they consume each day and when. Physical training takes place in succinct bouts, but the nutrition segment of a training program extends to all waking hours and must include the replenishment of several nutrients to promote postexercise recovery.

Glycogen Replenishment
Glycogen, which is stored in the muscles, is the fuel source athletes must restore following strenuous training. Muscle glycogen is the predominant fuel source used during long bouts of aerobic exercise. In fact, aerobic performance is directly related to initial glycogen stores. Once glycogen is depleted, the athlete will feel fatigued and performance will suffer.4 High-glycemic carbohydrate foods, such as white bread, candy made from dextrose, or maltodextrin supplements, will replenish glycogen stores when consumed immediately following workouts since muscle tissue is spongelike and therefore will rapidly soak up glucose from the high-glycemic carbohydrates.

Anaerobic exercise also is fueled almost entirely by carbohydrates, according to Sally Hara, MS, RD, CSSD, CDE, of ProActive Nutrition in Kirkland, Washington. “There isn’t enough oxygen available during anaerobic exercise to use the oxidative pathway necessary to use fat as a fuel,” she says. “So if there’s insufficient carbohydrate available, the body will turn to protein for fuel.”

Without enough carbohydrate, glycogen stores drop significantly after both aerobic and anaerobic exercise, which could affect subsequent performance if it isn’t replaced. And while some athletes may argue that they can “function with lower carbohydrate levels than what’s generally recommended for them, there’s a difference between functioning and performing optimally,” Hara says. “Coaches often report that athletes who follow low-carbohydrate diets fatigue early and make more cognitive mistakes.”

The best way athletes can quickly replenish muscle glycogen is to consume 1.5 g of high-glycemic carbohydrates per 1 kg of body weight immediately after exercise. If the athlete delays carbohydrate consumption by two hours or more, glycogen synthesis will be reduced by 50%.5 Another way to restore glycogen is to consume 0.6 to 1 g of high-glycemic carbohydrate per 1 kg of body weight right after exercise and again every two hours for four to six hours.6,7 In addition, ingesting protein along with carbohydrate can increase muscle glycogen stores when insufficient total carbohydrate is consumed or when carbohydrate intake is consumed in intervals spread out by more than one hour.1

Rehydration and Electrolyte Balance
Fluid and electrolyte losses after vigorous workouts vary among athletes, so it’s important for them to monitor the quantity and color of their urine to assess hydration status. Urine color should be clear, and there should be a plentiful amount. Coaches can keep track of fluid losses by weighing athletes before and after training. Fluid losses shouldn’t exceed 2% of body weight. If they do, this means the athlete isn’t maintaining a safe hydration level. For every pound of fluid lost, athletes should consume 20 to 24 oz of fluid.8

Moreover, postworkout fluids or meals should contain sodium, particularly for athletes who lose large amounts of sodium through sweat. Research studies have found sodium losses in sweat range from 172 to 1,139 mg/1 lb of sweat in football and soccer players.9-12 Athletes can choose sports drinks that contain sodium or water along with a meal that contains sodium.

Repair and Build
In addition to fluid and electrolyte losses, training increases circulating catabolic hormones to facilitate the breakdown of glycogen and fat for fuel. These hormone levels remain high after exercise and continue to break down muscle tissue. Without nutrient intake, this catabolic cascade continues for hours postexercise, contributing to muscle soreness and possibly compromising training adaptations and subsequent performance.

To repair and build muscle, athletes must refuel with high-protein foods immediately following exercise, especially after resistance training. They should consume 20 to 40 g of protein that includes 3 to 4 g of leucine per serving to increase muscle protein synthesis.13 While research has shown 20 g of whole egg protein can stimulate muscle protein synthesis in young, healthy men, the literature suggests that higher amounts are necessary in athletes over the age of 71 and possibly at younger ages, although this hasn’t been fully determined.14

In addition, whey is an optimal postworkout protein because of its amino acid composition and the speed of amino acid release into the bloodstream. And while it’s crucial to replenish the body with protein and amino acids immediately after exercise, athletes need to eat protein regularly throughout each day to stimulate whole-body protein synthesis until muscle failure sensitizes muscle tissue to protein for up to 48 hours after exercise.15

What many athletes often overlook is the importance of carbohydrate intake for building and repairing muscle. Carbohydrate can decrease muscle protein breakdown by stimulating insulin release. Resistance training athletes benefit from consuming carbohydrates and protein after strenuous workouts.16 Complete nutrition shakes help rehydrate athletes while providing both carbohydrate and protein postworkout.

Attenuating Excess Inflammation
Athletes who get the required amounts of leucine-rich protein and carbohydrate immediately after exercise turn that crucial time period from a catabolic state to an anabolic state.1 Muscle tissue breakdown ceases as proper nutrient intake upregulates processes underlying muscle growth and repair while replenishing muscle glycogen.

To help curb excessive inflammation and muscle soreness, researchers have examined various products and ingredients. In particular, tart cherry juice and ginger (fresh or heat treated) have been found to decrease eccentric-exercise–induced inflammation and delayed onset muscle soreness.17,18 Studies indicate the flavonoids and anthocyanins in tart cherries are responsible for suppressing inflammation.17 In vitro studies have found several chemical constituents in ginger, such as gingerols, shogaols, paradols, and zingerone, that block the production of inflammatory compounds and inhibit enzymes that increase pain and inflammation in the body.18

Specific Considerations
While recovery nutrition has three primary goals, the manner in which these goals are achieved depends on the type of sport an athlete plays. Based on sports science research, nutrition recommendations for athletes are divided into two categories: endurance sports and resistance training. However, these categories don’t address the gray areas of nutrition requirements for athletes who participate in team sports where training intensity and the effects of training may significantly vary and differ among athletes on the same team. A sports dietitian can develop individualized plans for each athlete, keeping in mind that plans may change based on training adaptations, changes in growth and body composition, injuries, illness, and training phase.

“Proper recovery is essential for an athlete to build on any gains from a workout, practice, or game,” says Sarah Snyder, MS, RD, CSSD, USAW, director of sports nutrition at the University of Florida in Gainesville. “It allows them to bounce back and to be fresh for subsequent practices, workouts, or games.”

Snyder advises sports dietitians to help athletes choose postworkout foods they like and that are portable so they’re more inclined to meet their requirements. “Recovery can be as simple as a grab-and-go meal or shake,” she says. “In the college setting, we make this available and have a system in place for all athletes to grab something in the weight room on their way out. We educate them on their postlift needs during their individual nutrition consults. Many eat dinner postpractice at our training table or at the dining hall where a dietitian is available for live plate coaching as well.”

Importance of Sports Dietitians
Sports dietitians play an essential role in helping athletes recover from training. They work with a development staff to better tailor each individual athlete’s postworkout nutrition program and continually reassess and revise each plan based on training gains, changes in training, growth and development, and other factors to ensure each athlete progresses physically and mentally and performs at his or her best.

— Marie Spano, MS, RD, CSCS, CSSD, is a sports nutrition expert, spokesperson, and nutrition communications consultant.

 

References
1. Ivy JL. Regulation of muscle glycogen repletion, muscle protein synthesis and repair following exercise. J Sports Sci Med. 2004;3:131-138.

2. Casa DJ, Armstrong LE, Hillman SK, et al. National Athletic Trainers’ Association position statement: fluid replacement for athletes. J Athl Train. 2000;35(2): 212-224.

3. Bishop PA, Jones E, Woods AK. Recovery from training: a brief review. J Strength Cond Res. 2008;22(3):1015-1024.

4. Coyle EF, Coggan AR, Hemmert MK, Ivy JL. Muscle glycogen utilization during prolonged strenuous exercise when fed carbohydrate. J Appl Physiol. 1986;61(1): 165-172.

5. Ivy JL. Glycogen resynthesis after exercise: effect of carbohydrate intake. Int J Sports Med. 1998;19 Suppl 2: S142-145.

6. Jentjens RL, van Loon LJ, Mann CH, Wagenmakers AJ, Jeukendrup AE. Addition of protein and amino acids to carbohydrates does not enhance postexercise muscle glycogen synthesis. J Appl Physiol. 2001;91(2):839-846.

7. Jentjens RL, Jeukendrup AE. Determinants of post-exercise glycogen synthesis during short-term recovery. Sports Med. 2003;33(2):117-144.

8. Dunford M, Doyle JA. Nutrition for Sport and Exercise. 1st ed. Belmont, CA: Thompson Higher Education; 2007.

9. Shirreffs SM, Maughan RJ. Whole body sweat collection in humans: an improved method with preliminary data on electrolyte content. J Appl Physiol. 1997;82(1):336-341.

10. Maughan RJ, Merson SJ, Broad NP, Shirreffs SM. Fluid and electrolyte intake and loss in elite soccer players during training. Int J Sport Nutr Exerc Metab. 2004;14(3):333-346.

11. Maughan RJ, Watson P, Evans GH, Broad N, Shirreffs SM. Water balance and salt losses in competitive football. Int J Sport Nutr Exerc Metab. 2007;17(6):583–594.

12. Godek S, Peduzzi C, Burkholder R, Condon S, Dorshimer G, Bartolozzi AR. Sweat rates, sweat sodium concentrations, and sodium losses in 3 groups of professional football players. J Athl Train. 2010,45(4):364-371.

13. Yang Y, Breen L, Burd NA, et al. Resistance exercise enhances myofibrillar protein synthesis with graded intakes of whey protein in older men. Br J Nutr. 2012;108(10):1780-1788.

14. Moore DR, Robinson MJ, Fry JL, et al. Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. Am J Clin Nutr. 2009;89(1):161-168.

15. Wolfe RR. Skeletal muscle protein metabolism and resistance exercise. J Nutr. 2006;136(2):525S-528S.

16. Glynn EL, Fry CS, Drummond MJ, et al. Muscle protein breakdown has a minor role in the protein anabolic response to essential amino acid and carbohydrate intake following resistance exercise. Am J Physiol Regul Integr Comp Physiol. 2010;299(2):R533-R540.

17. Connolly DA, McHugh MP, Padilla-Zakour OI, Carlson L, Sayers SP. Efficacy of a tart cherry juice blend in preventing the symptoms of muscle damage. Br J Sports Med. 2006;40(8):679-83.

18. Black CD, Herring MP, Hurley DJ, O’Connor PJ. Ginger (Zingiber officinale) reduces muscle pain caused by eccentric exercise. J Pain. 2010;11(9):894-903.