Posted: February 5, 2006

Nutrition: Staving Off Muscle Soreness--Nutritional Strategies that Work

By: Kim Mueller, MS, RD, SDTC Sports Nutritionist

As you fight for survival on your last interval or final mile of long marathon training run, you may wonder if your body will ever fully recover from the beating of the workout. While muscular fatigue and soreness are inevitable after intense workouts and thus the emphasized importance of recovery days by coaches, cutting edge scientific research has shown that use of certain nutritional strategies prior to, during, and after training can minimize muscle damage and aid quick muscle recovery, ultimately helping to rejuvenate your muscles for peak performance at your next workout. Here’s the latest scoop….

Priming your Muscles for Peak Performance

Priming your muscles for peak performance entails that a carbohydrate-oriented meal be consumed prior to higher intensity training (e.g., intervals, tempo runs, racing) lasting greater than one hour or aerobic-based training (e.g., long runs) lasting greater than 90 minutes. This is especially important when workouts are planned after an overnight fasting state, which is shown to reduce liver glycogen (carbohydrate) stores and corresponding blood sugars, thereby contributing to a mental “bonking” state within the athlete.1 Carbohydrates consumed prior to longer training days helps to restocks our liver with glycogen, helping to stabilize energy levels during the initial stages of activity. In endurance training, this pre-workout meal also helps spare the limited supply of glycogen stored in our muscles, thereby preventing premature muscle fatigue and cramping (aka “the wall”) often experienced around mile 18-20 of the marathon.2 This is extremely beneficial when looking at post-workout muscle recovery since premature depletion of muscle glycogen elevates breakdown of muscle protein and consequent muscle soreness.

Because low-to-moderate glycemic carbohydrates (e.g., most fruits, whole grains, dairy) promote more stable energy levels during prolonged exercise and have been shown in research to provide significant performance and metabolic advantages as compared to high glycemic carbohydrates (e.g., refined white flour, baked goods), these carbohydrates should be emphasized pre-exercise.3 High glycemic carbohydrates, which include most sport drinks and gels, are appropriate for consumption within an hour prior to starting, but should not make up the majority of a meal eaten more than 1 hour prior to starting a workout. The glycemic value of various carbohydrate-rich foods can be found at www.glycemicindex.com.

Ingestion of protein with carbohydrate in approximately a 1-4:7 ratio pre-workout may provide additional benefit to the endurance athlete since protein has been reported to increase insulin and/or growth hormone levels to a greater degree than ingestion of carbohydrate alone.4,5 Consequently, ingesting protein and carbohydrate prior to exercise may help decrease the body’s reliance on muscle proteins for energy during the later stages of a workouts, thereby serving as an anti-catabolic nutritional strategy.6 Sample sources of protein that seem to be well- tolerated by athletes include low-fat or non-fat dairy products like yogurt and milk, nut butter, eggs, and protein powder.

As a general rule, for every hour prior to starting your workout, endurance athletes should aim at consuming approximately 2 calories per pound of lean body weight. For most female athletes, this equates out to approximately 40-60 grams of carbohydrate and 5-15 grams of protein (~200 calories) for every hour prior to starting. For most male athletes, this equates out to be approximately 60-75 grams of carbohydrate and 7-18 grams of protein (~250-300 calories) for every hour prior to starting. Refer to table 1 for some sample pre-workout meals that have put to use by many endurance athletes, including myself. However, since everyone is unique in what foods they can tolerate pre-workout, be sure to experiment with these foods during training rather than having a field experiment gone badly on race day.

Table 1 Sample Pre-Workout Meals

Sample Pre-Workout Meals	Calories	Carbohydrate (grams)	Protein (grams)
1 cup nonfat vanilla yogurt blended with 1 cup strawberries	200	40	10
2 Eggo low-fat Nutri-Grain waffle spread with 1 Tbsp natural peanut butter and 1 Tbsp dark honey.	300	50	9
1 energy bar (Clif®, Powerbar®, Boulder® bar) plus 1 banana	345	65	13
2 cups Special K® cereal topped with ¾ cup blueberries and 1 cup nonfat milk. Serve with 1 cup 100% fruit juice.	475	100	25
Island Smoothie: Blend 1 cup 100% pineapple juice, 1 cup nonfat key lime yogurt, 1/2 cup frozen sliced mango, 1 sliced frozen banana, and 1 Tbsp vanilla whey/soy/egg protein powder.	570	120	20

Minimizing Muscle Damage during Training

While it would be nice if we all had an unlimited supply of glycogen to rely on during prolonged training bouts, the truth is that well-nourished athletes only have the capacity to store 1,500-2,000 calories of glycogen, which is enough to support approximately 18-20 miles of running. Therefore the goal is to spare muscle glycogen and protein while soaking up the ever-so-abundant supply of energy available from fat (~100,000 calories). Training does enhance our body’s ability to utilize fat as a fuel, yet nutrition becomes of paramount performance during runs extending beyond 25 kilometers. Unfortunately, because the maximum rate of absorption of carbohydrate during prolonged training falls about 50% short of the actual depletion rate from our muscles and liver, amino acids, which are supplied via breakdown of muscle protein, inevitably start to supply an increasing amount of energy towards the later stages of a workout. In fact, during extended exercise, up to 15% of the working muscles' total energy needs may come from protein. This can lead to significant net muscle protein loss during workouts, increasing the athlete’s susceptibility to muscle damage, potential injury, and slowed recovery.

In order to prevent muscle protein breakdown, it is essential to start refueling your engine beyond 60-90 minutes of high intensity training and 90-120 minutes of aerobic-based training. A carbohydrate solution is appropriate for runs lasting up to 120 minutes but there is an increasing evidence showing for the benefits of protein use during endurance training. The most dramatic proof of protein's benefits in a sports drink was shown in a study conducted at the University of Texas. Researchers compared the effects of a conventional 7.75% carbohydrate sports drink to a carbohydrate-protein sports drink containing the same amount of calories in cyclists during a high-intensity cycling bout to exhaustion. The carbohydrate-protein solution slowed the rate of glycogen depletion, thereby enhancing endurance performance, by 24 percent as compared to the carbohydrate solution.7 Exercise physiologists at Springfield College in Massachusetts reported similar results with a protein-containing sports drink. They compared the effect of a carbohydrate solution to a carbohydrate-protein solution with respect to their ability to help athletes meet the demands of two-a-day workouts. Following a treadmill run of moderate to high intensity, the subjects consumed either a carbohydrate drink or a carbohydrate-protein drink during a 60-minute recovery period. This was followed by a high-intensity treadmill run to exhaustion. The subjects in the carbohydrate-protein group were able to run 20% longer than the subjects receiving the carbohydrate drink.8

The key factor associated with glycogen-sparing effect appears to be insulin. Insulin levels, measured by the Springfield College researchers, were twice as high in the carbohydrate-protein group as in the carbohydrate group. The authors concluded that the carbohydrate/protein drink induced a greater rate of muscle glycogen replenishment than a carbohydrate-only drink, which translated into improved exercise endurance during a second bout of exercise performed on the same day. Researchers at University of Texas Health Science Center have also found that insulin increases the rate of transport of key amino acids into the muscle from 20% to 50%, thereby promoting protein synthesis rather than degradation.9 In fact, according to researchers at James Madison University, there is a corresponding 83% reduction in creatine phosphokinase (CPK), a biomarker of muscle damage, when endurance athletes use a carbohydrate-protein solution during prolonged or high intensity training. Therefore, it is feasible to conclude that a carbohydrate-protein solution consumed during training will be extremely beneficial to runners engaged in two-a-day workouts, high intensity training, or high-mileage training regimens

The following equations can be used to determine hourly carbohydrate and protein needs during high intensity training lasting at least 60 minutes or aerobic-based training lasting at least 90 minutes:

0.5 grams of carbohydrate x lean body weight in pounds

Up to 0.125 grams of protein x lean body weight in pounds

Remember to experiment with protein during training rather than implementing for the first time on race day. As a general rule, for every 20 grams of carbohydrate, 3-4 grams of protein (~1-2 tsp protein powder) should be added.

A Sampling of Sports Foods Containing Both Carbohydrate & Protein (or Amino Acid)

Accelerade, www.accelerade.com
Accel Gel, www.accelerade.com
Clif Bar, www.clifbar.com
Cytomax, www.cytomax.com
Infinit Customized Sports Drinks, www.infinitnutrition.com
Perpetuem Sports Drink, www.e-caps.com
Powerbar Energy Bar, www.powerbar.com
Powerbar Performance Recovery Drink, www.powerbar.com
Spiz, www.spiz.net
Sustained Energy, www.e-caps.com

Muscle Recovery

According to the late Edmund Burke, PhD, a renowned exercise physiologist and fellow endurance athlete, recovery from extended training can be broken down into three parts--The Rapid Phase, The Intermediate Phase, and The Longer Phase. Each part focuses on specific nutritional aspects of recovery, which I explain in the forthcoming paragraphs.

The Rapid Phase

The rapid phase encompasses a 30-minute window immediately post-workout and is designed to help replenish depleted muscle glycogen stores and account for any damaged or lost muscle protein. Many studies have proven the existence of a muscle recovery window for protein and glycogen synthesis. In one such study, performed at Vanderbilt University, glycogen replenishment occurred 3.5 times faster when subjects were fed a carbohydrate-protein solution within 30 minutes versus 3 hours after a 60 minute moderate-intensity effort. Muscle protein synthesis also proceeded more than 3 times faster when replenishing within the 30-minute window.10 Similar results, which yielded a 38% greater rate of glycogen replenishment rate with use of a carbohydrate-protein solution rather than a carbohydrate-only solution within 30 minutes after a 2 hour cycling bout, were published by researchers at the University of Texas. These researchers also discovered that this carbohydrate-protein solution enhanced the rate of glycogen storage by 5 times as compared to a protein-only supplement. 5

Dr. John Ivy of the University of Texas at Austin attributes this desirable physiological response to our heightened sensitivity to insulin post-workout. Insulin, a hormone produced by the pancreas, helps deliver amino acids, proteins, and carbohydrate to our depleted muscle cells. When carbohydrate and protein are consumed together, there is a greater insulin response than when either nutrient is taken alone, ultimately aiding muscle glycogen replenishment and muscle protein synthesis. In fact, a well-known Dutch study demonstrated a 100% greater blood insulin response when carbohydrates were combined with protein and amino acids rather than consumed alone.11

While there seems to be a heightened phobia with high glycemic carbohydrates, these types of carbohydrates (e.g., glucose; go to www.glycemicindex.com for more examples) are preferable for consumption post workout due to their ability to solicit a quicker insulin response. To obtain the optimal nutritional formula for enhanced muscle recovery, high glycemic carbohydrates should be balanced with protein in a 4:1 ratio. Athletes stuck on the mentality that protein should be favored post workout should be aware that a recovery ratio favoring protein will actually reduce the rate of gastric emptying, slowing the transfer of nutrients to the muscles, ultimately sabotaging the muscle recovery window. To obtain the proper caloric volume for optimal muscle recovery, runners should aim at consuming ½ gram of high glycemic carbohydrate and 1/8 gram of protein per pound of lean body weight within 30 minutes of high intensity or prolonged training bouts. For most athletes, this equates out to be 40-80 grams of carbohydrate and 10-20 grams of protein or approximately 200-400 calories. Samples of post-workout recovery foods include low-fat chocolate milk, meal replacement shakes like Boost® or Ensure®, recovery-based sports drink like Endurox®, peanut butter and banana sandwiches, mashed potatoes prepared with low-fat milk, and energy bars.

Intermediate Phase

The intermediate phase extends 2 hours beyond completion of training and is focused on continued replenishment of glycogen and protein as well rehydration. Many athletes complete a workout in a 1-2% dehydrated state, which is an involuntary response secondary to the fact that when training in extreme conditions (e.g., heat, altitude), we cannot always physiologically absorb the amount of fluid we lose. Unfortunately, this leads to a “dry” state within our muscles contributing to muscle cramping, muscle aches, and an overall sense of fatigue. Furthermore, in order to maximize our metabolic processes post-workout, which includes breakdown and transport of carbohydrate and protein to the muscles, a state of euhydration is critical. Therefore, liquid nutrition is often very beneficial to the runner because it not only aids nutrient replenishment but also rehydration. As a general rule, runners should aim at sipping on 20-24 ounces of a sports drink for every pound of body weight lost post workout. Choose sports drinks containing carbohydrate, protein, and electrolytes (sodium, potassium, magnesium, calcium) to ensure optimal replenishment of nutrients.

The Longer Phase

The longer phase encompasses a period of time extending 20 hours following a workout and is designed to tap off glycogen stores and repair damaged muscle tissue. Because glycogen replenishment only occurs at a rate of about 5-7% per hour, full reestablishment of glycogen stores following a glycogen-depleting bout of exercise takes at least 20 hours. Therefore, athletes should aim at consuming smaller portions of carbohydrate mixed with protein every 2-3 hours during the 20 hours proceeding a glycogen depleting workout. Ultimately, the goal is to consume approximately 4 grams of carbohydrate per pound of lean body weight before the next significant training session begins.

Beyond consumption of carbohydrates, protein, fluids, and electrolytes post-workout, there is also increasing evidence that high consumption of particular nutrients, including antioxidants and Branch Chained Amino Acids (leucine, valine, isoleucine) may be beneficial for muscle recovery.

Antioxidants: Vitamins C and E are potent antioxidants that may help to protect our cells and tissues (including muscle) by working to neutralize the damaging effects of free radicals (by-products of strenuous exercise, pollution, smoke, chemicals in food, etc.). Vitamin C, which is a water-soluble vitamin, also seems to blunt the release of cortisol, a catabolic hormone, especially during high intensity or prolonged training. In fact, one study of 100 ultramarathoners who supplemented with 1,000 mg of vitamin C in the 7 days leading up to a 90k race exhibited 30% lower cortisol levels and consequent muscle tissue breakdown post-race.12 Similar to Vitamin C, Vitamin E also seems to reduce muscle damage. One study yielded a significant reduction in exercise-induced muscle damage in athletes doing a lot of downhill running when daily supplementation with 1,000 IU of Vitamin E was implemented.13 While research is still preliminary, there are some promising studies that suggest that consuming supplemental doses of antioxidants could reduce post-workout muscle tissue damage, speed recovery, and boost immune function. In addition, high intake of whole foods, including fruits, vegetables, and whole grains, will help enhance this antioxidant protection.

Branch Chained Amino Acids (BCAA): Branched chain amino acids (leucine, isoleucine,valine) serve as precursors for the synthesis of both glutamine and alanine, two amino acids that are used in large quantities during prolonged high intensity training. In fact, during extended exercise, BCAA may supply up to 15% of the muscles’ energy needs. Theoretically, intake of BCAAs will provide needed energy and help protect against muscle protein breakdown. Recent research has put this theory to the test. In one study, one group of cyclists were administered a BCAA supplement, another group a placebo, for 2 weeks preceding a 2 hour cycling bout. Both groups displayed elevated levels of biomarkers indicative of muscle damage for several hours to days following the cycling bout, yet the damage was substantially lower amongst the BCAA group.14 While both whey and soy protein naturally contains a high percentage of BCAAs, some researchers believe a combination of whey or soy protein isolate with Branch Chained Amino Acids (BCAA) seems to help improve muscle endurance as well as aid muscle recovery. Daily dosing patterns in research have ranged from 4-16grams with BCAAs.

Glutamine: As the most abundant amino acid within the blood and muscle cells, comprising more than 60% of the free amino acid pool in muscle tissue, glutamine helps to maintain a positive nitrogen balance in muscle tissue. Because levels of glutamine within blood and muscle cells fall during strenuous exercise, scientists believe that glutamine may halt some of the muscle breakdown that occurs during strenuous exercise, especially in overtrained individuals, making it a promising recovery nutrient. A daily dose of 2-8 grams of glutamine has been shown to help restore normal levels of this amino acid and enhance postexercise muscle recovery.15, 16

Summary

Nutrition is a well-supported contributor to optimal endurance performance as well as enhanced muscle recovery. To help stave off muscle soreness as you prepare for you next endurance event, be sure to 1) fuel with low-to-moderate glycemic carbohydrate and a smaller amount of protein before any prolonged or high intensity effort lasting 60-120 minutes, 2) refuel with 4-7:1 ratio of carbohydrate to protein during training lasting greater than 90-120 minutes, 3) use the 30 minute recovery window to replenish depleted glycogen stores and enhance muscle repair, aiming at a 4:1 ratio of high glycemic carbohydrate to protein, 4) , rehydrate with a sports drink, 5) continue refueling with carbohydrate and protein for the 20 hours proceeding a high intensity effort, and 6) consider use of potential muscle recovery aids, including antioxidants, BCAAs, and glutamine. Remember that these nutritional strategies only play a partial role with respects to recovery after intense exercise; it is also essential to taper back on your training intensity and/or duration for at least one day after a hard workout or race. If you find that your resting heart rate is consistently high, you may be overtrained, which will require a longer taper period before your body is physiologically ready to put forth the effort needed for peak performance.

As seen in Peak Running Performance (www.peakrunningperformance.com)

References

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2. Schabort, E.J., A.N. Bosch, S.M. Welton, and T.D. Noakes. The effect of a preexercise meal on time to fatigue during prolonged cycling exercise. Med. Sci. Sport. Exerc. 31: 464471, 1999.
3. Kirwan, J.P, D. Cyr-Campbell, W.W. Campbell, J. Scheiber, and W.J. Evans. Effects of moderate and high glycemic index meals on metabolism and exercise performance. Metabolism. 50(7): 849-855, 2001 Jul.
4. Chandler R.M., H.K. Byrne, J.G. Patterson et al. Dietary supplements affect the anabolic hormones after weight-training exercise. J Appl Phys. 76:839-45, 1994.
5. Zawadzki K.M., B.B. Yaspelkis, J.L. Ivy. Carbohydrate-protein complex increases the rate of muscle glycogen storage after exercise. J Appl Phys. 72, 1854-9, 1992.
6. Carli G, M. Bonifazi, L. Lodi et al. Changes in exercise-induced hormone response to branched chain amino acid administration. Eur J Appl Phys. 64: 272-7, 1992.
7. Res, P., Z. Ding, M.O. Witzman, R.C. Sprague and J. L. Ivy. The effect of carbohydrate-protein supplementation on endurance performance during exercise of varying intensity. Int J Sports Nutr Exerc Met. (In press.)
8. Niles ES, T. Lachowetz, J. Garfi, W. Sullivan, J.C. Smith, B.P. Leyh, S.A. Headley. Carbohydrate-protein drink improves time to exhaustion after recovery from endurance exercise. J Exerc Phys. 4(1):45-52, 2001.
9. Biola G., K.D. Tipton, S. Klein, et al. An abundant supply of amino acids enhances the metabolic effect of exercise on muscle protein. Am J Phys. 273: E122-E119, 1997.
10. Levenhagen D. L. et al. Post-exercise nutrient intake timing in humans is critical to recovery of leg glucose and protein homeostasis. Am J Phys, Endocrin Met. 280: E982-E993, 2001.
11. Van Loon, L. J. et al. Plasma insulin responses after ingestion of different amino acid or protein mixtures with carbohydrate. Am J Clin Nutr. 72:96-105, 2000.
12. Thompson, D., C. Williams, S.J. McGregor, et al. Prolonged vitamin C supplementation and recovery from demanding exercise. Int J Sport Nutr Exerc Met. 11: 466-481, 2001.
13. Sacheck, J.M, P.E. Milbury, J.G. Cannon, et al. Effect of vitamin E and eccentric exercise on selected biomarkers of oxidative stress in young and elderly men. Free Rad Biology Med. 34: 1575-1588, 2003.
14. Coombes, J.S., L.R. McNaughton. Effects of branch-chained amino acid supplementation on serum creatine kinase and lactate dehydrogenase after prolonged exercise. J Sport Med Phys Fitness. 40: 240-246, 2000.
15. Castell, L.M., E.A. Newsholme. The effects of oral glutamine supplementation on athletes after prolonged, exhaustive exercise. Nutr. 13: 738-742, 1997.
16. MacLennan, P.A., R.A. Brown, M.J. Rennie. A positive relationship between protein synthetic rate and intracellular glutamine concentration in perfused rat skeletal muscle. FEBS Letters. 215: 187-191, 1987.

Kimberly J. Mueller, MS, RD is a Registered Sports Dietitian and competitive endurance athlete who provides nutritional coaching and meal planning to athletes all around the world. More information on Kim’s services can be found at www.kbnutrition.com . Kim can be reached at kim@kbnutrition.com