Jan 29, 2015The Better to Heal You With
The latest research shows that certain dietary changes during rehab can help athletes control inflammation, heal more quickly, and get back into the game sooner.
By Dr. John Berardi & Ryan Andrews
John Berardi, PhD, CSCS, is an Adjunct Professor at the University of Texas and is trained in exercise physiology and exercise nutrition. He is also the President of Precision Nutrition. Ryan Andrews, MS, MA, CSCS, RD, LDN, is Director of Research for Precision Nutrition. To contact both authors and to read their nutrition blogs, go to: www.precisionnutrition.com.
When an athlete is injured, they’re usually eager to follow any protocol or strategy that promises to speed up the rehab process. They’ll use specialized weightroom plans, come in for therapeutic massage, and try innovative modalities like light therapy or underwater training if they think it will hasten their return to action.
But one area that’s often overlooked is the rehabbing athlete’s diet. A growing body of research reveals that the consumption of certain types of foods, supplements, and even spices can influence how the body responds to inflammation and repairs tissue. That may sound surprising, but it makes sense–after all, food provides the building blocks for cells and influences the messages sent throughout the body to regulate blood flow, tissue replacement, and healing.
While many questions remain, there is now enough information to draw some meaningful conclusions about how eating habits influence rehab and recovery. In this article, we’ll break down the research findings and translate them into suggestions for helping injured athletes eat their way back from injury.
Most athletic injuries follow a consistent pattern of healing that includes three stages: inflammation, proliferation, and remodeling. As researchers have developed a better understanding of the mechanisms involved in each stage, they have identified some stage-specific physical needs for which diet plays an important role.
The initial stage, inflammation, remains the subject of considerable debate. We don’t know exactly how inflammation aids the healing process, but it’s generally thought to be helpful unless it’s so excessive that it causes further tissue damage. The most common theory is that increased blood flow brings extra white blood cells to the injured area, thereby jump-starting the rebuilding of tissue.
During the post-injury inflammation period, which typically lasts four to five days for soft tissue injuries and up to three weeks for bone injuries, research has shown that dietary fat is a key factor. We now know that a diet high in trans-fats, omega-6 rich vegetable oils, and saturated fat promotes inflammation, while a diet high in monounsaturated fats and omega-3 fats inhibits inflammation. In addition, a diet that provides an equal balance of saturated, monounsaturated, and polyunsaturated fats (about one-third each) has been found to promote a healthy inflammatory response.
What does this mean for an injured athlete? Because injury leads to a natural inflammatory response, a diet that further enhances inflammation should be avoided. Research suggests it’s a good idea for athletes to decrease their omega-6 intake and increase omega-3 intake post-injury to help manage inflammation. A high omega-3 to omega-6 ratio has also been found to increase collagen deposition, further promoting healing.
In terms of practical advice, some study authors recommend that injured athletes, especially during the inflammation stage, consume anywhere from three to nine grams of fish oil per day because of its high omega-3 content (good choices include salmon oil, sardine oil, menhaden oil, and krill oil). Omega-3 rich foods, such as flax seeds and flax seed oil, walnuts, hemp seeds, perilla oil, salba, green leafy vegetables, salmon, sardines, and other oily fish are also recommended.
At the same time, the athlete should scale back on omega-6 in the diet, which comes mainly from vegetable oils such as corn oil, sunflower oil, safflower oil, cottonseed oil, and soybean oil. These oils are frequently used in crackers, potato chips, and other snack foods, and can also be found in meat from corn-fed animals.
In addition, research has shown that increased consumption of nuts, seeds, and olive oil can mildly reduce inflammatory biomarkers. These foods contain compounds known to reduce COX enzyme activity, giving them an effect similar to ibuprofen. However, it’s worth repeating that some degree of inflammation is beneficial after injury, so any dietary increase in these foods should be moderate at most.
When it comes to fat balance, an easy strategy for approaching a 1:1:1 ratio of saturated, polyunsaturated, and monounsaturated fats is to balance the saturated fat naturally present in many protein-rich foods with unsaturated fat-containing foods like olive oil, mixed nuts, avocados, flax seed oil, ground flax, and other seeds. However, to avoid unwanted weight gain, athletes should be careful not to overindulge in these fattier foods, especially if their activity level has decreased because of injury.
Certain spices and phytochemicals can also affect an injured athlete’s inflammation response. For details on which ones and how they work, see “Natural Anti-inflammatories” below.
After the inflammation stage, the focus of rehab nutrition shifts and energy intake becomes a top priority as the body begins its proliferation and remodeling processes. When an athlete is healthy, energy needs are obviously high due to their activity level. After an injury, athletes often feel tempted to drastically reduce energy intake–they might believe that restricting calories is the only way to avoid unwanted weight gain, or they might simply not feel as hungry because they’re less active. But energy needs are quite high while the body repairs itself, mainly because of post-injury hormonal changes and the physical requirements of new tissue formation.
Specifically, basal metabolic rate (BMR) may increase by 15 to 50 percent after injury, depending on the severity of the trauma. Most injuries and minor surgeries raise BMR by 15 to 20 percent, while major surgery may lead to a 50 percent increase.
When trying to determine energy needs during recovery, it’s important to consider this increased demand. Here is an example of how to calculate appropriate energy intake:
Male, 19 years old, 5’9″, 180 pounds
Basal Metabolic Rate:
1,826 kcal/day (based on the mean of three predictive equations).
Energy needs when sedentary:
2,191 kcal/day, based on activity factor of 1.2 (BMR x 1.2).
Energy needs with daily training:
3,104 kcal/day, based on activity factor of 1.7 (BMR x 1.7).
Energy needs post-injury:
2,629 kcal/day, based on activity factor of 1.2 and a 20 percent increase in metabolism due to injury recovery (BMR x 1.2 x 1.2).
Thus, while optimal energy intake during recovery is lower than during full activity, an athlete will be underfueling if his or her intake does not account for the physical needs associated with injury repair. Depending on their post-injury activity level, an athlete’s appetite may decrease significantly, but they must be encouraged not to undereat, as this can slow the rehab process and lead to other unwanted effects, such as loss of lean body mass.
During the proliferation and remodeling stages, macronutrients also play a key role. And not surprisingly, protein is one of the most important.
The standard clinical recommendation for protein intake in healthy individuals is 0.8g per kilogram of body weight per day. As the body repairs damaged tissue, protein is extremely valuable, so research indicates that rehabbing athletes should strive to eat at least 2.0g per kilogram of body weight per day.
The carbohydrate picture is quite a bit cloudier. It’s well established that glucose is necessary for injury repair, and consistent carb intake also helps to stabilize insulin concentration in the bloodstream, which may impact wound healing. But no specific carb recommendations have yet been established for post-injury periods. At this point, the best strategy is simply to make sure athletes are not consciously restricting their carbs for weight loss or any other reason.
Role of Micronutrients
In all stages of injury recovery, vitamins A, B, C, and D, as well as calcium, copper, iron, magnesium, manganese, and zinc can play vital supporting roles. (Interestingly, research suggests vitamin E may slow healing, so it should be avoided during rehab.) However, the research isn’t clear on exactly why all these micronutrients are helpful. For that reason, we will limit this discussion to those that are best understood and most likely to require supplementation in an injured athlete’s diet.
Vitamin A supports early inflammation after injury, and helps reverse post-injury immune system suppression. It also assists in collagen formation, and studies have shown that supplementation strengthens collagen cross-linkage and speeds repair. Typically 25,000 IU (international units) daily is recommended during short periods after serious trauma or surgery, but continuing this dose for too long can lead to toxicity, so it’s wise to consult a physician. With sports injuries, supplementation with 10,000 IU daily for the first one to two weeks post-injury provides a safe level that may enhance healing but will not lead to vitamin toxicity.
Vitamin C enhances neutrophil and lymphocyte activity during the inflammation phase, and also plays an important role in collagen synthesis as it assists in the formation of bonds between strands of collagen fiber. With vitamin C deficiencies, collagen fibers are formed abnormally and fibrous tissue is weak with poor adhesion. In addition, vitamin C acts as a powerful antioxidant and immune system modulator. For these reasons, research suggests that supplemental vitamin C can be beneficial after surgery or injury. One to two grams per day is the typical recommended dose, but only for limited time spans–if this dose is continued long-term, side effects like diarrhea and gastrointestinal disturbances may result.
Copper is a mineral that assists in the formation of red blood cells and acts in concert with vitamin C to form elastin and strengthen connective tissue. Two to four milligrams per day is recommended during the first few weeks of injury repair.
Zinc is required for over 300 enzymes in the body and plays a role in DNA synthesis, cell division, and protein synthesis, all of which are necessary for tissue regeneration and repair. Zinc deficiency has been associated with poor wound healing, and since it is one of the most common micronutrient deficiencies, supplementation of 15 to 30 milligrams per day is recommended, especially during the initial stages post-injury.
Besides all these, supplemental amino acids may also exert powerful effects on healing, primarily by speeding up the tissue repair process. In one study, the combined administration of 14g arginine, 3g HMB, and 14g glutamine in two divided doses for 14 days significantly increased collagen synthesis in adults. However, most of the research on this application of amino acids has studied elderly or hospitalized subjects, so the relevance of these findings to the athletic community is unknown. Still, there is some evidence that arginine, HMB, and glutamine in particular play a role in healing by stimulating collagen deposition.
The take-home message for injured athletes when it comes to the entire family of micronutrients is this: With the exception of vitamin E, moderate supplementation of key vitamins and minerals may significantly aid the rehab process. Because vitamin A, vitamin C, and multivitamin supplements are inexpensive and safe if used properly, they are a responsible addition to any post-injury nutrition strategy.
So how do you turn all this information into real meal solutions for rehabbing athletes? Try having them follow these dietary guidelines when recovering from an injury.
Frequency: Eat every two to four hours.
Protein: Each meal should contain complete protein, including lean meats, lean dairy, eggs, soy products, or a protein supplement if whole food is not available.
Vegetables and Fruit: Each meal should contain one to two servings of vegetables and/or fruit.
Starches: Additional carbohydrates should come from whole grain, minimally processed sources like whole oats, yams, beans, whole grain rice, or quinoa. Athletes can slightly reduce their intake from this category during rehab, and eat more as soon as they return to active training.
Fats: Athletes should choose from among these “good” fats each day to promote a healthy balance of fat types: avocadoes, olive oil, mixed nuts, flax seeds, and flax oil. In addition, three to nine grams of fish oil should be added to their daily diet.
Supplementation: A multivitamin or other vitamin tablets can be used to supplement micronutrient intake. Natural supplements with anti-inflammatory properties (such as garlic extract, turmeric extract, or bromelain) can also be considered, but should always be used with caution. (See “Natural Anti-inflammatories” below for more information.)
It may have occurred to you that many of the nutrition strategies discussed in this article would be sound advice whether an athlete is injured or not. And you’re right. Biological needs change somewhat when the body is repairing itself and recovering from injury–especially during the inflammation stage. But for the most part, good nutrition is good nutrition.
You’ve probably observed many athletes who could stand to improve their dietary habits. In most cases, the rehab process provides a great opportunity to address nutrition with these individuals. After an injury, athletes are more focused on their physical needs and interested in anything that can help get them back onto the field, court, rink, or track. When they see the benefits of improving their nutritional profile, they may end up changing their habits for the long run.
Sidebar: Natural Anti-Inflammatories
Certain dietary herbs can be very beneficial in the first stage of injury recovery. By adding them to an athlete’s diet, you can do a lot more than spice up their entrees–you can help them control post-injury inflammation and decrease (or possibly even eliminate) their dependence on anti-inflammatory drugs such as NSAIDs.
Turmeric, a flowering plant in the ginger family and a common ingredient in curry powder, has long been used as an anti-inflammatory agent and in wound healing. Current research shows that its active ingredient, curcumin, is at least partially responsible for these effects. While adding curry powder to an athlete’s diet after injury is likely a good strategy, a turmeric extract supplement will have a greater effect because it provides a daily dose that even the most die-hard curry fans would find unpalatable in food.
Garlic has been shown to inhibit the activity of two inflammatory enzymes, cyclooxygenase and lipoxygenase. It also affects the function of macrophage cells, which help clear dead tissue from inflammation sites. Like with turmeric, adding more garlic to an athlete’s diet can be helpful, but supplementation will provide the most noticeable results. The typical recommended dosage is two to four grams of whole garlic clove each day (each clove is about one gram) or 600 to 1,200mg of aged garlic extract.
Bromelain is another anti-inflammatory plant extract. It’s found in pineapple, and while best known for its digestive properties, it is an excellent anti-inflammatory and analgesic compound. It can be found in supplement form, and the typical dose for managing inflammation is 500 to 1,000mg per day.
Flavonoids (compounds found in cocoa, tea, fruits, vegetables, and legumes) can also help manage inflammation, primarily through their well-known antioxidant properties. These powerful substances have the added bonus of affecting cell growth and the development of new capillaries, both of which are important for tissue regeneration. Rehabbing athletes should be encouraged to eat more flavonoid-rich foods, especially fruits, vegetables, and legumes. If they’re not interested in these dietary changes, flavonoids can be found in supplement form, such as blueberry and grape extracts, green tea extracts, and bioflavonoid supplements.
It’s important to note that you should always be careful and very specific if you recommend supplement use to an athlete. Since most athletes are looking for any competitive edge they can get, they may interpret a harmless message about a food supplement as a tacit endorsement of other, potentially dangerous performance aids. Certain supplements may also contain ingredients that run afoul of substance use rules, particularly at the college level. If an athlete focuses on eating the right foods, supplementation should only be necessary if inflammation becomes a major or chronic problem, at which point any anti-inflammation strategy should be discussed with a physician.