The goal of any coach or athlete is to prevent injury in the process of improving performance, however, occasional injuries are almost unavoidable at some point in an athletic career. While there is a plethora of great advice on exercises and modalities of exercise out there for rehab, it may be hard to understand how your nutritional demands change with injury. Today, we are going to discuss nutrients essential to the healing process and some practical ways you can use nutrition to optimize your recovery and get back to improving your performance again.
To fully understand nutrition for an injury, you must first understand the bodies response to an injury which can be broken down into four phases:
1.) Hemostasis: While complicated to say, the meaning of hemostasis is found in its name, Heme – meaning blood and Stasis – meaning to yield. This is a short lived phase in which the blood vessels around the injury constrict to slow the flow of blood to the area, platelets come into the area and form what is known as a platelet plug and than a clot forms.
2.) Inflammatory Phase: This is the phase most of us are most familiar with. The inflammatory phase is associated with increased permeability of the blood vessels around the injury leading to swelling and warmth as the body shuttles immune cells to the wound to combat infectious pathogens that may be present at the site of the wound during the early phases. They also assist with the repairing of tissue through the release of growth factors later in the inflammatory phase. While our first reaction to this phase is to try to eliminate the inflammation, a certain amount of inflammation is vital to the healing process. That being said, we can try to manage the inflammation and prevent this phase from being longer than necessary due to nutritional deficiencies or re-injury to the wound.
3.) Proliferative Phase: This phase is marked by the creation of granular tissue which fills up the wound and is a rough framework of tissue to be remodeled into a more permanent tissue later. It is also marked by the formation of new blood vessels in the area around the wound. Maintaining proper collagen synthesis during this time is going to be critical in the health and strength of the new tissues being formed.
4.) Maturation Phase: This is the final phase of wound healing and is marked by the remodeling and reorganization of the tissues formed in the prior phase. During this phase, Type III Collagen is converted into Type I Collagen which is more durable. This phase can last up to two years following an injury with the newly reorganized tissues having between 40-70% of their prior strength by the forth week following the injury.
Now that we have covered the four main phases of the bodies response to an injury let us delve into how nutrition can effect each stage.
Energy Requirements: Following an injury, energy demands logically increase in the body as cellular metabolism is increased and the body is working hard to create new tissues. Depending on the severity of injury, energy requirements may increase 15-50%. To be noted, however, is that injuries often result in a reduction of physical activity as well which will decrease energy demands. The main point here is to not drastically reduce calories following an injury as, even though you are exercising less, energy demands are increased and without adequate energy the recovery process will be slowed leaving you incapable of returning to training and competitive play for longer. A slight reduction may be in order if you are much less mobile, however, if you are using crutches or training around your injury your energy demands may not be as reduced as you think. It is better to have slightly more calories than you need than not enough to provide for healing.
Protein: You can’t mention the building of new tissues and not talk about the importance of adequate protein intake. Suggested protein intakes for injury range from 1.2 – 1.5g/kg [3, 4] to >2.0g/kg/day. Protein ingestion on the higher end may provide for a reduction in muscle loss during times of reduced activity and decreased energy intake. Insufficient protein intake has been shown to reduce the synthesis of proteins, such as collagen, which is crucial during healing, especially during proliferation and maturation. That being said, it is not recommended to eat more extreme amounts of protein during this time. Although protein intakes as high as 4.4g/kg/day[7, 8] have been shown to be safe in healthy individuals, during times of injury there is an increased nitrogen load on your kidneys due to the break down of injured tissue and excessive protein may add additional stress. In other words, a slightly increased protein intake may be warranted during times of injury to maintain lean tissue and promote healing, but don’t be an idiot.
Carbohydrates: The main purpose of carbohydrates in the body is to provide energy, especially during times of high-intensity activity. With high-intensity activity being obviously reduced with an injury, carbohydrate requirements may not be as high. That being said, it is not suggested to go on a low-carb diet during this time as it has been shown that production of fibroblasts, the cells responsible for producing new tissue fibers, are sensitive to low blood sugar levels . Without adequate amounts of carbohydrates, the healing process may be slowed do to a lower production of these important cells. If worried about body composition, carbohydrate levels may be reduced accordingly with decreases in energy intake, however, they should still constitute a significant portion of your daily calorie intake.
Fat: Fats are finally starting to get respected again in our society, and for good reason. Healthy fats, especially the heart healthy Omega-3 fats are an important part of wound healing. Fats are important constituents of cell membranes, can reduce inflammation, enhance the immune response and help with the absorption of fat soluble vitamins that are necessary for the healing process. Healthy fat requirements have been shown to be increased during times of injury as well. Healthy dietary fats should constitute no less than 18% of your daily intake and are healthy in as high amounts as 30-35%.
Vitamins: Though increases in vitamin intake may not directly increase the rate of wound healing, deficiencies in vitamins, especially A,C,D and K, have been shown to significantly slow the rate of wound healing and reduce the integrity of newly formed tissues. While all are vital, of particular note are Vitamin A and Vitamin C:
- Vitamin A: Has been shown to increase the immune response during the early inflammatory phase by increasing the number of monocytes and macrophages, the warriors of the immune system, reaching the wound to remove bacteria and assist with the initial healing process. Vitamin A has also been shown to enhance the production of collagen and the differentiation of cells during the proliferation phase of healing. It is recommended to consume at least 25,000 IU of Vitamin A during an injury to promote healing and prevent deficiencies .
- Vitamin C: Vitamin C is an exceptional antioxidant and enhances the immune response during the inflammatory phase of wound healing and has been shown to increase collagen production and the production of new blood vessels[13, 14]. 1-2g of Vitamin C has been recommended during times of injury.
Minerals: Similarly to vitamins, deficiencies in minerals may lead to a reduced rate of wound healing and it is not uncommon for individuals, especially athletes, to be deficient in minerals such as zinc, magnesium, selenium, calcium and iron which are all important during wound healing. Of particular note is zinc which is required for the synthesis of DNA and new proteins and is an important cofactor in many metabolic processes.
Glutamine: Glutamine is a amino acid which is generally produced in the body in sufficient amounts during times of good health, but becomes “conditionally essential” during times of injury. Fibroblasts, those fancy tissue fiber making cells we talked about before, use glutamine to make new proteins as well as nucleic acids.
Collagen: Collagen supplements have been shown to have a number of benefits for the development of connective tissues including bones, tendons, ligaments and skin and have been shown to increase collagen production at the cellular level. If you are interested in learning more about collagen and its benefits, check out my prior post about it here.
Practical Applications: In more practical terms, many of these needs can be met through a well-balanced diet allowing for appropriate amounts of energy and focusing on whole foods, especially lean meats, dairy, fruits, vegetables and healthy fats.
- Eat about 1-2 palm sized portions of protein, such as lean meat, at each meal.
- Incorporate dairy such as milk, greek yogurt and cottage cheese to increase protein intake while also providing important nutrients such as calcium and Vitamin D.
- Space your protein intake evenly throughout the day for optimal healing.
- Add color to your plate with a variety of fruits and veggies; they are great sources of carbohydrates and the incorporation of a variety of them can greatly help you meet your vitamin and mineral needs. Shoot for 1-2 fist sized portions at each meal, but you can’t go wrong with more throughout the day.
- Eat healthy fats like olive oil, fish oil, avocado and nuts that provide the fats necessary for healing as well as important minerals like magnesium, selenium and zinc. Shoot for 1-2 thumb sized portions at each meal.
- Supplement with collagen and glutamine to further enhance your rate of healing.
The importance of nutrition during healing cannot be overstated, however, it doesn’t have to be complicated. Nature provides most of what we need.
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