I did a short Q&A for Functional Sports Nutrition in the July/August 2013 issue of their magazine, talking about nutrition for the injured athlete. It makes for quite a good blog post actually, even if I do say so myself.
What you will learn:
• The role of nutrition when injured
• Key nutrients and food groups that aid the rehabilitation process
• My recommendations based on the existing evidence
Who this is applicable to:
• Anyone involved in the preparation & treatment of humans
• Injured people
Who should not read this:
• Sedentary people immune to injury
Enjoy, and please leave feedback. I am open to critique, it is the only way I will ever improve as a practitioner, coach, and as a person.
Q: Hi Matt, do you think there is a particular nutritional strategy that can protect an individual from experiencing injury?
MJ: Unfortunately no nutrient provides absolute protection from injury, although if an athlete ensures optimal health by meeting daily requirements they reduce the likelihood of injury. Avoiding training weak body parts or undertaking skilled tasks while glycogen-depleted can also decrease the likelihood of injury. Chronic calcium deficiency is a major cause of reduced bone mass so ensuring adequate dietary calcium is critical in reducing bone injury. Good dietary sources of calcium include Dairy Products, Chinese cabbage, Kale and Broccoli; although oxalates present in green vegetables can form insoluble complexes with calcium which reduce absorption. For this reason, milk and dairy products are by far the best dietary source of calcium – cow’s milk contains an average of 1.2g calcium per litre. Further, evidence suggests that milk can provide calcium with “ensured absorbability”.
Three calcium-rich foods each day should adequately meet an individuals daily requirement of calcium. That said, even optimal bone health will not provide absolute protection from a force that is significant enough to break a human limb.
Q: The use of anti-inflammatories as an injury treatment in sport is popular; is this something that you would recommended?
MJ: The acute inflammatory stage of an injury is quite problematic; it involves a cascade of biochemical events, redness, swelling, heat, pain and a loss of function which all allow for the clearance and removal of the injured tissue. A degree of inflammation is necessary as it is a natural stage in the recovery process, although it is important to manage it because prolonged inflammation can slow recovery. The use of anti-inflammatories is therefore not advisable, although ensuring sufficient dietary omega-3 fatty acids are being consumed is crucial in managing the inflammatory profile.
Q: If an athlete is injured and out of action for training, how would you adjust their nutritional intake?
MJ: Owing to the limited availability of information in this area it is difficult to make precise recommendations, although there are some suggestions that BMR can increase by as much as 30% in the immediate aftermath, and can remain elevated by 5 – 20% for the duration of injury. It is vital that the body receives sufficient energy (kcal) to allow for the recovery of tissue, failing to meet energy needs initiates further catabolism, further depresses the immune system and may exacerbate inflammation, ultimately retarding the recovery process. On the other hand, exceeding daily energy requirements, which is often the case given the reduced activity levels can also cause issues. Calculating individual requirements is essential, especially given the increased BMR and reduced activity levels; inactivity will generally reduce carbohydrate requirements.
Q: Which nutrients play a vital role in the recovery from injury and where are the best places to get them?
MJ: The specific benefit of certain nutrients on the healing process is difficult to determine given the multi-factorial nature of the human diet, obviously meeting daily energy requirements is essential. Beyond this base, adequate protein intake is essential in counteracting the increased catabolism. Vitamin C is involved in collagen synthesis and plays a fundamental role in immune function which is important in injury repair, Oranges, Red Bell Peppers and Broccoli being rich in this Vitamin. Vitamin A plays an integral part of the healing process, especially cell growth, and also supports the immune function, Spinach Carrots and Sweet Potatoes are good sources. Zinc is also involved in wound healing, Meat, Seafood and Almonds are all zinc rich.
Research has highlighted an association between vitamin D and increased immunity, studies are currently underway to determine the precise mechanisms, but until then ensuring vitamin D sufficiency is paramount during injury offering the added benefit of enhanced absorption and utilisation of calcium and phosphorus which both support bone health. When looking at specific foods to provide key nutrients during injury you would be hard pressed to find anything better than Milk and Dairy products.
Q: Are there any supplements that can aid or enhance recovery from an injury?
MJ: Again, the limited available data in the area makes it difficult to give recommendations – to my knowledge there are no systematic reviews or meta-analyses and only a limited number of clinical trials. Most of the available data deals with wound healing and the sparse data in the area of bone healing suggests that nutritional adequacy and sufficient blood flow is the only way to heal a bone. Arginine has a regulatory role in wound healing since it enhances nitric oxide synthesis which is associated with wound healing. Nitric oxide synthesis is reduced with malnutrition, especially protein malnutrition – again highlighting the necessity of meeting daily protein requirements. Arginine and the aforementioned micronutrients should be provided through a well balanced diet, with supplementation a secondary consideration.
Q: Can you please comment on the important anabolic metabolic process during injury recovery and how to support it through nutrition and lifestyle.
MJ: Anabolic metabolic processes are necessary to maintain protein synthesis, which is responsible for maintaining lean body mass, attenuating muscle disuse atrophy and wound healing. Production of anabolic hormones is reduced following illness or injury, the stress response increasing catabolic hormone activity which can significantly increase tissue breakdown and reduce the anabolic activity required to preserve lean mass and maintain the healing process. The stress response to injury alters the protective protein sparing process which is seen in normal starved states, the increased activity of catabolic hormones results in an increase in the diversion of dietary protein from the protein synthesis compartment to energy production compartment. Energy production from dietary protein can increase to around 25%, from a normal figure of 5%, causing protein energy malnutrition to evolve rapidly. In reality, only anabolic steriods can significantly modify this natural hormonal reaction, although to effectively support anabolic hormonal processes adequate calories and protein must be provided.