Injuries happen, from tripping on a curb and spraining an ankle, pulling a hamstring during a game of football, to suffering a knee injury such as an anterior cruciate ligament tear. Injuries may happen to anyone but are more common in individuals who engage in a regular physical activity and specifically those who play or compete in sports.
Scandinavian studies show that sports injuries account for 10-19% of all acute injuries seen in accident and emergency rooms with the majority of injuries occurring from sports like football, basketball, volleyball and hockey. Other injuries requiring treatment include burns, ulcers and pressure sores.
Risk factors for injury
Risk factors include; ageing, gender, body composition, history of previous injury, current physical fitness, skill levels as well as external factors such as weather conditions and potential protective equipment such as pads and guards.
Poor nutritional status may also be considered a risk factor for injury. For example, nutritional deficiencies such as calcium and vitamin D that may contribute to reduced bone density can make people more prone to breaks and fractures. This is more common in the elderly. Other common micronutrient deficiencies among the elderly include zinc and vitamin B12 which may have a significant impact on wound healing.
Low protein and low-calorie diets may result in poor nutritional status; this is also more commonly seen in elderly nursing home populations.5 Poor wound healing may occur in persons with diabetes as a result of a lack of blood flow to the area due to diabetic neuropathy.
Almost any part of the body can be injured, including bones, muscles, joints and connective tissues (tendons and ligaments). Ankles and knees appear to be particularly prone to injury.
Signs of injury
Pain in the area is the most common and obvious sign of injury, whether this is sudden or comes on afterwards, as well as tenderness, bruising, swelling and stiffness or restricted movement of the area. While it might be tempting to keep playing, or finish a game, continuing to exercise through injury may cause further damage and slow recovery time. Provided you do not require more intensive medical treatment such as stitches, or x rays, NHS advice is to use PRICE therapy at home (“Sports injuries – Treatment – NHS.UK”).
P – Protect the area from further injury, for example using a support or splint.
R – Rest as much as possible for two days following the injury. Avoid putting weight on the area.
I – Ice, apply a covered ice pack to the area for 10 minutes and repeat regularly over 48 hours.
C – Compression of the area, ideally using a snug (but not tight) medical bandage.
E – Elevation, trying to keep the area raised when you’re not icing the injury.
While PRICE is useful in the initial instance, could there be further, more targeted nutritional and supplementary approaches to aid recovery and support repair?
Firstly we need to understand what happens immediately after an injury and the stages of repair.
Soft Tissue Repair happens in several phases
Phase 1 – The initial response to an acute injury is inflammation, and haemostasis, the aim being to control cellular damage and blood loss, clear debris from the site, and try to prevent and control invading bacteria. This phase may last up to 4 days from the time of injury and includes vasoconstriction to eventually stop bleeding and form a clot. The injury may look red and swollen during this phase and feel warm to the touch.
Phase 2 – Proliferation. New blood vessels are formed, fibroblasts produce collagen, wound edges start pulling together, and the wound is covered in a new layer of epithelial tissue. This process may start around day three after injury and continue for up to 2-3 weeks.
Phase 3 – Remodelling. Collagen and other proteins become more organised in structure, and a stronger type II collagen replaces type I. This phase can take up to 2 years to be complete. Scar tissue may be only 70-80% as strong as previous tissue.
Bone Repair also happens in stages
Stage 1 – Reactive phase inflammation
Bleeding from the fractured bone and surrounding tissue causes the fractured area to swell. This is similar to the inflammation phase experienced in soft tissue injury.
Stage 2 – Soft callus formation
Pain and swelling decrease. The site of the fracture will stiffen, with new bone forming. New bone is weaker than uninjured bone, it is also not complete and cannot be seen on x-ray.
Stage 3 – Hard callus formation
New bone begins to bridge the fracture during this phase, covering the incomplete soft callus. This bridge can be seen on x-rays.
Stage 4 – Bone remodelling
The fracture site remodels itself, correcting any deformities that may remain as a result of the injury. This final stage of fracture healing can last several years.
What can be done to support healing with nutrition?
While it might be tempting to have a few days on the sofa eating pizza and ice cream, ensuring a balanced ratio of macronutrients and using specific foods and nutrients may reduce recovery time and support healing. Research suggests that the therapeutic usage of certain nutrients in dosages above the Government’s recommended intakes (i.e. nutrient reference values – NRV) may help wounds to heal5.
Proteins are fundamental structural components of all cells and tissues and are required for repair. During phase 2 of repair when new tissue is being created and laid down, protein requirements increase. Depending on the type of injury, large amounts of protein may be lost each day. The presence of a chronic wound (such as a pressure ulcer) may increase protein requirements by as much as 250% and calorie requirements by 50% to preserve lean body mass.
The British Nutrition Foundation recommends a daily protein intake of 0.75g/kg body weight for healthy adults, and there have been suggestions for differing protein amounts depending on the type of injury (“How dietary protein intake promotes wound healing – Wound Care Advisor,”).
1 – 1.5g protein/kg although this may vary depending on the extent of the surgical wound
1 – 1.5g protein/kg although those with deep ulcer sites or multiple pressure sores may need close to 2g protein/kg.
Large burn wounds may require 1.5 – 3g protein/kg
Injured athletes may require 1.5-2.0 g protein/kg. To ensure a quick recovery, this higher protein intake would likely need to be consumed consistently. At a minimum, injured athletes would be best to aim for 1 g of protein per pound of body weight.
While there are variations in protein requirements depending on the injury, it would be wise to ensure your intake following injury is adequate. Eating a source of good quality protein such as egg, meat, poultry or high protein dairy such as whey, yoghurt or cheese at each meal should suffice. Vegans would likely need to ensure a combination of sources such as tofu, plant-based protein powders, legumes and nuts and seeds to ensure they consume an adequate amount.
Specific Amino Acids
Collagen is the most abundant protein in the body and helps compose the extracellular matrix. Over 20 different types of collagen have been identified in humans, the most abundant being types I, II and III which make up 80% of the body’s collagen. In repair phases 2 and three collagen is produced and laid down. More recent research has focused on whether collagen may have a role to play in topical application, such as the use of dressings.
Eating a diet rich in protein, particularly in connective tissues, from animal products and using homemade bone broth may support collagen requirements. However, the body is capable of synthesising its own collagen provided you have enough lysine, methionine (essential amino acids that must be obtained via dietary protein), vitamin C, zinc and copper.
Arginine and glutamine may also be beneficial for tissue repair. Arginine stimulates insulin release and Insulin Growth Factor action. These are anabolic hormones which increase protein synthesis and collagen deposition. Glutamine is an amino acid essential for the metabolism of rapidly turning-over cells such as lymphocytes and enterocytes. During injury, glutamine needs an increase. Glutamine has been hypothesised but not yet conclusively proven to speed up wound healing. However, some studies showed that combining arginine and glutamine as supplements for two weeks did significantly increase collagen synthesis in adults.
Bone Healing Support
Vitamin D, calcium, boron, magnesium and vitamin K are all essential nutrients for bone repair and remodelling.16 As these nutrients may be lacking, due to low dietary intake and, in the case of vitamin D insufficient sun exposure, they may be supplemented for those with bone injuries, and potentially in older populations or those in high-risk groups for bone injuries.
Soft Tissue Support
Cartilage tears, cuts and sprains may benefit from the use of glucosamine, especially when paired with an omega three fatty acid.
Glucosamine is an important basic natural component of cartilage and synovial fluid. It is naturally formed by the body, but can also be found in food. More commonly used in cases of arthritis, its role in soft tissue support may help strengthen connective tissue, increase synovial cells to improve the viscosity of synovial fluid, which may prevent ligament tears and support new tissue being laid down after injury.
MSM (methylsulphonylmethane) is an organic form of sulphur with a range of biological effects. High levels of sulphur are found in the muscles, skin and bones as well as concentrated amounts in the hair and nails. Sulphur is a component of keratin, collagen and elastin, providing flexibility, tone and strength to muscles, bones, joints, skin as well as hair and nails.
Inflammation itself is a useful and necessary part of healing, therefore rushing to combat inflammation in the first instance may be counterproductive. However for longer-term recovery, once the inflammatory phase is over, further support may be required to keep on going and/or chronic inflammation under control.
Having a diet rich in omega-3 fatty acids from fish, flaxseed and vegan algal sources and monounsaturated fats like olive oil, and low in trans fats, and omega-6 rich vegetable oils such as sunflower and canola, may help support a healthy balanced inflammatory profile. High omega 6:3 ratios may reduce collagen production required for repair, whereas a low 6:3 ratio may support repair. Dosages of between 1-3g of omega-3 fatty acids daily have been shown to improve repair time to blister injury.
However, most of the benefits in wound healing were in the group who had taken fish oil for four weeks before an injury. This may support the case for regular daily consumption of fish or an omega-3 product for overall health and to support tissues in the event of injury.
Other phytochemicals with anti-inflammatory actions include turmeric (curcumin), garlic, bromelain (from pineapple), Boswellia and flavonoids.
Ensure the diet is rich in the following foods:
- Pineapple and Papaya (although care on quantities as also high in sugar)
- Cocoa (unsweetened)
- Turmeric – fresh or dried
- Green Tea
- Rosemary and Sage
Vitamins A, B, C, and D as well as the minerals calcium, copper, iron, magnesium, manganese, and zinc are all important for injury recovery.
Vitamin A has been used topically for the repair of several skin conditions such as acne, psoriasis and sun damage, and has been shown to stimulate epithelial growth as well as provide anti-inflammatory effects in open wounds. Studies are not conclusive for the optimal doses of vitamin A but suggest it may be between 10,000 – 20,000IU per day. Vitamin A above 5,000IU may cause birth defects and cause liver damage if taken prolonged so we would not recommend high dose vitamin A intake without supervision from a healthcare professional.
The amount of vitamin C required for wound healing varies, but research suggests that for small wounds or pressure ulcers 500 – 1000mg daily in divided doses is optimal. More severe wounds, such as large burns, may require closer to 1-2g of vitamin C per day.
Zinc is required for the production of over 200 enzymes including those required for wound healing, antioxidant function, cell replication and tissue repair. Zinc supplements of up to 30- 40 mg/day for up to 10 days after injury may enhance wound healing.
Poor nutritional status is a risk factor for injury. For example, nutritional deficiencies such as calcium and vitamin D that may contribute to reduced bone density can make people more prone to breaks and fractures. Other common micronutrient deficiencies include zinc and vitamin B12 which may have a significant impact on wound healing.
Protein needs increase considerably following significant injury and requirements vary depending on the injury. Eating a source of good quality protein such as egg, meat, poultry or high protein dairy such as whey, yoghurt or cheese at each meal should suffice.
Collagen is a protein that helps compose the extra-cellular matrix. The body is capable of synthesising its own collagen provided you have enough lysine, methionine (essential amino acids that must be obtained via dietary protein), vitamin C, zinc and copper
Glutamine is an amino acid essential for the metabolism of rapidly turning-over cells such as lymphocytes and enterocytes. During injury, glutamine needs an increase. Glutamine has been hypothesised but not yet conclusively proven to speed up wound healing.
Vitamin D, calcium, boron, magnesium and vitamin K are all essential nutrients for bone repair and remodelling. Glucosamine and MSM are useful for soft tissue support. Vitamins A, B, C, and D as well as the minerals calcium, copper, iron, magnesium, manganese, and zinc are all important for injury recovery.