TRAINING AND IMMUNITY

During periods of intense training or immediately following endurance race events, many athletes find that they are susceptible to minor respiratory illness, such as colds and sore throats. While moderate training seems to boost your immune system, prolonged periods of intense training appears to depress immune cell functions. There may be a certain window of decreased protection after these intense sessions, this means that you can be at more risk of viruses and bacteria which may develop an infection. It is thought that the increased levels of stress hormones, such as adrenaline and cortisol can inhibit the immune system (hindering its ability to protect you). But other simple stresses such lack of sleep, poor nutrition or perceived stress can depress immunity.
 
A healthy diet that meets your energy needs and provides enough micronutrients for your immune cell function will be very important. Iron, zinc, magnesium, manganese, vitamins A, C, D, E, B6, B12 and folic acid are among the most important for maintaining immune defences. This can all be obtained through diet, you do not have to supplement anything/everything, just make sure you get fresh air during sunlight hours alongside a good portion of varied fruit and vegetables every day. What can be very damaging to your immune system are diet periods or below maintenance calories while training at a very intense pace, even just a short-term diet can leave you very susceptible to infections. In saying that, people who train at a very intense level should be fine if they are controlling the controllable factors. Here are some tips on how to protect your immunity while you train hard.
 
Don’t under eat, especially if you’re training for performance (GAA). Match your calorie intake and expenditure as under eating will increase cortisol levels. Eat nutrient dense foods such as vegetables, fruit, whole grains, lentils, nuts and seeds. Avoid low carbohydrate diets as low glycogen stores are associated with bigger increases in cortisol levels and bigger suppression of your immune cells. Drink plenty of fluids to increase your saliva production; this contains anti-bacterial proteins that can fight off airborne germs. Make sure you get enough sleep every night to reduce stress (6-9 hours).
 
Supplements can be used to get that extra kick, but you should nail down the above before even looking to supplements. Vitamin C can help reduce the risk of upper respiratory tract infection and one study even showed that marathon runners who took daily vitamin C supplements (approx. 1500mg) seven days prior to a race had lower levels of stress hormones following the race, suggesting a greater protection against infections (study conducted by Peters, in 2001 in the University of Natal, Durban, South Africa). During intense exercise, glutamine can fall up to 20% which puts a strain on the immune system, so supplementing that may help also. Many other studies found that Probiotic supplements, Quercetin supplements and Echinacea supplements all helped to boost immunity, reducing the risk of catching a cold.