Fitness and exercise is on everyone's minds now with New Year's resolutions in full swing. In the northern hemisphere, New Year resolutions just happen to coincide with winter – a time when almost everybody seems to have the sniffles. Naturally exercise is associated with good health and well being, but is it possible that your workout or training program may actually increase your chance of getting sick? This article briefly explains the immune system, its response to exercise and offers some helpful tips on how to avoid getting sick if you exercise regularly.
What is the immune system?
Unlike our cardio-respiratory or digestive systems which are made up of specific body parts physically linked together, the immune system is a diverse collection of cells in the blood and other tissues linked together with ingenious biochemical messengers.
The workhorses of the immune system are cells known as leukocytes or white blood cells. When the immune system is working effectively, the leukocytes identify viruses and bacteria that enter the body and destroy them before they can cause damage and make you sick.
How does exercise affect the immune system?
Moderate exercise – that is most recreational exercise and fitness improvement programs may actually boost immune levels and increase leukocyte activity. So if you exercise say 3 -5 days a week and allow for sufficient rest and recovery between sessions, you will have increased immune levels over your "couch potato" counterparts.
When exercise becomes habitual and training workloads become heavier however, there is an increased risk for what is called exercise induced immunosuppression (EII) or a decrease in immunity levels. Repeated bouts of sickness such as colds and flu may be a symptom of overreaching or overtraining where the volume (amount) and / or intensity of the exercise is too high.
It is thought that intense exercise and high volumes of training that do not allow for enough recovery and rest add cumulative "stress" on the body and the immune system. Just as not getting enough sleep at night negatively affects your immunity, so does excess exercise stress and fatigue.
How can I avoid getting sick if I exercise regularly?
The best way to ensure the integrity of your immune system is to make sure you get enough rest and recover sufficiently from each of your exercise sessions. If you are a competitive athlete or if you are training for an event you may want to ensure that your training program is periodized – that is the exercise intensity and volume are carefully matched to ensure performance success.
Additional ways of ensuring your immune levels stay high is to use the following tips:
1.) Supplement with Glutamine
Glutamine is an amino acid (building blocks of protein) that is known to be a primary energy source for leukocytes. Studies show that blood glutamine levels drop during exercise and during the post exercise recovery process. During exercise glutamine is used as an energy source (leukocytes, kidney cells) and during recovery it is needed to repair damaged tissue and restore blood glucose levels.
By supplementing your diet with additional glutamine right after an exercise session you will help to maintain blood glutamine levels, ensuring muscle and connective tissue repair, adequate recovery and most importantly, immune system integrity.
2.) Supplement with a multi-vitamin
A multi-vitamin that provides 100% of the RDA for antioxidant vitamins such as vitamin A, C and E will also help to maintain your immune levels. Antioxidants neutralize free radicals generated during exercise. Free radicals are products of energy metabolism that tax the immune system and cause oxidation of tissue and conditions such as cancer and heart disease. Oxidative stress is particularly high among athletes and avid exercisers because of the increased use of the aerobic metabolism system.
Multi-vitamin supplementation has been shown to increase the activity of certain leukocytes – especially a certain type called neutrophils.
3.) Make sure you get enough carbohydrates
Ingesting carbohydrate both during and after exercise will also help maintain your immune levels and allows you to recover faster too.
The effect of carbohydrates on immunity is indirect as they have a "protein sparing" effect, which ensures that glutamine levels do not drop, leaving leukocytes starved for energy.
Carbohydrate taken during exercise helps maintain blood glucose levels, reducing the need to use glutamine and other amino acids (from valuable skeletal muscle) to make "new 'glucose in a process called gluconeogenesis. During the recovery process carbohydrates will help to replenish liver and muscle glycogen (stored carbohydrate) without having to rely on your blood glutamine and other amino acid stores for new glucose.
Carbohydrates taken during exercise itself (eg energy drinks) also stimulate saliva flow, which helps flush airborne bacteria and viruses from your mouth and respiratory tract that may enter during exercise and cause infection.
In closing, this article has shown that even though moderate exercise may have an immune system boosting effect, if you are an avid exerciser there may be an increased risk of becoming ill. It is hoped that this article has provided some helpful pointers to help you avoid allowing your exercise to make you sick and allow you to train more effectively not only during winter but all year 'round,