Updated: Oct 2
Living a healthy lifestyle includes eating a varied and balanced diet, being mentally active and performing weekly physical activity or exercise to avoid getting sick or physically injured. So what is the effect of exercise on the immune system? And which one is better at boosting immunity? Yoga, Cardio training or weight training?
The goal of the immune system is to defend the body against invaders, like bacteria or viruses. The key players of the immune system are the white blood cells (WBC) which are produced in the bone marrow and some other organs. They are found in the blood and will move through the body in search of invaders. Once they find an invader, they launch an attack and trigger an immune response to protect the body from invaders.
The effect of exercise on the immune system was first published in 1903 and looked at the change in WBC in marathon runners. In this study, the immune system of marathon runners was weaker than expected because running marathons exerts the runners beyond physiological limits and weakens the immune system.
Exercise can have either a positive or a detrimental effect on the immune system, depending on the exercise intensity and duration. This is in line with Traditional Chinese Medicine (TCM) which states that when the Yin and Yang are in harmony, the body is healthy. Any excess or deficiency will cause disharmony and therefore a state of illness. If you exercise too much, there is a deficiency in the Yang energy of the kidney, causing imbalance, which then affects the immune system. For example, if exercise intensity is too extreme (excess), the immune system might weaken for a little while. On the other hand, the body will experience a boost in the immune system after a moderate to vigorous exercise session. This increased immune response will be temporary. However, with regular exercise, a state of harmony and balance can be found and the changes can be long lasting.
Benefits of exercise, particularly cardiovascular training:
increases blood flow to the muscles
improves metabolism and the activity of the immune system
reduce the frequency of getting a cold or the flu by flushing viruses out of the lungs
decrease the level of stress hormones in the short term
Over time, consistent exercise will lower inflammation in the body and increase the ability of immune cells to detect invaders.
Benefits of yoga, or stretching/meditation based exercise like Tai Chi or Pilates
reduces physiological stress and improves the immune response, similar to cardiovascular training, provided that the exercise intensity is at least moderate
reduces psychological stress by decreasing stress hormone levels and therefore boosts the immune system.
The benefits of exercise are well known in TCM with a major difference: in TCM, illness results from an imbalance between the Yin and Yang energy, a disharmony of Qi (vital energy) and more specifically Wei Qi (protective energy or the first line of defense against illness). The lung is in charge of controlling Wei Qi, which helps explain why exercising regularly will lower the frequency of upper respiratory tract infections (cold and flu as mentioned above).
In short, exercise is part of healthy living and exercising regularly will help fight diseases better than with a sedentary lifestyle. The type of exercise (cardio vs strength training vs yoga or weight training) isn’t as important as exercise intensity and duration. This has great implications in chronic diseases such as cancer, diabetes and heart disease: science is now telling us that exercising regularly can protect us from developing chronic diseases.
Registered massage therapist, Certified personal trainer, Student acupuncturist
Founder @ Dur1 Health
Loise Perruchoud, PHd, Student of health and fitness