Exercise as medicine – Can it improve Immunity?

By Bhagwathi Nambirajan,

The immune system is a large and complex system with a wide range of functions. One of the main functions of the immune system is to protect the body against any foreign organisms and infections, thereby keeping the body healthy. Several factors such as age, gender, presence of a pre-existing medical condition, eating habits etc can have an influence on the functioning of your immune system. Being physically active and fit plays a very important role and has shown to have plenty of health benefits such as prevention of metabolic problems, systemic inflammation and non-communicable diseases such as diabetes, cardiac diseases etc. Similarly, exercises have demonstrated potential benefits in improving immunity and preventing communicable diseases as well. Regular physical activity and exercise promotes cellular immunity and therefore the immune system is very responsive to exercise. How well the immune system is modulated, depends upon certain factors such as how regularly one exercises, at what intensity, duration and type of effort applied during an exercise session.

An acute bout of moderate intensity exercise stimulates cellular immunity, where activation of the muscle fibers and improved blood circulation during exercise is responsible for enhancing the concentration of lymphocytes and the white blood cells. It also improves the anti-pathogenic activity of tissue macrophages. Therefore, exercise is considered as an important adjuvant to stimulate the immune system. At the same time, if one performs the right intensity of exercise for a longer duration of time, the same effects can be observed in an enhanced manner, which brings about an enhanced immune defense activity and metabolic health which in turn further improves immunity.

The intensity at which we perform physical activity or exercise is integral to good health. While moderate amounts of exercise may enhance the immune function above that of sedentary levels, high intensity exercise loads cause an immune dysfunction. Hence, physical exercise when performed at very high intensities especially for long durations usually reduces the ability to defend the body against infections for hours, which can extend up to a day too. The chronic effects of very high intensity exercise therefore are higher susceptibility to infections due to the reduced functioning of the immune system. This negative effect of high intensity training can be offset with appropriate rest intervals.

To be able to get into an effective regime of daily exercise, let’s have a look at the practical applications for exercise prescription. In the light of available data, exercise regime to improve immunity can be prescribed in the following manner. Keeping your baseline fitness levels and existing medical condition in mind, one can opt for a low to moderate intensity work out session with the intensity ranging between 40%- 60% of VO2 Max, 3 to 5 days a week. Usually, duration of a workout session can range from 20 minutes to 60 minutes/day where the international guidelines recommend avoiding continuous exercise beyond 60 minutes per session. One can choose from a range of exercises which includes a component of aerobic exercise and strength training as well. Ensure that the exercise regime that you choose is something that you enjoy, add variability and progress at regular intervals. This will ensure long term sustainability and effective participation, thereby bringing about enhanced long term immune boosting effects. The above recommended exercise prescription is usually effective and safe for participation. However, we recommend that the individual undergoes a baseline cardiac screening and physical fitness assessment before choosing to adopt an exercise regime in their daily practice.

Therefore, regular exercise at moderate intensities along with a balanced lifestyle, nutrition and mind can help stimulate the immune system and improve the body’s immune defense mechanisms, therefore protecting the body from common colds, flus, respiratory infections and various other bacterial infections.

(The author is Cardio-respiratory Physiotherapist; Director – Prophysio Healthcare Pvt. Ltd. The article is for informational purposes only. Please consult medical experts and health professionals before starting any therapy, medication and/or remedy. Views expressed are personal and do not reflect the official position or policy of the Financial Express Online.)