The studies have shown that daily aerobic activity reduces upper respiratory tract infections by up to 46 per cent, compared with people who exercise very little or not at all.

According to details, the frequent bouts of colds or coughs, along with constant fatigue during the winter months, are widely recognised.

For this reason, many people turn to vitamins, especially Vitamin C, to strengthen immunity, although regular exercise also plays a part in improving immune health.

A Stanford University–affiliated website, Lifestyle Medicine, has published a collection of exercises aimed at strengthening immunity during winter.

The link between exercise and immunity

Research has confirmed a clear link between exercise and the number of white blood cells.

These cells enable the immune system to fight disease, particularly through activities such as cycling, resistance training, and high-intensity exercise.

According to studies, aerobic exercise is the most effective. High-intensity activity causes minor muscle damage, which briefly increases inflammation during the repair process. As a result, levels of white blood cells rise immediately after exercise to support recovery and prepare the body for future physical strain. This repeated stimulation keeps the immune system alert and lowers the risk of infection.

Exercise has also reduced the severity of respiratory infections by 41 per cent, indicating markedly better health among active individuals.

How much exercise is needed

According to the Centers for Disease Control and Prevention (CDC), adults should complete at least 150 minutes of physical activity each week, along with muscle-strengthening exercises on at least two days.

The decision to exercise during illness depends largely on the severity of symptoms and overall health. With mild symptoms, such as a runny nose or sore throat, light activity like walking or gentle yoga may be suitable. With moderate symptoms, such as fever or significant fatigue, it is better to avoid physical activity and prioritise rest so the body can recover properly.