You’ve probably heard that exercise strengthens your immune system. A piece of advice we hear today is, “Exercise regularly to keep the common cold at bay.”
But how valid is the idea? Can a morning run or an evening weights session at the local gym prevent us from getting sick? If so, what makes physical activity so beneficial for our immune system?
Exercise And Immune System Health: Is There a Link?
Exercise is a stressor to the body, and doing too much can lead to adverse effects, such as:
- Trouble sleeping
- Body aches
Overtraining can also impair our immune system, increasing the risk of infections, colds, and similar (1).
But, doing the right amount and intensity of exercise can positively impact the body’s natural defense mechanisms (2). Researchers have long known that physical activity strengthens the immune system, as active people are less likely to suffer from chronic disease, the common cold, and other health issues (2).
But what makes exercise so beneficial for us? Let’s look at some mechanisms.
What Makes Physical Activity So Beneficial For Our Immune System Health?
1. Improved Immune Response (And Defense)
The first way in which exercise benefits our immune system is direct. Physical activity appears to boost white blood cell production, which supplies the body with more soldiers to protect it from external invaders (3).
2. Improved Immune System Surveillance
Our immune system consists of various cells with unique roles. Most cells do one thing: eradicate external invaders and keep us safe. But some cells focus on surveillance and circulate the body countless times, looking for invaders. Once they find invaders, such cells eradicate the danger or release chemical alarm signals to let other immune system cells know about the threat.
Research suggests that exercise can enhance the function of such surveillance cells, allowing our immune system to spot invaders more quickly and eradicate them on the spot (2).
3. Upregulated Lymph Circulation
The lymphatic system is part of our immunity and plays the role of circulating lymph (a colorless and watery fluid) around the body. Though less known than other systems in the body, the lymphatic network works alongside our immune system to eradicate external invaders or signal the body of potential dangers, stimulating a systemic defense response.
Exercise is beneficial because it stimulates lymph circulation, allowing the lymphatic system to detect and eradicate threats more effectively (4). Some experts speculate that exercise can reduce the risk of some cancers through the same mechanism.
4. It Helps Us Eradicate Harmful Microorganisms
The fourth way exercise helps the immune system is by decreasing the amount of work it has to do. But what does that mean?
First, our breathing accelerates as we exercise, allowing us to flush out bacteria from our lungs and airways. As a result, exercise can reduce the risk of developing a cold or getting sick from the flu.
Second, exercise leads to a temporary increase in core body temperature, supporting our immunity by preventing bacteria from growing.