How Does Running Impact Your Immune System?
The role of the immune system in our body is quite pivotal, and ever since the COVID-19 pandemic began, this has become a much-discussed topic. The body’s immune system is a network of cells, organs, and proteins that work together to protect it against infections. The two main parts of the immune system are the innate immune system, which is present since birth, and the acquired or adaptive immune system, which develops as a response to an infection or vaccination. These systems work together and take on different tasks to act as the body’s defense system.
We know that regular exercise and a healthy diet are the primary pillars of a strong immune system. So, does running as a workout regimen and a sport boost your immunity? Let’s find out what science says.
How does running benefit the immune system?
A lot of research has been done to understand the short-term and long-term effects of exercise on the immune system. Your body identifies exercises that raise your heart rate for a sustained period, like a 30-minute jog or brisk walk, as a stressor. In response to this stressor, it releases specific types of white blood cells such as neutrophils and lymphocytes. The former cells check for signs of microbial infections and respond to attack of pathogens, and the latter ones defend the body against pathogens and produce substances that help in activating parts of the immune system into your bloodstream. So, the levels of these specialized white blood cells in the blood increases during the workout. However, after the workout the levels of these cells begin to reduce, even going below the resting levels.
Although previously thought to be a period of suppression of the immune system, wherein a person may be more prone to infections, it is now suggested that this decline is caused by a process called immune surveillance. During this time, the body sends these cells to other organs like the skin, lungs, or mucosa to look for any signs of infection.
A study published in the British Journal of Sports Medicine showed that individuals who performed aerobic exercise for five or more days a week had lower instances of upper respiratory tract infections over a period of 12 weeks.
Exercising daily over a period has been shown to influence a healthy and anti-inflammatory environment. Despite the immune system weakening with age, performing activities like running regularly may help in slowing down immunosenescence or age-associated deterioration of the immune system. A study found that subjects who engaged in regular physical activities had reduced immunosenescence compared to sedentary individuals.
Can running have a negative impact on the immune system?
It is rightly said that overdoing any activity can harm you. Despite the plethora of advantages offered by regular exercise, it is possible to overdo it. Overtraining or pushing yourself too hard can prove to be counterproductive and cause problems such as burnout and injuries.
Overtraining Syndrome (OTS) is a condition where vigorous training coupled with insufficient rest and recovery results in performance decline. One of the common signs of OTS is suppressed immune function, which is often characterized by a heightened occurrence of upper respiratory tract infections. An increased risk of upper respiratory tract infections is also linked to high volume or intensity of training and excessive exercise.
Do note that you have to push yourself past your threshold to reach the level of training, which can negatively impact your health and increase your risk for infections. However, it is suggested that the right side of this model may not apply to elite athletes, where higher training loads are not always related to a greater risk of illness.
Although it may not be likely that you cross your physiological threshold for running, possibly, you may run too much too soon without getting enough recovery. Several factors like fitness levels, age, sex, and genetics can influence an individual’s training threshold. So, it may differ from person to person. Here are some signs that can indicate that you may be overdoing your running exercise:
- Persistent fatigue
- Loss of motivation
- Lack of focus
- Recurring injuries
While moderate exercise can cause mild immune-associated changes, it is indicated that intense exercise lasting more than 90 minutes per bout may cause reduced immunosurveillance, which may raise the risk of upper respiratory tract infections.
Additionally, research suggests that factors like poor nutrition, stress, anxiety, and insufficient sleep, which may be present prior to acute bouts of exercise, may contribute to the increased risk of infections instead of just the immune changes that occur during the intense bout of workout.
Tips to maintain your immune health while running
1. According to the American Heart Association (AHA), it is recommended to get at least 150 minutes of moderate to intense physical activity or 75 minutes of vigorous activity or a combination of both, spread through the week. Research suggests that moderate to vigorous intensity that lasts less than 60 minutes per bout improves immune defense activity and overall metabolic health. In contrast, high exercise training load is linked with alteration in immune function, oxidative stress and increased illness risk. However, the risk of illness is also a function of nutritional deficiency, psychological stress, recovery and physical wellbeing.
2. Along with regular physical activity, nutrition plays a key role in your overall health. Make sure that you fuel your runs well. Eat a well-balanced diet to meet your macronutrient requirements and get all the essential vitamins and minerals. For instance, getting adequate Vitamin C can help in protecting you against free radicals that are produced when you go through intense workouts.
3. Research shows that glycogen depletion can stress the immune system. So, it is important to drink a carbohydrate beverage as soon as you finish your workout or at least within 30 minutes of completing the activity.
4. Consumption of water is essential to maintain blood plasma within healthy levels. Ensure that you hydrate well before, during, and after your runs, as dehydration can stress the immune system.
5. Sleeping well every day can help you recover well from your workouts. The general recommendation for adults is to sleep for seven to nine hours.
6. Psychological stress is also known to negatively impact your body. If you find yourself experiencing the common symptoms of stress such as frequent bouts of anxiety, restlessness, and fatigue, identify its cause. Stress can also impact your running performance. Practicing stress management techniques like meditation or gentle massages can help you feel lighter.
The normal guideline for staying healthy if you are a beginner is to run 20–30 minutes about five times a week. Moreover, it is advisable to complement this activity by taking adequate rest and following a proper diet.
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