While we all talk about boosting our immune system, in reality this complex system is still not completely understood and there is no ‘one’ way. It has many scientists intrigued as they continue to study the impact of diet, exercise, stress and other factors on immune response.
What is your immune system?
Your immune system is made up of innate and adaptive systems. Innate refers to tissues and structures like skin, the lining of our gut and some attacking cells (neutrophils, macrophages and dendritic cells). The adaptive immune system is more sophisticated and refers to specific cells that fight different microbes. The main cells are called; B cells, helper T cells and killer T cells. These systems work together, recognise anything unfamiliar in your body and attempt to destroy it. Your immune system usually does an amazing job of defending your body but at times it does fail, for example the stomach bug that saw me turn into the exorcist recently!
All aspects of our life can impact on the immune system from our age, gender, diet, medication and level of exercise.
How does exercise boost your immune system?
Regular exercise is a part of a healthy lifestyle, which helps lower blood pressure, improve circulation, keeps your bones strong and helps keep your weight under control. You may find it interesting to know that scientists are yet to find a direct link between exercise and a healthier immune system, although generally they understand that regular exercise is an important means for keeping the immune system healthy. Some other theories include:
- Exercise can help flush bacteria out of the lungs and airways;
- Exercise change antibodies and white blood cells – with these circulating faster they will detect illness earlier;
- The rise in body temperature may prevent bacteria from rising;
- Exercise can slow down stress related hormones;
One of Dr David Nieman’s (exercise immunologist) studies showed that people who walked at 70-75% of their VO2 max for 40-mins per day reported half as many sick days compared to those who didn’t exercise.
When can exercise compromise your immune system?
So here is the interesting part that is still being researched. While exercise is great for you, you should not exercise more intensely just to increase your immunity. Similarly, if you do not recover or rest your body properly you risk weakening your immune system and opening yourself up to infection.
One of Dr Nieman’s other studies found 90-mins or more of high-intensity exercise (endurance races) makes a person ‘more susceptible to illness for up to 72 hours after working out’. He says that during exercise ‘cortisol and adrenaline that raise blood pressure and elevate cholesterol levels temporarily weaken the immune system’. In addition, heavy, long term exercise increases the presence of stress related hormones.
Now this is certainly not an excuse to drop your moderate- intense physical activity or running training because we all understand to improve our fitness we need to continue overload techniques. It just means you should think about this:
- Knowing when enough is enough – don’t overtrain
- Is this type of exercise going to help me achieve my goal?
- Recovery (for a few days) after illness and in particular respiratory infections. Above the head (runny nose) is ok to train but below the head – take some time out
- Get adequate sleep
- Don’t underestimate the stress you are putting your body under – eat well
Don’t restrict yourself just to the gym with weights or running, try these effective activities to maintain a healthy lifestyle:
- Bike riding
- Going to the gym alternate days – including classes
- Golf, dancing
- At least 30min of power walking each day
- Recreational sports – rock climbing
Post workout tips after your moderate-intense workout:
After a workout our immune systems can crash. Try a few of these post workout ideas to boost your recovery:
- Ensure you have around 20g of protein within 60mins of your workout
- Enjoy a fresh juice that includes a mix of vitamins including Vitamin C (citrus fruits or bright coloured fruits – spinach)
- Wash your hands after using equipment
- Don’t wait until you are cold, put on your jumper while you are still warm