7 Immune Boosting Tips for Athletes: Part 2

lisa-miller-cyclocross immune boosting


As discussed in Part 1, training and racing put unique demands on an athlete’s immune system. Luckily, immune boosting isn’t difficult or time-consuming. In fact, there are some very simple things you can do to keep your immune system in high-performance mode.

In this post, I’ll cover some very strategic actions, such as focusing on gut health. Because, let’s not kid ourselves. While an athlete’s muscles and cardiovascular system may get all the attention, the gut is running the show. In fact, it’s  estimated that 70-80% of our immune system resides in our gastrointestinal tract. So, stop treating it like it’s nothing more than a food processor and give it some TLC! Other tips are much more tactical, both my personal recommendations as well as research Dr. Greger shares in his new book ‘How Not to Die‘.


Immune Boosting Tip #1: Consider a probiotic supplement.

If you’ve ever had an intestinal infection or have ever taken a course of antibiotics, your intestinal ‘good’ bacteria, most likely took a hit, enabling the ‘bad’ bacteria to take over and lowering the strength of your immune system. Research has shown that probiotic supplements may decrease the incidence and duration of colds and may reduce the risk of upper-respiratory-tract infections. Guidelines for selecting a quality probiotic supplement.

Immune Boosting Tip #2: Eat your probiotics.

Research is emphasizing the importance of not just a high number of microbes, but also a wide variety of different strains in your gut. So, don’t just rely on probiotic supplements.Try to make them part of your daily diet —even just a few tablespoons each day. Good sources of dietary probiotics include live-cultured yogurt, kefir (a fermented dairy product, similar to yogurt), kombucha tea (watch the amount of sugar), tempeh (fermented soy product), kimchi, sauerkraut, pickles, pickled fruits and vegetables and fermented condiments.

Immune Boosting Tip #3: Feed your good bacteria with pre-biotic.

Just as you need the right fuel, so does the good bacteria in your gut. This is where prebiotics, non-digestible plant fibers come in. Think of them as the domestiques for the good microbes. Prebiotics not only provide fuel for the probiotics, but also via their fermentation, create a pH-friendly environment for them and support turn-over of cells in the colon. A whole foods diet will provide ample sources of prebiotics. These include foods high in fiber, such as asparagus, bananas, beans, raw dandelion greens, garlic and jicama, raw or cooked onions, oats as well as whole grain wheat and corn products.

Immune Boosting Tip #4: Berry Up!

All berries are rich in antioxidants, which help to reduce inflammation and avoid illness. However, blueberries are on the select team of immune system boosters, increasing levels of white blood cells known as natural killer cells. We have a few billion of these cells circulating in our bloodstream at any given moment, like snipers ready to take out unwelcome invaders. So, more is better.

However, just one prolonged effort of endurance exercise can drop these special forces by half to about one billion. Blueberries can not only prevent, but also reverse this effect. In one study, athletes consumed about a cup and a half of blueberries daily for six weeks to see if the berries could reduce the oxidative stress caused by long-distance running. Not only did the athletes consuming blueberries reduce their oxidative stress, but they actually doubled their killer cell counts, to more than four billion. So, try adding berries into your diet. Throw them in smoothies or eat as a snack. Frozen berries are a great substitute for fresh. But, select wild, organic berries for the most antioxidants and phytonutrients.

Immune Boosting Tip #5: Go Green With Algae During Training.

You can argue that greens in general, as well as other colorful fruits and vegetables contribute to immune health. But, according to Dr. Greger, chlorella, a single-celled, freshwater, green algae, has proven immune health benefits for athletes. According to a 2012 study in Japan, college athletes given 200 mg chlorella during their training camp maintained steady IgA levels during intense exercise. However, those who received no supplements had a significant drop in their IgA levels.

Chlorella is also high in protein, binds and removes toxins, and supports the healing of injuries. Sold as a powder or compressed into tablets, chlorella might be considered an investment due to the high cost of harvesting.

Immune Boosting Tip #6: Go Yellow Post-Race With Nutritional Yeast.

Fibers in brewer’s yeast have also been found to support immune function by maintaining white blood cell levels after exercise. However, if you’ve ever tried it, you likely found it a tad bitter. Luckily, nutritional yeast has the same fibers and same benefits with a much more palatable, cheese-like flavor. In fact, vegans love it for not only its B-12 content, but also use it anywhere a cheese flavor is desired, soups, sauces, popcorn, on vegetables, etc.

A 2013 study found that after two hours of intense cycling, the number of monocytes (an immune system white blood cell) in subjects’ bloodstreams dropped significantly. But cyclists who were given about three-quarters of a teaspoon of nutritional yeast before they exercised ended up with an even higher number of monocytes than before their work out. This theory was later tested at the Carlsbad Marathon in California. Runners who were given about a spoonful of nutritional yeast daily for the four weeks after the race had about half the rates of upper-respiratory infection compared to the runners who consumed a placebo.

Immune Boosting Tip #7: Read the labels on your sports supplements.

Most athletes use some form of sports nutrition supplements in their training and racing routine. But, be sure to read the labels for more than just the macronutrients and key ergogenic ingredients. Stay clear of artificial colors, sweeteners and preservatives. These are the last thing your body needs when being pushed to the limit. Also, use caution with caffeine and sugar levels. A few brands to consider include Klean Athlete and Hammer Nutrition.

And Then There’s The Basics…

Of course, these tips all assume that an athlete is tending to immune support basics. Don’t cheat on your sleep or rest days. Focus on the variety of colors in your diet, not just the macronutrient ratios. Make sure your diet includes foods with immune boosting nutrients, such as vitamin C (red bell peppers, broccoli and citrus), Zinc (oysters, animal protein, mushrooms and pumpkin seeds) and plenty of garlic and spices, such as ginger, oregano and turmeric. And finally get your vitamin D status checked (especially my PNW friends!). Competing with a vitamin D deficiency is like showing up to a race without the right gear. Now, go knock ’em dead!

Are these tips useful? Let me know what you think and leave a comment below. I certainly hope these tips keep you performing your best through the end of your season!
MB Whistler Immune Boosting


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