-Melanie Battaglia, MS, RDN, LDN

As the summer training season begins and training loads increase over the next few weeks and months, it is important to fuel your body to stay healthy.

People tend to get sick when the weather drastically changes. This is because your body is used to functioning at a certain temperature and when the seasons change, your body, including your immune system, is forced to re-adapt. Similarly, when your training load increases or you have an intense workout, you are stressing and suppressing your body’s immune system. The increased intensity triggers stress hormones to be released (cortisol and oxidative stress), which triggers the immune system to be temporarily reduced after a hard workout. Maybe you’ve noticed that after pretty hard workouts you feel like you are getting sick. This stress response after intense workouts is a normal training adaptation and leads to increased aerobic capacity or fitness. To fully benefit from this training adaptation it is important to try to stay as healthy as possible. Use nutrition to your advantage! With your immune system becoming suppressed over the course of your season and combined with Chicago’s fluctuating weather, check out the following tips to incorporate into your training and fueling routine. (And then sign up for our Nutrition for Athletes class starting April 2!)

Endurance Athlete Vitamin C Needs

Certain vitamins and minerals, such as Vitamin C, may alleviate the stress placed on our immune system during intense exercise. Vitamin C is an antioxidant, which means that it protects against that oxidative stress that occurs after hard workouts in endurance and ultraendurance athletes. Regular intake of Vitamin C can help prevent upper respiratory tract infections.

Avoid the use of Vitamin C supplements if possible. All synthetic Vitamin C supplements sold in the US, such as Emergen-C, are not third party tested and they are actually sourced from China. If the product is not third party tested then you have no idea what you are getting. Also, the stress response from training is a normal process that leads to improved fitness. Because Vitamin C acts as an antioxidant and fights off stress in the body, consuming too much could actually interfere and diminish your training adaptation.  We want to ensure antioxidants do not interfere with training adaptations. Thus, if you are supplementing be careful not to overdo it because it is easy to consume more than is needed from supplements. Consuming vitamins from food sources are generally safe.

  • For athletes exercising most days of the week, it is recommended to have 100 mg/day of Vitamin C. This recommendation can be easily met by eating fruits and vegetables.
  • For ultraendurance athletes, you may need 250 – 500 mg/day (from food sources) due to the extra training stress.
  • GREAT sources of Vitamin C: Brussel sprouts (74 mg/cup), broccoli (81 mg/cup), chili and bell peppers (119 mg/cup), kiwi (167 mg/cup), oranges (96 mg/cup), papaya (140 mg/cup), and guava (377 mg/cup).

Probiotics for an Immune Boost

Probiotics can help improve your immune function. Bacteria lives in your mouth, gut, and skin. Probiotics can promote the growth of the good bacteria, while protecting against the hostile bacteria. Probiotics can also improve digestion and absorption of food and nutrients. Different probiotic strains offer different benefits, so include a variety of probiotic foods in your diet.

GREAT sources of probiotics:  yogurt, miso, kefir, sauerkraut, apple cider vinegar, and Kombucha.

If you haven’t tried out Kombucha and Kefir yet, here are a few fun facts: Kombucha is dairy free, can help improve digestion, and stimulates your immune system. Kefir is cultured milk, 99% lactose free, and supports digestion. If you can’t eat yogurt, you can try kefir out instead.

Skipping Meals and Snacks

Your body works really hard to keep you going while you are training and functioning throughout the day. As an athlete, you have increased energy needs. Listen to your hunger cues and your body and know that you need fuel throughout the day. By ignoring your hunger cues and skipping meals, additional stress is put onto your body and metabolism and you may be more prone to getting sick.

If you typically skip a meal during the day, try to at least add in a snack containing carbohydrates and protein to minimize using muscle tissue for energy. The Vitamin C fruits and vegetables are great carbohydrate sources and the probiotic foods, such as yogurt and Kefir are protein sources. Try combining a Vitamin C and probiotic food for an immune boosting snack, such as yogurt with kiwi.