Inevitably, you’ll hear about people getting sick this time of year in the Crossfit competition season or immediately afterwords. It’d be easy to blame this on winter and being stuck indoors, but realistically I see this happening all across the country, notably in warm places where people aren’t coughing on each other all the time. Our immune system’s major job is to recognize and then neutralize “stuff” that is foreign… so why does it fail us when we need it most? I love Immunology and I’m a pretty big fan of this exercising for time thing, so it seemed like a good post to put together.
So the BIG question is why is does this happen and what can we do about it? To be clear: it’s impossible to avoid ALL the bugs flying around out there… inevitably even the healthiest, best trained, appropriate supplementing person can and will get sick given enough time. What I am suggesting is that we can minimize our chances of getting unnecessarily sick through taking a few really simple steps.
There is a solid amount of evidence that intense training and specifically exhausting competition (such as Crossfit) increases the risk of infection, notably in the upper respiratory tract. Much of this can be due to effects of the body’s response to stress… and let’s be clear, your training is most definitely a stress on the body. Exercise induced stress (which produces cortisol and a bunch of other cytokines) has often been described as a immunosuppressant, but honestly that’s not really accurate. Instead, it’s better to think of it as a modifier of the immune system. Specifically, intense exercise and the stress response skews the immune system away from what we call a Th1 response (which is great for killing viruses and cancer) and more into a Th2 response (which is great for inducing allergies…shit). Intense exercise performed over extended periods also leads to lower levels of antibodies and fewer Natural Killer cells, both of which are again really great for fighting viruses. All of this to say that extended exercise can dampen the type of immunity that helps fight off upper respiratory tract infections.
What to do about it
Well there’s also a good amount of evidence that inadequate carbohydrate consumption and mis-timed intake of protein can impact the immune system of an athlete. Again, it’s not so much the full-blown dampening of the immune system, as much as it is the inappropriate modification of it. MUCH of this correlates with elevated cortisol levels making it hard to determine what is a direct impact of inadequate feeding and what is secondary to having inappropriate, un-attenuated spikes in cortisol from the exercise. What we do know is that most of the immune system functions optimally on glucose. Virus killing T cells divide best on glucose, phagocytes which uses glucose 10X more than glutamine to eat bacteria and viruses… even saliva production is improved with intra workout carbohydrate consumption and saliva contains a bunch of anti-microbial peptides critical for neutralizing potential pathogens. I don’t want to get crazy technical here, but I’ll list a bunch of references at the bottom for people that want to geek out on this stuff.
Whats cool is that we know that a pretty big dose of carbs post workout can help to stop the production of cortisol through spiking in insulin. Spiking insulin??? Isn’t that bad for you? NO! Not in this case. Remember we are talking about athletes here and not a type 2 diabetic. In this case, post workout carbs and insulin really are your friend, so if your carb source claims to NOT spike insulin, maybe it’s not such a great option in this scenario.
How much should you take? Well it depends on the size of the athlete and duration/modality of effort, but I typically recommend anywhere from 30-60 grams post workout. Don’t be afraid of a little intra-workout carb fueling as well… it can help on a number of different fronts.
Timing is really really important
You really do need to get that carb dose down pretty quickly after the workout is over. One study showed that near immediate ingestion of carbohydrates (and protein as well) helped to prevent decreased functionality of specific aspects of the immune system. If that carb dose was delayed just 1 hour, it no longer had the same beneficial effect. SO… get those carbs in QUICK after your workout is over. How quick? Well, don’t go from your final pull up straight to your shaker bottle and then puke it all up… but once you’ve calmed down and are breathing more or less normally, its a good time.
What about protein???
Now we can’t forget about protein in this situation either. Typically for athletes, you’ll see recommendations of the minimum protein required to be about 1.6 grams per KILO of body weight, but I certainly take things a little higher than that with most of my athletes aiming for more like 2-2.2 grams per kg. Immunologically, we know that failure to consume enough protein drastically affects immuno-organ structure and the functionality of T cells, which again are critical in fighting viruses and cancer. In reality, pretty much ALL immune functions including phagocytosis, cytokine production, and antibody production are screwed by not eating enough protein.
How do we exploit this for our athletes? First, we eat enough protein (see above) on a day to day basis. However, we also want to pay attention to our post workout window with protein as well. You might be interested to note that POST race glutamine supplementation (5 grams) was showed to reduce upper respiratory tract infections in marathon runners. There are some conflicting reports but ultimately there’s enough solid evidence for me to use it in my post workout shake as well. I’m typically looking for my athletes to get 20-30 grams of whey protein isolate (range based on body weight) and for there to be a good amount (~5 grams) of either L-glutamine or glutamic acid in that whey protein supplement.
Hopefully the idea that post workout carbs and protein are important isn’t a shocker to you. Now you just know one more really good reason to pay attention to it. No one likes getting sick and having it happen right before or during a major competition can be devastating. If you have questions, shoot me an email!