A Guest Post from Eric Cressey
Of all the lousy things that can happen, this has to be one of the worst.
Imagine: You’ve just completed the most successful bulking cycle of your life, adding twenty pounds of mass; you’re on top of the world. Now, all you have to do is train properly and eat plentifully in order to solidify your gains.
Your girlfriend is so proud of you for making such great gains and transforming your physique that she can’t keep her hands off you. The day before, she had taken a sip from the water fountain at the gym and accidentally touched her lips to the spout. Ten minutes earlier, that skanky “human sweat gland” guy who spends five hours on the elliptical each day had just made out with that same water fountain. That morning, he had kissed his wife goodbye before leaving for the gym. She teaches a kindergarten class that, incidentally, happens to be riddled with the flu…
So here you are. Home sick from work, pitying yourself as you watch the same episode of Sportscenter eight times in a row. All the while, you’re thinking about how you would much rather be deadlifting like a madman and showing off your gains at the gym!
But you need to focus on the task at hand: beating the flu*. Whether you’re a bodybuilder, powerlifter, or a different athlete, you need to take into account how sickness affects performance and physical appearance, whereas normal folks just worry about “getting rid of their sniffles.”
Proper diet seems like a no-brainer, right? One would think so, but I’m constantly amazed at how people vehemently adhere to this primitive urge that tells them to stuff themselves full of shitty foods just because they feel shitty! I’m talking “comfort” foods: Mom’s cookies, white toast with cinnamon sugar, hot chocolate, a whole gallon of ice cream.
They might make you feel all warm and toasty on the inside, but they’ll quickly make you soft and fluffy on the outside.
So what should you eat and what should you avoid?
Sure, you’re afraid of gaining fat while “on the shelf.” But it’s important to assume the mindset of maintaining your physique while bringing the immune system up to par. If you gain a little fat, don’t sweat it. Remember, it’s a lot easier to shed a little fat than it is to regain a few pounds of lost muscle. In reaching your daily caloric goal, as usual, spread your intake out over six smaller meals. Maintenance caloric intake is highly variable, so rather than multiplying your body weight by a certain number to find your target, base your intake on slightly below (100-150 calories) what you would take in on a normal rest day.
This decrease should account for the extra time spent on the couch or in bed.
You’ll want 1-1.5g/lb lean body mass in order to remain in positive nitrogen balance and stop muscle breakdown in its tracks.
Protein needs increase during times of stress, and sickness is certainly one of those times. In a study of critically ill children in hypermetabolic and catabolic states, researchers found that a higher protein intake was associated with positive nitrogen balance, whereas a low intake (with total calories held constant) led to a continued state of negative nitrogen balance and muscle protein catabolism (2). A big steak probably won’t sound too appealing when you’re sick, though, so low carb protein powders (such as Xtreme Ultra Peptide), cottage cheese, omelettes, and other “easy to get down” protein sources might turn out to be your best friends.
When you’re sick, your body isn’t primed for sucking up simple sugars like it is when you’ve just completed a training session. So, the typical bodybuilding “no-no” foods should be even more off-limits than usual. Your best bet is to focus carb intake early in the day when muscle cells are most receptive to storing glycogen.
Even if that means cutting back on carbohydrates. In the aforementioned study of critically ill children, fat was used preferentially for oxidation. Meanwhile, a high carbohydrate intake was associated with lipogenesis (fat formation) and decreased fat oxidation (2). Thirty percent of your total calories is a good figure to support endogenous testosterone and overall energy levels (since fat is the primary source of energy at rest). Your body will be forming plenty of new immune cells as you fight off sickness, and fatty acids constitute an important component of each new cell membrane. Therefore, in order to give the body the best raw materials available, make sure that you’re getting plenty of Omega-3 fatty acids.
Don’t fall into the trap of overdoing the Omega-3s. While fish oil has proven effective in enhancing immune function in certain clinical situations (e.g. rheumatoid arthritis, ulcerative colitis) and in animals, studies of healthy humans are yet to yield consistently favorable results to substantiate the claim that Omega-3s enhance immunity (4). As such, there does not appear to be any greater benefit (at least not yet) to increasing Omega-3 PUFA intake during times of sickness. Simply stick to your normal intake levels, relying on healthy sources such as fish oil and flaxseed oil for your supplemental fat intake.
You might think that because you aren’t training, you don’t need to worry much about H2O- big mistake. The body loses a significant amount of fluids each day independent of training. We’re constantly losing water through our breath as we dissipate heat through our skin without even knowing it. Factor in increased mucus production, the sweating that may be associated with a fever, the fact that your body is constantly constructing new cells (especially during sickness), not to mention your higher protein intake, and you can begin to realize the importance of really emphasizing water intake. Shoot for at least one gallon (preferably more) of water daily.
All these considerations in mind, I highly recommend you pick up a copy of Precision Nutrition from Dr. John Berardi. His information is fantastic, highly effective, and presented in a user-friendly format.
First and foremost, get a flu shot. The optimal time to do so is mid-September through November, as it takes at least a week for the shot to really kick into protective-mode. If you need proof that the influenza vaccine is worth the fee (if you even have to pay for it), look no further than a study conducted on a Brazilian airline company’s employees. As I’m sure you can imagine, flight attendants and those in related roles are a population segment that is extremely susceptible to the flu due to their interactions with so many customers in confined spaces. Prior to flu season, each of 813 employees received either an influenza vaccination or a placebo. Seven months later, the employees who had received the vaccines showed 39.5% fewer episodes of flu-like illness than the placebo. Additionally, the vaccine group took 26% fewer sick days than the placebo group (5).
From a weight-training standpoint, fewer sick days corresponds to fewer missed training sessions. In addition to the flu shot and your regular multivitamin, you should definitely include the following:
Vitamin C (ascorbic acid) is the first immune-booster that comes to mind. A vital component of every cell in the human body, ascorbic acid is perhaps most notably found in high concentrations in leukocytes (white blood cells). The leukocytes are constantly being produced in the bone marrow as safeguards against bad stuff like cottage cheese gone sour, reruns of those obnoxious Subway commercials with Jared, curling in the squat rack, and, oh yeah, infections.
During infection, in order to prevent oxidative damage, the vitamin C within the leukocytes is used up faster than a post-workout shake (4)! Thus, it should come as no surprise that reduced leukocyte vitamin C levels are associated with less than optimal immune function. (6)
Despite some controversy(7), it appears that supplementation with vitamin C improves several aspects of the human immune response (8, 9), affecting positive changes in proliferation and/or function of in three of the five types of leukocytes: lymphocytes, neutrophils, and monocytes (10-16).
Based on the available literature, I recommend 2-2.5g of supplemental vitamin C daily during normal training conditions and 4-5g daily during flu-like symptoms and times increased of training stress. Doses of up to 10g per day have been used in numerous studies without serious toxicity symptoms, though the side effects of such high consumption may include diarrhea and, in serious cases, kidney stones or urate crystals” (7). Be sure to spread your intake throughout the day in 500mg doses to maximize the absorption(17).
Perhaps as important as vitamin C is Vitamin E, which works synergistically with selenium in tissues to reduce lipid membrane damage during infections (4). Vitamin E has proven effective in improving various parameters of the immune function, including enhanced lymphocyte production, improved antibody response to vaccine, reduced pulmonary viral titers (a measure of virus prevalence in respiratory infections), and “preventing an influenza-mediated decrease in food intake and weight loss” (18-20). No decrease in food intake? Maybe that steak won’t sound so bad after all!
Even the slightest deficiency in vitamin E can easily compromise one’s immune response. The current RDA of 30 IU is barely adequate in preventing deficiency in sedentary individuals, let alone in athletes, the elderly, and the sick and diseased. You might be able to consume a lot of vitamin E from diet alone (3 ounces of almonds or 2 ounces of sunflower seeds should meet the RDA), but in order to receive enough vitamin E to help ward off the flu, you’ll need a lot more. Don’t worry, vitamin E is one of the least toxic vitamins, although one may experience some minor symptoms (nausea, diarrhea, muscle weakness) with very high dosages (7,21). As such, 800-1200 IU per day, throughout the year (regardless of whether you’re sick or healthy) is an optimal approach.
Glutamine is the most abundant amino acid in the human body. Although over 40% of the body’s glutamine is devoted to fueling the GI tract, this amino acid also plays a role in the functioning of many other parts of the body, including the liver, brain, muscles (duh!), hair follicles, kidneys, and – you guessed it – the immune system (7,22-24).Plenty of glutamine is necessary to ensure optimal proliferation and function of lymphocytes, macrophages, and neutrophils (25,26).
Because glutamine is crucial for a variety of metabolic processes, it is only logical that a sick body requires more of it in order to “bolster” the immune system while maintaining normal physiological functioning (24,26).
The body’s response to infection, injury, and stress is muscle breakdown. In order to sustain its metabolic processes, the body takes glutamine from muscle. Normally, this isn’t a big deal because the body makes its own glutamine, but during times of stress or sickness, numerous organs show marked increases in glutamine uptake. When combined with the needs of the immune system, GI tract, and the regular metabolic processes, glutamine gets sapped faster than you can make it, and your beloved quads become fuel for your body’s lunch(23,27).
Obviously, you need to supplement with glutamine. Numerous studies have shown that doing so helps to maintain positive nitrogen balance, improve muscle protein synthesis rates, increase growth hormone, and enhance immune function(7, 28-35). Also, let’s not forget that glutamine’s ability to enhanve your immune system makes it an effective year-round, recovery-promoting supplement for hard training athletes, especially during and shortly after periods of intensive training (7,33,34). During illness, shoot for 0.35-0.4 grams of glutamine per kilogram of body weight, and spread your intake out throughout the day in 3-5g doses. Based on absorbability, I recommend glutamine peptides. L-glutamine (free form), however, tastes better, generally costs less, and will also yield favorable results.
In some rodent studies, thirty days of low zinc intake caused an 80% reduction in immune capacity, so it should come as no surprise that zinc deficiencies are prevalent in among stressful chronic illnesses, including HIV, kidney disease, and alcoholism (4,36).
Studies on the benefits of zinc supplementation in enhancing immune function have yielded mixed, but mostly favorable results. Popping zinc pills upon the onset of a cold or upper respiratory tract infection has been shown in some studies to decrease the sickness’ duration and severity (7,37-39). Meanwhile, zinc supplementation in long distance runners prevented the typical increase in reactive oxidation normally seen with endurance activity (41).
If you take nothing else from all these studies, at least walk away from this article cognizant of how important sufficient intake is, especially for athletes—who are more likely to be deficient than the general population. In terms of preventative supplementation, researchers found that of 609 school children, those who supplemented with zinc had 45% fewer acute lower respiratory infections over the 120-day study (42). While too much supplementation can suppress the immune system, moderate supplementation throughout the year with slightly increased dosages beginning at the onset of flu- or cold-like symptoms is an effective and safe approach (7).
When you’re sick, take at least 25 milligrams of zinc per day, and no more than 100 grams. I like the supplement ZMA, as it will enable you to meet your zinc needs while increasing anabolic hormone levels, improving recovery, and promoting deep, restful sleep.
Although vitamin A is of unquestionable importance to proper immune functioning, there is no real evidence that supplemental vitamin A offers additional benefits over your standard dietary intake. In fact, excessive vitamin A intakes have been associated with suppression of T- and B-cell function, which actually makes you more susceptible to infection. Toxicity can also become an issue with higher intakes, and in any event, vitamin A deficiency is very uncommon in wealthier nations. If you feel that you need to get more vitamin A (preformed vitamin A is called beta-carotene) than your diet alone provides, make sure to select a multivitamin with at least 5000 micrograms (4,7).
Although a few studies show slightly (and relatively insignificantly) shorter respiratory tract infections in patients treated with echinacea, most have demonstrated that the herbal product has little or no effect on preventing and treating sickness. The surrounding science is made murkier by the fact that there are nine species of the plant, different parts (leaves, stem, roots, flowers) of the plant can be used, and different forms are available (e.g. powder, liquid extract, capsule). Essentially, even if echinacea was definitively proven effective, an argument would still exist over which species, form, and delivery produces the best results. At this point, there is not enough evidence to recommend echinacea as a worthy supplement (7,43-45).
There’s some evidence that this nonessential amino acid can improve immune response and wound healing by boosting lymphocyte production in people with compromised health status. However, most studies have shown that arginine supplementation is of no benefit if you’re trying to enhance the immune response, especially in healthy individuals (7). Given that some clinical trials use upwards of 20g L-arginine per day (mostly without appreciable immunity-related results), forty capsules per day seems like far too risky an investment even if you enjoy being a human guinea pig. Even if you do decide to give arginine a try, be careful; excessive intakes can actually blunt the immune response (46).
The old “8-hours at night” recommendation still holds true… as a minimum. You should also be shooting for a nap or two during the day.
It seems like a no-brainer to say that you shouldn’t be training when you’re sick, but I’m constantly amazed at how many people still go the gym in spite of their wheezing, sore throats, and aches. Before you stumble off the couch and over to your local gym, ask yourself if your body could really recover from a heavy training session if it hasn’t even recovered from the flu.
If that doesn’t send you home, maybe it will help to think about how your decision to go train will impact others; you’ll probably make half the people in the gym sick just like the “human sweat gland” did to you. Stay home, if not for your own sake, then for the sake of everyone else who enjoys his or her health and visits to the gym.
Get over the flu and then get back to the gym!
1. The Merck Manual of Diagnosis and Therapy. http://www.merck.com/pubs/mmanual/section13/chapter162/162b.htm; 1995 accessed Sept 2002.
2. Coss-Bu JA et al. Energy metabolism, nitrogen balance, and substrate utilization in critically ill children. Am J Clin Nutr 2001 Nov;74(5):664-9.
3. Calder PC et al. Fatty acids and lymphocyte functions. Br J Nutr 2002 Jan;87 Suppl 1:S31-48.
4. Field C. et al. Nutrients and their role in host resistance to infection. J Leukoc Biol 2002 Jan;71(1):16-32.
5. Mixeu MA et al. Impact of influenza vaccination on civilian aircrew illness and absenteeism. Aviat Space Environ Med 2002 Sep;73(9):876-80
6. Schwager, J. et al. Modulation of interleukin production by ascorbic acid. Vet Immunol Immunopathol. 1998 Jun 30;64(1):45-57.
7. Antonio, J., & Stout, J. Sports Supplements. Lippincott Williams & Wilkins, 2001.
8. Hemila, H. Vitamin C and common cold incidence: a review of studies with subjects under heavy physical stress. Int J Sports Med 1996 Jul;17(5):379-83.
9. Hemila, H. Vitamin C and acute respiratory infections. Int J Tuberc Lung Dis 1999 Sep;3(9):756-61.
10. Kennes, B. et al. Effect of vitamin C supplements on cell-mediated immunity in old people. Gerontology 1983;29(5):305-10.
11. Penn, ND. et al. The effect of dietary supplementation with vitamins A, C and E on cell-mediated immune function in elderly long-stay patients: a randomized controlled trial. Age Ageing 1991 May;20(3):169-74.
12. Shilotri PG, & Bhat KS. Effect of mega doses of vitamin C on bactericidal ativity [sic] of leukocytes. Am J Clin Nutr 1977 Jul;30(7):1077-81
13. de la Fuente, M. et al. Immune function in aged women is improved by ingestion of vitamins C and E. Can J Physiol Pharmacol 1998 Apr;76(4):373-80.
14. Patrone, F. et al. Effects of ascorbic acid on neutrophil function. Studies on normal and chronic granulomatous disease neutrophils. Acta Vitaminol Enzymol 1982;4(1-2):163-8.
15. Prinz, W. The effect of ascorbic acid supplementation on some parameters of the human immunological defense system. Int J Vit Nutr Res 1977; 47:248-57.
16. Woollard, KJ. et al. Effects of oral vitamin C on monocyte: endothelial cell adhesion in healthy subjects. Biochem Biophys Res Commun 2002 Jun 28;294(5):1161-8.
17. Voldani, A. et al. New evidence for antioxidant properties of vitamin C. Cancer Detect Prev. 2000;24(6):508-23.
18. Meydani, SN et al. Vitamin E supplementation enhances cell-mediated immunity in healthy elderly subjects. Am J Clin Nutr. 1990 Sep;52(3):557-63.
19. Meydani, SN et al. Vitamin E supplementation and in vivo immune response in healthy elderly subjects. A randomized controlled trial. JAMA. 1997 May 7; 277(17):1380-6.
20. Han, SN et al. Effect of long-term dietary antioxidant supplementation on influenza virus infection. J Gerontol A Biol Sci Med Sci 2000 Oct;55(10):B496-503.
21. Beharka A. et al. Vitamin E status and immune function. Methods Enzymol 1997;282:247-63
22. Yeh, SL et al. Effects of glutamine-supplemented total parenteral nutrition on cytokine production and T cell population in septic rats. JPEN J Parenter Enteral Nutr. 2001 Sep-Oct;25(5):269-74.
23. van Acker, BA et al. Glutamine: the pivot of our nitrogen economy? JPEN J Parenter Enteral Nutr. 1999 Sep-Oct;23(5 Suppl):S45-8. Review.
24. Newsholme, P. Why is L-glutamine metabolism important to cells of the immune system in health, postinjury, surgery or infection? J Nutr. 2001 Sep;131(9 Suppl):2515S-22S; discussion 2523S-4S. Review.
25. Saito, H. et al. Glutamine as an immunoenhancing nutrient. JPEN J Parenter Enteral Nutr. 1999 Sep-Oct;23(5 Suppl):S59-61. Review.
26. Ziegler, TR. Glutamine supplementation in cancer patients receiving bone marrow transplantation and high dose chemotherapy.
J Nutr. 2001 Sep;131(9 Suppl):2578S-84S; discussion 2590S. Review.
27. Karinch AM. et al. Glutamine metabolism in sepsis and infection. J Nutr 2001 Sep;131(9 Suppl):2535S-8S; discussion 2550S-1S.
28. Wilmore, DW. The effect of glutamine supplementation in patients following elective surgery and accidental injury. J Nutr. 2001 Sep;131(9 Suppl):2543S-9S; discussion 2550S-1S. Review.
29. Boelens PG. et al. Glutamine alimentation in catabolic state. J Nutr. 2001 Sep;131(9 Suppl):2569S-77S; discussion 2590S. Review.
30. Yoshida, S. et al. Effects of glutamine supplements and radiochemotherapy on systemic immune and gut barrier function in patients with advanced esophageal cancer. Ann Surg. 1998 Apr;227(4):485-91.
31. Valencia, E. et al. Impact of oral L-glutamine on glutathione, glutamine, and glutamate blood levels in volunteers. Nutrition. 2002 May;18(5):367-70.
32. Yoshida, S. et al. Glutamine supplementation in cancer patients. Nutrition. 2001 Sep;17(9):766-8.
33. Castell LM., & Newsholme EA. The effects of oral glutamine supplementation on athletes after prolonged, exhaustive exercise. Nutrition 1997 Jul-Aug;13(7-8): 738-42.
34. Rosene, MF. et al. Glutamine supplementation may maintain nitrogen balance in wrestlers during a weight reduction program. Med Sci Sports Exerc 1999;31(5): S123.
35. Welbourne, TC. Increased plasma bicarbonate and growth hormone after an oral glutamine load. Am J Clin Nutr. 1995 May;61(5):1058-61.
36. Fraker, PJ. et al. The dynamic link between the integrity of the immune system and zinc status. J Nutr 2000 May;130(5S Suppl):1399S-406S.
37. Prasad AS. et al. Duration of symptoms and plasma cytokine levels in patients with the common cold treated with zinc acetate. A randomized, double-blind, placebo-controlled trial. Ann Intern Med 2000 Aug 15;133(4):245-52.
38. Al-Nakib, W. et al. Prophylaxis and treatment of rhinovirus colds with zinc gluconate lozenges. J Antimicrob Chemother. 1987 Dec;20(6):893-901.
39. Mossad, SB. et al. Zinc gluconate lozenges for treating the common cold. A randomized, double-blind, placebo-controlled study. Ann Intern Med. 1996 Jul 15;125(2):81-8.
40. Berger MM. et al. Trace element supplementation modulates pulmonary infection rates after major burns: a double-blind, placebo-controlled trial. Am J Clin Nutr. 1998 Aug;68(2):365-71.
41. Singh A. et al. Exercise-induced changes in immune function: effects of zinc supplementation. J Appl Physiol 1994 Jun;76(6):2298-303.
42. Sazawal S. et al. Zinc supplementation reduces the incidence of acute lower respiratory infections in infants and preschool children: a double-blind, controlled trial. Pediatrics. 1998 Jul;102(1 Pt 1):1-5.
43. Gunning, K. Echinacea in the treatment and prevention of upper respiratory tract infections. West J Med. 1999 Sep;171(3):198-200.
44. Brinkeborn RM. et al. Echinaforce and other Echinacea fresh plant preparations in the treatment of the common cold. A randomized, placebo controlled, double-blind clinical trial. Phytomedicine. 1999 Mar;6(1):1-6.
45. Grimm, W, & Muller, HH. A randomized controlled trial of the effect of fluid extract of Echinacea purpurea on the incidence and severity of colds and respiratory infections. Am J Med. 1999 Feb;106(2):138-43.
46. Wiebke EA. et al. Effects of L-arginine supplementation on human lymphocyte proliferation in response to nonspecific and alloantigenic stimulation. J Surg Res 1997 Jun;70(1):89-94.
* Disclaimer: The term “flu,” short for influenza, is really only one of several common kinds of viral respiratory infections, like the common cold, pharyngitis, laryngitis, tracheobronchitis, and viral pneumonia (1). Regardless of the clear differences in the nuts and bolts of each infection, they are generally all lumped together and called the flu by the general public. It’s erroneous, but that said, these tips will apply to the majority of “flus” out there.