As I sit here pondering the recently concluded Staley Training Summit, I'm left wondering - as I often do - how far overboard I went with my whirlwind lecture on diet and recovery.
So, in an effort to expand Chris Shugart's write up of the Summit, I've decided to expand on a few of my protein topics for those who couldn't attend.
To be honest, I've avoided writing and talking on protein for a long time due to its beat-to-death nature. And I mean beat... to... death. But several months ago, after hearing a protein-bashing nutritionist go overboard about the dangers and over-consumption of the stuff, I decided to start exploring the literature for reasons protein can be advantageous to athletes.
As I read, I became increasingly curious regarding nutrition support beyond mere building blocks. What I found may surprise you, and I believe this mini-review will help bring protein back to its rightful place as valuable training support. (If you already revere the nearly pharmaceutical nature of the nitrogenous stuff, read on; you may still pick up a tip or two!)
Negative Energy Balance
Are free-living athletes like the well-fed, closely monitored research subjects upon whom we base our protein conclusions?
I'd like to offer a few issues in which I think athletes differ. These issues surround energy balance--a known massive affecter of protein needs. Indeed, it has been demonstrated that as one adds more and more kcal, he sees better and better nitrogen retention.(5)
But can athletes even achieve surplus, quality calorie intake? It's tougher than you might think. Many athletes just plain under-eat.(9,10) Staley himself once related how tough it was to consume 30g of fiber per day and still get enough calories to grow. But that's truly just the beginning.
When we figure that an average college male requires about 3000kcal per day just to maintain his body weight,(2) imagine what two-a-day practices with the team can lead to. Then add-in his work under the iron. Then add in his additional muscle mass, which causes his body to rifle through calories - even at rest - like an idling 1970s muscle car rifles through gasoline.
Now, admittedly, the higher calorie needs of additional muscle mass may have been overestimated in the past compared to more recent estimates (18), but you can see that a hard-training athlete's kcal requirements add up fast.
Then let's throw-in injuries, which 90% of the Training Summit attendees indicated they had to endure. The crowd's assertion that a little "hurt" is all-too-common has indeed been confirmed by research reports.
Two studies come to mind in which 50-67% of athletes from the recreational level to the national level put up with injuries.(8, 26) And most of these by far are the type that doesn't completely shut the athlete down; rather, they continue to practice and train whilst enduring the additional nutritional demands.(22)
Injury, whether it's skeletal trauma or soft tissue damage or even delayed-onset muscle soreness (DOMS from using "negatives" in the gym), is widely known to contribute further to calorie needs. This has to do with the body's hyper-metabolic stress response, or acute phase response. As time passes it also involves the expensive need to rebuild new and repaired tissues.
Lastly, we might include overtraining (call it overreaching if you like). It's worthy of another article entirely but we can summarize the highlights (or low-lights, as it were). A combination of staleness, cytokine increases, cortisol elevation, adrenaline elevation, and poor sleep don't bode well for an athlete.
These changes can further hike up calorie needs whilst further interfering with glucose tolerance. Ugh. When added to the other factors that place calorie demands on athletes, we approach an almost impossibly high need. Or said differently, we are forced to deal with negative energy balance--a state similar to that of a dieter.
Proteins and Amino Acids to the Rescue?
Enter protein. When we consider that a 3500 or even 4000 kcal intake can become necessary for a free-living (i.e. "real world") athlete to make new gains, we're going to have to at least consider alternatives to simply pumping him full of carbs.
This becomes especially true when we consider that sore (eccentrically "damaged") athletes' muscles become resistant to carbohydrate.(7, 29) It's truer still when we observe that sleep debt, which so many of us deal with, harms our ability to metabolize carbs as well. Although protein is certainly not a preferred fuel source by the body, it can be deaminated and used as a "fuel" (containing 4kcal per gram, of course) and its presence can bring those in negative calorie balance back toward normal.(3)
This is done in part by the ability of the amino acid leucine to be oxidized in skeletal muscle. Perhaps better still, leucine appear to "turn on" (or at least "turn-up") aspects of the insulin signaling pathway.(15) It has, in fact, long been known to stimulate protein synthesis in skeletal muscle. That sounds drug-like, to be sure.
We can even see this effect in fairly recent human research where spiking a protein and carb shake with additional leucine has superior anabolic effects.(12) It truly is a unique amino acid in many ways.
And however often David "Candy" Barr* rips on it, glutamine continues to find research support. I'm not talking about acute performance boosting or massive gains over a month, which is unlikely with any amino acid; I'm talking about nutrition support for beaten-down athletes over time. There's even a glutamine renaissance of sorts among researchers lately. So as not to beat a dead horse, here's a bulleted list of interesting points:
• Glutamine (Gln) increases nasal immunoglobulin-A (a cold-fighting antibody) and may reduce upper respiratory infections (4, 13)
• Gln and whey protein isolates jack-up antioxidant defenses by way of blood and muscle glutathione levels (20, 23)
• Gln aids the kidneys to excrete acid, consistent with its GH-stimulating effects. (28)
• Gln markedly enhances white blood cell function and survival in rats (14)
• Gln may help replenish glycogen stores (27)
• Gln turns on genes that lead to the manufacture of collagen (sounds good for wound healing) according to a researcher by the name of Bellon (1995). And there are others describing this potential benefit.(11)
Am I saying we should supplement leucine and glutamine individually? Not necessarily. Do I supplement with them? Nope, neither one.
I'm not in the midst of brutal training right now. But I have taken about 5g of Gln per day, prior to exercise, in the late stages of dieting with concomitant hard training. I'm ectomorphic by nature and tend to fall apart under the stress of 20 weeks of two-a-day training.
And I might very well pick up some leucine to enhance the effectiveness of my peri-workout shakes. About 3-5 grams per shake should do the trick. But again, I don't add these extra measures during down-times and I don't think the results would be noticeable if I did.
Ample, not Asinine
So how much protein do we need to offset the almost abusive training regimes of many athletes? That's a good question and my reply may perplex you. I'd wager that the old adage of "a gram per pound of body weight" is enough. It does indeed provide a surplus.
Stable isotope studies don't lie and they suggest up to 1.7g per kg. That's less than the gram-per-pound (2.2g per kg) I'm suggesting. And that surplus helps account for the inevitable periods of negative energy balance. Even the "calorie queen" of the research community, who long-deemphasized protein, once wrote that: "when energy balance is negative, an intake of protein as high as 2 g X kg body weight-1 X d-1 may be inadequate to maintain N equilibrium."(3)
So, if a gram per pound is moderately excessive - but in a sane way - why eat more? Overzealous athletes who eat 300g of protein per day don't typically walk around looking like Dave Palumbo, do they? Let me show you two examples of urinary nitrogen measures that I once observed. On the graph, the green line is a guy who consumed five packages of protein per day in addition to a little food (mostly more protein), while the red line is me, who was consuming almost as much protein but eating far more calories.
Who's wasting more dietary protein (via nitrogen losses)? Uh-huh. And we won't even discuss who was far larger and more muscular. (Ahem.) Of course, this isn't a perfect comparison by any means (you can probably think of several control issues), but it does serve the purpose of illustrating how adequate kcal intake enhances protein efficiency. I've seen it inside and outside of the lab.
And since thoughts about Staley's boot camp got me going on all of this, I'll relate a relevant story from that trip. In the Phoenix airport on the way home, I spoke to another hyper-protein zealot. After 300+g daily for three years, he felt rather stalemated as far as gains. He looked fit but was not big, per se.
After a brief chat, it became clear that total kcal intake was his problem. Although he was a bright guy, he was either A.) Entrenched in long-term habits or B.) Unaware that protein alone is not enough. We need more than just "bricks" (amino acid building blocks), we also need "gas for the brick layer's equipment" (calories from carbs and healthy fats).
If we hearken back to our glutamine highlights, we can see that glutamine is a good thing metabolically. Yet researchers have shown that if a person eats a high-protein diet at the expense of carbohydrates, his muscle and (circulating) glutamine concentrations actually fall.(10) Yep, fall - despite the ample protein and glutamine intake. So you see, there are good reasons why we need carbs--and fats--along with our beloved protein.
The Take Home Message
So, as free-living (beaten down) athletes, we probably need protein more than many nutritionists think... as the recent revival of amino acid research suggests. But should we be consuming 300+ grams per day while eating next to zero carbs and/ or fats? Definitely not.
Protein timing is a smarter and less wasteful approach.
Let's look at total daily intakes, I'm a fan of a "standard" diet of 3000kcal (as far as doing comparative research), comprised of 25% PRO, 50% CHO, 25% FAT. That computes to about 185g protein, 375g carbs, and 85g fat. Unfortunately for those wanting a simple life, this profile changes based upon training mesocycles. Hence, the typical request of "gimme your macronutrient recommendation" is too simplistic. So, here are some key points:
1. Just starting a new lifting regime? Always sore? Cut back on "standard" carbs 10%. Replace the kcal with a mix of protein and monounsaturated fat. (omega-3 fats are not consumable in amounts that really impact kcal intake)
2. Are you starting a "diet" phase by cutting back 300-500kcal (of mostly carbs) per day? Add 10% to your protein intake. (2500 kcal x 35% PRO = 215g PRO)
3. Enduring the late phases of a "diet" while still training? Try supplementing 5g Gln prior to cardio and lifting. (Beware, you gluten allergics.) Assess efficacy after 3 months.
4. Are you about to try a bulking phase (wanting to add mass) or a dieting phase (wanting to preserve lean tissue)? Try spiking pre/mid/post workout shakes with say, 3-5g leucine. For dieters, supplementing on alternate days with number 3 above (Gln) would be a decent approach.
5. Lifting with fairly recent injuries? Add 10% to overall kcal intake in the form of protein and monounsaturated fats. Consider also supplementing 5g Gln 1-3 times daily for potential collagen repair.
6. Feeling overtrained with sleep disturbances? Try a evening scoop of protein containing alpha-lactalbumin.(16)
There are cool things to consider regarding protein and select amino acids that go beyond mere "building blocks" for bodily tissues. I know it, Charles Staley's group knows it and now you know it, too.
And I'm personally not too concerned about experimentation here because of the safety profile these nutrients exhibit--including glutamine.(24) I was tempted to go off (with references) on the lack of research support for protein as anything "risky"... but I'd be preaching to the choir.
So, here's to thinking outside the box. I toast you with a P+C shake. Cheers!
NB: A much deeper investigation of protein needs in free-living athletes (including more specific numbers) has been accepted for publication in the scholarly journal, JISSN. Check it out soon at www.sportsnutritionsociety.org.
References and Further Reading:
1. Antonio, J., et al. The effects of high-dose glutamine ingestion on weightlifting performance. J Strength Cond Res 2002 Feb;16(1):157-60.
2. Borel, M., et al. Estimation of energy expenditure and maintenance energy requirements of college-age men and women. Am J Clin Nutr. 1984 Dec;40(6):1264-72.
3. Butterfield, G. Whole-body protein utilization in humans. Med Sci Sports Exerc. 1987 Oct;19(5 Suppl):S157-65.
4. Castell, L., Poortmans, J., and Newsholme, E. Does glutamine have a role in reducing infections in athletes? Eur J Appl Physiol Occup Physiol. 1996;73(5):488-90.
5. Chiang, A. and Huang, P. Excess energy and nitrogen balance at protein intakes above the requirement level in young men. Am J Clin Nutr 1988; 48(4): 1015-1022.
6. Curi, R., et al. Glutamine-dependent changes in gene expression and protein activity. Cell Biochem Funct. 2005; 23(2):77-84
7. DelAguila, L., et al. Muscle damage impairs insulin stimulation of IRS-1, PI 3-kinase, and Akt-kinase in human skeletal muscle. Am J Physiol Endocrinol Metab. 2000 Jul;279(1):E206-12.
8. Galambos, S., Terry, P., Moyle, G., and Locke, S. Psychological predictors of injury among elite athletes. Br J Sports Med 2005; 39:351-354.
9. Gleeson, M., & Bishop, N. Special feature for the Olympics: effects of exercise on the immune system: modification of immune responses to exercise by carbohydrate, glutamine and anti-oxidant supplements. Immunol Cell Biol. 2000 Oct;78(5):554-61
10. Gleeson, M. and Nicolette, B. Modification of immune responses to exercise by carbohydrate, glutamine and anti-oxidant supplements. Immunology and Cell Biology 2000; 78: 554-561.
11. Karna, E., Miltyk, W., Wolczynski, S., and Palka, J. The potential mechanism for glutamine-induced collagen biosynthesis in cultured human skin fibroblasts. Comp Biochem Physiol B Biochem Mol Biol. 2001; 130(1):23-32
12. Koopman, R., et al. Combined ingestion of protein and free leucine with carbohydrate increases postexercise muscle protein synthesis in vivo in male subjects. Am J Physiol Endocrinol Metab. 2005; 288(4):E645-53.
13. Krieger JW, Crowe M, Blank SE. Chronic glutamine supplementation increases nasal but not salivary IgA during 9 days of interval training. J Appl Physiol. 2004 Aug;97(2):585-91.
14. Lagranha, C., et al. The effect of glutamine supplementation on the function of neutrophils from exercised rats. Cell Biochem Funct. 2005; 23(2):101-7.
15. Layman, D. Role of leucine in protein metabolism during exercise and recovery. Can J Appl Physiol. 2002; 27(6):646-63.
16. Markus, C., et al. Evening intake of alpha-lactalbumin increases plasma tryptophan availability and improves morning alertness and brain measures of attention. Am J Clin Nutr. 2005 May;81(5):1026-33.
17. Markus, C., et al. The bovine protein alpha-lactalbumin increases the plasma ratio of tryptophan to the other large neutral amino acids, and in vulnerable subjects raises brain serotonin activity, reduces cortisol concentration, and improves mood under stress. Am J Clin Nutr. 2000 Jun;71(6):1536-44.
18. McClave, S. and Snider, H. Dissecting the energy needs of the body. Curr Opin Clin Nutr Metab Care 2001; 4(2): 143-147.
19. Melby, C., Scholl, C., Edwards, G. and Bullough, R. Effect of acute resistance exercise on post-exercise energy expenditure and resting metabolic rate. J Appl Physiol 1993; 75(4): 1847-1853.
20. Middleton, N., Jelen, P., and Bell, G. Whole blood and mononuclear cell glutathione response to dietary whey protein supplementation in sedentary and trained male human subjects. Int J Food Sci Nutr. 2004; 55(2):131-41.
21. Phillips, S., et al. Dietary protein to support anabolism with resistance exercise in young men. J Am Coll Nutr. 2005 Apr;24(2):134S-139S.
22. Powell, J. and Dompier, T. Analysis of injury rates and treatment patterns for time-loss and non-time-loss injuries among collegiate student athletes. Journal of Athletic Training 2004; 39(1): 56-70.
23. Rutten, E., Engelen, M., Schols, A., and Deutz, N. Skeletal muscle glutamate metabolism in health and disease: state of the art. Curr Opin Clin Nutr Metab Care. 2005; 8(1):41-51.
24. Salehian, B. and Kejriwal, K. Glucocorticoid-induced muscle atrophy: mechanisms and therapeutic strategies. Endocr Pract. 1999; 5(5):277-81.
25. Spiegel, K. Impact of sleep debt on metabolic and endocrine function. Lancet. 1999 Oct 23;354(9188):1435-9.
26. Stevenson, M., et al. Sport, age and sex specific incidence of sports injuries in Western Australia. Br J Sports Med. 2000; 34(3):188-194.
27. Varnier, M., Leese, G., Thompson, J., and Rennie, J. Stimulatory effect of glutamine on glycogen accumulation in human skeletal muscle. Am J Physiol 1995; 269(2 Pt 1):E309-15.
28. Welbourne T, Claville W, Langford M. An oral glutamine load enhances renal acid secretion and function. Am J Clin Nutr 1998; 67(4):660-3.
29. Widrick, J. et al. Time course of glycogen accumulation after eccentric exercise. J Appl Physiol. 1992 May;72(5):1999-200.