Too Much of a Good Thing?

“Americans are drowning in a sea of very bad nutrition information” – T. Colin Campbell, Cornell University.

Dr. Campbell couldn’t be more accurate in his assessment of the western diet, and athletes are no more immune to commonly held misconceptions about diet and nutrition than the morbidly obese.  There are numerous topics one could take issue with under the umbrella of nutritional habits of endurance athletes, but I would like to focus this discussion on the most sought after macronutrient in the the sports world- PROTEIN.  I readily admit that there are many components of the protein debate that are well beyond the scope of what I am discussing here.  Methods such as protein intake during prolonged endurance efforts, or exact post-training protein requirements are better left to those much more qualified than I.

Often I am asked how much protein one should be getting to adequately support athletic pursuits; from the weekend warrior to the serious runner logging 100 miles a week, and I'm shocked at the wide range of assumptions people hold about the ‘right’ amount of this misunderstood nutrient.  Based on my experience, the most prevalent thoughts on protein in the endurance sports world seem to be:

a)      Protein must be consumed after all workouts

b)      As a general rule, more is better

The best way to combat misinformation, rumors, and ‘hype’ produced by magazines or for-profit supplement companies is with unbiased science.  Here are some known truths about daily protein requirements.  The current Dietary Reference Intake for protein is 0.8/g/kg/day for adults- regardless of physical activity status.  This standard satisfies the protein requirements for 97% of all American adults, but is probably not exceptionally relevant to this audience.  The American Dietetics Association (ADA) recently put forth revised protein requirements for recreational and competitive athletes, (but what might come as a shock to those slurping protein shakes daily) the dietary protein needs of endurance athletes are not all that different than those of society at large, when expressed as a % of total calories consumed.  The ADA Sports Nutrition Manual for Professionals (4^th Ed; 2006) advises the following (male & female):

Individual Demands	g/kg/day	Approx % of Daily Energy
Sedentary	0.8	8%
Endurance	1.2-1.4	9-10%
Strength	1.6-1.7	14-15%

    

Based on the above model, a 154 lb (70 kg) male endurance athlete consuming 3800 calories daily should be striving for 84-98 grams of protein a day.  With a diet rich in whole grains, legumes, fruit, vegetables, and fish or some other animal source, reaching 85-100 grams of protein is a fairly easy task…WITHOUT the aid of protein bars, shakes, excess meat or supplement consumption.  With regard to protein consumption, more is not always better! 

It also concerns me that many athletes think that after any training session/workout, protein is a critical and immediate need.  Yes, after a hard 2.5 hour brick workout or tough 3500 yards in the pool, glycogen replenishment (and a little protein) should certainly be the first thing on your post workout agenda.  Where most go wrong is in thinking that a protein bar is a necessity after a 35 minute recovery run or light strength training session.  If you are taking in small, nutritionally balanced meals frequently throughout the day- hydrate and skip the extra calories, you might be lighter and faster for it on race day!  

The take home message is that protein is not a magical nutrient that unlocks athletic potential. Although protein is a necessary component of the diets of athletes and non-athletes alike,  carbohydrates are substantially more important to athletic function/success for endurance athletes.  The vast majority of endurance athletes eating a well thought out diet of minimally processed foods are more than likely meeting their respective protein requirements without the use of protein supplements.  Lastly (and most importantly), be critical of where you get your nutrition information.  Gravitate towards peer reviewed journals based in science, NOT health or fitness magazines from the local news stand.

Some great nutrition resources:

The China Study, by T. Colin Campbell (2006)

Sports Nutrition; A Practice Manual for Professionals, Marie Dunford (editor) (2006)

In Defense of Food; An Eater’s Manifesto, by Michael Pollan (2008)

Thanks for reading,

jw