The Truth Is in the Protein Powder

Courtesy of Connor Farrell

As we feasted on turkey this past week, athletes pondered the idea of fuel for their bodies.  The following might surprise you.

Pre-workout supplements are widely used by eager gym-goers and athletes to boost physical ability. With impressive names like NO Xplode, Jack3d and Assault, one calibrated serving can turn you into a psychotic weight lifting machine! At least, that’s the idea.

The secret weapon that these supplements employ is the claim to stimulate nitric oxide (NO) levels in the body. Nitric oxide is a chemical messenger that dilates blood vessels by relaxing their smooth muscle lining. As a result, more blood is able to flow into muscles and power their activity.

This biological scenario is ideal for exercising. Blood is the body’s transport system equipped with many vehicles of nutrients, whereas the blood vessels are the highway. Imagine adding three to four extra lanes to the 405. Although it  might not help LA traffic, it would do wonders for blood flow. This metabolic utopia would function by providing working muscles with more fuel, like glucose, and would eliminate lactic acid buildup from strenuous exercise. The result is better performance during a workout and better recovery afterwards.

But before you set out to raid your local GNC store, ask yourself: Is this too good to be true? Well, let’s take a look at the composition. The ingredients used by these supplements to excite NO levels are simple amino acids like arginine and citrulline. Arginine is the substrate for the enzyme nitric oxide synthase, which catalyzes its conversion into nitric oxide and citrulline in blood vessels. This pathway works, but our bodies are under extremely stringent regulation. They are not impressed with a bit of extra arginine lying around (in the context of nitric oxide stimulation).

Thomas Poulos is a professor of biochemistry here at UCI with a Ph.D in biology. A part of his lengthy research career has been dedicated to dissecting the pathway for nitric oxide synthase inhibition.

“Bottom line is that these supplements probably don’t work outside of the caffeine boost,” Poulos said. “NO is a potent molecule and the body tightly regulates how and where it goes. Hemoglobin binds tightly to excess NO so even if arginine boosts NO levels, the NO very likely gets picked up by hemoglobin. The verdict isn’t fully out on these things but be careful. The sports supplement people are in this game to make money, not get you pumped.”

As Dr. Poulos mentioned, most of the “pump” these supplements provide can be largely attributed to the outrageous caffeine content in each serving. This might be the reason why most supplements do not divulge the caffeine content of their products. They also try to mask caffeine with names like methylxanthine, from which neurostimulants like caffeine are ultimately derived.

Still, some estimates reveal that single servings can contain anywhere from 200-300 milligrams of caffeine. Compare this to a cup of regular coffee, which contains somewhere around 75 milligrams of caffeine. So, each serving is like chugging three to four cups of coffee before a workout, morphing you into a jittery beast! This is also why these supplements might recommend tinkering with the serving size in order to find your personal sweet spot, or more importantly, gauge your sensitivity to the caffeine, since excessive amounts can speed up heart rate and cause anxiety.

Arginine and Citrulline may not have a profound effect on NO levels, but are worthy candidates to supplement a healthy diet. Combined with exercise, there are studies showing that consuming arginine and citrulline can decrease cholesterol levels in mice fed a high cholesterol diet. Other studies show a slowing of the progression of atherosclerosis in rabbits fed a high cholesterol diet as well.  These amino acids are abundant in most nuts like almonds and peanuts, which cost a lot less than pre-workout supplements. The same goes for getting your caffeine the old fashioned way from coffee or tea, rather than a white powdery substance.

If you strip pre-workout supplements of these few key nutrients easily obtained from food, you reduce them to nothing more than a tub of hyperbolic claims with a hefty price tag. Pre-workout supplements cost between $1-2 per serving, considering the top brands and bulk prices.

On the other hand, a $10 tub of Folgers can make 270 cups of coffee for you. Add in the $8 cost for a pound of almonds, which on average contains 400 kernels. Let’s say your new pre-workout regimen is two cups of coffee and 10 almonds. Your cost per serving comes out to 27 cents, factoring in 20 cents for almonds and 7 cents for coffee. So, take the organic route for a change; you might be pleasantly surprised.