Optimized Human Performance

Overcoming three hidden performance barriers
By Ben Greenfield and Joe Stout, MS

Let’s say you have a physical performance goal like running a 5K. Or maybe it’s a bigger goal like a half or full marathon. A bicycling century. An Ironman triathlon. A big tennis tournament. A weight training competition. The Crossfit Games. Shedding 30 pounds of fat and “getting ripped.”

So you work hard—really hard. Every day you hit the gym, you sweat, you grit your teeth and make your muscles burn.

Then one day you realize things aren’t happening the way you imagined. Perhaps you plateau. Perhaps you begin to feel your energy drained every day, and taking a nap sounds far more attractive than exercising. Perhaps you get brain fog, excessive muscle soreness, sore joints, or a loss of libido. Before you know it the enjoyment and satisfaction you thought you’d derive from achieving your amazing feat of physical performance is gone, replaced by a feeling of staleness and chronic fatigue.

Unfortunately this is an all-too-common tale, and often the fix goes far beyond simply taking a rest day, eating a few extra calories, or getting a massage.

There are three major hidden barriers that frequently hold athletes and exercise enthusiasts back from achieving their goals or getting to peak performance levels during games, races, and workouts. We’re going to lay out what these barriers are, and one compound you should include in your diet immediately if you’re serious about overcoming these barriers as fast as possible.

Barrier #1: Food Intolerances

The term “food intolerance” is widely used for a variety of unpleasant responses to specific foods or compounds in foods. (A food intolerance is not to be confused with a food allergy, which is often a dangerous immune response that results in reactions such as seizures or anaphylactic shock.)

A food intolerance typically results from one or more of the following six factors. A lack of enzymes necessary to digest a food (e.g. lactose intolerance); malabsorption, the inability of the digestive system to absorb specific nutrients; a sensitivity (a hyper reaction to some type of pharmacological compound like a food additive, preservative, or coloring); an immune antibody response to food mediated by less serious antibodies than a full-blown food allergy (e.g. gluten intolerance); a toxin present in food from either contamination or mold; or lastly a psychological reaction to food triggered by an emotion associated with that food.

One of the most common food intolerances among athletes and exercisers is lactose. This is a real pity, since dairy foods like yogurt, milk, whey protein, and cheese are chock full of proteins and insulin-like growth factors that can rapidly repair broken down muscles and bodies. But these same foods can severely disrupt athletic performance due to gut distress or a person’s inability to handle the lactose and other proteins in commercial dairy from cattle.

Unbeknownst to most coaches and athletes, however, over 65 percent of the world’s population drinks goat’s milk, and with good reason. This is a concept I (Ben) first introduced to my listeners in a podcast titled “Goat’s Milk versus Cow’s Milk.” Protein and recovery sources derived from goat’s milk are incredibly similar to human milk in composition and are easily digestible—even during or after tough workouts and races. The composition and size of the fat globules in goat’s milk are five to 10 times smaller than those found in cow’s milk. Because of this, the human body can digest goat’s milk in as few as 20 minutes, versus a lengthy two to three hours to digest cow’s milk.

Researchers from the University of Granada have discovered that one reason goat’s milk is so easily handled by the human body is due to its hypoallergenic properties. Their research shows that, like human milk, goat’s milk contains less lactose and also less alpha-s1 casein (a protein commonly associated with a heightened immune system response to dairy). In addition, Norwegian researchers have discovered that when exposed to the human digestive enzymes found in stomach and intestinal juices, the beta-lactoglobulin in goat’s milk is digested three times faster than the beta-lactoglobulin in cow’s milk (similar to casein, beta-lactoglobulin is a milk protein that can cause an allergic reaction).

Upon replacing dairy sources from cattle with dairy sources from goats, many of the athletes I coach and advise have solved everything from brain fog to joint pain. They notice an enormous difference in workout quality and recovery speed in as few as 24 hours.

Barrier #2: Constipation, Bloating, and Gas

Another issue that athletes and exercisers face is the embarrassing digestive milieu that can result from fueling the body with the thousands of calories necessary to sustain high levels of physical activity. Although switching to a form of lactose and protein that is more easily digested can lower food intolerances and eliminate many of these issues, there is another advantage of goat’s milk or recovery protein powders derived from goat’s milk—oligosaccharides.

Oligosaccharides are short-chain sugar molecules that act as a prebiotic in the intestine. This means they help feed the healthy bacteria in your gut while suppressing the growth of bad bacteria.

In addition to promoting healthy bacterial balance, oligosaccharides also have potent anti-inflammatory properties. In one animal study, researchers observed that oligosaccharides in goat’s milk provide protection against colonic inflammation—one ofthe primary causes of irritable bowel syndrome and digestive upset. So by restoring healthy bacterial balance in the gut and simultaneously shutting down gut inflammation, goat’s milk can also eliminate constipation, bloating, and gas during or after workouts.

Barrier #3: Lack of Nutrient Density

Nutrient density is enormously important for an athlete. There is a huge difference between consuming a source of food rich in vitamins, minerals, proteins, and fatty acids to help the body recover versus simply consuming a high amount of calories from a large post-workout pizza or glass of commercial chocolate milk. When it comes to nutrient density, goat’s milk packs a tremendous punch.

Studies have shown that minerals and electrolytes found in goat’s milk—such as calcium, phosphorus, iron, copper, zinc, magnesium, and selenium—are better absorbed and utilized by the body than those same minerals found in cow’s milk. For athletes concerned about muscle function, hydration, and bone density, this is a huge consideration.

But the nutrient density benefits of goat’s milk don’t stop with minerals. Italian researchers have discovered that goat milk stimulates the release of nitric oxide, a potent molecule that causes blood vessels to relax and widen, allowing for faster glucose and oxygen delivery to working muscles.

Goat’s milk is also an excellent source of medium-chain fatty acids, healthy fats that the body can use as an energy source during exercise. Medium-chain fatty acids have also been shown to keep dangerous triglyceride and oxidized cholesterol levels low, thus lowering risk of heart disease or stroke during physical performance.

The vitamin A content of goat’s milk is also higher than that of cow’s milk. Though cow’s milk does contain vitamin A, it comes in the form of carotenoids which need to be converted by your body before they can become vitamin A. When you drink goat’s milk, however, the vitamin A is readily formed and immediately absorbed by the body.

Goat’s milk also has higher amounts of riboflavin (B2) than cow’s milk. Riboflavin assists in the metabolism of proteins and carbohydrates, and strengthens your immune system by stimulating the production of antibodies. Goat’s milk also contains more protein and calcium than cow milk.


Are you concerned about food intolerances or suspicious you may have them? Do you suffer from constipation, bloating, and gas before, during, or after workouts? Do you find that no matter how much you eat, you still get food cravings, run out of energy, or can’t seem to recover quickly?

If so, it’s very likely that at least one—and perhaps all—of the barriers I just described exist in your life. One of the first things you can do to change things for the better is to identify any sources of commercial dairy and cow-derived compounds in your refrigerator, cupboard, recovery powders, or workout beverages and replace them with goat-derived compounds. This is a step I’ve personally taken and it was one of the best things I ever did for my gut, my immune system, and my performance.

Now that you’re equipped with knowledge you need to take action, Go do it!


Ben Greenfield is a champion ironman and performance consultant to Mt. Capra Products, Inc. His podcast can be heard at bengreenfieldfitness.com. Joe Stout, MS, is Mt. Capra’s clinical nutrition scientist. They can be reached at info@mtcapra.com.