1. You'll Get Muscle-Building Amino Acids
The Paleo Diet is high in animal protein, which is the richest source of branched-chain amino acids (BCAA) like valine, leucine, and isoleucine. Branched-chain amino acids specifically are potent stimulants for building and repairing muscle.
However, keep in mind that these amino acids work best when consumed in the post-exercise window. In other words, you should be eating meat after those heavy workouts!
Lean meats and fish are far and away the greatest source of BCAA. A 1,000-calorie serving of lean beef provides 33.7 grams of BCAA, whereas the same serving of whole grains supplies a paltry six grams.
Because many endurance athletes focus on starches (breads, cereals, pasta, rice, and potatoes) and sugars at the expense of meats, particularly following a hard workout, they get precious little muscle-building BCAA in their diets. By consuming high amounts of animal protein (and hence BCAA) along with sufficient carbohydrates, athletes can rapidly reverse the natural breakdown of muscle that occurs following a workout and thereby reduce recovery time and train at a greater intensity at the next session.
2. You'll Neutralize Your Blood Acidity
Eating Paleo also prevents muscle protein breakdown because it produces a net metabolic alkalosis.
What does this mean, exactly? All foods, upon digestion, report to the kidney as either acid or alkali (base). The typical American diet is net acid-producing because it's high in acid-yielding grains, cheeses, and salty processed foods instead of base-producing fruits and veggies. The athlete's body is even more prone to blood acidosis, or high acidity, due to the by-products of exercise.
One way the body neutralizes a net-acid-producing diet is by breaking down muscle tissue. Because the Paleo Diet is rich in fruits and veggies, it reverses the metabolic acidosis produced by the typical grain-and starch-laden diet that many athletes consume, preventing muscle loss.
3. You'll Get More Trace Nutrients
Fruits and vegetables are rich sources of antioxidant vitamins, minerals, and phytochemicals. When eaten with fresh meat and seafood (excellent sources of zinc and B vitamins), it promotes optimal immune-system functioning.
The refined grains, oils, sugars, and processed foods that represent the typical staples for most athletes are nearly devoid of these trace nutrients. By examining the training logs of numerous people he has coached, my colleague and co-author, Joe Friel (an internationally known triathlete coach), has found that the frequency and duration of colds, flu, and upper respiratory illnesses are reduced when athletes adopt The Paleo Diet. A healthy athlete, free of colds and illness, can train more consistently and intensely, thereby improving performance.
4. Your Muscles Will Replenish Glycogen Stores Faster
One of the most important goals of any athletic diet is to maintain high muscle stores of glycogen, a body fuel absolutely essential for high-level performance. Dietary starches and sugars are the body's number one source for making muscle glycogen. Protein won't do, and neither will fat. Athletes and sports scientists have known this truth for decades. Regrettably, they took this concept to extremes, and high-starch, cereal-based, carbohydrate-rich diets were followed with near-fanatical zeal instead.
It is a little-known fact, but similar to the situation with branched-chain amino acids, glycogen synthesis by muscles occurs most effectively in the immediate post-exercise window. Muscles can build all the glycogen they need when they get starch and sugar in the narrow time frame following exercise. Eating carbs all day long is overkill, and actually serves to displace the muscle-building animal proteins and alkalinity-enhancing, nutrient-dense fruits and veggies that are needed to promote muscle growth and boost the immune system.
Many Paleo-friendly fruits and veggies are effective in restoring muscle glycogen, particularly net-alkaline-producing starches found in bananas, sweet potatoes, and yams.
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