What is Testo DAA? Testo DAA from Applied Nutrition has been created to further your training, intensify workouts & fuel muscle growth. How does Testo DAA work? Testo DAA from Applied Nutrition contains D-aspartic acid, which works by increasing natural testosterone production by up to an incredible 48%. By using Testo DAA you can benefit from increased muscle growth & more intense workouts. To use Testo DAA simply mix ½ teaspoon in 100ml of water or protein shake. Ensure that you do not exceed more than 3 grams per day. Nutritional Information. Not for use by those under 18. 3, 120mg of DAA