As an avid weightlifter, you know that your body uses amino acids to build muscle protein, which is how your body crafts muscle. You may even be familiar with the differences between complete proteins and incomplete proteins, as well as all the essential and nonessential amino acids. But did you know that aminos do more than build muscle protein, or which ones are most important for bodybuilders to ingest as supplements?

Here we suggest a few you'll want to take before every single workout to boost your energy levels sky-high. That's right--carbohydrates aren't the only nutrient you can consume to provide energy. Besides being critical for muscle growth, certain amino acids can energize you before a workout better than carbs can. Try these three aminos when you want to train with insane intensity, all in the name of muscle growth.

BRANCHED-CHAIN AMINO ACIDS (BCAAs)

Three amino acids are labeled BCAAs -- leucine, isoleucine and valine--and they're critical for energy and muscle growth. Unlike most other aminos, BCAAs are used directly by muscles for fuel during exercise. Yet after the workout's over, muscles rely mostly on stored fat for energy, allowing those BCAAs to be used for hypertrophy. That means taking BCAAs before training will provide you with more energy during the workout, spare your muscle levels of BCAAs (which normally get burned for fuel during exercise) and boost muscle growth even after your gym session is over.

DOSE: Take 5-10 grams immediately before training. Look for products that provide a 2:I:I ratio of leucine to isoleucine andvaline. In other words, a 5-gram dose should contain should contain about 2.5 grams of leucine and 1.25 grams each of isoleucine and valine.

GLUTAMINE

This amino acid can aid energy production in a number of ways. Your muscles can use glutamine to produce more energy while you're resting between sets, which helps you recover better and enhances your strength and endurance on later sets.

Glutamine also helps produce bicar-bonate, which buffers fatigue-producing chemicals that form during intense exercise. In addition, this amino boosts growth hormone levels and frees up more fat from fat cells for enhanced recovery. Glutamine also improves how muscle cells load up on glycogen from dietary carbs, so they can per-form better for longer. It even provides energy for your immune system to run efficiently.

DOSE: Take 5-10 grams immediately before workouts.

CITRULLINE MALATE

This supplement consists of the amino acid citrulline bound to malic acid (malate). In the body, a great deal of citrulline gets converted to the amino acid arginine, which can then enhance nitric oxide production. This boosts blood flow to the muscles, in turn delivering more nutrients and oxygen to increase energy during the workout, not to mention the incredible pump.

Citrulline is also involved in removeing ammonia, a toxic compound that's produced when amino acids are metabolized during intense exercise, from the body. In this way, citrulline delays fatigue during workouts.

Malic acid helps the body convert the lactic acid produced during intense training sessions to energy for the muscles, thus further delaying muscle fatigue. Clinical studies in humans have shown that citrulline malate supplements can help reduce fatigue, boost production of adenosine triphosphate (the major energy currency of all cells) during exercise and increase the rate of creatine phosphate (energy used when lifting weights) recovery following exercise.

DOSE: Take 1-3 grams immediately before workouts.