What are the Benefits of Taking Amino Acid (BCAA) Supplements?
Amino acids are divided into two categories: essential and nonessential amino acids. There are nine essential amino acids that we must get from food. The remaining nonessential amino acids are also important, but if they are not supplied by the food we eat, they can be manufactured by our body. All of the amino acids are vital to good health. In fact, a lack of just one amino acid will, over time, cause serious health problems.
Below is a list of the 20 Essential and Non Essential amino acids:
To Use or Not to Use Branched Chain Amino Acids (BCAA)
Branched Chain Amino Acids include three of the eight essential amino acids, and they are: leucine, isoleucine, and valine. BCAA accounts for 35–40% of the dietary essential amino
acids in body protein and 14–18% of the total amino acids in
muscle proteins.  BCAA have anabolic effects, and also helps increase protein synthesis in human muscles. I'm sure many will have wondered at some point of what's the point of taking amino acid supplements, since amino acids are building blocks of protein, why not just get your amino acids from your protein? Good question.
When it comes to the question of amino acid supplements vs. protein supplements, there's quite a few clinical studies that provide rather conflicting evidence. There are many studies that have found beneficial effects of branched chain amino acids, including:
BCAA are useful for muscle recovery following exercises, and attenuate muscle damage and decreases delayed onset muscle soreness (DOMS) following exercise
Essential amino acids stimulate muscle protein anabolism by increasing protein synthesis after resistance exercise [2, 4]
Branched chain amino acids have anabolic effects on protein metabolism by increasing the rate of protein synthesis and decreasing the rate of protein degradation, and BCAA also activates key enzymes in protein synthesis after physical exercise 
At the same time, there are a few studies that have found no additional benefits of taking amino acid supplements over simply using a protein supplement.
It was found that whey protein with added leucine did not result anabolic response that is greater than whey protein alone 
Whey protein ingestion was found to improve skeletal muscle protein accrual greater than essential amino acids in older individuals. 
Benefits of Branched Chain Amino Acid Supplements
Exercise results in enhanced BCAA catabolism, and would therefore increase the need for BCAAs. Supplementing branched chain amino acids prior to exercise attenuates the breakdown of muscle protein during exercise, and also attenuate muscle damage induced by exercises. A Japanese study titled "Nutraceutical Effects of Branched-Chain Amino Acids on Skeletal Muscle" has found that taking BCAA supplement prior to exercise decrease DOMS and muscle fatigue, and that taking BCAA supplements can be useful to aid muscle recovery. 
Branched chain amino acids also have anabolic effects. It helps increase protein synthesis and have anabolic effects in human muscle during recovery from exercise. In a study involving six human subjects, a drink consisting of 6g essential amino acids and 35g sucrose) or a placebo drink were administered. The study found that protein synthesis was significantly increased in the amino acid drink group but not for the placebo group. 
Amino Vital Amino Supplement Review
There are plenty of amino acid supplements on the market. Amino Vital is a popular and widely used amino supplement. Having used several Amino Vital supplements, I can say that they've helped increase endurance and also sped up recovery times after intense workouts. Their proprietary blend of amino acids include glutamine and the BCAAs leucine, isoleucine, and valine.
1. Nutraceutical Effects of Branched-Chain Amino Acids on Skeletal Muscle
Yoshiharu Shimomura,4 Yuko Yamamoto,Gustavo Bajotto,Juichi Sato,
Taro Murakami, Noriko Shimomura,z Hisamine Kobayashi, and Kazunori Mawatariyy
2. J Appl Physiol. 2000 Feb;88(2):386-92.Related Articles
An oral essential amino acid-carbohydrate supplement enhances muscle protein anabolism after resistance exercise.
Rasmussen BB, Tipton KD, Miller SL, Wolf SE, Wolfe RR
3. J Nutr. 2006 Jan;136(1 Suppl):269S-73S.
Branched-chain amino acids activate key enzymes in protein synthesis after physical exercise.
Blomstrand E, Eliasson J, Karlsson HK, Köhnke R.
4. Am J Physiol Endocrinol Metab. 2004 Mar;286(3):E321-8. Epub 2003 Oct 28.
Amino acid ingestion improves muscle protein synthesis in the young and elderly.
Paddon-Jones D, Sheffield-Moore M, Zhang XJ, Volpi E, Wolf SE, Aarsland A, Ferrando AA, Wolfe RR.
5. Appl Physiol Nutr Metab. 2009 Apr;34(2):151-61. Links
Stimulation of muscle anabolism by resistance exercise and ingestion of leucine plus protein.
Tipton KD, Elliott TA, Ferrando AA, Aarsland AA, Wolfe RR.