Quick answer: EAAs are the nine essential amino acids: the building blocks of protein that your body cannot make on its own, so they have to come from food or supplements. Research points to the essential amino acids, led by leucine, as the part of protein that switches on muscle rebuilding after training. That is why a complete EAA formula does more for recovery than BCAAs alone.*
What are essential amino acids?
Protein is made from 20 amino acids. Your body can build 11 of them from other nutrients. The other nine it cannot make at all, which is why they are called essential. You have to eat them, every day.
The essential nine are:
- Leucine
- Isoleucine
- Valine
- Lysine
- Threonine
- Phenylalanine
- Methionine
- Histidine
- Tryptophan
The first three (leucine, isoleucine and valine) are also known as the branched-chain amino acids, or BCAAs. Every BCAA is an EAA, but BCAAs are only three of the nine.
Why do EAAs matter for recovery?
Every hard session breaks muscle down. Getting stronger happens afterwards, when your body rebuilds that tissue through a process called muscle protein synthesis. To rebuild, it needs all nine essential amino acids on hand.
Research backs this up. A study in the American Journal of Clinical Nutrition gave one group essential amino acids alone and another group essential plus non-essential amino acids. Both groups got the same muscle-building response. The essential amino acids were doing the work [1].
Leucine is the one that gets the process started. The International Society of Sports Nutrition's position stand on protein and exercise names the essential amino acids, and leucine in particular, as the main drivers of muscle protein synthesis. It suggests about 700 to 3,000 mg of leucine per serving [2].*
EAAs vs BCAAs: what's the difference?
BCAAs were the go-to recovery supplement for years, and they still have a place. But leucine can only start the rebuild. It cannot finish the job without the other six essential amino acids. A 2017 review in the Journal of the International Society of Sports Nutrition made exactly this point: with BCAAs alone, the other essential amino acids run out, and that limits how far muscle building can go [3].
| BCAAs | EAAs | |
|---|---|---|
| Amino acids included | 3 (leucine, isoleucine, valine) | All 9 essential amino acids |
| Starts muscle protein synthesis | Yes, via leucine | Yes, via leucine |
| Has all the building blocks to complete it | No | Yes |
| Best for | A leucine hit between meals | Complete recovery support around training |
The simple version: BCAAs tell your muscles to rebuild. EAAs tell them to rebuild and give them everything they need to do it.*
When should you take EAAs?
You can take EAAs before, during or after training. Each option has a reason behind it:
- Before: amino acids are already in your bloodstream when training starts. One early study found a stronger muscle-building response when amino acids were taken before resistance exercise instead of after [4].*
- During: sip them through a long session, especially when you're sweating a lot.
- After: a quick, light option when a full meal is still an hour or two away.
Timing matters less than consistency. The ISSN is clear that total daily protein is the foundation [2]. Use EAAs to fill the gaps around training, not to replace real meals.
Do EAAs help with hydration?
Amino acids on their own don't hydrate you. Water does. What a good EAA drink does is make it easier to drink more during training. That is why Best EAA is mixed into 8 oz of water and includes coconut water powder and potassium, which help support hydration.* On long or very sweaty days, drink more water than that one scoop.
What's in BPI Sports Best EAA?
Best EAA contains all nine essential amino acids in every scoop, with no sugar and just 10 calories:
- 7.2 g of BCAAs in a 2:1:1 ratio: 3,600 mg leucine, 1,800 mg isoleucine, 1,800 mg valine
- The other six essentials: threonine (950 mg), lysine (900 mg), phenylalanine (550 mg), methionine (250 mg), histidine (100 mg), tryptophan (50 mg)
- Hydration support: coconut water powder (200 mg) plus potassium (110 mg)
- 30 servings in two flavors: Lemon Berry and Sour Power
How to use it: mix 1 scoop in 8 oz of water and drink it before, during or after your workout.
Frequently asked questions
What are EAAs?
EAAs are the nine essential amino acids your body cannot make itself: leucine, isoleucine, valine, lysine, threonine, phenylalanine, methionine, histidine and tryptophan. They have to come from your diet or a supplement.
Are EAAs better than BCAAs?
For recovery, a complete EAA formula covers more. BCAAs are three of the nine essential amino acids. They can start muscle protein synthesis, but your body needs all nine to complete it. Most EAA formulas, Best EAA included, already contain a full dose of BCAAs.*
When is the best time to take EAAs?
Before, during or after training all work. Pick the time you can stick to. Consistency and total daily protein matter more than the exact minute.
Do I need EAAs if I eat enough protein?
Food comes first. EAAs are a convenient, low-calorie way to get essential amino acids around training, especially when you train fasted, go a long time between meals, or don't want a heavy shake before a session.
Can I take EAAs on rest days?
Yes. Your body keeps rebuilding muscle on rest days too, so some people take a serving between meals. Follow the directions on the label.
The bottom line
Your body can't make nine of the amino acids it uses to rebuild muscle. EAAs supply all nine. Leucine starts the rebuild and the other eight give your muscles what they need to finish it. Food and total protein come first, and a complete EAA formula helps you make the most of the work you put in.*
Sources
- Volpi E, et al. Essential amino acids are primarily responsible for the amino acid stimulation of muscle protein anabolism in healthy elderly adults. Am J Clin Nutr. 2003;78(2):250-258. PubMed 12885705
- Jäger R, et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20. PubMed 28642676
- Wolfe RR. Branched-chain amino acids and muscle protein synthesis in humans: myth or reality? J Int Soc Sports Nutr. 2017;14:30. PubMed 28852372
- Tipton KD, et al. Timing of amino acid-carbohydrate ingestion alters anabolic response of muscle to resistance exercise. Am J Physiol Endocrinol Metab. 2001;281(2):E197-E206. PubMed 11440894
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.