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Optimum Nutrition

Optimum Nutrition Amino Energy Powder, Watermelon, 9.5 Oz

Based on 12,805 reviews
Condition: New
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$22.79
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Availability: In Stock.
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Arrives Friday, Oct 30
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At a glance

Condition
New
Flavor
Watermelon
Size
9.5 oz (Pack of 1)
Dimensions
3.54 x 3.54 x 6.3 in
Weight
0.27 kg
Item Form
Powder
Diet Type
Keto

Features 5

  • AMINO BLEND - a perfectly blended mix of amino acids to aid in muscle recovery
  • ENERGY BLEND - 100mg of Caffeine to help boost energy and help you get through the day or a grueling workout
  • MENTAL FOCUS - don't allow the day to get the best of you, the unique formula in ESSENTIAL AMIN.O. ENERGY helps provide you with the mental focus you need
  • ANY-TIME FORMULA - this unique formula is perfect for any time of the day such as helping you get energized and focused in the morning, helping to stay focused and productive in the afternoon, or even supporting your energy levels and focus in the gym

Description

Essential AMIN.O. ENERGY powder mix is a delicious, great-tasting way to add energy and amino acid support to your active lifestyle. Each serving provides 100 mg of caffeine from natural sources, including green tea and coffee bean, to support energy, along with 5 g of amino acids to support post-workout muscle recovery. With 0 g of sugar per serving, it’s an easy choice for active people looking for a refreshing boost before training, during physical activity, or throughout the day. With a variety of delicious fruit-inspired flavors and easy mixing, Essential AMIN.O. ENERGY makes it easy to enjoy your daily energy and amino acid routine. Simply mix with water, juice, or another beverage and enjoy a flavorful drink that fits seamlessly into workouts, sports, and other physical activities. Essential AMIN.O. ENERGY contains no aspartame and is banned-substance tested. It is intended for healthy adults and should be used as part of a balanced diet and exercise program. Because it contains caffeine, follow the recommended serving directions and caffeine warnings on the product label.

Specs 32

Product Dimensions 3.54 x 3.54 x 6.3 inches; 9.52 ounces
Item model number 1046414
Department unisex-adult
Manufacturer Optimum Nutrition - NutWell
Brand Name Optimum Nutrition
Primary Supplement Type Branch Chained Amino Acids
Item Form Powder
Diet Type Keto

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Oct 30

This item is non-returnable:

Non-returnable due to Food safety reasons

View our full returns policy here.

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Top Amazon Reviews

Worth the Try
Flavor Name: Watermelon Size: 9.5 Ounce (Pack of 1)
I purchased this 3 days ago and I really like it!! The taste is good just not flavored enough but it does give me that extra push through without jitters and it doesn't keep me up at night. Although it's smaller than advertised but I like how it's not gritty and dissolves good. I think it's worth it! ... show more
Reviewed in the United States on August 23, 2026 by Gina Bonner
My new "go to"
Flavor Name: Watermelon Size: 9.5 Ounce (Pack of 1)
I bought this for an energy boost in the morning before my work out and absolutely love it so far. I bought the watermelon flavor and it's not super tart nor is it very watered down. I think it's the perfect balance of flavor so it's not very overwhelming in the morning. It's easy to shake up and dissolve. I use a shaker bottle for mine, but I can see it easily dissolving using a handheld frother. Looovvveee the energy boost it gives me. It's not making me feel jittery at all. The boost isn't super slow nor is it going to hit you all at once. I drink this about ~15 minutes before I work out. I used to use the Amino Lean brand, but I'm loving this one a lot more. I plan to get some other flavors too! :) ... show more
Reviewed in the United States on September 30, 2026 by Emily
Need Clean Energy? Here’s Your Product!
Flavor Name: Watermelon Size: 1.29 Pound (Pack of 1)
Review Image by Austin
I can’t say enough good things about ON Amino Energy. I work out 6 days a week and switched to ON Amino Energy after using several different designated pre workouts. ON Amino Energy blows those pre workouts out of the water! I get just as much energy, if not more, from this product over designated pre workout drinks. The energy also feels super clean, like you’re not over stimulated or jittery. I also feel like I actually have more stamina during my workouts with this over the other pre workouts I have tried. This product mixes very well, no clumping. Tastes great. I use 2 scoops per workout and it is more than enough to get through 30-45 min HIIT workouts. Can’t recommend this enough! ... show more
Reviewed in the United States on May 23, 2026 by Austin
Great pre workout with a delicious flavor
Flavor Name: Watermelon Size: 9.5 Ounce (Pack of 1)
I absolutely love this pre-workout and the watermelon flavor tastes great. This gives me the perfect boost of energy before my workouts without making me feel jittery or causing the tingling sensation that some pre-workouts do. It helps me feel focused and ready to train without being overwhelming. This has become my go-to pre-workout, and I love, love, love it! I’ll definitely keep buying it and highly recommend it to anyone looking for clean, smooth energy. ... show more
Reviewed in the United States on July 9, 2026 by Kandace Salchenberg
First Single Serving, Good Little Energy Boost, Good Taste, Good Presentation *UPDATE
Flavor Name: Watermelon Size: 1.29 Pound (Pack of 1)
So, for right now, I'm going to leave a 4-star review, only because I've just received it, and I haven't had a chance to use it for the reason I bought it for, which is to replace sugar-free Monster energy drinks that I would buy everyday before clocking in at work. I'm testing out a single serving of it now, and will update at the end of this upcoming work week. I'll leave a few initial thoughts, for now: 1. I like the presentation of the bottle; clean and precise, informative. 2. The powder, itself, is very fine and dense. I had to give it a little shake to loosen it up a bit. Reaching in to pull the scoop out left a couple finger tips covered in the super fine powder. Not a big deal, just don't spill it on accident. 3. Because of it's density it takes a short bit to get it all dissolved and mixed in, maybe 20 seconds for a couple scoops. The taste is a mild, refreshing flavor. It's not too tart, not too watered down, and easy to swig down. I'm not noticing an overpowering artificial flavor, it's pretty nice, and it doesn't give much of an aftertaste. EDIT: For this particular flavor, there is a very funky aftertaste; almost like morning mouth, or something, lol. 4. I'm getting a bit of an energy pep that isn't making me jittery, or ramping up my heart rate, but I've only taken a single serving of it (100 mg). It's probably good for a small pick-me-up, here and there. EDIT: Energy boost was good. It took my body a while to adjust to using it, after using popular energy drinks. I usually took about 150mg per serving, which is about one can of Monster, and the energy felt a bit cleaner, healthier. It's okay. So far, it's not bad. As I stated, I'll make an update after a week of using more of it before and during work. EDIT 01: I'm going to stick with the 4-star review, for now, and try out the Blue Raspberry flavor. I certainly saved more money, per day, as compared to what I'd spend on other energy drinks. EDIT 02: Blue Raspberry was good. Same points as before, but, for me, there is much less of a nasty aftertaste. I'd recommend this flavor before the Watermelon, absolutely. Pleased with Blue Raspberry; I'll buy it again :) ... show more
Reviewed in the United States on August 9, 2025 by Jason R Lattergrass
Works wonders
Flavor Name: Watermelon Size: 9.5 Ounce (Pack of 1)
I have been using this stuff for about 10 years and absolutely love it. There are multiple different flavors to try. Take as directed, 1 scoop per day is all I needed. If I take more than one and after a certain time of day, it does keep me awake. I just add a scoop to my water bottle shake until it dissolves, easy to digest. When my mom was diagnosed with cancer, she drank this stuff everyday and never had side effects from her chemo treatments ... show more
Reviewed in the United States on July 23, 2026 by Teresa
Optimum Nutrition Amino Energy – Watermelon Flavor – A Perfect Boost!
Flavor Name: Watermelon Size: 9.5 Ounce (Pack of 1)
I’ve been using Optimum Nutrition Amino Energy as my go-to pre-workout for a few weeks now, and I’m really impressed! Here’s why: Amazing Taste: The Watermelon flavor is absolutely delicious! I’ve tried a lot of pre-workouts in the past, and this one stands out in terms of taste. It’s refreshing and fruity without being too sweet or overpowering. Definitely a treat to look forward to before my workouts. Energy Boost: This pre-workout gives me a clean and sustained energy boost thanks to the Green Tea and Green Coffee Extract. I feel energized without the jittery crash that some other products give me. It’s perfect for both early morning workouts and mid-day training sessions when I need that extra kick. Supports My Keto Lifestyle: As someone who follows a keto-friendly diet, I appreciate that this product fits into my routine without any guilt. It helps me power through my workouts without kicking me out of ketosis, which is a huge bonus. BCAAs & Amino Acids: The addition of BCAAs and Amino Acids is a major plus. I feel like I’m getting that extra support for muscle recovery, which has been helping me push harder in my workouts while reducing muscle soreness afterward. Convenient and Effective: With 30 servings in the container, it’s great value for the price. Plus, I love that it mixes easily with water—no clumps or weird texture, just smooth, refreshing flavor every time. ... show more
Reviewed in the United States on April 14, 2025 by Amazon Customer
Perfectly pink Starburst, my go to every time
Flavor Name: Watermelon Size: 9.5 Ounce (Pack of 1)
Excellent, don't drink before bed. Tastes like a pink Starburst, delightful without the tingles. Can't reccomend enough.
Reviewed in the United States on August 22, 2026 by Eldritch
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