Stim-Free Pre-Workout: Inside Birds of Prey’s 5 g goBHB Formula

A stim-free pre-workout used to mean a pump product you took when you’d already maxed out on caffeine for the day. Most of them felt like flavored water with citrulline. Birds of Prey from CleanForm Nutrition is built differently: zero caffeine, 5 grams of goBHB® per scoop, plus creatine, citrulline and glycerol. It’s aimed squarely at people who lift after work and still want to sleep that night.

I want to be upfront about my angle. goBHB Labs supplies the goBHB in Birds of Prey, so I have a stake in this product. That’s exactly why I’m going to walk through the label line by line, tell you which ingredients have strong human evidence and which ones are brand claims, and show you where the research on BHB and sleep actually stands.

Birds of Prey by CleanForm Nutrition: 20 servings, Watermelon Lemonade or Strawberry Lemonade, $39.99 on the brand’s site.

Why a Stim-Free Pre-Workout Makes Sense for Evening Training

Many stim pre-workouts carry a heavy dose of caffeine per scoop. That’s fine at 7 AM. At 6 PM it’s a different story. In a 2013 study in the Journal of Clinical Sleep Medicine, Christopher Drake and colleagues gave 12 healthy sleepers 400 mg of caffeine at bedtime, 3 hours before bed, or 6 hours before bed. Even the 6-hour dose cut objectively measured sleep by more than an hour, and the participants mostly didn’t notice.

Picture the typical after-work lifter: a stim-heavy scoop at 5:30, a hard session and then lying awake at midnight. Taking caffeine out of the pre-workout doesn’t make you stronger on its own, but it removes the trade-off between a good session and a good night’s sleep.

Birds of Prey Ingredients and Doses

Here is what one 26 g scoop delivers, taken straight from the supplement facts panel. The label calls for one scoop in 12 to 16 oz of water about 30 minutes before training.

What’s in one scoop of Birds of Prey

Grams per 26 g serving, from the supplement facts label. Caffeine: 0 mg.

L-citrulline8 ggoBHB (Na, Ca, Mg, K BHB)5 gCreatine monohydrate (Pürest)5 gBetaine anhydrous2.5 gHydroPrime (65% glycerol powder)2 gSetria L-glutathione0.2 gAstraGin0.05 g

Source: Birds of Prey supplement facts panel, cleanformnutrition.com (checked October 25, 2026).

goBHB: 5 g

Five grams is a meaningful dose. It matches a single 5 g serving in the KETAD trial (Nutrients, 2025), where overweight adults took 5 g of BHB salts twice a day for 8 weeks alongside a calorie deficit. In Birds of Prey the goal is different: a fuel source that doesn’t rely on stimulants. CleanForm describes it as steady cellular energy without the jitters, which is a fair summary of why we built goBHB, but I’d call that the brand’s positioning rather than a proven pre-workout effect. Our own lab work on BHB and the caffeine crash is still in cell culture, and you can read exactly what it did and didn’t show in our caffeine crash study write-up.

Creatine monohydrate: 5 g

Creatine is the best-supported ingredient on this label. The International Society of Sports Nutrition position stand (Kreider and colleagues, 2017) calls creatine monohydrate the most studied and clinically effective form, and lists 3 to 5 g per day as a maintenance dose after loading, or as a daily dose that fills muscle stores over about 3 to 4 weeks without loading. Five grams per scoop covers that, as long as you also take it on rest days. For more on pairing the two, see why goBHB and creatine make a strong stack.

L-citrulline, glycerol, betaine and the rest

Eight grams of L-citrulline is a generous dose, and CleanForm includes it for pumps and blood flow. HydroPrime is a stabilized glycerol powder that brands use for hydration and endurance, and betaine anhydrous at 2.5 g is the brand’s power ingredient. Setria glutathione (200 mg) is included to support nitric oxide, and AstraGin (50 mg) for nutrient absorption. Those are the brand’s descriptions. I’m not going to dress them up with study numbers I haven’t checked against this exact formula.

The full Birds of Prey label. Note the mineral line items that come with the goBHB salts.

The Minerals You Get With 5 g of goBHB

goBHB is a BHB mineral salt, so every scoop carries electrolytes along with the ketones. Sodium is the one to count if you’re watching your intake.

Mineral (from goBHB)Per scoop% Daily ValueSodium350 mg15%Calcium255 mg20%Potassium100 mg2%Magnesium90 mg21%

In the KETAD trial, 10 g a day of BHB salts for 8 weeks produced no adverse changes in blood pressure, heart rate or kidney markers in overweight adults. That said, if you’re on a sodium-restricted diet, have kidney problems or take blood pressure medication, check with your doctor before adding any mineral salt product. The label says to check with a physician first if you’re pregnant, nursing, under 18, taking medication or have a medical condition.

Can a Pre-Workout With BHB Support Sleep?

CleanForm’s product page says ketone metabolism supports deeper, more restorative sleep. Here is what the human data on that question looks like. In a 2025 trial in Bioscience, Biotechnology, and Biochemistry, Katsuya and colleagues gave 90 healthy adults with fatigue and poor sleep scores 1.5 g or 2.9 g of D-BHB one hour before bed for 14 days. Compared with placebo, both doses improved self-rated sleepiness on rising, and the lower dose improved ratings for falling and staying asleep. Total sleep time didn’t change.

That study was funded by Osaka Gas, used a questionnaire rather than lab sleep measurements, and gave D-BHB an hour before bed, not a BHB salt blend two or three hours earlier. So I won’t tell you Birds of Prey improves sleep. What I will say is that a caffeine-free pre-workout avoids the well-documented sleep cost of evening caffeine, and the early BHB sleep research points in an encouraging direction. We covered the Katsuya data in more depth in our post on D-BHB and sleep quality.

Who Birds of Prey Fits (and Who It Doesn’t)

It fits evening lifters, anyone who’s caffeine sensitive, and people already getting caffeine from coffee who don’t want to stack more. If you train early and want stimulation, CleanForm suggests adding an espresso yourself, which is a sensible way to control the dose. It’s a weaker fit if you want a strong, immediate stimulant kick. You won’t get that here, by design. For the rest of the goBHB lineup, from cans to shots, see our 2026 goBHB products guide.

CleanForm’s pitch for Birds of Prey: all of the pre-workout, none of the caffeine.

Where the Evidence Stands

Creatine at 5 g a day has strong human support for high-intensity exercise capacity and lean mass when taken daily. Evening caffeine has clear human evidence of disrupting sleep, which is the problem a stim-free pre-workout solves. For BHB, the KETAD trial found 10 g a day of BHB salts well tolerated for 8 weeks, though its body composition changes did not differ significantly from placebo, and a small D-BHB study points to possible sleep benefits. Research on BHB as pre-workout energy is still early. The KETAD trial was funded by Ketone Labs (now goBHB Labs), and the sleep study by Osaka Gas. None of these products are meant to treat or prevent any disease.

FAQ

What is the best stim-free pre-workout?

Look for full doses of ingredients with human evidence and a label that shows the dose of each key ingredient. Birds of Prey lists an amount for every ingredient, including 5 g of creatine, 8 g of citrulline and the 5 g goBHB blend, and has zero caffeine.

Does Birds of Prey have caffeine?

No. Birds of Prey contains 0 mg of caffeine and no other stimulants on the label. CleanForm left caffeine out on purpose so you can add your own if you want it.

Can I take a pre-workout at night and still sleep?

With a caffeinated product, often not: 400 mg of caffeine taken even 6 hours before bed cut sleep by more than an hour in the Drake study. A caffeine-free formula removes that problem, though individual responses vary.

Is it safe to take creatine and BHB together?

Creatine has a long safety record at 3 to 5 g a day, and 10 g a day of BHB salts was well tolerated for 8 weeks in overweight adults in the KETAD trial. If you have kidney issues, high blood pressure or take prescription medication, talk to your doctor first.

The Bottom Line

Birds of Prey is the stim-free pre-workout I’d hand to someone who trains after work and is tired of trading sleep for a good session. The creatine dose is right, the label lists every dose, and 5 g of goBHB gives it a fuel source that doesn’t come from stimulants. Just know which parts are proven and which are promising, and go in with realistic expectations.

Sources: Drake C, et al. Caffeine Effects on Sleep Taken 0, 3, or 6 Hours before Going to Bed. J Clin Sleep Med. 2013;9(11):1195-1200. Kreider RB, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017;14:18. Katsuya S, et al. Effect of d-β-hydroxybutyrate on sleep quality in healthy participants: a randomized, double-blind, placebo-controlled study. Biosci Biotechnol Biochem. 2025;89(5):769-775 (funded by Osaka Gas). Roeth EJ, et al. Effect of Exogenous Ketones as an Adjunct to Low-Calorie Diet on Metabolic Markers. Nutrients. 2025;17(22):3582 (funded by Ketone Labs). Product label and description from CleanForm Nutrition.