Creatine HMB vs Monohydrate: What 3 Head-to-Head Trials Found

Search for creatine HMB and most of what comes back is written by companies that sell it. The pages compare “creatine HMB” with “creatine monohydrate” as if they were two forms of the same thing, and that framing is where the confusion starts.

Creatine HMB is two supplements, not a new creatine

There is no single molecule called creatine HMB in the research. Products sold under that name combine two separate ingredients: creatine monohydrate, the most studied form of creatine, and HMB (β-hydroxy-β-methylbutyrate), a compound the body makes from the amino acid leucine.

So the honest comparison is not creatine HMB against creatine. It is creatine alone against creatine plus HMB. That turns the question into two smaller ones that the research can actually answer: what does creatine do, and what does HMB add on top of it?

What creatine monohydrate does on its own

Creatine has the stronger evidence of the two by a wide margin. A 2025 meta-analysis in Nutrients pooled 69 randomised trials with 1,937 participants. Paired with resistance training, creatine improved bench and chest press strength by 1.43 kg and squat strength by 5.64 kg more than placebo, along with vertical jump and peak power.

It is not unlimited. In the same analysis, leg press strength and handgrip did not differ significantly from placebo overall. The effect is real, modest, and tied to training. We cover the rest of the creatine evidence, including the kidney and bloating myths, in Creatine: The Real Benefits, and the Myths That Won’t Die.

What HMB does on its own

HMB’s evidence splits sharply by who takes it.

In people who already train, it does very little. A 2018 meta-analysis in the Journal of Science and Medicine in Sport pooled six randomised trials in 193 trained and competitive athletes. The effect sizes were trivial and non-significant for everything measured: bench press 0.00, leg press 0.09, and no meaningful change in fat-free mass or fat mass. The authors’ conclusion was blunt: no effect of HMB supplementation on strength and body composition in trained and competitive athletes. A 2020 meta-analysis in Nutrients found the same in young people generally.

In people who are losing muscle, it looks different. In a 2013 trial in Clinical Nutrition, older adults on ten days of strict bed rest who took 3 g of HMB a day lost 0.17 kg of lean mass, against 2.05 kg in the placebo group. HMB works mainly by slowing muscle breakdown, which is why it shows up when breakdown is high and disappears when it is not.

The three trials that tested the combination against creatine alone

These are the studies that answer the question the search is really asking. There are only three, all small, and they do not agree.

Trial	Who	Length	Creatine plus HMB vs creatine alone
Jówko, 2001	40 people starting weight training	3 weeks	Effects added up: lean mass +1.54 kg vs +0.92 kg over placebo
Fernández-Landa, 2020	28 elite rowers, 7 per group	10 weeks	Higher aerobic power at one lactate threshold; no difference in muscle mass
Rugby season study, 2020	16 collegiate rugby players	6-week crossover	No added benefit; one knee-strength measure fell with the combination

The one clearly positive result, Jówko and colleagues, lasted three weeks and measured lean mass with bioelectrical impedance, a method that is sensitive to the water creatine pulls into muscle. Strength gains above placebo were 39.1 kg with creatine alone and 51.9 kg with both, across all exercises combined.

The rowing study ran longer and found a genuine difference in aerobic power at 8 mmol of blood lactate, but with seven people per group, and with no difference in body composition.

The rugby study, the most recent, gave players 5 g of HMB plus 5 g of creatine or 5 g of creatine plus placebo across a season. Its conclusion: the combination does not provide a greater ergogenic benefit than creatine alone. During the autumn phase, knee extensor peak torque dropped by about 41 Nm in the combination group while it held steady on creatine alone.

Put together, three trials with at most eleven people in a group give no consistent sign that adding HMB to creatine builds more muscle.

The older-adult trial everyone will cite

Two papers published in 2026, in GeroScience and Aging Clinical and Experimental Research, report that creatine plus HMB improved strength, gait speed, sit-to-stand and Timed Up and Go results in active adults over 60. They are easy to read as two confirming studies. They describe the same design: 30 people, 20 men and 10 women, two six-week phases separated by a three-week washout.

More importantly, the comparison was creatine plus HMB against placebo, with everyone doing the same exercise programme. There was no creatine-only group. The trial shows that the combination helped more than nothing. It cannot show whether the HMB contributed anything beyond the creatine, which has its own evidence in older adults.

Which one to buy

For someone who trains and wants more strength, the evidence points to plain creatine monohydrate at 3 to 5 g a day. It has the large trial base behind it, and buying it alone means you are not paying for an ingredient whose added value, in trained people, has not been shown.

HMB earns a separate place in a narrower situation: older adults who are losing muscle, people recovering from illness, and anyone facing bed rest. There, the studied dose is 3 g a day of HMB on its own, and whether to add creatine to it is a reasonable conversation with your doctor rather than something a combined tub settles for you.

If you do buy a creatine HMB product, check the label for the actual amounts of each ingredient per daily serving and compare them with the doses in the trials above: 3 to 5 g of creatine and 3 g of HMB.