β-Hydroxy-β-Methylbutyric acid (HMB) is a metabolite of the essential amino acid L-leucine, with roughly 5% of dietary l-leucine converted into HMB. HMB is best known for supporting skeletal muscle function, particularly in supporting recovery from muscle damage, mitigating muscle protein breakdown, and countering age-related muscle loss.
There are two main forms of HMB used as a dietary supplement. One is a calcium salt (Calcium HMB or CaHMB). The other is a free fatty acid form. We decided to use CaHMB, because it has been the most-studied form of HMB.
For ergogenic purposes (i.e., to enhance sports performance) and to counter muscle wasting syndromes HMB is usually dosed at either 1.5 or 3 grams a day (3 grams is the more common dosage). This is a much larger dose of HMB than what’s made in the body. The capacity to make HMB is influenced by diet. It’s estimated that a healthy adult produces about 0.3 grams (i.e., 300 mg) of HMB per day. A person with a high dietary intake of leucine might make two or three times more, while a diet lower in leucine would result in less. HMB is also affected by age: Our body makes less HMB from leucine as we get older. We selected a dose of HMB intended to support this more physiological HMB range.
Exercise performance (ergogenic effects)
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