Bodybuilding Warehouse HMB (Beta-hydroxy beta-methylbutyrate) is an amino acid that is derived from the breakdown of leucine. It has been proven in several studies to slow down the breakdown of muscle protein (i.e. it's anti-catabolic), as well as promote lean muscle growth. Early studies have also demonstrated that HMB supplementation lowers cholesterol, and boosts the immune system.
For these reasons, it makes sense to supplement with HMB during any period where you're training hard, and especially during period of "cutting" or bodyfat loss cycles where muscle loss is a risk, and immunity is suppressed.
Bodybuilding Warehouse HMB is safe and effective to take year round and does not require cycling.