What is Hypertrophy?

Hypertrophy is the scientific term for an increase in muscle size. It’s a central goal for many people training in the gym, whether they realise it or not. From improving aesthetics to supporting joint health and metabolic rate, hypertrophy plays a vital role in both form and function.

Muscle hypertrophy occurs when muscle fibres are subjected to mechanical tension, usually through resistance training, and are then given adequate nutrition and recovery to rebuild stronger and larger. There are two types of hypertrophy: myofibrillar (increasing the density of muscle fibres) and sarcoplasmic (increasing the volume of fluid and energy substrates in the muscle cells). Most resistance training programs target a bit of both.

Key principles for hypertrophy include progressive overload (gradually increasing the demand on the muscles), sufficient volume (total work performed), and appropriate recovery. Nutrition also matters—particularly protein intake and overall energy availability.

Contrary to popular belief, hypertrophy isn’t about lifting the heaviest possible weight. It’s about controlled, consistent effort with good form, the right intensity, and appropriate rest. And it’s not just for bodybuilders. Hypertrophy supports metabolic health, insulin sensitivity, bone density, and even cognitive resilience.

If you want to age well, perform well, and look the part—hypertrophy training should be part of your routine.