What this suffix does
The suffix -trophy comes from Greek "trophe" (nourishment, food, growth) and indicates the nutritional or developmental state of a tissue or organ. With prefixes showing excess, deficiency or malfunction, it forms precise medical terms:
atrophy = a- (without): without nourishment → wasting/loss of tissue
hypertrophy = hyper- (excess): excess growth → enlargement
dystrophy = dys- (bad): faulty nourishment → progressive deterioration
Spanish: atrophy → atrofia, hypertrophy → hipertrofia, dystrophy → distrofia.
The three key concepts
atrophy: reduction or wasting of a muscle or organ due to lack of use, nourishment or disease. "Muscle atrophy" = muscle loses mass. "His muscles atrophied after weeks in bed."
hypertrophy: enlargement of an organ or tissue due to increase in cell size. "Cardiac hypertrophy" = the heart enlarges. In fitness: "muscle hypertrophy" = what strength trainers aim for (muscle grows from resistance training).
dystrophy: progressive deterioration due to defective nourishment or function. "Muscular dystrophy" = genetic disease causing progressive muscle weakening. Best known: Duchenne muscular dystrophy.
Hypertrophy in fitness: modern everyday use
"Hypertrophy" has moved from medical language into everyday fitness and sport:
"Hypertrophy training" = training specifically to increase muscle size (not just strength).
"Sarcoplasmic hypertrophy" vs "myofibrillar hypertrophy" = two types of muscle growth.
If you listen to English fitness podcasts or read gym articles, "hypertrophy" is ubiquitous. So is "atrophy": "if you stop training, your muscles will atrophy."