- Increased myofibre or whole muscle diameter
- Caused by increased work load on myofibres:
- Work hypertrophy
- Increased physiological work
- Due to training, pregnancy
- Compensatory hypertrophy
- Increased work due to loss or abscence of other fibres
- Can result from denervation or cachetic atrophy, muscular dystrophies or extensive necrosis
- Myofilaments are added -> diameter increases
- Increased work load -> longitudinal splitting of fibres within one endomysial tube
- Work hypertrophy