Longitudinal splitting of a muscle fibre, which may increase the total number of muscle fibres. It has been suggested that fibre-splitting takes place in response to overload and contributes to muscle growth by hyperplasia. However, although some animal experiments support the concept of fibre splitting, the general belief is that adult human fibre number is established at birth, or shortly after birth, and that no net increase occurs as a result of strength training. See also myofibril splitting.
Subjects: Sports and Exercise Medicine.