Gollnick P D
Int J Sports Med. 1982 Feb;3 Suppl 1:26-32.
Human skeletal muscle consists of fast and slow twitch motor units. The FT units can be further subdivided into three types on the basis of staining procedures that identify the proteins in the contractile elements. Presently it does not appear that a conversion of motor units occurs with training. Major metabolic differences exist between the different motor units. With endurance training there is an increase in the enzymes for end-terminal oxidation. This reduces the differences between fiber types. This reduction is the differences between fiber types is most dramatic when viewed from histochemical stains. Training does increase the concentration of glycogen stored in the muscle. Muscular strength is related to the total cross-sectional area of the muscle. This can be increased with heavy resistance exercise. This enlargement is due to hypertrophy of the pre-existing fibers and not to a proliferation of fibers as the result of splitting of the fibers.
人类骨骼肌由快肌和慢肌运动单位组成。根据识别收缩元件中蛋白质的染色程序，快肌单位可进一步细分为三种类型。目前看来，运动单位不会因训练而发生转变。不同运动单位之间存在主要的代谢差异。进行耐力训练时，终端氧化酶会增加。这减少了纤维类型之间的差异。从组织化学染色来看，这种纤维类型之间差异的减少最为显著。训练确实会增加肌肉中储存的糖原浓度。肌肉力量与肌肉的总横截面积有关。通过大重量抗阻运动可以增加肌肉总横截面积。这种增大是由于已有纤维的肥大，而非纤维分裂导致纤维增殖的结果。
