Biology 105
Biology of Exercise
Spring 2003

Table of human myosin isoforms

Myosin isoform	maximum shortening velocity (length per second)	maximal tension (force) (kiloNewtons/square meter)	ATP breakdown rate (micromoles / second)
MHC1	0.26	64	43
MHC2a	1.12	84	107
MHC2x/b	2.42	98	166

data from Reggiani C. et al. Sarcomeric muscle isoforms: fine tuning of a molecular motor. NIPS 15:26-33, 2000.