Table 2.

The profile of myosin heavy chains and enzyme activities in the arm (triceps brachii) and leg (vastus lateralis) muscles of elite cross-country skiers (n = 10).

	Fiber type distribution (% of total)			Enzyme activity
	MHC-1	MHC-2A	MHC-2X	CS	HAD	HAD/CS
Leg	58 ± 2	41 ± 2	1.0 ± 0.4	118 ± 6	144 ± 12	1.22
Arm	40 ± 3∗	60 ± 3∗	0.4 ± 0.2	111 ± 10	95 ± 12∗	0.84∗

The maximal activities of 3-hydroxy-acyl-CoA-dehydrogenase (HAD) and citrate synthase (CS) are given in μmol/g dw/min. ^∗Significantly different from the leg muscle.