BERGH, ULF, ALF THORSTENSSON, BERTIL SJÖDIN, BODIL HULTEN, KARIN PIEHL, and JAN KARLSSON. Maximal oxygen uptake and muscle fiber types in trained and untrained humans. Med. Sci. Sports. Vol. 10, No. 3, pp. 151-154, 1978.—Maximal oxygen uptake (V̇o2 max) was determined in 138 male and 41 female human subjects and muscle fiber composition (gastrocnemius and vastus lateralis) in 53 of the males. Highest values for V̇o2 max were 7.38 1x min-1 and 4.34 l x min-1 in males and females, respectively. In relation to body weight the highest values were 94 and 77 ml x (kg x min)-1. Athletes participating in endurance events had very high V̇o2 max and predominantly slow twitch (ST) fiber populations whereas weight lifters attained rather low values for V̇o2 max and had a higher percentage of fast twitch (FT) fibers. Among subjects with the same fiber composition, V̇o2 max was higher in the athletes than in the moderately trained. All groups taken together demonstrated a positive relationship between V̇o2 max and the relative number of ST fibers (r = 0.67). For endurance and strength athletes r = 0.72 and for the moderately trained r = 0.34, both correlation coefficients being significant.
ENDURANCE, STRENGTH, SKELETAL MUSCLE FIBER TYPES, MAXIMAL OXYGEN UPTAKE, GENETIC FACTORS