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MAXIMAL OXYGEN UPTAKE AND MATURATION IN 12-YEAR-OLD MALE ROWERS
Pavle Mikulić
Lana Ružić
Goran Leko
Sažetak
This study was designed to examine the differences
in VO max between 47 rowers of the same chronological 2
age (12-year-olds; mean ± SD 12,5 ± 0,3), but of varying
levels of physical maturity. VO max was expressed in 2
absolute units (L/min), as the ratio standard mass-related
units (mL/kg/min) and using the allometric model
specific to the data set. Sexual maturity was visually
assessed using indices of pubic hair developed by Tanner.
The subjects were classified in pre-pubertal (Tanner stage
1), early-pubertal (Tanner stage 2), and mid-pubertal
(Tanner stages 3 and 4) groups. They completed an
incremental maximal treadmill test. Differences were
compared using a one-way ANOVA.
VO max (L/min) in 12-year-old rowers proved to be 2
greater in the mid-pubertal group than in both the earlypubertal
(+19,7%) and pre-pubertal (+24,8%) groups.
When expressed as a ratio standard (i.e. in mL/kg/min),
VO max was +12,1% greater in the mid- and pre- 2
pubertals than in the earlypubertals. However, when
compared using the appropriate scaling procedure, the
VO max in mid-pubertal rowers was +14.5% greater than 2
in the early-pubertals, and +9,1% greater than in prepubertals.
This suggests that factors other than body mass
explain the greater aerobic power (as assessed by
VO max) in more physically mature individuals of the 2
same chronological age. Allometric scaling of VO max in 2
the present study yielded a scaling coefficient for body
mass of 0,68 (95% CI = 0,51-0,87). This finding
reinforces the view that, in children, VO max increases 2
relative to body mass raised to the power of 0,67 rather
than in direct proportion with body mass (i.e. mass1,0).
In conclusion, using a log-linear scaling model to
adequately control for body mass, we have demonstrated
significant differences in VO max among 12-year-old 2
rowers of varying stages of puberty and, consequently,
varying levels of maturity. Further research is needed in
order to further explain the above-mentioned differences
among groups of rowers exhibiting differing levels of
maturity independent of body mass.
Ključne riječi
VO2max; physical maturity; young rowers; allometric scaling
Hrčak ID:
14319
URI
Datum izdavanja:
1.7.2007.
Posjeta: 2.290 *