Abstract
We compared results of Special Judo Fitness Test (SJFT) performance of young athletes
of two different age categories after correcting body mass (BM) variations by allometric
scales. Thirty young judokas (14.2±3.6 years) belonging to two age categories underwent
an SJFT: under 15 (U15) years old (12.1±2.4 years; 46.5±15.6 kg; 152.4±11.2 cm) and
under 21 years old (U21) (18.2±0.8 years; 77.1±23.5 kg; 174.2±8.9 cm). Allometric
exponents of −0.33 and 0.67 were used to correct the influence of BM variations on
SJFT performance results. After correction using the –0.33 exponent, U21 showed a
higher number of throws (TNT) than U15 (85.5±9.9 and 68.8±12.0, p<0.05, respectively),
although the SJFT index had been similar between these groups (67.3±10.1 and 61.7±8.1,
p>0.05, respectively). In contrast, TNT normalized by the 0.67 exponent was higher
in U15 than U21 (1.55±0.29 and 1.17 ± 0.25, p<0.05, respectively). Likewise, the SJFT
index was higher in U15 than in U21 when using the same exponent (1.55±0.29 and 1.17±0.25,
p<0.05, respectively). In conclusion, the −0.33 exponent may be useful to remove the
influence of BM variations, thus discriminating SJFT performance results in U15 and
U21 judokas. Moreover, the 0.67 exponent may overestimate SJFT indices in low-age
judokas.
Key words
body mass - young athletes - performance correction - judokas