EVALUATION OF PHYSICAL-FITNESS FROM FIELD-TESTS AT HIGH-ALTITUDE IN CIRCUMPUBERTAL BOYS - COMPARISON WITH LABORATORY DATA

Field tests of running and laboratory tests were performed in La Paz [high altitude (HA), 3700 m] and in Clermont-Ferrand [low altitude (LA), 300 m] to investigate their validity at HA. Prepubertal boys of mean ages 10.6 years (HA1, n = 16; LA1, n = 28) and pubertal boys of 13.7 years (HA2, n = 12; LA2, n = 41) took part in the study. All the boys performed a 30-m sprint (v(30m)), a 30-s shuttle run (v(30s)) and a progressive shuttle run test until their maximal aerobic velocity (v(maxSRT)). Maximal oxygen consumption was extrapolated from the last test (VO2maxSRT). In the laboratory, the boys performed a force-velocity test (P-max), a Wingate test (P-Wing) and a graded test to measure maximal oxygen consumption (VO2maxB; direct method) on a cycle ergometer. At similar ages, there was no significant difference between HA and LA boys for v(30m) and P-max. The v(30s) of HA boys was 3%-4% lower than those of LA boys (P < 0.05); there was no significant difference for P-Wing. Significant relationships were observed at both altitudes between P-max (watts per kilogram) and v(30m) (HA: r = 0.76; LA: r = 0.84) and between P-Wing and v(30s) (HA: r = 0.67; LA: r = 0.77); the slopes and the origins were the same at HA and LA. The VO2max, v(maxSRT) and VO2maxB were lower by 9%, 12% and 20%, respectively, at HA than at LA (P < 0.05). However, the relationships between VO2maxB and VO2maxSRT (litres per minute) at HA (r = 0.88) and at LA (r = 0.93) were identical. In conclusion, chronic hypoxia did not modify performance in very short dash exercises. The influence of HA appeared when the exercise duration increased and, during a maximal shuttle run test, performance was reduced by 10% at HA. Moreover, it was possible to assess P-max, P-Wing and VO2max at HA as well as at LA from field tests.