Validation of the counter movement jump test applied to trial cycling and the effect of moderate altitude in its performance

Introducción

Trial is a cycling discipline based on balance across obstacles located within marked zones that require a great explosive strength to overcome these steps jumping with the bicycle in the established areas of competition. As often trial competitions take place in moderate altitudes and the Olympic Games of Mexico in 1968 showed that the explosive athletic jumps could be favoured by the altitude, the objectives of the present study were 1) to validate a test to measure the vertical jump performance objectively using trial bicycle (which is also a specific and many times used competition skill) and 2) to study if moderate altitude could influence the jump performance in this discipline.

Method

Nine elite Trial cyclists (7 men and 2 women) of Spanish National Team participated in the study (world champion team in 2007). First, the subjects carried out 2 sessions of counter movement jumps (CMJ, Ergojump Bosco System) with the aim of validating an objective test of power development for trial cycling discipline. The tests were performed in two separated days. In a third day, the cyclists carried out the same jump test in two separate occasions, one in normoxia (Granada city ~640m) and another under moderate altitude (Sierra Nevada ~2320m). Pearson’s correlations were established for the validation, and to compare the tests in the two altitudes a T test for related samples was used.

Results

The CMJ test was validated showing a good reliability (r=0.95). After the test in moderate altitude, the correlation was similar to the previous tests observed and no statistical differences were found between the two altitudes. Using a simple formula (i.e. Power (W) = (Body weight + bicycle weight) (Kg) x 9.81 x ? [2 x 9.81 x jump height (m)]) we can get an estimation of the specific power developed in this specific skill). For this sample, the average height was 50.5 ± 13.9 cm, with a maximum value of 71.1 cm.

Conclusions

The CMJ test was validated for trial cycling and will allow us to measure in an objective, reliable and sensitive way the specific power development of trial athletes, and to compare the results between different moments and between subjects. The results showed that moderate altitude does not influence the jump performance in trial cycling.