Rampinini E1, Sassi A1, Azzalin A1, Castagna C2, Menaspà P1, Carlomagno D1, Impellizzeri FM3,4

1, Human Performance Laboratory, MAPEI Sport Research Center, Castellanza;2, School of Sport and Exercise Sciences, University of Rome Tor Vergata, Rome, Italy;3, Neuromuscular Research Laboratory, Schulthess Clinic, Zurich, Switzerland,4; CeBiSM, Research Centre for Bioengineering and Motor Sciences, Rovereto, Italy

The physiological determinants of performance in two Yo-Yo intermittent recovery tests (Yo-YoIR1 and Yo-YoIR2) were examined in 25 professional (n = 13) and amateur (n = 12) soccer players. The aims of the study were (1) to examine the differences in physiological responses to Yo-YoIR1 and Yo-YoIR2, (2) to determine the relationship between the aerobic and physiological responses to standardized high-intensity intermittent exercise (HIT) and Yo-Yo performance, and (3) to investigate the differences between professional and amateur players in performance and responses to these tests. All players performed six tests: two versions of the Yo-Yo tests, a test for the determination of maximum oxygen uptake (VO2max), a double test to determine VO2 kinetics and a HIT evaluation during which several physiological responses were measured. The anaerobic contribution was greatest during Yo-YoIR2. VO2max was strongly correlated with Yo-YoIR1 (r = 0.74) but only moderately related to Yo-YoIR2 (r = 0.47). The time constant (tau) of V(O)(2) kinetics was largely related to both Yo-Yo tests (Yo-YoIR1: r = 0.60 and Yo-YoIR2: r = 0.65). The relationships between physiological variables measured during HIT (blood La, H+, HCO3 and the rate of La accumulation) and Yo-Yo performance (in both versions) were very large (r > 0.70). The physiological responses to HIT and the tau of the V(O)(2) kinetics were significantly different between professional and amateur soccer players, whilst VO2max was not significantly different between the two groups. In conclusion, VO2max is more important for Yo-YoIR1 performance, whilst tau of the VO2 kinetics and the ability to maintain acid-base balance are important physiological factors for both Yo-Yo tests.

Eur J Appl Physiol. 2010 Jan;108(2):401-9.