title: Reproducibility of maximum aerobic power (VO2max) among soccer players using a modified heck protocol.
abstract: OBJECTIVE
  To determine the degree of reproducibility of maximum oxygen consumption (VO2max) among soccer players, using a modified Heck protocol.
  
  
  METHODS
  2 evaluations with an interval of 15 days between them were performed on 11 male soccer players. All the players were at a high performance level; they were training for an average of 10 hours per week, totaling 5 times a week. When they were evaluated, they were in the middle of the competitive season, playing 1 match per week. The soccer players were evaluated on an ergometric treadmill with velocity increments of 1.2 km.h-1 every 2 minutes and a fixed inclination of 3% during the test. VO2max was measured directly using a breath-by-breath metabolic gas analyzer.
  
  
  RESULTS
  The maximum running speed and VO2max attained in the 2 tests were, respectively: (15.6 +/- 1.1 vs. 15.7 +/- 1.2 km.h-1; [P = .78]) and (54.5 +/- 3.9 vs. 55.2 +/- 4.4 ml.kg-1.min-1; [P = .88]). There was high and significant correlation of VO2max between the 2 tests with a 15-day interval between them [r = 0.97; P < .001].
  
  
  CONCLUSIONS
  The modified Heck protocol was reproducible, and the 15-day interval between the ergospirometric testing was insufficient to significantly modify the soccer players' VO2max values.
authors.affiliation: Laboratory for the Study of Movement, Institute of Orthopedics and Traumatology, Hospital das Clínicas, Faculty of Medicine, University of São Paulo, Brazil.
authors.forename: Paulo Roberto
authors.initials: PR
authors.lastname: Santos-Silva
authors.forename: Alfredo José
authors.initials: AJ
authors.lastname: Fonseca
authors.forename: Anita Weigand de
authors.initials: AW
authors.lastname: Castro
authors.forename: Júlia Maria D'Andréa
authors.initials: JM
authors.lastname: Greve
authors.forename: Arnaldo José
authors.initials: AJ
authors.lastname: Hernandez
mesh_terms: D000293:Adolescent; D000328:Adult; D005080:Exercise Test / Q000379:methods*; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D015203:Reproducibility of Results; D012916:Soccer / Q000502:physiology*