title: Physiological Responses of General vs. Specific Aerobic Endurance Exercises in Soccer.
abstract: OBJECTIVE
  The study aimed to compare the physiological and perceptual responses of two high intensity intermittent aerobic exercises (HIIE), i.e. the 15s/15s exercise and an exercise on the Hoff track (HTE).
  
  
  METHODS
  In this within-subject repeated measures study, seven high-level soccer players (Age: 24.1± 4.5yr; Height: 175± 0.04cm; Body mass: 67.9± 9.0kg;% Body fat: 14.2± 2.4%) performed the two exercises with same total duration (25 minutes) in a randomized order: 1) a 15s/15s protocol at 120% of maximal aerobic speed (MAS), and 2) HTE. Heart rate (HR) and oxygen uptake (VO2) were measured continuously throughout both exercises. The rating of perceived exertion (RPE) was measured 15 min after the end of each exercise. Blood lactate concentration ([La]) was measured at rest before each exercise, between and at the end of each set.
  
  
  RESULTS
  The mean VO2 during HTE was significantly higher than 15s/15s exercise (39.3±2.3 vs. 36.8±1.9 mL/min/kg, P<0.05. The total O2 consumed was significantly higher (P<0.05) during HTE (66.8±7.6 L) than during the 15s/15s (62.3±8.6 L). Blood lactate [La] after the first set of HTE was significantly higher than the 15s/15s (12.5±2.0 vs. 10.6±2.0 mmol/L, P<0.05). However, RPE provided by players suggested that the 15s/15s was more intense than the HTE (13±1.8 vs. 11.7±1.4, P<0.05).
  
  
  CONCLUSIONS
  Our results demonstrate that VO2 and [La] were higher during HTE than during the 15s/15s when matched with duration. However, HTE was perceived less intense than 15s/15s. Thus, the use of HTE appears as an effective alternative for fitness coaches to develop aerobic endurance in soccer players.
authors.affiliation: Movement, Sport and health Sciences Laboratory (M2S), Rennes 2 University - ENS Cachan, France.
authors.forename: Hassane
authors.initials: H
authors.lastname: Zouhal
authors.affiliation: Movement, Sport and health Sciences Laboratory (M2S), Rennes 2 University - ENS Cachan, France.
authors.forename: Emmeran
authors.initials: E
authors.lastname: Lemoal
authors.affiliation: Human Performance Laboratory, Technological and Higher Education Institute of Hong Kong, Hong Kong.
authors.forename: Del P
authors.initials: del P
authors.lastname: Wong
authors.affiliation: High Institute of Sport and Physical Education, Ksar-Saïd, Manouba University, Tunisia.
authors.forename: Omar
authors.initials: O
authors.lastname: Benounis
authors.affiliation: School of Sport and Exercise Sciences, University of Rome Tor Vergata, Rome, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Castagna
authors.affiliation: Movement, Sport and health Sciences Laboratory (M2S), Rennes 2 University - ENS Cachan, France.
authors.forename: Corentin
authors.initials: C
authors.lastname: Duluc
authors.affiliation: Rangers Football Club, Sports Science Department, Glasgow, Scotland, UK.
authors.forename: Adam L
authors.initials: AL
authors.lastname: Owen
authors.affiliation: Research Institute for Sport and Exercise Sciences, School of Human Sciences, Liverpool John Moores University, Liverpool, UK.
authors.forename: Barry
authors.initials: B
authors.lastname: Drust
keywords: Aerobic Fitness; Football; Interval-Training; Rating of Perceived Exertion