title: The optimal exercise to rest ratios in repeated sprint ability training in youth soccer players.
abstract: BACKGROUND
  The aim of this study was to investigate the applicability of three different exercise to rest ratios in RSA training in youth soccer players, applying those ones already adopted in adult players, when performing three different sprinting modes (straight, shuttle and sprinting with changing of direction).
  
  
  METHODS
  Eighteen young trained male soccer players (Height: 1.66±0.07 m; weight: 58.22±7.64 kg; BMI 19.37±3.42 kg·m-2; age:14 years) participated to the study. In order to compare the different values of the time recorded, a Fatigue Index (FI) was used. Recovery times among trials in the sets were administered according to the 1:5, 1:3; 1:2 exercise to rest ratio, respectively.
  
  
  RESULTS
  Significant differences among trials within each set (Repeated Measures Anova; P<0.05) were found. as evidence of fatigue over time. with an average decay of performance of about 4%, but no significant differences were found in FI%, among the three different sprinting modalities when applying the investigated exercise to rest ratios (Factorial Anova; between; P>0.05).
  
  
  CONCLUSIONS
  The results of this study confirm that the exercise to rest ratios considered in this study might be suitable to design effective testing protocols and training sessions aimed at the development of the RSA in youth soccer players, keeping the performances in the speed domain (FI%< ≈7-8%) but inducing the fatigue processes sought with this kind of training method.
authors.affiliation: Faculty of Medicine and Surgery, School of Sports and Exercise Sciences, Tor Vergata University, Rome, Italy - bruno.ruscello@uniroma2.it; School of Sports and Exercise Sciences, San Raffaele University, Rome, Italy; Federazione Italiana Hockey, Rome, Italy; Sport 3.0 Foundation, Bologna, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Ruscello
authors.affiliation: Faculty of Medicine and Surgery, School of Sports and Exercise Sciences, Tor Vergata University, Rome, Italy.|Faculty of Medicine and Surgery, Doctoral School of Advanced Sciences and Technologies in Reabilitation Medicine and Sports, University of Rome &quot;Tor Vergata&quot;, Rome, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Partipilo
authors.affiliation: Faculty of Medicine and Surgery, School of Sports and Exercise Sciences, Tor Vergata University, Rome, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Pantanella
authors.affiliation: Faculty of Medicine and Surgery, School of Sports and Exercise Sciences, Tor Vergata University, Rome, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Esposito
authors.affiliation: Faculty of Medicine and Surgery, School of Sports and Exercise Sciences, Tor Vergata University, Rome, Italy.|School of Sports and Exercise Sciences, San Raffaele University, Rome, Italy.|Federazione Italiana Giuoco Calcio, Rome, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: D'Ottavio
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D054874:Athletic Performance / Q000502:physiology*; D015444:Exercise; D005080:Exercise Test; D005221:Fatigue; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology; D005082:Physical Exertion / Q000502:physiology; D012146:Rest / Q000502:physiology*; D012420:Running / Q000502:physiology*; D012916:Soccer / Q000502:physiology*; D013997:Time Factors