title: Physiological response, time-motion characteristics, and reproducibility of various speed-endurance drills in elite youth soccer players: small-sided games versus generic running.
abstract: OBJECTIVE
  To quantify the physiological responses, time-motion characteristics, and reproducibility of various speed-endurance-production (SEP) and speed-endurance-maintenance (SEM) drills.
  
  
  METHODS
  Sixteen elite male youth soccer players completed 4 drills: SEP 1 v 1 small-sided game (SSG), SEP running drill, SEM 2 v 2 SSG, and SEM running drill. Heart-rate response, blood lactate concentration, subjective rating of perceived exertion (RPE), and time-motion characteristics were recorded for each drill.
  
  
  RESULTS
  The SEP and SEM running drills elicited greater (P < .05) heart-rate responses, blood lactate concentrations, and RPE than the respective SSGs (ES 1.1-1.4 and 1.0-3.2). Players covered less (P < .01) total distance and high-intensity distance in the SEP and SEM SSGs than in the respective running drills (ES 6.0-22.1 and 3.0-18.4). Greater distances (P < .01) were covered in high to maximum acceleration/deceleration bands during the SEP and SEM SSGs than the respective running drills (ES 2.6-4.6 and 2.3-4.8). The SEP SSG and generic running protocols produced greater (P < .05) blood lactate concentrations than the respective SEM protocols (ES 1.2-1.7). Small to moderate test-retest variability was observed for heart-rate response (CV 0.9-1.9%), RPE (CV 2.9-5.7%), and blood lactate concentration (CV 9.9-14.4%); moderate to large test-retest variability was observed for high-intensity-running parameters (CV > 11.3%) and the majority of accelerations/deceleration distances (CV > 9.8%) for each drill.
  
  
  CONCLUSIONS
  The data demonstrate the potential to tax the anaerobic energy system to different extents using speed-endurance SSGs and that SSGs elicit greater acceleration/ deceleration load than generic running drills.
authors: Medical Dept, Newcastle United Football Club, Newcastle, UK.
authors: Jack D
authors: JD
authors: Ade
authors: Jamie A
authors: JA
authors: Harley
authors: Paul S
authors: PS
authors: Bradley
mesh_terms: D000054:Acceleration; D000293:Adolescent; D000367:Age Factors; D015415:Biomarkers / Q000097:blood; D003654:Deceleration; D006339:Heart Rate; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D009048:Motor Skills; D010465:Perception; D064797:Physical Conditioning, Human / Q000379:methods*; D010807:Physical Endurance; D005082:Physical Exertion; D015203:Reproducibility of Results; D012420:Running; D012916:Soccer; D013997:Time Factors; D013996:Time and Motion Studies
chemical_list: D015415:Biomarkers; D019344:Lactic Acid