title: Training-Load-Guided vs Standardized Endurance Training in Recreational Runners.
abstract: OBJECTIVE
  To compare the effects of a standardized endurance-training program with individualized endurance training modified based on the cumulative training load provided by the Polar training-load feature.
  
  
  METHODS
  After 12 wk of similar training, 24 recreationally endurance-trained men were matched to a training-load-guided (TL, n = 10) or standardized (ST, n = 14) group and continued training for 12 wk. In TL, training sessions were individually chosen daily based on an estimated cumulative training load, whereas in ST the training was standardized with 4-6 sessions/wk. Endurance performance (shortest 1000-m running time during an incremental field test of 6 × 1000 m) and heart-rate variability (HRV) were measured every 4 wk, and maximal oxygen consumption (VO2max) was measured during an incremental treadmill test every 12 wk.
  
  
  RESULTS
  During weeks 1-12, similar changes in VO2max and 1000-m time were observed in TL (+7% ± 4%, P = .004 and -6% ± 4%, P = .069) and ST (+5% ± 7%, P = .019 and -8% ± 5%, P < .001). During wk 13-24, VO2max statistically increased in ST only (3% ± 4%, P = .034). The 1000-m time decreased in TL during wk 13-24 (-9% ± 5%, P = .011), but in ST only during wk 13-20 (-3% ± 2%, P = .003). The overall changes in VO2max and 1000-m time during wk 0-24 were similar in TL (+7% ± 4%, P = .001 and -9% ± 5%, P = .011) and ST (+10% ± 7%, P < .001 and -13% ± 5%, P < .001). No between-groups differences in total training volume and frequency were observed. HRV remained statistically unaltered in both groups.
  
  
  CONCLUSIONS
  The main finding was that training performed according to the cumulative training load led to improvements in endurance performance similar to those with standardized endurance training in recreational endurance runners.
authors.forename: Moritz
authors.initials: M
authors.lastname: Schumann
authors.forename: Javier
authors.initials: J
authors.lastname: Botella
authors.forename: Laura
authors.initials: L
authors.lastname: Karavirta
authors.forename: Keijo
authors.initials: K
authors.lastname: Häkkinen
mesh_terms: D000328:Adult; D005080:Exercise Test; D006339:Heart Rate; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D010101:Oxygen Consumption; D010807:Physical Endurance / Q000502:physiology*; D055070:Resistance Training / Q000379:methods*; D012420:Running / Q000502:physiology*
chemical_list: D019344:Lactic Acid
keywords: cumulative training load; heart-rate variability; individualized training