The Association Between Training Load and Performance in Team Sports: A Systematic Review

BackgroundAdequate training loads promote favorable physical and physiological adaptations, reduce the likelihood of illness and injury, and, therefore, increase the possibility of success during competition.ObjectivesOur objective was to systematically examine the association between training load and performance outcomes in team sports.MethodsWe systematically searched the PubMed, SPORTDiscus, and PsycINFO databases for original research published before July 2018. The search included terms relevant to training load, performance, and team sports. Articles were screened using pre-defined selection criteria, and methodological quality was assessed independently by two authors before data were extracted by the lead author.ResultsThe electronic search yielded 5848 articles, 2373 of which were duplicates. A further 17 articles were retrieved from additional sources. In total, 26 articles met the inclusion criteria for this review, with quality scores ranging from 6 to 10 out of 11. Training exposure was more strongly associated with aerobic performance than other external training load measures. High-intensity activity (90% of maximum heart rate) was strongly associated with aerobic performance. The individualized training impulse model was strongly associated with aerobic performance, whereas various other training impulse models and perceptual training load measures showed weak associations with aerobic performance. There were no clear associations between training load and neuromuscular variables or game-related statistics.ConclusionWe found no consistent associations between external training load measures and performance. High-intensity internal training load appears to be the most prominent indicator of aerobic performance.