5 Key Takeaways

• 1

  This systematic review and meta-analysis included 11 longitudinal observational studies involving 508 athletes across 6 sports cohorts and 1 military cohort.

• 2

  Across all studies, higher inertial-sensor-derived training loads were associated with musculoskeletal injury, but the pooled estimate of 2.74 was exploratory.

• 3

  Cumulative load magnitude was associated with injury in 5 studies, with a pooled effect estimate of 2.86 and no detected statistical heterogeneity.

• 4

  Evidence for acute-to-chronic workload ratio was equivocal: its pooled estimate was 2.64, heterogeneity was substantial, and the association was not significant under the primary inference method.

• 5

  All outcomes were rated very low certainty, and the evidence did not establish injury prediction, prevention through load modification, or specific training-load thresholds.