Quantifying Workload and Injury Risk Among Cricket Fast Bowlers: A Systematic Review and Meta-Analysis

Bowling workload is a well-recognised contributor to gradual-onset injuries in cricket fast bowlers; however, considerable variability exists in how workload is defined, quantified, and interpreted across studies. Although the acute:chronic workload ratio (ACWR) is widely applied in cricket research, its use remains debated regarding its predictive validity, mathematical limitations, and inconsistent methodological application. This systematic review aimed to synthesise existing evidence on workload quantification and workload-injury associations in cricket fast bowlers and to evaluate acute-chronic workload exposure using a restricted meta-analytic approach. A comprehensive search of MEDLINE, Embase, SPORTDiscus, CINAHL, Scopus, Web of Science, PubMed, and Google Scholar was conducted, spanning 2000 to 2024. Boolean search combinations included terms such as "cricket," "fast bowler," "workload," "bowling load," "acute:chronic workload ratio," "injury," and "injury risk." Study screening was performed using Rayyan (Rayyan Systems Inc., Cambridge, MA, USA) following duplicate removal in Mendeley (Elsevier B.V., Amsterdam, Netherlands), and eligible studies were independently assessed by three reviewers. Thirty-three studies met the inclusion criteria and were synthesised narratively, while six prospective cohort studies reporting acute-chronic workload exposure with extractable effect estimates were included in a random-effects meta-analysis. The included studies involved elite, sub-elite, and junior male and female fast bowlers and employed diverse workload monitoring methods, including manual tracking, wearable technology, subjective measures, and biomechanical assessments. Across studies, high acute workloads, rapid workload escalations, and inadequate recovery were consistently associated with increased injury risk, particularly involving the lumbar spine. These associations were broadly consistent across competitive levels, although elite cohorts demonstrated more robust monitoring protocols and junior populations exhibited greater vulnerability during rapid load escalation. Elevated ACWR values, typically ranging from approximately 1.4 to 2.0 and above, were associated with higher injury incidence, whereas greater chronic workload exposure appeared protective. Meta-analysis demonstrated a significant association between elevated acute-chronic workload exposure and injury risk (RR = 2.45; 95% CI: 1.48-4.06), although substantial heterogeneity was observed (I2 ≈ 77%), likely attributable to variability in workload metrics, inconsistency in injury definitions, and differences in study populations. These findings indicate that acute workload spikes relative to recent chronic workload are consistently linked to increased injury risk in cricket fast bowlers; however, heterogeneity and study-level bias limit definitive causal inference. Consequently, workload monitoring strategies should emphasise progressive load development, adequate recovery, and individualised interpretation rather than reliance on rigid threshold values. Notably, evidence specific to Indian fast bowlers remains limited, underscoring a critical gap for future research.