Changes in haemoglobin and ferritin levels during basic combat training: relevance for attrition and injury frequency

IntroductionThe primary aim of the present study was to assess interindividual and intraindividual variations in haemoglobin and ferritin concentrations in Swedish recruits over 5 months of basic combat training (BCT). The secondary aim was to find predictors for missing training (a precursor for attrition) and overuse injuries during BCT.MethodsIn a cohort design, a total of 58 female and 104 male recruits provided complete data. We assessed the ferritin concentrations and haemoglobin concentrations at baseline and after 5 months of BCT and physical work capacity at baseline.ResultsDuring BCT, haemoglobin concentrations increased significantly in both females and males. Ferritin concentrations decreased significantly in both sexes and the prevalence of iron deficiency (ID) (ie, ferritin levels