Iron's True Weight: Does the Amount of Iron in the Body Equate to the Amount of Iron on the Bar in Australian Football League Women's Players?

BACKGROUND: The physiological requirements of a successful team sport performance partly depend on iron-facilitated mechanisms. However, how low iron stores affect team sport athletes remains unclear.

PURPOSE: To explore the influence of iron status on strength and power performance in elite female Australian Rules Football players.

METHODS: Iron indices were measured in 30 players (age 23 ± 4 y; body mass 70 ± 6 kg) at the start and end of the 10-week preseason. Players were categorized as iron deficient (ID; serum ferritin (sFer) < 40 µg/L) or iron sufficient (sFer > 40 µg/L). Over this period, three-repetition maximum and sport-specific performance measures were evaluated.

RESULTS: Approximately 80% of all the sFer samples primarily ranged between 9 and 60 µg/L. Strength (e.g., squat, bench press) was up to 13% lower in ID players in week 1, with no substantial differences between groups during week 10. There were marginal differences (ID: -1% to +3%) in performance for all the remaining measures between groups (e.g., 10-m sprint). Very weak to moderate correlations were observed between all the performance measures and fixed effects (e.g., sFer, other strength assessments), increasing to moderate to very strong correlations when accounting for random effects (athlete).

CONCLUSIONS: Iron deficiency may compromise strength performance, but this shortcoming may not translate to measures of power and speed. Individualized iron monitoring practices for athlete health and performance are encouraged.