Iron status and predicted VO 2 max in Indian adolescents

The objective of this study was to determine whether iron status has a negative impact on predicted maximum oxygen consumption (VO 2 max, ml·kg −1 ·min −1 ) in Indian adolescents. School children (N=81 males, 74 females; age=12–16 y) were screened for indicators of iron status with a venous blood sample to assess ferritin (sFer), transferrin receptor (sTfR), hemoglobin (Hb), alpha‐1 acid glycoprotein (AGP), and C‐reactive protein (CRP) in rural Maharashtra, India. Anemia (N=10M, 15F) was defined as Hb<12.0g/dL; iron‐depletion (N=17M, 21F) was defined as sFer<16.0ng/mL. Each subject wore a Polar heart rate monitor and CosMed K4b 2 indirect calorimeter while performing a YMCA sub‐maximal test on a Monark 874E cycle ergometer. VO 2 max was predicted by extrapolating the relationship between VO 2 and heart rate to predicted maximum heart rate (195 bpm). Anemic boys had a significantly lower predicted VO 2 max (41.2ml·kg −1 ·min −1 ) than non‐anemic boys (45.9ml·kg −1 ·min −1 ) (p<0.05). Iron depleted (ID) boys had a significantly lower predicted VO 2 max (42.0ml·kg −1 ·min −1 ) than non‐ID boys (46.2ml·kg −1 ·min −1 ) (p<0.05). There were no significant differences in predicted VO 2 max between anemic and non‐anemic females (34.6ml·kg −1 ·min − 1 ,36.7ml·kg −1 ·min −1 , respectively) or ID and non‐ID females (36.1ml·kg −1 ·min −1 , 36.4ml·kg −1 ·min −1 , respectively). Supported by HarvestPlus.Grant Funding Source : HarvestPlus