Maintenance of iron status in healthy men during an extended period of stress and physical activity.
Body weight loss and iron status of 55 male soldiers were measured during 62 d of intense physical activity and sustained stress and sleep deprivation. Body weight declined from (mean +/- SD) 75.9 +/- 9.0 to 63.8 +/- 6.7 kg (P < 0.05). Serum iron fell from 13.7 +/- 5.6 to 8.3 +/- 3.6 mumol/L by 14 d (P < 0.05), but returned to baseline values by 8 wk. Total iron-binding capacity declined from 53.4 +/- 6.8 at baseline to 47.5 +/- 6.3 mumol/L at 8 wk (P < 0.05). During the study, hematocrit, serum hemoglobin, and erythrocyte count did not change, whereas ferritin increased from 116 +/- 84 to 202 +/- 106 micrograms/L (P > 0.05). Adequate dietary iron, initiation of training with adequate body iron stores, and physical activity not in excess of pretraining workloads contributed to the maintenance of iron status during prolonged physical activity and stress. Our results suggest that some acute phase-like disturbances in iron metabolism may be a normal component of adaptation to stress and physical activity in healthy men.
Moore
R J
RJ
US Army Research Institute of Environmental Medicine, Natick, MA 01760-5007.
Friedl
K E
KE
Tulley
R T
RT
Askew
E W
EW
D000328:Adult; D005293:Ferritins / Q000097:blood; D006801:Humans; D007501:Iron / Q000097:blood*; D008297:Male; D008889:Military Personnel; D010806:Physical Education and Training; D010809:Physical Fitness; D012892:Sleep Deprivation / Q000502:physiology; D013315:Stress, Psychological / Q000097:blood*; D015431:Weight Loss
D005293:Ferritins; D007501:Iron