Effect of Exercise-Induced Hyperthermia on Serum Iron Concentration

Serum iron levels have been shown to decline both with fever and with strenuous exercise, leading to the supposition that the decrease might be the result of a rise in core body temperature. To evaluate this hypothesis, the serum iron response to an exercise-induced 1.5 degrees C rise in core body temperature was measured. To increase core temperature, five females and two males exercised in an environmental chamber heated to 41 degrees C with a relative humidity of 40%. Blood samples were taken before exercise and immediately after body temperature increased approximately 1.5 degrees C. Blood was also collected 1 h, 6 h, and 24 h postexercise. Results showed that the core body temperature significantly increased (p