BIOCHEMICAL MARKERS OF NUTRITION IN ELITE-MARATHON RUNNERS

Although diet surveys have been made in marathon runners, as far as we know their nutritional state has not been evaluated by measurement of the so-called biological markers of nutrition, such as transferrin, r etinol-binding protein, and prealbumin. We measured the levels of thes e substances in 18 marathon runners (11 men and 7 women; mean age 26.9 +/-4.0 years) and in 22 controls (13 men and 9 women; mean age 26.2+/- 3.6 years), As some of these markers are zinc-dependent, serum zinc le vels also were measured, Likewise. serum calcium, phosphorus, and magn esium levels were measured to ascertain the athletes' mineral status, Calcium corrected for proteins, phosphorus, magnesium, and zinc did no t differ between the marathon runners and controls; likewise, there we re no differences in serum ferritin and glucose levels, As regards the biological markers of nutrition, prealbumin levels were higher in ath letes than in controls (31.7+/-4.7 vs 28.9+/-4.8 mg/dl, p<0.025). Ther e were no differences in the levels of retinol-binding protein and tra nsferrin between runners and controls.