Effect of Endurance Training on Hemoglobin Mass and V-O 2max in Male Adolescent Athletes

Abstract

Purpose: It is unknown, whether endurance training stimulates hemoglobin mass (Hb mass ) and maximal oxygen uptake (V-O 2max ) increases during late adolescence. Therefore, this study assessed the influence of endurance training on Hb mass , blood volume parameters, and V-O 2max in endurance athletes and control subjects from age 16 to 19 yr. Methods: Hemoglobin mass, blood volume parameters, V-O 2max and anthropometric parameters were measured in male elite endurance athletes from age 16 to 19 yr in 6-month intervals (n = 10), as well as in age-matched male controls (n = 12). Results: Neither the level of Hb mass per lean body mass (LBM) (P = 0.80) nor the development of Hb mass during the 3 yr (P = 0.97) differed between athletes and controls. Hb mass at age 16 yr was 13.24 ± 0.89 g·kg -1 LBM and increased by 0.74 ± 0.58 g·kg -1 LBM (P < 0.01) from age 16 to 19 yr. There was a high correlation between Hb mass at age 16 and 19 yr (r = 0.77; P < 0.001). Plasma volume, blood volume, and V-O 2max were higher in athletes compared to controls (P < 0.05). Blood volume and V-O 2max increased with age (P < 0.01, similarly in both groups). Conclusions: Endurance training volumes do not explain individual differences in Hb mass levels nor Hb mass and V-O 2max development in the age period from 16 to 19 yr. The higher V-O 2max levels of athletes may be partially explained by training-induced higher plasma and blood volumes, as well as other training adaptations. Since Hb mass at age 16 yr varies substantially and the development of Hb mass in late adolescence is comparably small and not influenced by endurance training, Hb mass at age 16 yr is an important predictor for Hb mass at adult age and possibly for the aptitude for high-level endurance performance.