Comparing Total Hemoglobin Mass Between Selected NCAA Division I Athletes And Recreationally Active Students

Abstract

Total hemoglobin mass (tHb) is linearly related to total body mass, however, whether this relationship is altered by lean tissue mass, training or sex remains controversial. PURPOSE: To investigate if lean mass is a more appropriate determinant of tHb compared to body mass across NCAA DI athletes and controls. We will also determine if this relationship is altered by sex and/or training status. METHODS: Nordic (6F & 6M) and alpine (5M) skiers, football players (7M) and recreationally active student controls (9F & 10M) from the University of Colorado Boulder participated. The optimized carbon monoxide rebreathing procedure was used to determine tHb. Body composition was determined via DXA. Since female athletes were not present in all groups, statistical analyses were performed for males across all groups and a separate comparison was made between female nordic skiers and control groups. RESULTS: The overall correlations of tHb with body mass or lean tissue mass were significant (R2 = 0.73 & R2 = 0.88), but the positive relationship was stronger when using lean mass (p<0.001). For males, body mass and lean tissue mass were greater in football with no significant differences between any other group. Football had a greater tHb compared to control and alpine (1168.7 ± 126.9 vs. 925.9 ± 123.0 & 936.8 ± 151.9 g), but was not different than nordic (1052.5 ± 166.7 g). Nordic tHb was greater than control, but not different from alpine. When tHb was normalized using body mass and lean mass, nordic (14.5 ± 1.5 & 16.5 ± 1.2 g/kg) was greater than football (10.4 ± 0.9 & 14.4 ± 1.5 g/kg), alpine (11.6 ± 1.1 & 14.2 ± 0.6 g/kg) and control (11.8 ± 0.6 & 14.6 ± 0.8 g/kg) groups while no differences between any other groups were found. For females, body mass, lean tissue mass and tHB (656.4 ± 72.9 vs. 566.1 ± 66.0 g) were not different between nordic and control. When tHb was normalized using body mass, nordic (11.3 ± 0.7 g/kg) was greater than control (9.5 ± 1.0 g/kg), but when tHB was normalized using lean mass there was no difference (14.5 ± 1.1 vs. 13.8 ± 1.4 g/kg). CONCLUSION: Lean tissue mass explains a greater amount of variability in tHB compared to total body mass. In males, to examine the effect of endurance training on tHb, it is more appropriate to normalize by lean mass. Additional research is needed when comparing the effects of endurance training between female groups.