Erythropoiesis with endurance training: dynamics and mechanisms

Am J Physiol Regul Integr Comp Physiol. 2017 Jun 1;312(6):R894-R902. doi: 10.1152/ajpregu.00012.2017. Epub 2017 Apr 5.

Abstract

The purpose of the present study was to characterize the progression of red blood cell volume (RBCV) expansion and potential volumetric and endocrine regulators of erythropoiesis during endurance training (ET). Nine healthy, untrained volunteers (age = 27 ± 4 yr) underwent supervised ET consisting of 3-4 × 60 min cycle ergometry sessions per week for 8 wk. Plasma volume (PV), RBCV, and overnight fasting hematological markers were determined before and at weeks 2, 4, and 8 of ET. In addition, plasma erythropoietin (EPO), cortisol, copeptin, and proatrial natriuretic peptide concentrations were measured during a 3-h morning period at baseline and postexercise at weeks 1 and 8 PV increased from baseline (2,405 ± 335 ml) at weeks 2, 4, and 8 (+374 ± 194, +505 ± 156, and +341 ± 160 ml, respectively, P < 0.001). Increases in RBCV from baseline (1,737 ± 442 ml) were manifested at week 4 (+109 ± 114 ml, P = 0.030) and week 8 (+205 ± 109 ml, P = 0.001). Overnight fasting plasma EPO concentration increased from baseline (11.3 ± 4.8 mIU/ml) at week 2 (+2.5 ± 2.8 mIU·ml-1, P = 0.027) and returned to baseline concentration at weeks 4 and 8 Higher 3-h-postexercise EPO concentration was observed at week 1 (11.6 mIU/ml) compared with week 8 (8.4 ± 3.9 mIU/ml, P = 0.009) and baseline (9.0 ± 4.2 mIU/ml, P = 0.019). Linear relationships between EPO concentration and hematocrit (β = -56.2, P < 0.001) and cortisol (β = 0.037, P < 0.001) were detected throughout the ET intervention. In conclusion, ET leads to mild, transient increases in circulating EPO concentration, concurring with early PV expansion and lowered hematocrit, preceding gradual RBCV enhancement.

Keywords: erythropoietin; exercise training; plasma volume; red blood cell volume.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Atrial Natriuretic Factor / blood
  • Bicycling
  • Body Composition
  • Erythrocyte Count
  • Erythrocytes / metabolism
  • Erythrocytes / physiology*
  • Erythropoiesis*
  • Erythropoietin / metabolism
  • Exercise / physiology*
  • Exercise Tolerance
  • Female
  • Glycopeptides / blood
  • Hematocrit
  • Hemodynamics
  • Humans
  • Hydrocortisone / blood
  • Male
  • Physical Endurance*
  • Plasma Volume
  • Time Factors
  • Young Adult

Substances

  • EPO protein, human
  • Glycopeptides
  • copeptins
  • Erythropoietin
  • Atrial Natriuretic Factor
  • Hydrocortisone