This study tested the hypothesis that autologous blood transfusion (ABT) of ~50% of the red blood cells (RBCs) from a standard 450 ml phlebotomy would increase mean power in a cycling time trial. Additionally, the study investigated whether further ABT of RBCs obtained from another 450 ml phlebotomy would increase repeated cycling sprint ability.
In a randomized, double-blind, placebo-controlled crossover design (3-month wash-out), nine highly trained male subjects donated two 450 ml blood bags each (BT-trial) or were sham phlebotomized (PLA-trial). Four weeks later, a 650 kcal time trial (n=7) was performed three days before and 2 h after receiving either ~50% (135 ml) of the RBCs or a sham transfusion. On the following day, transfusion of RBCs (235 ml) from the second donation or sham transfusion was completed. A 4×30 s all-out cycling sprint interspersed by 4 min of recovery was performed six days before and three days after the second ABT (n=9).
The mean power was increased in time trials from before to after transfusion (P<0.05) in BT (213±35 vs. 223±38 W; mean±SD) but not in PLA (223±42 vs. 224±46 W). In contrast, the mean power output across the four 30 s sprint bouts remained similar in BT (639±35 vs. 644±26 W) and PLA (638±43 vs. 639±25 W).
ABT of only ~135 ml of RBCs is sufficient to increase mean power in a 650 kcal cycling time trial by ~5% in highly trained men. In contrast, a combined high-volume transfusion of ~135 and ~235 ml of RBCs does not alter 4×30 s all-out cycling performance interspersed with 4 min of recovery.
1Department of Nutrition, Exercise and Sports (NEXS), University of Copenhagen, Denmark;
2Section for Transfusion Medicine and
3Department of Anesthesiology, The Copenhagen Muscle Research Center, Rigshospitalet, University of Copenhagen, Denmark
Correspondence: Nikolai Baastrup Nordsborg, Department of Nutrition, Exercise and Sports (NEXS), Faculty of Science, University of Copenhagen. email@example.com. Tel.: +45 35321612. Fax: +45 35320870
Jacob Bejder was in part funded by Partnership for Clean Competition and Anti-Doping Denmark.
CONFLICT OF INTEREST: The authors have no conflict of interest. The results of the present study do not constitute endorsement by the American College of Sports Medicine. The results of the study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation.
Accepted for publication October 2018.