Effect of Repeated Whole Blood Donations on Aerobic Capacity and Hemoglobin Mass in Moderately Trained Male Subjects: A Randomized Controlled Trial

Abstract

BackgroundThe aims of the present study were to investigate the impact of three whole blood donations on endurance capacity and hematological parameters and to determine the duration to fully recover initial endurance capacity and hematological parameters after each donation.MethodsTwenty-four moderately trained subjects were randomly divided in a donation (n = 16) and a placebo (n = 8) group. Each of the three donations was interspersed by 3 months, and the recovery of endurance capacity and hematological parameters was monitored up to 1 month after donation.ResultsMaximal power output, peak oxygen consumption, and hemoglobin mass decreased (p < 0.001) up to 4 weeks after a single blood donation with a maximal decrease of 4, 10, and 7%, respectively. Hematocrit, hemoglobin concentration, ferritin, and red blood cell count (RBC), all key hematological parameters for oxygen transport, were lowered by a single donation (p < 0.001) and cumulatively further affected by the repetition of the donations (p < 0.001). The maximal decrease after a blood donation was 11% for hematocrit, 10% for hemoglobin concentration, 50% for ferritin, and 12% for RBC (p < 0.001). Maximal power output cumulatively increased in the placebo group as the maximal exercise tests were repeated (p < 0.001), which indicates positive training adaptations. This increase in maximal power output over the whole duration of the study was not observed in the donation group.ConclusionsMaximal, but not submaximal, endurance capacity was altered after blood donation in moderately trained people and the expected increase in capacity after multiple maximal exercise tests was not present when repeating whole blood donations.Electronic supplementary materialThe online version of this article (doi:10.1186/s40798-016-0067-7) contains supplementary material, which is available to authorized users.

The acute effects of whole blood donation on cardiorespiratory and haematological factors in exercise: A systematic review

“…All 8 studies included were experimental in nature, incorporating a before and after blood donation approach, with only the Meurrens, et al [20] study using a control (sham bleed) group. Participant numbers ranged from 9–24 (13.5 ± 4.9) and hence appeared low, unfortunately only two studies, that of Judd, et al [31] and Meurrens, et al [20] provided power calculations to reflect sample size, although justification for sample size was presented in all studies except Krip, et al [32].…”

“…Research papers have historically determined that BD decreases [15,16,19,20] However, in this analysis the confidence intervals have not produced statistical significance. Individual studies have too much variance and therefore the pooled data using the Cohen’s d allows for comparisons across all papers.…”

“…Indeed, this systematic review had the potential to include 20 papers, but due to quality issues, only 9 papers were considered to be of good quality, none of the papers were considered to be excellent quality, based on the adapted scoring method [26]. Reasons for exclusion were heterogeneous, but a reoccurring theme even in the good quality papers was lack of a power calculation, indeed only the Meurrens, et al [20] and Judd, et al [31] studies that were in the list examined provided this.…”

“…The biological responses to acute BD are well documented, indeed early work from Karpovich and Millman [7] highlighted that a Hb decrement affected athletic performance, while later work from Balke and colleagues [15] proposed that from a BD of 500 ml there was a 9% decline in maximal oxygen uptake () and more recently Gordon and contemporaries [16] showed a 4.65% fall in from a 450 ml donation. Additionally associated markers of aerobic fitness have been shown to be altered following BD such as maximum aerobic power output (W max ) [17] and time to exhaustion (T Ex ) [18,19,20]. There is little doubt that decreasing blood volume via BD will diminish oxygen carrying capacity, as haemoglobin (Hb) concentration will have been reduced and it is the primary source for the conveyance of oxygen.…”

The deferred donor

“…The study indicated that haematological parameters are cumulatively affected upon repeated donations. Furthermore, the positive training effect observed in the placebo group was absent in the donation group , the latter exemplifying the benefit of a placebo group. A Cochrane review found 30 randomized trials of iron supplementation in blood donors and concluded that iron supplementation effectively increased haemoglobin levels and iron stores and reduced donor deferral for low haemoglobin levels.…”