Haematological parameters decrease following one unit of whole blood donation which results in a detrimental effect on cardiorespiratory fitness and maximal exercise capacity. However, it remains unclear to what extent blood donation will impact exercise performance across varying levels of cardiorespiratory fitness. The aim of this study is to compare the effects of a standard blood donation on maximal exercise performance performed 24 h post-blood donation in individuals with varying levels of cardiorespiratory fitness. Methods: Forty-two males (mean age 22 ± 2.1 years) were recruited and segregated into Low, Moderate and Superior fitness groups. Subjects performed a multi-stage shuttle run test on the day prior to a standard blood donation procedure, and subsequently 24 h post-blood donation. Blood samples were taken on both test days and analysed for haematological parameters. Results: Exercise performance, represented by predicted VO2max were 0.6%, 1.0% and 4.1% lower in the Low, Moderate and Superior fitness groups respectively. However, the magnitude of reduction was only statistically significant in the Superior fitness group (p = 0.017). Compared to baseline, all fitness groups demonstrated significant reductions in haematocrit (Low: -8.4%, Moderate: -9.1%, Superior: -7.2%) and haemoglobin (Low: -7.6%, Moderate: -7.8%, Superior: -5.5%) levels at 24 h post-blood donation. Spearman correlation analysis revealed that changes in haemoglobin concentrations were not associated with changes in exercise performance in all groups. Conclusion: Exercise performance was only significantly reduced in the Superior fitness group. Well-trained individuals should be refrained from blood donation just prior to competitions.
Exercise has been suggested as the best and the most affordable way for managing blood pressure. The insertion/ deletion of angiotensin I-converting enzyme (ACE) I/D gene polymorphism had been reported to be linked with sev- eral diseases such as hypertension and diabetic nephropathy. Several studies showed that blood pressure response to exercise training for health management also vary among individuals with different genotypes of ACE I/D gene poly- morphism. A study of 9 months of endurance exercise training at 75 to 85 % of VO2max showed that the decrease of resting blood pressure in I allele carriers wass greater than D allele carriers. In contrast, other study discovered that adult women with D allele had greater reduction in resting blood pressure than those with I allele, following a 12-week combined aerobic and resistance exercise training. Despite the inconsistencies of some findings, it has remained unknown if the ACE I/D gene polymorphism would also influence blood pressure response to isometric handgrip training that had been found to be superior to the dynamic resistance exercise training in controlling and preventing high blood pressure. Thus, this article was to review the literature on ACE I/D gene polymorphism and blood pressure response to exercise training that could serve as the basis for future research to identify individuals who will lower resting blood pressure the most with exercise training program for health management.