Impaired skeletal muscle oxygenation following allogeneic hematopoietic stem cell transplantation is associated with exercise capacity.

<bold>Introduction: </bold>Impaired skeletal muscle oxygenation potentially contributes to reduced exercise capacity in allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients during early recovery and may explain altered hemoglobin responses to exercise following allo-HSCT. We investigated whether skeletal muscle oxygenation parameters and hemoglobin parameters in the tibialis anterior decreased following allo-HSCT, and whether these results were associated with declines in exercise capacity.<bold>Methods: </bold>We used near-infrared spectroscopy during and following a repeated isometric contraction task at 50% of maximal voluntary contraction in 18 patients before and after allo-HSCT.<bold>Results: </bold>The rate of decrease in the muscle oxy-hemoglobin saturation (SmO2; an index of skeletal muscle oxygenation) was significantly lower after allo-HSCT (P < 0.01). In contrast, total hemoglobin (an index of hemoglobin) was not different after allo-HSCT. Furthermore, SmO2 during and following exercise was associated with exercise capacity (r = 0.648; P = 0.004 vs. r = 0.632; P = 0.005).<bold>Conclusion: </bold>The results of this study reveal that although the peripheral hemoglobin response was not altered by allo-HSCT, skeletal muscle oxygenation was decreased following allo-HSCT. Furthermore, the decrease in skeletal muscle oxygenation was associated with a reduction in exercise capacity. [ABSTRACT FROM AUTHOR]