Effect of Various Modes of Exercise on the Mobilization of Stem Cells

Abstract

The purpose of this descriptive pilot study was to determine the temporal nature of peripheral stem cells in response to various modes of exercise. Six individuals (ages 21–54 years) were enrolled. The study protocol required a stem cell assessment following three exercise conditions: aerobic, concentric resistance and resistance exercise. Peripheral blood was collected prior to the exercise regimen and at five time points following completion of the prescribed exercise regimen. The peripheral blood was analyzed flow cytometrically for mesenchymal stem cells (MSC) (CD45lo/Stro1+), endothelial stem cells (ESC) (CD34−/31+/34+) and hematopoietic stem cells HSC) (CD45+/34hi). The results of the study did not demonstrate any significant correlations with respect to mobilization of MSC, ESC or HSC with any of the exercise modalities over time. However, HSC's did show more dramatic changes to concentric and eccentric exercises than MSC or endothelial stem cells, increasing as much as 4 fold following exercise. This is in contrast to aerobic exercise in which a small and inconsistent response of HSC's post exercise was seen. Overall, no change in any stem cell type was seen after a 30 minute bout of moderate aerobic exercise. Thus, resistance type exercise appeared to elicit more dramatic changes in circulating stem cell number than aerobic exercise. Also, the response of the HSCs to resistance exercise was more consistent than that of MSC or endothelial cells. It is possible that the inconsistent response of MSC and endothelial cells reflects the variable training status of the subjects relative to resistance training or the normal variance in stem cell physiology. These questions will be addressed in future studies.