Purpose

To analyze the effect of a brief, 4-minute bout of high intensity interval exercise on the cellular and growth factor content of platelet-rich plasma

Methods and Materials

10 volunteers were recruited. 15mL of blood was harvested to create platelet-rich plasma (PRP) using the autologous conditioned plasma (ACP) system. Volunteers then performed 4 minutes of high intensity interval exercise (HIIE) on an exercise bike. After a brief recovery period, blood was re-drawn and a second PRP sample created.

Samples were analyzed for cellular content (platelets, leukocytes, red blood cells and mean platelet volume) and growth factor content (PDGF, VEGF, IGF and TGF).

Paired sample t-tests were used to determine mean differences. An a priori alpha level off 0.05 was used to determine significance. A post-hoc Bonferroni correction was applied to correct for family-wise error rate, changing the significance level to less than or equal to 0.006.

Results

Results

A significant difference in cell count between pre- and post-exercise PRP concentrations was noted only for platelet count. Mean platelet count was 367.4 ± 57.5 thousand per microliter at baseline and rose to 497.7 ± 93.3 thousand per microliter after the four minute exercise protocol. Mean values for the other three categories saw increases, but were not statistically significant.

A significant difference in growth factor count between pre- and post-exercise PRP concentrations was noted only for TGF. Mean TGF concentration was 8237.2 ± 7676.5 pg/mL at baseline and rose to 21535.7 ± 4062.6 pg/mL after the four minute exercise protocol. Mean values for the other three growth factors all saw increases, but none were statistically significant.

Conclusion

A brief, 4 minute bout of high intensity interval exercise increases the platelet and TGF content of PRP. Further clinical research is needed to determine if these increases result in superior clinical outcomes.