Conditioning participants to a relative pressure: Implications for practical blood flow restriction

Objective: To develop a valid method of applying blood flow restriction when the pressure cannot be known. This method involves conditioning the individual to what the goal pressure should be, such that the participant is able to recognize the sensation associated with that specific pressure. Approach: Participants were conditioned to 40% of their arterial occlusion pressure (AOP) by oscillating between pressures that were too high (60%) and pressures that were too low (20%). Incorrect pressures were used to highlight pressure sensations surrounding the correct pressure that participants would be asked to later identify. Participants made attempts to estimate pressures at 5 min and 24 h following the conditioning stimulus. Main results: A total of 40 participants completed this study. Estimated pressures at 5 min post conditioning were similar to the target pressure (-2 (-7, 3) mmHg; probability of H0: 0.675). However, pressures at 24 h post conditioning were underestimated as compared to the target pressure (-7 (-13,-2) mmHg). Additionally, pressures at 24 h appeared to be less than that at 5 min (-4.7 (-8.6, 0.9) mmHg; probability of H1: 0.84). The average absolute error was 11.2 mmHg (7.4% AOP) for 5 min and 14.0 mmHg (9.2% AOP) at 24 h. Significance: Although pressure estimations were underestimated at 24 h post conditioning, the majority of estimated pressures were between the upper and lower pressures used for the conditioning stimulus. Future research is needed to clarify and potentially refine what appears to be a promising method of estimation.