Is rating of perceived exertion a valid method to monitor intensity during blood flow restriction exercise?

Purpose To examine the concurrent validity of rating of perceived exertion (RPE) in resistance exercise with blood flow restriction (RE+BFR). Methods Twelve trained men participated in an orientation session and 2 experimental sessions: RE+BFR and traditional resistance exercise (TRE). Arm curl and leg extension exercises were standardized by the total volume of 3 sets of 16 repetitions at 35% of 1RM for RE+BFR and 3 sets of 8 repetitions at 70% of 1RM for TRE. BFR was applied to proximal positions of both the upper and lower limbs using an elastic knee wrap with a width of 7.6 cm. The blood lactate concentration (La), RPE in the active muscles (RPE-AM), and in the overall body (RPE-O) were measured at rest and the end of each set using the OMNI-RES. Results In RE+BFR, positive linear regression coefficients (p r = 0.54; leg extension, r = 0.71) and between La and RPE-O (arm curl, r = 0.55; leg extension, r = 0.74). Similarly, in TRE, positive coefficients (p r = 0.63; leg extension: r = 0.63) and between La and RPE-O (arm curl: r = 0.60; leg extension: r = 0.59). Conclusions The RPE scale was shown to be a valid method to monitor and regulate intensity during RE+BFR in the upper and lower limbs.