The Perceptual Responses Of Multiple Sclerosis Patients To Traditional Versus Blood Flow Restriction Resistance Exercise

Abstract

PURPOSE: To investigate the perceptual responses (ratings of perceived exertion [RPE] and discomfort [RD]) of multiple sclerosis patients (MS) to low-load resistance exercise (RE) with blood flow restriction (BFR) and to traditional high-load RE without BFR. METHODS: Thirteen individuals (males = 3, females = 10) with a confirmed diagnose of relapsing-remitting MS were randomly assigned to the following RE conditions: 1) low-load RE with BFR (LL-BFR) and 2) high-load RE without BFR (HI). Participants performed 4 sets (30-15-15-15 reps) of bilateral leg press (LP) and knee extension (KE), at 20% of their one-maximum repetition (1-RM), and with 50% of BFR for the LL-BFR exercise trial. For the HI exercise condition, participants completed 4 sets (10-10-10-10 reps) of the same exercises at 70% of 1RM. There was a 3-minute rest period between sets and 5 minutes between exercises. RPE was assessed after each set using the OMNI-RES scale, with scores ranging from 0 to 10. The RD were assessed immediately before and after each set using a visual numeric pain scale, with scores ranging from 0 to 10. Data were analyzed using the Friedman’s and the Wilcoxon non-parametric tests with Bonferroni correction, and with p set at 0.05. Data are winsorized means ± SD. RESULTS: Greater RPE values were observed for the HI exercise condition compared to LL-BFR following the first set of LP (6.83±1.17 vs 4.84±2.05, p < 0.05), but not after sets 2 (6.83±1.48 vs 4.2±2.14), 3 (7.62±1.63 vs 4.82±2.09), and 4 (7.94±1.44 vs 4.98 ± 1.87). During KE, HI elicited significantly (p < 0.05) higher RPE after sets 2 (8.07±1.06 vs 6.47±1.52), 3 (8.86±1.02 vs 6.84±1.26), and 4 (9.02±1.17 vs 6.84±1.26, but not set 1 (8.24±0.66 vs 6.54±1.74). For the RD, LL-BFR induced significantly (p < 0.05) greater RD than HI only after the first set of both LP (2.26±1.46 vs 0.80±0.54) and KE (4.69±1.80vs 2.52±1.65). For the RD measured immediately before each set, LL-BFR was significantly greater (p < 0.05) than HI only before sets 3 (3.13±1.41 vs 0.52±0.68) and 4 (3.14±1.92 vs 1.10±1.09) of LP, and before sets 2 (3.75±1.93 vs 0.94±1.10) and 3 (3.15±1.41 vs 1.15±0.96) of KE. CONCLUSION: LL-BFR results in similar RPE and RD compared to HI. However, the RD perceived immediately before a subsequent set remained partially elevated following some of the sets of LL-BFR.