Effects of Blood Flow Restriction Resistance Training on Autonomic and Endothelial Function in Persons with Parkinson's Disease

Abstract

Background: Autonomic dysfunction precedes endothelial dysfunction in Parkinson's disease (PD) and causes blood pressure and circulation abnormalities that are highly disruptive to one's quality of life. While exercise interventions have proven helpful for motor symptoms of PD, improving associated non-motor symptoms is limited. Low-intensity resistance training with blood flow restriction (LIRT-BFR) improves autonomic dysfunction in non-PD patients and high-intensity resistance training (HIRT) is recommended for motor symptom improvements for people with PD (PwPD).

Objective: To determine the effects of LIRT-BFR and HIRT on homocysteine and autonomic and endothelial function in PwPD and to determine the hemodynamic loads during LIRT-BFR and HIRT in PwPD using a novel exercise protocol.

Methods: Thirty-eight PwPD were assigned LIRT-BFR, HIRT or to a control (CNTRL) group. The LIRT-BFR and HIRT groups exercised three days per week for four weeks. The LIRT-BFR protocol used 60% limb occlusion pressure (LOP) and performed three sets of 20 repetitions at 20% of the one-repetition maximum (1RM). The HIRT group performed three sets of eight repetitions at 80% 1RM. The CNTRL group was asked to continue their normal daily routines.

Results: LIRT-BFR significantly improved orthostatic hypotension (p = 0.026), homocysteine levels (p < 0.001), peripheral circulation (p = 0.003), supine blood pressure (p = 0.028) and heart rate variability (p = 0.041); LIRT-BFR improved homocysteine levels (p < 0.018), peripheral circulation (p = 0.005), supine blood pressure (p = 0.007) and heart rate variability (p = 0.047) more than HIRT; and hemodynamic loads for LIRT-BFR and HIRT were similar.

Conclusions: LIRT-BFR may be more effective than HIRT for autonomic and endothelial function improvements in PwPD and hemodynamic loads may be lessened in LIRT-BFR protocols using single-joint exercises with intermittent blood flow restriction. Further research is needed to determine if non-motor symptoms improve over time and if results are sustainable.

Keywords: Parkinson’s disease; blood flow restriction; endothelial function; exercise; homocysteine5.

Fig. 1

Exercise protocols for the high-intensity resistance training (HIRT) and low-intensity resistance training with blood flow restriction (LIRT-BFR) groups are summarized. The exercise format is pictured in the exact order performed by each group, starting with a warm-up and ending with a cool-down. A sample cuff placement for the blood flow restriction (BFR) protocol is also pictured.

Fig. 2

Homocysteine and peripheral circulation adaptations to four weeks of HIRT and LIRT-BFR. HIRT, high-intensity resistance training; LIRT-BFR, low-intensity resistance training with blood flow restriction; CNTRL, control. The ^*indicates a significant difference compared to HIRT at post-assessments (p < 0.05) and ^#indicates a significant difference compared to pre-assessments (p < 0.05). a) Plasma homocysteine levels. Elevated homocysteine is considered to be above 12μmol/L and is represented by the dotted line. b) Average peripheral circulation, as indicated by transcutaneous oxygen pressure (TcP0₂). The cutoff line is represented by the dotted line at 50 mmHg, with lower pressures indicating poor circulation in the foot.