The effects of standard lifestyle advice with isometric exercise training versus standard lifestyle advice with conventional aerobic exercise training upon resting blood pressure

Purpose: Uncontrolled hypertension is associated with risk of strokes, kidney disease and other cardiovascular problems. Standard lifestyle advice is encouraged for uncontrolled hypertension including changes in diet, alcohol intake and smoking levels with physical activity having a significant role within this advice. The current national guideline for physical activity recommends at least 150 minutes of exercise to aid in treating hypertension, however adherence to this exercise advice is very low due to the amount of exercise prescribed. Recently, isometric exercise training (IET) has emerged, and research has demonstrated that it has the same benefits as aerobic exercise but takes less time and could therefore improve adherence overall. Therefore, the aim of this study was to compare the effects of standard lifestyle advice with isometric exercise training against standard lifestyle advice with aerobic exercise training upon resting blood pressure.

Methods: Thirty physically inactive individuals (females n=16 and males n=14) were randomised into a 4-week standard lifestyle advice intervention of IET, aerobic exercise training (AET) or into the control group (standard lifestyle advice with no exercise advice). The IET group consisted of 3 sessions per week carrying out the wall squat at increasing intensity throughout, with 4 x 2-minute holds with 2 minutes of rest in between. The AET group consisted of 5 x 30-minute sessions per week of the participants chosen aerobic exercise at 60-80% of their HRmax. Blood pressure, heart rate and mean arterial pressure was measured using an oscillometric blood pressure monitor (Dinamap® Pro, GEMedical Systems, Slough, UK). Data was analysed using ANCOVA with resting blood measures used as a covariate in the analysis.

Results: Each participant carried out 12 isometric wall-squat sessions or 20 aerobic exercise sessions lasting 30 minutes. The control group did not carry out any form of exercise throughout the duration of the study. Following the 4-week intervention period, standard lifestyle advice with isometric exercise training produced significant reductions in systolic blood pressure (SBP) when compared to the control group (-6.3 mmHg p<0.05). Standard lifestyle advice with aerobic exercise training also produced significant reductions in SBP when compared to the control group (-7.6mmHg p<0.05). However, there were no significant differences in the magnitude of reductions in SBP between the two intervention groups. There were no significant reductions in diastolic blood pressure (DBP), mean arterial pressure (MAP) or heart rate (HR) between groups following the end of the 4-week intervention period.

Conclusion: A short-term intervention of IET produced significant reductions in SBP when compared to the control group. This was also evident for the AET intervention, which also produced significant SBP reductions when compared to the control group. This supports IET as being an efficient and time-saving exercise intervention that can indeed help to reduce SBP in a physically inactive and normotensive population, which can produce similar reductions compared to that of AET which is the nationally recommended exercise intervention for the reduction of high blood pressure.