The effects of isometric wall squat exercise on heart rate and blood pressure in a normotensive population

Research suggests that short duration isometric exercise training can reduce resting blood pressure (Wiles et al., 2010: Eur J Appl Physiol, 108, 419-428). However, most training studies involve the use of expensive laboratory based equipment which is ultimately not cost or time effective as a treatment method for hypertension.

The aim of this study was to explore the cardiovascular responses of a simple isometric wall squat exercise at different intensities.

Following ethical approval, 23 normotensive males performed 1 x 2 minute isometric wall squat exercise on 15 separate occasions with a minimum of 4 hours between each visit. During the first 10 randomised visits each participant worked at a different intensity by manipulating the knee joint angle (135°, 130°, 125°, 120°, 115°, 110°, 105°, 100°, 95°, 90°); during the final visits five random intensities were repeated. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and heart rate (HR) were measured at rest and throughout the exercise.

Mean peak values for HR, SBP, DBP and MAP during the wall squat exercise were 129±19.74 bpm, 219±19.74 mmHg, 128±12.46 mmHg and 157±10.74 mmHg respectively. There were statistically significant differences in the blood pressure parameters and heart rate responses with a 10˚ change in joint angle (P<0.05), but not at the 5˚ resolution (P>0.05). The relationships between knee joint angle and all blood pressure parameters and heart rates were linear for all participants (r ranged from 0.685 to 0.971; P<0.05). There was also a linear relationship between HR and SBP for all participants (r ranged from 0.638 to 0.938; P<0.05).

This simple method of performing isometric exercise produced similar responses and linear relationships to that of previous research using complex methods and expensive equipment (Wiles et al., 2005: Journal of Sports Sciences, 23 (8), 795-803). These researchers went on to use their linear relationships to prescribe exercise and alter resting blood pressure using isometric training (Wiles et al., 2010).

From the findings of this study the wall squat exercise could be used in the prescription of isometric exercise training and potentially as a home-based method for reducing blood pressure.