Examination of the dose-response relationship between isometric resistance training and decreases in blood pressure in both males and females

Isometric training has been shown to produce clinically meaningful reductions in blood pressure, utilising the commonly used protocol (4 x 2-min contractions) three-times a week (Smart et al., 2019). However, one of the main barriers to therapeutic exercise interventions including isometric is time to undertake the intervention and despite the observed benefits, adherence and compliance tends to be low (Lopes et al., 2021). Indeed, regular exercise adherence declines over time, with only 50% of individuals continuing with regular exercise within the first twelve months following the completion of the therapeutic treatment, with a lack of perceived time cited as one of the main barriers (Gee et al., 2012). It is therefore, important to determine if a reduction in the weekly dose of isometric training, such as a reduction in the number of total contractions and therefore a reduced time commitment would produce a similar hypotensive response to those reported with the commonly used protocol.

Our previously funded community focus groups have helped to establish that the isometric exercises used with the ‘iso-band’ (isometric bands designed here at the University) are appropriate and manageable for a range of individuals. However, the feedback from these groups was that undertaking twelve contractions per week may not be sustainable over an 8-12-week period. This evidence further supports the suggestion that time may be a barrier to exercise compliance. Therefore, the aims of this study are to:

•Co-produce a therapeutic isometric exercise protocol that is achievable,
time-efficient, and enjoyable for those participating.

•Determine the dose-response relationship between isometric resistance
training and decreases in blood pressure within the general population.

•Further identify these responses within a number of sub-populations.

•Collect qualitative feedback from participants about the exercise protocol to
internally validate and better establish the therapeutic isometric intervention
to use within the Public Health funded PhD project.

Reference List

Gee ME, Bienek A, Campbell NRC, Bancej CM, Robitaille C, Kaczorowski J, Joffres M, Dai S, Gwadry-Sridar F, & Nolan RP. (2012). Prevalence of, and Barriers to, Preventive Lifestyle Behaviors in Hypertension (from a National Survey of Canadians with Hypertension). The American Journal of Cardiology. 109(4); 570–575.

Lopes S, Félix G, Mesquita-Bastos J, Figueiredo D, Oliveira J, & Ribeiro F. (2021). Determinants of exercise adherence and maintenance among patients with hypertension: a narrative review. Reviews in Cardiovascular Medicine. 22(4); 1271– 1278.

Smart NA, Way D, Carlson D, Millar P, McGowan CL, Swaine IL, Baross AW, Howden R, Ritti-Dias R, Wiles J, Cornelissen VA, Gordon B, Taylor R, & Bleile B. (2019). Effects of isometric resistance training on resting blood pressure: individual participant data meta-analysis. Journal of Hypertension. 37(10); 1927–1938.

Static exercise training reduces blood pressure. The common methods used is to complete four, 2 minute exercise contractions with 2 minutes of rest between the contractions, three-times a week for 4 -12 weeks. However, one of the main barriers to this or any type of exercise is time to undertake the exercise. Despite the observed benefits, sticking to the whole exercise programme seems to be difficult and tends to decline over time, with only 50% of individuals continuing with regular exercise within the first twelve months following the completion of the exercise programme, with a lack of perceived time cited as one of the main barriers. It is therefore, important to determine if a reduction in the weekly dose of static training, such as a reduction in the number of contractions and therefore a reduced time commitment would produce a similar reduction in blood pressure to those reported with the commonly used training plan.