High blood pressure is the leading risk factor for death across the globe, affecting 1.13 billion people, resulting in over 10 million deaths in 2019. Clearly high blood pressure is a huge problem, and the issue of treating this condition is much researched. There are many drugs which are effective at reducing blood pressure, but this has still not reduced the overall burden of the condition, potentially due to unwanted side effects. Exercise (aerobic and strength-based) has been shown to reduce blood pressure, but often is quite tiresome and time-consuming. Isometric exercise is a type of resistance training which involves exercises such as wall sits, or hand grips. Isometric exercise however is quick (usually taking just twelve minutes!) to undertake and relatively easy to do!
My team and I recently conducted a systematic review and meta-analysis looking at the effects of isometric exercise on blood pressure (https://www.nature.com/articles/s41440-021-00720-3). Systematic reviews are the highest level of evidence and usually are used to inform clinical practice and health policy.
We found that isometric exercise appears to be safe, in all populations including those with hypertension and older adults. This is an important findings as this was previously unknown and many clinical guidelines have not recommended isometric exercise due to safety concerns.
Importantly, we also found that isometric exercise may significantly reduce blood pressure. We found that it may reduce systolic blood pressure (the top number on a blood pressure reading) by 8mmHg, and diastolic blood pressure (the bottom number) by 4mmHg, both of which are clinically important amounts, similar to many other drugs!
It is important to note that I say isometric exercise “may” reduce blood pressure, because the quality of the studies included in our review was very poor, which limits how much we can trust them and their results. However, it appears unlikely the isometric exercise is dangerous as was once believed and could be another great tool for people living with high blood pressure who don’t like exercising, struggle to make time for exercising or have physical limitations which makes exercising difficult.
Have a read of our study and feel free to contact me if you cannot access the paper!
Reference:
Hansford, H.J., Parmenter, B.J., McLeod, K.A. et al. The effectiveness and safety of isometric resistance training for adults with high blood pressure: a systematic review and meta-analysis. Hypertens Res (2021). https://doi.org/10.1038/s41440-021-00720-3
Harrison Hansford 