Globally, cardiovascular diseases (CVD) are the leading cause of death, among those high blood pressure accounts for 13.8% of CVD-related deaths. When systolic blood pressure exceeds 140 mmHg and/or diastolic pressure exceeds 90 mmHg a physician will typically diagnose a patient as having arterial hypertension, and this is a multifactorial disorder that can be triggered by factors such as smoking, drinking too much alcohol, an unhealthy diet, and living a sedentary lifestyle.
The mechanisms behind aerobic exercises lowering blood pressure have been well studied, but the effects of strength training on hypertension have little research. Although strength training is known to be a therapeutic option, there is insufficient clarity as to the most effective approach. This study was launched to provide more clarity, and it was conducted by researchers at São Paulo State University (UNESP) and was led by Giovana Rampazzo Teixeira, who is a professor in UNESP’s Department of Physical Education at Presidente Prudente.
The team analyzed 21,132 scientific articles and conducted a Cochrane meta-analysis that was focused on the effects of variables such as age, training dose-response, load, volume, and frequency. 21,035 articles were excluded for not meeting the objectives of this review, and another 43 were excluded due to duplication, leaving 54 full-text articles of which 14 were considered to be relevant for inclusion in this systematic review.
The study consisted of 253 participants with hypertension with a mean age of 59.66 years old and the meta-analysis focused on the baseline and post-training hypertension responses to controlled studies assessing the effects of strength training for 8 weeks or longer.
The researchers reported that the effective results of strength training appeared at around the twentieth training session, and participant blood pressure levels remained lower for around 14 weeks after the training session ended.
The analysis revealed that strength training was most effective in terms of lowering blood pressure when done at protocols for moderate to vigorous load intensity, at least twice a week, for a minimum of 8 weeks. Analysis of subgroups revealed that blood pressure was lowered significantly more in the 15-50 age group than in the 51-70 age group.
Moderate to vigorous was defined as being more than 60% of the heaviest weight that the subjects could lift just once (1 repetition max or 1RM) so that for a 1RM of 10kg the most effective load would be more than 6 kg.
“We were interested above all in the volume and intensity found sufficient to achieve a significant blood pressure reduction. On average, eight to ten weeks of strength training led to a reduction of 10 mmHg in systolic pressure and 4.79 mmHg in diastolic pressure,” said Teixeira.
“In clinical practice and gyms or fitness centers, strength training can be a treatment option for people with high blood pressure as a non-pharmacological intervention as long as you know enough about the key variables and take the subject’s goals into account,” explained Teixeira.
“Strength training was recently included in the Brazilian guidelines on the management of arterial hypertension, but much more research is needed in order to garner more robust evidence. Future studies should investigate the molecular mediators responsible for lowering vascular and blood pressure during strength training,” Teixeira said.
The study noted that despite certain limitations their findings highlight the potential of strength training as an effective non-pharmacological intervention for managing high blood pressure and improving cardiovascular health.
“In any event, strength training can be practiced at any age. The effect on blood pressure is beneficial in older people, too,” Texeira concluded.
