MADRID, 9 Abr. (EUROPA PRESS) –
Cardiovascular diseases are already the leading cause of death worldwide, and high blood pressure is responsible for 13.8 percent of deaths from this type of disease.
Arterial hypertension is diagnosed when the systolic blood pressure exceeds 140 millimeters of mercury (mmHg) and/or the diastolic pressure exceeds 90 mmHg. It is a multifactorial disorder triggered by problems such as an unhealthy diet, excessive alcohol consumption, smoking, and a sedentary lifestyle.
Beyond a balanced diet, it has been known for some time that strength training is a therapeutic option for hypertension, but the most effective protocols are not sufficiently clear. Now, a study from the State University of São Paulo (UNESP), in Brazil, described in an article published in the journal ‘Scientific Reports’, supports that strength training practiced with a moderate to vigorous intensity two or three times a week is an effective way to mitigate high blood pressure.
The mechanisms underlying the lowering of blood pressure by aerobic exercise are well studied, but little has been done on the effects of resistance exercise on hypertension, based on the data reflected in the review conducted by these investigators.
Led by Giovana Rampazzo Teixeira, a professor in the Department of Physical Education at UNESP in Presidente Prudente, the group analyzed more than 21,000 scientific articles and conducted a Cochrane meta-analysis, considered the gold standard of systematic reviews. According to the authors, the analysis focused on the effects of variables such as age, dose-response training, load, volume, and frequency.
In this study, the sample consisted of 253 hypertensive subjects with a mean age of 59.66 years, and the meta-analysis focused on hypertension responses at baseline and after training in controlled studies evaluating the effects of training over eight years. weeks or more.
“We were particularly interested in the volume and intensity that were considered sufficient to achieve a significant reduction in blood pressure. On average term, eight to ten weeks of strength training led to a 10 mmHg reduction in systolic blood pressure and of.” 4.79 mmHg at diastolic,” Teixeira told the São Paulo State Foundation for Research Protection Agency (FAPESP).
The study showed that the effective results appeared around the twentieth training session. Blood pressure remained lower for about 14 weeks after the training ended. “In clinical practice and in gyms or fitness centers, strength training may be a treatment option for people with arterial hypertension as a non-pharmacological intervention, provided that the key variables are sufficiently known and the objectives are taken into account. of the subject”, has exposed Teixeira.
For a long time, only aerobic training was prescribed to treat high blood pressure, and molecular studies focused almost exclusively on the effects of this type of exercise.
“Strength training was recently included in the Brazilian guidelines on the treatment of arterial hypertension, but much more research is needed to obtain stronger evidence. Future studies should investigate the molecular mediators responsible for lowering vascular and arterial pressure. during strength training”, added Teixeira.
The systematic review searched a total of 21,132 scientific articles in search of large and strong evidence of the effects of resistance training on hypertension. Previous reviews on the subject found such evidence, but this study broke ground by gathering additional evidence on the influence of age, load, intensity, and frequency.
After excluding 21,035 articles that did not meet the review objectives, the investigators excluded 43 of the remaining 97 articles due to duplication, leaving 54 articles for full-text analysis. Fourteen were considered relevant for inclusion in the systematic review.
The results of the analysis showed that resistance training was most effective in reducing blood pressure in protocols with a load intensity of moderate to vigorous, a frequency of at least twice a week and a minimum duration of eight weeks.
Moderate-to-vigorous load intensity was defined as more than 60 percent of the heaviest weight the subjects could lift a single time, known as the one-repetition maximum, or 1RM, such that for a 10kg 1RM, the most effective training load would be more than 6 kg.
Most of the study samples were between the ages of 60 and 68. Only two were younger (18-46). Seven included both women and men, seven only women, and one only men.
A subgroup analysis revealed more about the influence of age on the effects of resistance training, which lowered blood pressure significantly more in the 18-50 age group than in the 51-70 age group. “In any case, strength training can be practiced at any age. The effect on blood pressure is also beneficial in older people,” Texeira explained.
Thus, future studies should investigate the cellular and molecular mechanisms underlying the decrease in blood pressure in response to resistance training.
Current knowledge shows that it elevates heart rate, increases nitrous oxide production, which promotes vasodilation by expanding the diameter of blood vessels, and boosts blood flow.
In the long term, it facilitates adaptations such as a lower resting heart rate, lower blood pressure, greater cardiac efficiency, and higher VO2max, which is the maximum rate of oxygen consumption achievable during vigorous exercise. Usually measured in milliliters of oxygen consumed per kilogram of body weight per minute (ml/kg/min), VO2max is relevant to cardiovascular health.
Among the limitations of the analysis noted by the authors is the inclusion of patients taking antihypertensive medication, such as beta-blockers, diuretics, calcium antagonists, and angiotensin-converting enzyme (ACE) inhibitors, in 11 of the 14 studies. Furthermore, in some studies the inclusion of men and women in the same group precluded a gender-sensitive analysis of the effects of resistance training.
