Ask any doctor how to lower blood pressure, and “exercise more” will likely be one of the pieces of advice. But the advice is usually quite vague when it comes to type exercise you should do.
Now, a new meta-analysis in Sports medicine offers a clue: exercises combining resistance and aerobic training may stand out for their benefits on blood pressure.
High blood pressure is incredibly common in the United States, affecting between 30 and 50 percent of middle-aged adults, and is a major risk factor for heart disease.
Exercise is one of the best ways to reduce it, but few studies have directly compared different types or examined the relationship between duration and blood pressure, according to Zhongxu Hu, one of the study’s authors and a doctoral student and researcher in exercise and rehabilitation science at Curtin University in Australia.
“The question is no longer simply whether exercise works,” Hu said, “but what types of exercises may work best and how much exercise may be necessary.”
Hu’s team set out to answer these questions by reviewing previous research on exercise and blood pressure. In total, they analyzed 159 studies involving nearly 11,000 adults; participants in each study were on average 45 years old or older.
Ultimately, researchers found that circuit training — alternating between cardio and resistance work, such as lifting weights with relatively short rest periods in between — was associated with the greatest reductions in systolic and diastolic blood pressure.
Next came combination training, or “integrated aerobic-resistance training,” which involved a period of walking, cycling, or other aerobic exercise followed by resistance training.
The researchers also found that the blood pressure benefits increased with more exercise, up to about 1,200 MET minutes per week, the equivalent of about 300 minutes of moderate-intensity exercise or 150 minutes of vigorous exercise, before stabilizing. Circuit training required a lower dose of exercise to achieve maximum benefit, at approximately 580 MET minutes per week.
Some discoveries do not surprise experts.
Most exercise studies suggest “an optimal ‘dose’ of exercise, where more does not improve,” said Jason V. Tso, MD, a cardiologist in the Sports Cardiology Program and Center for Inherited Cardiovascular Disease at Stanford University School of Medicine, who was not involved in the research.
The exercise duration highlighted in the study also roughly matches current public health recommendations, Shah said.
The researchers didn’t look into why alternating between strength and cardio exercises was linked to a greater reduction in blood pressure, but Tso said that aerobic training and strength training both have independent effects on blood pressure. By combining the two, “people probably benefit from both types of exercise.”
The study, however, had important caveats. Participants’ medication use, including the blood pressure medications they were taking, was not systematically reported in the trials; a significant proportion of studies had methodological problems or a high risk of bias; and the quantity and quality of evidence varied between exercise types. For example, data on circuit training and isometric exercises came from fewer trials than data on more common types of training.
“For this reason, the exact rankings should be interpreted with caution,” Hu said. “I think it’s best to view the results as a guide to where the evidence goes, rather than as a final prescription for each individual.”
For now, Hu said we need larger, high-quality randomized trials that directly compare different forms of integrated aerobic resistance training, as well as different programs based on how the exercises are organized.
Despite the limitations, Tso thinks that, generally speaking, it’s a good idea to include strength and endurance exercises in your weekly routine if you’re looking to maintain healthy blood pressure. “People who are just lifting weights should consider cycling or running and (runners) should incorporate at least some regular resistance training,” he suggested.
But the study also indicates that it’s not just the type of exercise that can affect blood pressure, but also the way the exercises are organized. One benefit of alternating between different types of exercises, Tso pointed out, is that it can make workouts more convenient and engaging, especially for older adults who may find repetitive movements difficult or boring.
For anyone with cardiovascular disease or who doesn’t exercise regularly, it’s important to “start small and go slow,” Tso warned. This might mean starting with lighter weights or shorter distances and gradually moving to a new program. According to him, consistency is more important than intensity.
“Listen to your body as you go and take breaks to adapt over time,” Shah said.
“Of course,” Tso added, “if you have a serious illness, be sure to talk with your cardiologist or other relevant doctor first. Different medical conditions have different behaviors that may pose a higher risk.”
Gn Health
