Longevity Briefs: A Brisk Walk May Significantly Lower Blood Pressure

Longevity briefs provides a short summary of novel research in biology, medicine, or biotechnology that caught the attention of our researchers in Oxford, due to its potential to improve our health, wellbeing, and longevity.

Why is this research important: Blood pressure inevitably rises with increasing age, and is associated with an increase in the risk of age related diseases including heart disease, stroke and dementia. Physical activity is one of the best ways to lower blood pressure, but many older adults face barriers to doing regular exercise. Yet research shows that even very low levels and durations of exercise provide significant health benefits over remaining sedentary. Walking is a simple and accessible form of physical activity that can be done anywhere and anytime. How much does one need to walk in order to have a beneficial effect on blood pressure? Today’s study set out to answer that question.

What did the researchers do: In this small pilot study, researchers recruited 21 sedentary older adults with high blood pressure. Participants were in their 70s and late 60s. They gave each participant a pedometer and asked them to increase their daily steps by 3000 steps on at least 5 days per week (3000 steps takes roughly 30 minutes at a brisk pace). This intervention lasted 20 weeks, and participants had their blood pressure measured before, during and after the intervention. During the first 10 weeks, participants also had calls with a health coach to help them keep to their goal.

Key takeaway(s) from this research:

• Participants increased their average daily steps from 3899 to 5567 by the end of the intervention
• On average, participants’ systolic blood pressure was reduced by 7 mm Hg by the end of the intervention, while diastolic blood pressure was reduced by 4mmHg – both irrespective of medication
• Participants reported enjoying the intervention
• The lack of a control group means that further randomised controlled trials will be needed to confirm these results

The intervention was mostly successful – by the end of the 10 week period, participants had increased their steps per day from 3899 to 6512 on average, though this dropped down to 5567 at 20 weeks.

At the start of the intervention, participants had an average systolic blood pressure of 137 mm Hg, which dropped to an average of 130 mm Hg by the end of the intervention. This is still considered hypertension, but was a statistically significant decrease. Average diastolic blood pressure decreased significantly from 81 to 77. These changes were not affected by whether or not the participants were taking anti-hypertensive medications. The participants also reported that walking became more of a habit and that they enjoyed the intervention.

It’s important to note that this study had no control group and was relatively small, so it’s possible that the effects of exercise were overestimated. Blood pressure is subject to the placebo effect and regression to the mean – that is to say that if you measure someone’s blood pressure multiple times, it tends to get closer to the population average (mean) each time. This means that we would expect the average blood pressure in a group of hypertensive people to become lower over a 20 week period even if without an intervention, though this probably isn’t enough to account for the full 7 mm Hg reduction that was measured.

How can we apply this knowledge today:

This study suggests that for older adults who find more strenuous exercise and sports difficult, walking may offer an achievable and enjoyable alternative that significantly lowers blood pressure in those with hypertension. Larger randomised controlled trials will be needed to confirm these findings, but most evidence up to this point suggests that even such moderate exercise is likely to benefit both physical and mental health, regardless of age and blood pressure.