Combining 30 minutes of morning exercise with short walking breaks throughout the day may help control blood pressure, an Australian study suggests.
Adding three-minute walking breaks to disrupt prolonged periods of sitting benefited older, overweight or obese women in particular, the study authors report in the journal Hypertension.
“Prolonged sitting is a common behaviour in modern society with commuting, work and domestic settings that prompt us to sit,” said lead study author Michael Wheeler of Baker Heart and Diabetes Institute in Melbourne, Australia.
Recent studies have shown that extended sitting during the day can increase blood pressure, which is a key risk factor for heart disease.
“Older adults, in particular, can accumulate lots of sitting throughout the day, with upwards of two-thirds of their day devoted to sedentary behaviours,” he told Reuters Health by e-mail.
Although both exercise and breaks in sitting can reduce high blood pressure, or hypertension, Wheeler and colleagues analysed whether a combination of exercise and short breaks would offer further benefits.
They recruited 67 men and women who were between 60 and 74 years old and overweight or obese. About 4 in 10 participants also had high blood pressure. Every participant completed three different day-long tests in random order, each separated by a minimum of six days. Researchers measured heart rate, blood pressure, blood sugar and other blood markers during each test condition.
In one condition, participants sat uninterrupted for eight hours. In another, they sat for an hour, then walked at moderate intensity for 30 minutes on a treadmill, and sat for the next 6.5 hours. In the third condition, they sat for an hour, did 30 minutes on the treadmill, then returned to sitting, but also did 3-minute walking breaks on the treadmill every 30 minutes for the rest of the day. The treadmill was set at two miles per hour during the exercise bouts, with an incline for the 30-minute morning walking programme and no incline for the 3-minute walking breaks.
During the sitting periods in the study, participants were instructed to read or work quietly on a laptop and avoid activities that may raise blood pressure, such as watching television and making nonessential phone calls.
Overall, the research team found that participants, as a group, had lower average blood pressure, by about 1 mm/Hg, across the day when they were in a test condition that included exercise. The biggest reduction was seen when people did the 30-minute treadmill exercise in the morning and took 3-minute walking breaks throughout the day – although the additional benefit of the walking breaks was seen only among women.
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