When a person lifts weights, his or her blood pressure rises during the exercise. But how long does this increase in blood pressure last? If it lasts all day, it could potentially be a problem for untrained or first-time exercisers. Researchers at the University of Maryland sought to find out whether this increase in blood pressure lasted throughout the day.
Thirty-three healthy men and women age 18 to 26 completed the study. They were placed in groups based on their self-reported level of exercise. The categories were sedentary (no regular exercise in the preceding three months), resistance-trained (those who lifted weights three times per week for the preceding 12 months), and endurance-trained (those who exercised at least three days per week for the preceding six months in activities that required prolonged effort, such as long-distance swimming or running).
The participants’ blood pressure was measured at rest before they began exercising. Then they warmed up, stretched, and lifted weights, doing two sets of repetitions on 12 different machines. The workouts lasted 45 to 60 minutes. Afterward, a “walking” blood pressure monitor was attached to the participants for 24 hours while they did their normal activities. Heart rate and blood pressure readings were taken throughout the day and the following night at random times each hour.
Twenty-four hour blood pressure was also measured on a control day. On this day, the participants did no exercise and similar types of daily activities as on the exercising day. Their heart rate and blood pressure were monitored as before.
The results surprised the researchers, who expected that the blood pressure of the sedentary group might remain elevated longer than that of the regular exercisers. But that wasn’t the case. The researchers found no significant difference in blood pressure or heart rate between the groups or between the men and the women on the exercise day compared to the control day. They concluded that the elevation in heart rate during weight training doesn’t last through the following 24 hours in healthy young people.