People should exercise from 20 to 60 minutes, at least three days a week. No debate there, right? Wrong. Recently, the health world has been debating whether exercise periods need to be done all in one chunk, or whether smaller amounts of exercise can be added up over the course of a day to equal 20 to 60 minutes of exercise.
There hasn’t been much research to clarify the debate. The goal of this study was to test the theory that exercise results in the same energy
expenditure (EE) whether done all at once or over the whole day. Thirty women wore a device to measure their EE over three days. On one of the days, they took a brisk 30-minutes walk. On another, they took three brisk 10-minute walks. On the third day, they didn’t do any exercise.
As expected, the walking days resulted in higher EE. But the researchers found that the days of continuous 30-minute walking resulted in significantly higher EE than the days of three 10-minute walks. In fact, the women’s EE rates were higher throughout the day when they took a 30-minute walk, even when they were done exercising.
The authors related a separate study that was recently published. It was done with very overweight subjects and showed opposite results.
It found that breaking the exercise sessions into smaller amounts of time is at least as good as one longer exercise period. The authors of this study aren’t sure what accounts for the differences between the two studies. They suggest more research will be needed to find out which variables affect how, why, and when people exercise.