The benefits of moderate physical activity to general health and well-being are well known. It is recommended that people engage in 150 minutes per week of moderate intensity physical activity, equivalent to 30 minutes each day 5 times a week.
Although pedometers are widely used as a physical activity monitoring tool, they are unable to measure activity intensity.
Researchers have determined that a rate of at least 100 steps per minute achieves moderate intensity activity. Therefore a simple pedometer-based recommendation of 3000 steps in 30 minutes can get people started on a meaningful exercise program.
While being monitored for oxygen uptake during walking on a treadmill, 58 woman and 39 men completed 4 6-minute sessions at different treadmill speeds between 65 and 110 meters per minute. All wore pedometers and their heart rates were recorded. Using 3 METs, or metabolic equivalents, as the minimum level of oxygen demand which approximates moderate exercise, participants were monitored to determine whether they had reached the moderate-exercise level at a given treadmill speed. From these data, the researchers found that for men, step counts associated with walking at 3 METs were between 92 and 102 steps per minute. For women, the range was between 91 and 115 steps per minute.
Although a main finding of this study is that considerable error exists when using pedometer step counts to measure METs during treadmill walking, with only 50% of individuals correctly classified as walking at moderate intensity using step rate alone, the authors suggest that the pedometer can be used as a simple technique for anyone trying to meet exercise guidelines.
Lead investigator Simon J. Marshall states, “We believe that these data support a general recommendation of walking at more than 100 steps per minute on level terrain to meet the minimum of the moderate-intensity guideline. Because health benefits can be achieved with bouts of exercise lasting at least 10 minutes, a useful starting point is to try and accumulate 1000 steps in 10 minutes, before building up to 3000 steps in 30 minutes. Individuals can monitor their progress using a simple pedometer and a wristwatch. The use of a single and simple pedometer-based guideline that is easy both to remember and measure may be more effective in a health communication strategy than the promotion of multiple guidelines and, therefore, messages.”