"Generally, low-intensity activity such as walking alone is not likely going to give anybody marked health benefits compared to programs that occasionally elevate the intensity," said Dr. Vicki Harber, lead author on the Health First study, which was presented recently at the American College of Sports Medicine annual conference.
Dr. Harber and her colleagues, Dr. Wendy Rodgers, Dr. Gordon Bell and Dr. Kerry Courneya of the Faculty of Physical Education and Recreation at the University of Alberta in Edmonton, Canada, were concerned that while people with health issues are encouraged to increase their volume of activity such as walking, there didn't seem to be much focus on the effort that needed to go into the activity.
The University of Alberta study put the popularized pedometer-friendly 10,000-step exercise program to the test against a traditional fitness program which incorporated cardio-based activities on equipment such as treadmills and stationary bicycles. The traditional group was asked to complete exercise at a moderate intensity, a level allowing for one or two sentences of conversation with ease. Intensity was not set for the walking group; they completed their daily exercise at a self-selected pace.
"When we matched the two programs for energy expenditure, we found that the traditional fitness program improved aerobic fitness and reduced systolic blood pressure, more than the 10,000-step lifestyle program," Dr. Harber said. Of the 128 sedentary men and women who completed the six-month research program, those who took part in a more active traditional fitness regimen increased their peak oxygen uptake, an indicator of aerobic fitness, by 10 per cent. Those who took part in the walking program experienced a four per cent increase. Systolic blood pressure also dropped by 10 per cent fo r the traditional fitness group, compared to four per cent for the group who just walked.
Other markers of overall health, such as fasting plasma glucose levels, response to a two-hour glucose tolerance test and various blood lipids were unaffected by either exercise program.
"Our concern is that people might think what matters most is the total number of daily steps accumulated, and not pay much attention to the pace or effort invested in taking those steps," Dr. Harber said. "The 10,000-step or pedometer-based walking programs are great for people--they are motivating, and provide an excellent starting point for beginning an activity program, but to increase the effectiveness, one must add some intensity or "huff and puff" to their exercise. Across your day, while you are achieving those 10,000 steps, take 200 to 400 of them at a brisker pace."
"You've got to do more than light exercise and move towards the inclusion of regular moderate activity, and don't be shy to interject an occasional period of time at the vigorous level."