In this recent study, walking with high intensity bursts of speed improved health benefits compared to moderate walking (and no walking). Here are the definitions of moderate and high intensity walking:
- The moderate-intensity group received instruction to walk more than 8000 steps daily at 50% of peak oxygen capacity for a minimum of 4 days per week, and they used a pedometer to monitor steps.
- The high-intensity group received instruction to do 5 or more daily sets of 2- to 3-minute low-intensity walking intervals (at 40% of maximal oxygen capacity) followed by a 3-minute interval of high-intensity walking (between 70% and 85% of peak oxygen capacity) for at least 4 days per week.
The high intensity group had somewhat better outcomes on these health measurements:
- At the end of the program, muscle strength for knee extension and flexion increased significantly in the high-intensity group (by 13% for extension and 17% for flexion) vs both the nonwalking and the moderate-intensity groups.
- There was significant increase in peak oxygen capacity for walking (increased by 9%) and cycling (increased by 8%) in the high-intensity group vs the nonwalking and the moderate-intensity groups.
- SBP [systolic blood pressure] and DBP [diastolic blood pressure] decreased significantly (by 9 mm Hg and 5 mm Hg, respectively) in the high-intensity group, and the decrease was significantly greater vs the nonwalking and moderate-intensity groups.
- SBP decreased in 25 of 33 participants with increased peak oxygen capacity for walking in the high-intensity group, which suggests a correlation between the blood pressure and peak oxygen capacity.
While neither conclusive nor dramatic, these results do suggest that increasing walking intensity (for at least 15 minutes, in 3 minute intervals, at least 4 days per week) during regular moderate walking may be helpful for some relatively fit people.