Sometimes people give me a really strange look when I tell them that I sometimes skip the gym and take a walk instead. This heart rate profile illustrates how a walk really can be a good workout, even for a reasonably fit person.
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For the first half of the walk, I kept my heart rate down below 60% exertion. Over this range, I’m not getting the cardiovascular or calorie burning benefits that many other types of exercise would provide. But, I am elevating my heart rate just a little while keeping my muscles and joints moving. This can be a good way to recover from previous workouts while not causing additional stress to the body. It can also be a good way to increase total training time while not drastically increasing the physical stress on the body. When I did this workout, I had been relatively deconditioned due to stress at work and seasonal allergies.
Then, at about the half-way point, I picked up the pace so my heart rate would cross into the aerobic then cardiovascular zones. Notice my heart rate momentarily crosses the anaerobic threshold. This is what a lot of people don’t realize can happen if you are working hard enough. Had I been better conditioned at the time, I could have pushed harder and gotten my heart rate higher. While walking uphill and focusing on using all of the muscle groups in my legs (quads, hamstrings, glutes, and calves) I’ve had my heart rate up as high as 180 beats per minute. No need for the Spinning class or running drills!