Entry 3/18/09

Weight: 233.5 lb I haven't been eating the right foods and no moderate exercise. Now that warmer weather is here I won't have an excuse for not going on at least a 30 minute walk.

This is an article out of Newsmax.com:

“Moderate Intensity” Physical Activity Defined

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. The study is published in the May 2009 issue of the American Journal of Preventive Medicine.

While being monitored for oxygen uptake during walking on a treadmill, 58 woman and 39 men completed four 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. (This comment is my own: If you find this statement contradictory to the rest of the article, you're not alone.)

Lead investigator Simon J. Marshall, PhD, School of Exercise and Nutritional Sciences, San Diego State University, 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."

Newsmax

I think a heart monitor is by far the best way to measure your exercise intensity. You can buy a heart rate monitor you wear on you wrist for about $30. That's not much more than a quality pedometer. Your heart rate should be 65-70% of maximum to be classified as moderate. I do agree that duration of your exercise should be close to 30 minutes to be defined as "moderate".

Also "moderate" is a relative term. If you are in good shape, you will have to do more work to reach the "moderate" level of exercise. This is another reason why a heart monitor is a superior measure. When you start exercising after being sedentary for a long time, your muscles will be smaller. Your heart will have to work harder for you to walk a given distance at a given rate. After a couple of weeks of regular moderate exercise your muscles will be bigger and your blood capillaries will have increased. While this is a good thing, your heart will not have to work as hard as it did in the beginning. So unless you increase your rate and/or time of exercise, the intensity of your heart or cardiovascular workout will begin to flatten out. But if you are monitoring your heartbeat you will always know if you are working your heart and cardiovascular system at a moderate level. You will find that you have to increase the rate of work in a given period to reach the "moderate" level for your heart.

It is also good to have a heart monitor the day you start exercising so you know that you are not working your heart too much and risking a heart attack. This becomes more important as we age. If you have exercised a lot during your life and you've paid attention to the amount of work you did and how you felt you will have an idea of the intensity without a heart monitor but I still recommend one. I wear my monitor almost every time I exercise moderately or aggressively.

Lunch: Five oz. turkey breast, green beans, and garlic spinach. Water with lemon to drink. Ate at Boston Market

Snack: 8 walnuts

Dinner: Grilled chicken (dark meat), beans, grilled veggies,and lots of pico de gallo. Diet coke to drink. Ate at Charro Chicken.