Calculating body mass index with BMI calculators can be tricky

What is BMI?
The acronym stands for body mass index. It basically tells you whether your body weight is in normal range or not. If not in normal range you should act and either gain or lose weight.

3 zones of BMI
You can be under-weight, normal weight or over-weight. Here’s an accurate chart for your consideration.

Starting your Workout? Consult a Heart Rate Chart before you do!

My resting heart rate was not so low in high school.

In high School, my resting heart rate was between 85 and 110. I became a distance runner and my resting heart rate decreased to as low as 40 BPM over the course of 7 years. It is now around 55.

All that means very little since the thing that was untested is whether the higher heart rate was a cause of increased heart attack risk, or merely a correlated variable.

To learn cause and effect is much more difficult than the correlation that seemed pretty clear. At least in this case there are plausible links:

1. a stronger heart does not need to beat as often reducing the overall wear and tear factor,
2. that arteriosclorsis may cause back pressure that causes the heart to beat more rapidly as well as higher rates of heart attacks,
3. that higher BMI causes results in higher heart rate along with more heart attacks and diabetes,
4. resting heart rate is a general indicator of fitness which is also linked to heart attack and diabetes rates, etc.

But, practically, lower BMI, less arteriosclerosis, lower incidence of heart attack, lower resting heart rate, lower incidence of diabetes, lower blood pressure and general fitness for everyday activities are all results of exercise. Resting heart rate is simply an easy one to measure.

Just another attempt by the “experts” to dictate what is “normal” when in fact people ARE the variables.

Some people live long and healthy lives with a high heart rate, and some with low heart rate and a life filled with cardiovascular exercise, drop dead at fairly young ages. Here’s a heart rate chart for reference.

The same applies to weight, I have always carried a few extra pounds at 5’9″ and around 200lbs, and I have never had any adverse effects from that other than the aggravation caused by people who claim to be health experts complaining about my weight.

Yet, I have met many people who have a family trait of low body fat, very muscular builds, and good conditioning exercise plans, who also had repeated heart bypass surgeries for blocked coronary arteries.

In general when an “expert” tells you “facts” about your lifestyle and health, you should heed the words of an old family practitioner I used to know,

You are your own best physician.

Your body will tell you when you have something wrong, all you need to do it listen to it.

Lots of interesting comments, and good points about not taking bio markers too concretely or literally. However, our notion of normal cardiac biomarkers (such as blood pressure of 120/80, blood glucose levels of under 110, and resting heart rate under 100) are probably way too generous.

The real benchmark is not what you can see in sedentary and overweight Americans, it’s what are the cardiac biomarkers in the original human groups (in other words, in hunter gatherers). These groups had typically a blood pressure of something like 105/75, resting heart rate in the 50s or lower, high insulin sensitivity, and BMI 21 to 23.

This suggests that our notion of what might constitute normal cardiac bio markers are too generous, in the direction of indices of potential trouble. Another major issue is the whole question of what the relationship might be between resting heart rate (indicating a balance or lack thereof between sympathetic and parasympathetic drive) and inflammation, which recent work suggests is really the primary etiological factor in the generation of atherosclerosis. Systemic inflammatory tone (indexed by cytokine ratios and predominance of pro-inflammatory tumor necrosis factor-a and interleukin 6) and sympathetic tone are linked in a complex fashion.

There are several known linkages and probably many that are not.

1. Elevated cholesterol increases NE β receptor expression.
2. Oxidized cholesterol (LDL) drives increased cytokine production from macrophages, linkages between oxidative stress, lipid oxidation, and promotion of inflammation.
3. Activating the SNS, and promoting hypertension, both have pro-inflammatory effects.
4. Beta blockers reduce both IL-6 & CRP.
5. Exercise is anti-inflammatory and reducing markers for oxidative stress, including lipid oxidation.
6. Catecholamines (sympathetic signaling molecules) are inducers of pro-inflammatory cytokines, esp. in macrophages (both α and β receptors).