Question about Calorie Expeniture

January 8, 2006

I am training for a half ironman distance triathlon in September of

2006. I am working on my training plan for the year and I have a couple

of questions.

1. I have a Polar s625x heart rate monitor. It stores my sex, age,

height, weight and VO2 max and then calculates calories burned during

exercise. Can this calculation of calories based on this information be

accurate? I have always used as a general rule of thumb that running or

walking a mile, biking 2 miles or swimming a 1/4 mile all burn about 100

calories each. However, my HRM measures my calorie expenditure to be

higher, in particular when I run. I currently do 2 hours of resistance

training a week with a trainer. I also average between 4-7 hours of

cardiovascular work a week. Based on my heart rate monitor, I am

burning 5000-8000 calories a week during exercise alone. This seems

high to me, even though my heart rate on average is in the 150 range.

2. I recently had my resting metabolic rate tested by measuring my

oxygen consumption & heart rate over a 12 minute period while at rest.

Based on this test, my RMR was 30% lower than what was to be expected

for someone of my age, etc. So basically, I have a slow metabolism

according to this test. Is this considered an accurate measure of RMR?

3. I also had my body fat measured using the BodPod. This estimated my

body fat to be 42.8%. I understand the accuracy of this method is

somewhere in the +/- 2% range. I was rather shocked that my body fat

was this high but wonder if it has something to do with a low RMR. Or

am I just fooling myself and I am really eating that much?

4. I understand that exercise really is a small part of the calories

expended during the day. I have read the thread about increasing daily

activity throughout the day. I also recently read some similiar

research out of the Mayo Clinic. At the end of the research, one of the

researchers converted his desk into a treadmill because he was so

convinced of the value of continued movement throughout the day. I am

seriously considering doing something like this at home first. I work

as a chiropractor during the day so I would consider this to be a

lightly active job. Does anyone have any other ideas as to how to

increase a RMR other than to increase activity throughout the day?

Thanks in advance,

E. s, DC

Dublin, OH

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