HRM & Calories Burned

melzteach
melzteach Posts: 550 Member
edited September 23 in Fitness and Exercise
Today is the day 28th of my 90 day journey with P90X.I didn't have a HRM the first couple of weeks and found that I was super hungry. I had a sneaking feeling that the MFP calculations, were not right for me. I got a HRM from Wal-Mart and according to it, I'm burning anywhere from 600-1300 calories depending on the workout. Also I have SUPER bad allergies and this time of year my asthma gives me trouble. I either take Singular or Zyrtec and occasionally nose spray and an inhaler.
I had several thoughts about my high calorie burn today and would love some input. Could taking certain medications (allergy, nose spray, inhaler) raise my heart rate and cause me to burn more calories than 'regular'? Its it possible I have a defective HRM?

I so desperately want to be healthy and lean and I'm terrified I'll do something to mess it up! I'm working hard and exercising every day. I don't want to eat too few calories and screw up my metabolism but I want to loose a bit of weight and feel good about myself. Another bit of a stumbling block is that my family is struggling with finances BIG time. I just can't afford a lot of the things I want to have to help in this big change. Maybe I'm just being impatient and expecting dramatic results in an unreasonable amount of time. Thoughts? Anyone?

Replies

  • samrockrocks
    samrockrocks Posts: 251 Member
    i also have allergies and asthma and use zyrtec, a nose spray, and advair!! my heartrate is elevated because of the steroids. when i exercise, my heartrate spikes up before it evens out. i also bought an HRM and i can walk 3 miles (12 minute) and burn around 700 calories. seems like a LOT, but i've heard often that MFP usually gives you less calories burned than reality!
  • Azdak
    Azdak Posts: 8,281 Member
    If HR is increased because of medication, there is no increase in calories burned. The HRM will give a higher calorie reading but that is an error. Both the 1300 and 700 numbers are way too high.
  • 1300 calories in one hour of P90X is possible... Did you spend the entire workout breathing heavily, dripping sweat, etc? If not, I would question those numbers. If it felt like you were pushing yourself to your limit, then yeah I would probably trust them more or less.

    I don't really like the calorie numbers that my particular heart rate monitor gives me, so instead I take the numbers I get from the HRM and plug them into the calculator at http://www.triathlontrainingblog.com/calculators/calories-burned-calculator-based-on-average-heart-rate/
  • cmj516
    cmj516 Posts: 9
    I think 1300 and 700 calories sound pretty high for what you're doing. I guess it depends on which P90X you're doing, and like someone else said, if you're pushing yourself to your max. If you think you could do it harder and aren't absolutely exhausted when you're done, then its doubtful you burned that many calories. I also think 700 calories from walking 3 miles is extremely high. Personally, and I know it all depends on your fitness and weight, I think the calorie counts from the site are ok. You don't want to overestimate what you're actually burning through exercise and eat more than you should. Your body will let you know if you're eating too few calories, you just have to listen to it.
  • TrainingWithTonya
    TrainingWithTonya Posts: 1,741 Member
    If HR is increased because of medication, there is no increase in calories burned. The HRM will give a higher calorie reading but that is an error. Both the 1300 and 700 numbers are way too high.

    THIS! I, too, am asthmatic. I'm on Zyrtec D daily, and an Albuterol Inhaler when I have an attack. I also have a nebulizer that I use a combination of Albuterol and Atrovent in when I have an attack that the inhaler doesn't control. Because of the stimulant effects of the medication, my resting heart rate is elevated by about 20-30 beats per minute depending on the time from when it was taken and when I've taken my medications. That increase in heart rate doesn't reflect an increase in calories burned because it is just because of the medicine and not actual work being performed. A heart rate monitor doesn't know that, though, and will give a calorie reading thinking that elevated heart rate is from work, so the calorie estimate from a HRM is wrong because of the medication. I'm also in an exercise physiology program and in all of our calculations for calorie estimates, I have to use the METs estimation to get a closer estimate. MFP uses a similar METs compendium to what we use, so I'd go by it if I were you instead of the HRM while you are on medications.

    FYI: The same can happen with caffeine intake, so someone who is exercising within 3-4 hours of coffee or a soda (even diet has caffeine) will have an artificially elevated heart rate and won't get an accurate calorie burn estimate from a HRM. Caffeine has similar brochiodilator effects to asthma medications, too, in addition to the heart rate effects.
  • Lyadeia
    Lyadeia Posts: 4,603 Member
    I don't really like the calorie numbers that my particular heart rate monitor gives me, so instead I take the numbers I get from the HRM and plug them into the calculator at http://www.triathlontrainingblog.com/calculators/calories-burned-calculator-based-on-average-heart-rate/

    I entered my information into that calculator for a few different "known" exercises. I used 35 as VO2 max since I didn't know it. During P90X circuit workouts, I average 165 heart rate...and for my Turbo Kick cardio workouts, I average around 175. The calculations came out to around 600 for the P90X workouts which is what the guide book tells us to estimate. For the Turbo Kick cardio classes, the number was about 520 which is only a few calories different than what MFP estimates when I use "kickboxing including Turbo Jam" as the exercise.

    So perhaps the fitness experts who wrote the P90X program guide book were on to something there...and maybe the guys here at MFP did their homework, too.
  • melzteach
    melzteach Posts: 550 Member
    Thanks for the advice everyone! I'm going to do a little research and I'll let you all know what I find out.
  • melzteach
    melzteach Posts: 550 Member
    For anyone that is interested, I posted a blog with some of the information I found out.
This discussion has been closed.