Calories burned while walking?

So I have a treadmill at home and on my light workout day I walk 3.5mph for 30 mins. I'm trying to figure out how many calories I'm burning and I'm quite confused because I don't know what source to believe. My heart rate monitor watch (that has my info) says I'm burning 190 cals, my treadmill says I'm burning 234 cals and the fitness app says I'm burning 131 cals. Which one do I believe?

I'm female, currently at 152lbs. I like to track EVERYTHING, but I don't want to record the wrong info. Please help me figure this out.

Replies

  • socioseguro
    socioseguro Posts: 1,679 Member
    Hi:
    I would use the lower number and eat back only 50% of the calories.
    It is difficult to measure calories burned accurately.
    I like lifting weights for fitness and health. Calories burned are negligible. I log 1 calorie for lifting weights and call it a day
  • MeanderingMammal
    MeanderingMammal Posts: 7,866 Member
    Walking is pretty easy to calculate:

    0.3* wt in lbs = Cals/ mile

    0.3*152= 45 cals per mile

    So at 3.5mi for 30 minutes you've covered 1.75 miles

    78 calories

    If you're walking then your HR wouldn't get into the range where it's a meaningful indicator of calorie expenditure, hence is overestimating. Your app may be including BMR in the estimate.
  • SueInAz
    SueInAz Posts: 6,592 Member
    Interestingly enough, there's been a rethinking of the formula used to calculate walking calories. The group of scientists who did the recent research have found that larger people see an economy of scale. I've read a few articles on the subject lately. Here's one: http://blog.smu.edu/research/2016/03/14/good-news-youre-likely-burning-more-calories-than-you-thought-when-youre-walking/ Here's the research: http://jap.physiology.org/content/120/5/481.full

    The actual formula is V̇o2total = V̇o2rest + 3.85 + 5.97·V2/Ht

    (where V is measured in m/s, Ht in meters, and V̇o2 in ml O2·kg−1·min−1).

    If you can't figure it out from that formula, it's always best to go with the lower number and be conservative. Be aware that your total calorie burn from exercise includes your BMR or basal metabolic rate -- these are the calories your body would burn even if you were at rest. Your net calorie burn gives you a better idea of how many extra calories you burn from walking. You can roughly figure your net calories per mile by multiplying your weight by 0.30. For you that's 152 * .3 = 45.6 per mile.

    So walking 3.5 MPH for 30 minutes is a distance of 1.75 miles * 45.6 calories per mile. You burned 80 calories above and beyond what you would have burned if you'd just been sitting around.
  • mrp56839
    mrp56839 Posts: 159 Member
    I use a simple formula for running and walking. It comes pretty close to what my hrm guesstimated.

    Weight * miles * .63 = running cals
    Weight * miles * .30 = walking cals.

    I come up with about 109 cals/mi running and that makes sense since most cals say about 100. I'm a little heavier, so if I'm underestimating a little, well, that's calories in the bank.