Running/walking and Calories Burned

brower47

Some background first (not necessary for the question I want to ask so you can skip to the bottom).

Ok, I have a 1.25 mile track around my property that I run and walk on everyday. I've only just gotten back into running recently so I usually mix them up in order to do five miles a day. My goal, within six months, is to be able to entirely run my five miles a few times a week, walking on non run days (doing other sources of cardio or my rest day).

With that being said, I take lap times of each lap so I can have a nice little record of it here on MFP. My fast walking pace (my first lap to get my legs warmed up) takes roughly 15:30 mins to complete. Then my run takes roughly 12 mins and subsequent 2 walking laps are slower at about 18 mins per lap.

Cals burned for each lap:
Lap 1: 149
Lap 2: 152
Lap 3 & 4: 111

Here's the question:

Why the difference in calories between the fast walk/run laps and the slower laps. For some reason, I always thought that it was more the time spent that would determine calories burned. I know the run lap is more intense but it's also considerably shorter while the slower walking laps (3&4) are less intense but last far longer.

Where's my mental disconnect? It's been a long time since my exercise physiology classes back in college so I must be forgetting something important here. Any insight would be greatly appreciated.

brower47

Anyone?

:blushing: shameless self bump :blushing:

sss92225

The higher effort you put into exercise, the more calories you burn. Your heart rate is higher during the running/fast walking so you burn more calories in a shorter time.

angdpowers

It's different because of ur intensity and heart rate. Increase intensity thus heart rate =s more cals burned

cwolfman13

When you're running, your are performing a more intense workout...therefore your HR is faster...therefore you burn more calories. It is both duration and intensity that determine caloric burn.

Azdak

There is a qualitative increase in aerobic intensity that occurs during running that offsets the decreased amount of time it takes to cover the distance.

When comparing different walking speeds and when comparing different running speeds, speed and duration generally cancel each other so that there is a similar calorie burn per mile. However comparing walking speeds to running speeds, running will burn more calories per mile (except in fringe cases like elite race walkers).

iWaffle

Walking is the most efficient means of locomotion up until you get around 5 mph. At that point it's nearly equivalent to running if you're walking at or above 5 mph. Actually walking 6 mph might burn more calories than running 6 mph because running is more efficient at that speed.

While you're mostly correct that time spent should equal out to the same amount of calories over the same distance it's not totally true. Running and walking really fast just isn't as efficient as a steady easy walk. Your calorie burn per distance traveled increases a little bit because you're sacrificing extra calories to get that same distance covered in less time. You just can't expect to get more time without paying the price somewhere. That's just a law of nature.

Running is superior as an exercise for just this reason mainly. You get more time. It takes me just about 55 minutes to do 6 miles on my morning runs. It would take double the time to do the same thing walking. Since there's no such thing as a free lunch that's going to cost you something somewhere. It just takes more energy. Normally that's a bad thing right. It would be except for the fact that calories are easy to come by but time is something that you just can't buy more of. Good trade off if you ask me.

brower47

Thank you everyone. You've made excellent points and I can see the difference now. The concept of less efficient locomotion really hit it home for me. Hats off to you all.

MinimalistShoeAddict

From Runners World:

How Many Calories Are You Really Burning?
"If you think running and walking both torch the same number of calories per mile, you better put down that cookie"

http://m.runnersworld.com/weight-loss/how-many-calories-are-you-really-burning?page=single

The article above will answer all of your questions

It addresses both running versus walking and total calorie burn (TCB) vs net calorie burn (NCB)

Zekela

Me personally, My heart rate normalizes as I run further. So my first miles I get higher burn and my last miles I get the less amount of burn. Also, my body becomes more efficient (or get used to the run)... for example, my 16 mile runs about a month ago, I was burning about 1500 cals. Now, I'm burning 1400 cals (this is at an 8 mpm pace). This sucks! Also, if I shock my body by going at a less efficient pace (say a 4.5 minute per mile run or a 10 minute per mile run), I burn so much more calories.

skadoosh33

Some background first (not necessary for the question I want to ask so you can skip to the bottom).

Ok, I have a 1.25 mile track around my property that I run and walk on everyday. I've only just gotten back into running recently so I usually mix them up in order to do five miles a day. My goal, within six months, is to be able to entirely run my five miles a few times a week, walking on non run days (doing other sources of cardio or my rest day).

With that being said, I take lap times of each lap so I can have a nice little record of it here on MFP. My fast walking pace (my first lap to get my legs warmed up) takes roughly 15:30 mins to complete. Then my run takes roughly 12 mins and subsequent 2 walking laps are slower at about 18 mins per lap.

Cals burned for each lap:
Lap 1: 149
Lap 2: 152
Lap 3 & 4: 111

Here's the question:

Why the difference in calories between the fast walk/run laps and the slower laps. For some reason, I always thought that it was more the time spent that would determine calories burned. I know the run lap is more intense but it's also considerably shorter while the slower walking laps (3&4) are less intense but last far longer.

Where's my mental disconnect? It's been a long time since my exercise physiology classes back in college so I must be forgetting something important here. Any insight would be greatly appreciated.

Are you sure about the distance? Your first lap would put you at about 4.9mph walk if it's 1.25miles.