Calories burned

Anonymous

njee20 wrote:

1400 = 2 x 700, ergo, it's suggesting that my easy road ride used double the Calories as my MTB race (assuming same length).

Makes no sense. How long was your race?

Tank-slapper wrote:

Your contention was that the figures given by computers for calories burnt are useless. I say they are not.

I still maintain that, although not totally useless, they are hardly reliable.
Take Njee and me, for example. Njee is a superfit racer, who weighs very little, probably about 9.5 - 10 stone.
I'm a big rugby player bloke, and although I am above average fitness, I'm still just a shade under 16 stone.

If me and Njee did the same ride, even at the same pace, MY calorie consumption would be significantly larger, due to a much greater muscle mass, as well as just increased mass.

njee20

Makes no sense. How long was your race?

Only 16 miles, about 4000ft of climbing though, and really muddy, so it was a proper slog, which is reflected in the speed, but the calculations take that to mean I wasn't trying as hard :?

If me and Njee did the same ride, even at the same pace, MY calorie consumption would be significantly larger, due to a much greater muscle mass, as well as just increased mass.

You do put your weight in, but I'm not sure if it actually uses it as a variable. I'm 10.5 stone, so you're 50% heavier, and as you say, would have significantly higher energy requirements!

Anonymous

Its calories per mile though, not hour. Energy is expended in doing things, not by spending time.

njee20

Ah ha, we're back where we're started :-)

In lab conditions yes, but your body uses energy at a rate proportional to how hard it is working. This is not directly and inextricably linked to speed. See the running/cycling example, or road/MTB.

Anonymous

:roll:
Running and cycling are two VERY different ways of using energy. As are road and MTBing.

For example, on an MTB (compared to a roadie), you use energy to overcome the increased bike weight, the increased rolling resistance, etc etc etc

But do a road ride flat out for 20 miles, and a road ride at a leisurely pace on the same bike for 20 miles (whilst avoiding freewheeling), and you should in theory use the same energy.

njee20

But your Garmin doesn't know that, which is my point! **bangs head on wall**

I'm gonna give up. I've never paid the calorie consumption any notice, and will continue to do not. I know exactly what you're saying, but theres too many theoretical assumptions for it to be of any real relevance IMO. Perhaps this is why so many MTBers are rather portly :-)

Anonymous

njee20 wrote:

theres too many theoretical assumptions for it to be of any real relevance IMO

I totally agree. I'm just explaining my thinking that same distance (on same bike/mode of doing something) = same energy.

I also reckon the reason there's a lot of "portly" MTBers is because the vast majority of us are in it for sh*ts and giggles, not for any real fitness benefit.

njee20

I totally agree. I'm just explaining my thinking that same distance (on same bike/mode of doing something) = same energy.

Agreed, but that's the problem that flaws the Garmin - it doesn't know if you're coasting down a 40% gradient with a tail wind or crawling up Mt Everest on your face.

madmole

The older Garmins MASSIVELY overcalculate calories. My old Edge 305 would say 700 calories for an hours blast. My newer Edge 800 says 300 for exactly the same trip

I do a normal sunday trip of 60 miles in 3 hours and I reckon to burn 1200 calories doing that, which seems to tally very well with what I eat and drink

Now dont plan to take all those claories while on the ride. I take a High 5 energy drink mixed in 750 ml or water which lasts me for the whole ride (200 cals). I have a 300 calorie breakfast (Bran) about 1 hour before I set of. and I normall take a gel tube about 10 mins before I climb box hill (another 200). Once I'm home I have a protein/gloucomine shake (another 200 cals) and thats me sorted

So thats 900 cals onboarded (300 breakfast I have every day anyway) and I'm sorted. We cruise at 20 and average 15 mph for the 3 miles

Eat when you are hungry and drink enough to not feel thirsty. Dont ram in calories, your hoping to get fitter not fatter. if your body is like that of the average person then it has plenty or reserves built in

creamsodauk

i can help a bit as i was wearing a calorie monitor for a week fitted by my hospital.

i was at the time around 16 stone and my daily calorie burn was around 2000 for just getting about and for an average of two walks a day i burned another 1400+ calories.

Now i used a programme on my phone called allsport go and my fitness. Both gave pretty accurate readings when i typed in my exercise coupled with its intensity and my weight etc.

So for the cycling part it all comes down to average speed and time. For example a ride at 10mph or less for an hour is around 420 calories.

a ride of 12-14mph average for an hour is 830 calories

(remeber these are for my weight yours will differ) but the counters are fairly accurate if you use a proper average speed taken from a cycle computer or gps etc.

madmole

They cant be accurate

Factors affecting calories burnt, not taken into account by a counter/tables/meter

Head/Tail wind
Gradient
Bike weight
Tyre rolling resistance
Frictional losses on bike
Ghosting rider in front
terrain type (tarmac v gravel etc)
Temperature
Gearing
Clothing resistance
Aerodynamics of the bike
Aerodynamics of your riding position
Heart rate
Body Condition/efficiency
Plus several other I've probably missed

So in short any calculations or tables are a guessing game. The Garmin Edges (new ones) in theory do a good job as they can allow for bike and rider rate, heart rate, cadence (hence gearing), speed, gradient, temperature

Bikes fitted with a power meter are the best as that actually measures real work done (watts and hence calories)

I think folks generally over estimate what they actually burn, its nice to think that a Mars bar doesnt need an hour plus of hard work to burn off

njee20

You're again assuming that speed is the sole variable though, but I CBA to do it all again :-)

Madmole, your figures don't work... 60 miles in 3 hours? Then you say you average 15mph - either it's not 60 miles, doesn't take 3 hours, or you don't average 15mph - you'd have to average 20. I'm also surprised/impressed you can do that on a single bottle of high 5. I did a similar ride today (60 miles in the Surrey Hills, including Box), drank 2 large bottles of high 5 and a can of Coke and I was immensely dehydrated when I got home - not a heavy sweater either.

As an aside, I noticed the software I use to analyse my training (WKO3) uses the power data to give a work figure (but doesn't relate it to calories), which was about 2300kJ today.

madmole

Doesn't include the bottle of water from cafe at top of box hill ( no calories). Gamins average speed always funny on garmin as we normally do 20 - 24 mph on flat, but of course several hill climbs and a couple of good descents. I don't think the edges do a simple distance/time, they remove stops and do strange averages

njee20

You can choose to remove zeros from the average calculations.

jda3000

If you have a power meter, this seems decent

http://www.cycleops.com/index.php/train ... ories.html