I don't agree – surely physics say you can't get something for nothing. Riding a bike means carrying an extra 30 lbs or so – the energy has to come from somewhere surely?

This is why you are a graphics designer rather than a physicist 🙂

Okay so to summarize there is no specific answer. So I shall try it and if a become a fatty I shall return to the running.

Tango Man – Member
I was led to believe that it wasn't so much the calories burnt during exercise that counted, but, the raise in your metabolic rate for the 24 hours after the exercise that really burnt the calories.

think this was a good point missed try also "metabolic rate setpoint"
http://www.essortment.com/all/metabolismcalor_rhcm.htm

for me short regular runs seem to promote weight loss while i have to really put in the hours on the bike

This is why you are a graphics designer rather than a physicist

Quite possibly – somebody draw me the explanation then please.

But take it to an extreme – climbing an almost impossibly steep hill – is it easier to run up it or ride up it? I would say run it because with the weight of the bike it becomes impossible to ride it.

Or going down the same hill – it then becomes easier to ride it because gravity does almost all the work for you.

I just don't understand how it is possible to get *free* energy.

for me short regular runs seem to promote weight loss while i have to really put in the hours on the bike

A bit anecdotal but when I was training seriously (!) and running around 55 – 60 miles per week I introduced another 4 short (about 3 miles) early morning runs. I was already quite light (11st 4 and 6ft 1) I recall over the next few weeks I dropped below 11st and had to lower my mileage (I also ate anything that wasnt nailed down!)
My point is that early morning runs do have the effect of increasing your metabolic rate for several hours after. Which burns more fat.

I've done a couple of off-road duathlon events where I'm cycling & running on the same terrain
I always log them & my HRM says that I [roughly] burn twice as many calories – over time – running as I do cycling

Around 900 & 450/hr respectively
whether the actual figures are correct – I don't know but they are both measured with the same equipment on the same day

I think – based on my own observations – that running is not only better at keeping the weight off, but also that it is better for making you look slimmer as it has a much better effect at toning the abs. When I used to do a lot of cycling, but hardly any running, I always used to have a bit of a gut. Now I run more than bike, but overall do less and I don't think I have such an obvious gut – my legs are also more muscular and less like bits of string. Running (I think) is also good for developing strength (as opposed to fitness) and I can now muscle my way up stuff on the bike that I couldn't even when I had more bike fitness – ironic eh?

For overall body shape and injury avoidance it probably also helps to do some core strength stuff such as pilates.

But doing the commute is also making better use of your time, saving you money and putting less CO2 into the atmosphere.

My advice would be do the commute but try and keep up the odd run.

MF – running involves more effort as you are moving your legs more, bouncing your body up and down etc. You are right that on hills this is decreasingly significant. Remember you can freewheel without using any energy – you can do no such thing running.

So it's not "free" energy.

mastiles_fanylion – Member
But take it to an extreme – climbing an almost impossibly steep hill – is it easier to run up it or ride up it? I would say run it because with the weight of the bike it becomes impossible to ride it.

and to go back to the OP and the comment somewhere above that it is physics and biology (physiology?) riding and running up steep hills probably does nothing for fat burning

– i call it fmbs – fatmountainbikersyndrome all out effort uphill and coast downhill to the cafe your body is only too glad to grab and store whatever calories come along just in case you do it again

Fair enough. I prefer running nowadays anyway. Or walking with my iPod on very loud.

🙂

It will depend on your hr and how hard you work at the running/cycling, and how long you spend riding/running.

I'm running about 3 x a week at the moment, and road riding once a week. I use a Polar HRM for both. I burn around about 700 calories per hour running, and between 500 – 600 cycling because my HR is much higher when I run (for example, my 10mile run at the weekend was 179av for 1 hour 19mins and I burnt around 1,000 calories. My 50mile road ride (albeit a social one) was 50miles at an average of 154, and I burnt 2,000 in 4 hours)

Running will burn more as it uses upper body too and there's no coasting/free wheeling. I don't really want to lose weights, but since I've upped my running, I've lost 3kgs and look slimmer. Imo, running has also changed my body as well – my legs look leaner/thinner and i've lost muscle from my hamstrings.

I would agree with rightplacerighttime and keep up the odd run if you want to keep the weight off.

tails, its simple really. start your commute, eat as normal and see what happens. if you gain weight do some running too. job done.
personally i find commuting a good weight control measure done in cojunction with some longer mtb rides, some swimming and occasional spells of running. i only commute when i'm on day shifts (average twice a week of 8 miles each way) and its helps. the effect of 5 commutes a week might surprise you.

There's a lot more to this than the rate you burn calories. I have a Polar HRM that estimates calories based on heart rate, age, weight and a notional level of activity. I don't think it's accurate enough that I could compare my run to my friends, but it's good enough to compare today's run with yesterdays, or last nights run with Sunday's bike ride:

Biking on Sunday – 5 hours in the Peaks at about 800 calories per hour.
Running last night – 70 minutes at about 900 calories per hour.

I wouldn't worry about what the biking is, because if it's hilly then you'll work harder on the climbs, but get a rest on the flat; I've always found my rate of calorie burn doesn't vary much between a flat road bike ride and a hilly MTB ride.

Both those sessions above are very different, but I would say they both took a similar amount out of me as a measure of how able to exercise I feel the following day. I would always say to someone that is talking about exercise as a means to control weight that cycling is the solution, for a number of reasons:

1. If you're over-weight then running has a greater chance of causing injuries due to the impact with each stride.
2. If you have the time you can cycle for a lot longer for the same level of tiredness afterwards; the example above I burned massively more calories cycling than I did running and I'm about as tired today as I was yesterday.
3. Cycling doesn't feel as tough on your body, so you're more likely to enjoy it. If you enjoy it, you'll find more time for it, start looking forward to your exercise and then achieve far better results in your quest to manage your weight.

Running is handy because you can do it on pavements in the dark at night and straight out of your door, but that's really the only thing it has going for it, unless you're doing it because you enjoy it or you want to race.

Hope that helps.

If you just eat when you're hungry and stop eating when you're full up it won't matter how many calories you are burning.

Kev

That doesn't really work in the real world because your brain and stomach adapt themselves to their circumstance a fair bit.

For example, if you stuff yourself silly one night you can stretch your stomach to the point that you can eat more before you get full for a couple of days. If you do this, then eat until you're full your stomach can stay stretched and you'll get fat, all other things being equal.

Similarly, if you swap your three meals a day for 6 half the size, your stomach will contract a bit and your overall intake would fall, applying your rules, and you would then lose weight.

There seem are lot of reference to HRM's I dont really rate these for non elite athletes (flame suit on!)
I also suspect they are innacurate in estimating calorie usage. They only measure HR how do they calculate calories burned?

HRMs aren't much use unless you use them properly; that is use them all the time, upload data to a computer and learn what your heart does etc. Anything else is just information rather than useful information.

My HRM takes your heart rate, age, height and weight and you tell it how active you are. It uses all that to approximate your calorie useage. As I said, I don't think it's accurate enough that I could compare my numbers with someone elses, but it gives an accurate enough picture that I can compare one training session to another. I use the calories as a measure of weekly training volume, rather than a specific tool though.

the raise in your metabolic rate for the 24 hours after the exercise that really burnt the calories.

what tosh :o) That would be a disasterously bad and inefficient design, and the only way for it to work would be for your body temperature to rise to dissipate more heat. When you exercise, stored calories are converted into 20% mechanical energy and 80% heat (so you get hot), and you have to breathe harder to supply the oxygen required. When you stop exercising, you cool and down and stop breathing so hard as this process reduces to the background level

Eat cake of a known calorific value until you can't eat any more.

Go run/cycle whatever.

Come back, eat cake until you can't eat any more. Record amount of cake eaten & calculate amount of calories burnt.

Easy 😀

I read in Mens Health that (on average)…

60 mins cycling = 30 mins running = 10 mins skipping

I read in Mens Health that you should'nt eat fish or any other smelly food before oral sex!

I read in Mens Health that you should'nt eat fish or any other smelly food before oral sex!

I think pineapple is recommended for sweet spunk 🙂 However we are drifting off topic as the fish isn't landed yet…

what tosh :o) That would be a disasterously bad and inefficient design, and the only way for it to work would be for your body temperature to rise to dissipate more heat.

We've done this one before, Simon, and I'm sure you were comprehensively proved wrong then. Can't be bothered to repeat all the arguments, but will just point out that this has been scientifically proven, there is a sound evolutionary reason behind it, and that there are ways for your body to use energy which don't just involve generating heat.

and I'm sure you were comprehensively proved wrong then

I am absolutely certain it hasn't been, it would be like a car giving 200mpg when driven and then consuming 5 gallons a night while turned off 🙂

and that there are ways for your body to use energy which don't just involve generating heat.

oh really ? The pixies eat it ?

"and that there are ways for your body to use energy which don't just involve generating heat."
oh really ? The pixies eat it ?

How do you think exercise makes you fitter?

I am absolutely certain it hasn't been, it would be like a car giving 200mpg when driven and then consuming 5 gallons a night while turned off

Don't really know that much about this, but can spot a crap analogy from a mile off.

At what point during the night is the body "turned off"?

Also, does this have any bearing? – ketosis

can spot a crap analogy from a mile off.

Hence why I didn't think that bit deserved a response!

SFB – it is proven fact that if you exercise you raise your metablic rate for a significant period of time afterwards.

I know its a bit pot kettle and black but you really shouldn't assert your " common sense" arguments without something to back it up.

Also, while aerobic exercise is beneficial for cardiovascular reasons as well as direct calorie burning, recent studies seem to suggest that heavy endurance exercise also increases resting metabolism. However, it is unclear if light cardiovascular training has the same effect.

referenced stuff from wiki follow the references for more

– it is proven fact that if you exercise you raise your metablic rate for a significant period of time afterwards

but without saying how much that is meaningless. After exercise, your body will be repairing muscle, digesting the food you couldn't eat while exercising etc, and it may be that it also leads to more 'active' resting where you move about more, and these things together may be a measurable amount above the nominal resting metabolic rate, and I'm suggesting a small amount, judging by the fact that a few minutes after I stop exercising I calm down and feel exactly the same as normal when I've not been exercising (apart from feeling hungrier), my heart slows to normal, my breathing is normal, so my estimate would for the things mentioned above would be say 20W (above a typical 100W resting metabolic rate) ie almost negligible compared to the hundreds of watts of exercise dissipation. If you know different, give me a number. As for pathways not involving heat, they are not metabolism but anabolism and fat/glycogen storage. Metabolism is measured purely by the amount of oxygen consumed as foodstuffs are broken down, generating mechanical power, heat and carbon dioxide (and urea in the case of proteins)