# How Many Calories

Discussion in 'Health Nutrition and Supplements' started by kokopuffs, Jul 10, 2003.

-T

2. ### Wild survivor New Member

Joined:
Oct 25, 2003
Messages:
6
0
I am 33, 170 Kilo's and about 5' 10". Going by my HR monitor, my max is 170 bpm. On a turbo trainer with a HR of about 135 ish I can burn 400 Kcal every half hour. I was just about to write down my last road results but just realised I never switched over to monitor mode. If you want more info, please ask.

Lee

Joined:
Aug 3, 2003
Messages:
869
0
calculators on station bikes are way off, yesterday i rode
2 hours 48 min with avg hrt 135 i burned 1631 kcals.
if i ride hard 3 hours 3o min i burn 2400.

4. ### Look381i New Member

Joined:
Oct 5, 2003
Messages:
56
0
You didn't read his post carefully. He is saying that calories per unit of time, not per mile, for cycling can be equivalent to jogging, assuming a high rate of power output during the ride.

I have read that a rule of thumb for cycling at 17 mph is 600 calories per hour. Adjust up or down difficulty of terrain, speed, weight of rider and bike, etc.

I have also read elsewhere that cycling burns fewer calories per hour than golf. Having played golf, carrying my own clubs, over hilly courses, and having cycled quite a lot for 30+ years, I can only assume those authors were thinking of cycling at 7 mph or so on a level road.

5. ### M2cycler New Member

Joined:
Jul 30, 2003
Messages:
97
0
i came across this website and found it useful. it tells you the equivalent energy expenditure of cycling to running at different cycling speeds.

http://www.active.com/story.cfm?story_id=5941

hmmm. jan ullrich recently rode a ~47km timetrial in a bit less than an hour. acording to the writer he would have burnt more calories walking around a field and hitting a ball intermittently.

is that article on the internet, i would like to read it.

6. ### Look381i New Member

Joined:
Oct 5, 2003
Messages:
56
0
--The article you link seems to confirm the roughly 600 cal/hr at 17 mph.

I don't remember where I read the cycling/golf comparison, but I think it was in a magazine health or diet article that included a table of various activities and calories burned. Golf was near the bottom, and cycling was below that. As I said, I am sure the author of the table was not thinking of cycling as we know it.

7. ### cincinattikid New Member

Joined:
Jul 21, 2003
Messages:
4
0
Please forgive my naivety, but can someone explain to me why HRM's are so 'useless' for measuring calories burnt during exercise?

I went to a lab and had my VO2max and max heart rates measured. These figures are inputs into my HRM and help calculate an approximation of calories burnt based on the intensity of exercise (reflected as heart rate) and duration. Now why is it that this should be so wrong?? Ive read here that it HAS to be a power X time relationship to get a ball park approximation - well, doesn't the heart rate increase or decrease accordingly depending on the output? And if this is so, isn't it a worthwhile input instead of power (if you dont have a power sensor)?

Even if the approximation is out by say 10%, I could live with that. I would especially appreciate any comments from those PHD's out there

The Kid.

8. ### ric_stern/RST New Member

Joined:
Nov 11, 2002
Messages:
3,866
1
It's not a naive question at all.

Although, as HR increases linearly with VO2, HR can vary under different and the same conditions, depending on many factors (e.g., caffeine use, food, anxiety, temperature, cadence, acute fatigue, chronic fatigue, etc). Thus, at a given workload (power output) HR can vary dramatically (i find that at TT power my HR can vary 15 - 20 b/min).

furthermore, HR lags behind the effort, such that if you do an interval at a given power output HR may not get to where it normally does if the duration is short (or for reasons mentioned above). For e.g. if you ride at TT power for 20 mins, your HR will peak higher than if you do 4 x 5-mins @ TT power. In fact, even if you ride the 5-mins at a higher power than TT power, the long sustained 20-min effort will produce a higher HR. However, riding at TT power for 20mins or TT power as 4 x 5-mins will result in the same energy expenditure.

Mechanical energy expended (kj) = (power/1000) x time (secs)

Estimated energy expenditure (kcal) = MEE (kj).

This is the only way to get a ball park figure. An accurate figure can be calculated in the lab.

It's also important to note that expenditure is dependent upon efficiency (which can only be measured in the lab).

I'm not a PhD yet... the trouble is the approximation will vary wildly depending on what is happening with your HR, cadence, intensity, and the rest of the list i mentioned.

So, if you're trying to track EE for estimating for e.g. energy intake there'll be too many assumptions and errors.

there's some extra info here: http://www.dallastrigeeks.org/Races/IM_Brazil/KP/08-25-2003.html

Ric

9. ### Blimp New Member

Joined:
Dec 29, 2002
Messages:
140
0
Ric,

Some years ago I went on the 'Gutbusters' diet. Briefly, this involved more exercise, and less fat in the diet. I could still drink beer, as long as I 'traded off' beer for more exercise.

Something must have worked, as I lost 17kg.

To you knowledge is their any useful research on the link between beer and cycling - ie., I need to know how far extra I need to ride to burn of a 375ml can of lager.

10. ### cincinattikid New Member

Joined:
Jul 21, 2003
Messages:
4
0

If I may go further, what sort of measurements would the lab need to take into account? They have already provided me with a lactate profile, which includes my anaerobic threshold (equivalent to a workload of 199watts, HR of 130-134 beats/min, and blood lactate concentration of 3.9mM. Max HR 162 and VO2max 56.9ml.kg.min.

The test was done on a stationary trainer.

What other inputs do I require?

Thanks,

The Kid.

11. ### sugametal131 New Member

Joined:
Jan 10, 2004
Messages:
1
0
Hi, I'm a constant biker and i saw you calories per mile. I just found out that when foods list calories, 1 calorie actaully equal 1000 calories (energy needed to heat 1 gram of water 1 degree celcius). Now i'm worried, are you talking food calories or true caloies?

12. ### dhk New Member

Joined:
Sep 1, 2003
Messages:
2,259
0
Yes, unfortunately, we are talking kcal, or kilo-calories in food. The food labels should say kcal, but they usually leave out the "k", at least here in the US. Isn't the rest of the world now using kilojoules for food energy...believe I've seen that on biscuits from the UK.

Power output can also be expressed in kcal/sec, ie, 1 kilowatt=1 kj/sec=.2388 kcal/sec, or 860 kcal/hr. So, if we know power, and the food energy conversion factor, we should be able to calculate calories burned directly.

According to a velo calculator I found online, 150 watts is good for around 17 mph in level, no wind, smooth road conditions. Guys with an accurate power meter hub may be able to validate this number. Anyway, the 150 watt output level converts to 129 kcal of work on the pedals in an hour.

I've seen factors of 20-25% for the energy efficiency of a trained endurance cyclist. Using this range would mean 516-645 kcal/hr are burned at the 150 watt output level. These values bracket the 600kcal/hr @ 17 mph figure....obviously with lots of room for variation!

13. ### Jim's ride New Member

Joined:
Dec 13, 2003
Messages:
39
0
I am 5"11 and 90 kilograms(((FAT)))... Sometimes I ride for 50kms in the hills and the most is 100kms around Adelaide in Australia.
The bike I ride is a \$500 Mongoose Mountainbike (Heavy thing it is)
If I remeber correctly my doctor said I should eat 800 calories per day and it's mainly what you eat during the ride.
Example when i stop at a Red traffic Light and I look like I went for a swim I know the calories are vanishing.
I find it very hard to know what amount of calories I eat during the day. The labels on food products look like i need a degree to understand what's in the product.
Cycling is more like a science these days.
I can't wait to follow the Tour Down Under....

14. ### 2LAP New Member

Joined:
Feb 22, 2002
Messages:
1,265
0
800 calories amounts to about 2.5 chocolate bars, the minimum that is normaly recomended to people who are losing weight 1200 calories (more for men or larger people).

When calculating how many calories you eat, all you need to know are the number of calories per 100g or 1g and the amount you eat. From that you can calculate how many calories have passed your lips.

15. ### dhk New Member

Joined:
Sep 1, 2003
Messages:
2,259
0
The "LA Performance Plan" book states that Lance got a scale and weighed everything he ate when he was losing 12 lbs for the '99 TdF. That would certainly be the disciplined approach.

Concerning calorie levels for dieting and training, I've got a 1981 book called "Coaching Young Athletes", which recommends a calorie deficit of not more than 500-1000 calories per day for someone on a training program, a level which would equate to 1 to 2 lbs/week weight loss.

16. ### 2LAP New Member

Joined:
Feb 22, 2002
Messages:
1,265
0
The same 500 to 1000 calorie advice is still given and works on the basis that a pound of body fat contains 3500 calories. Of course the calorie defocite can be completed by increasing exercise, reducing food intake or both.

17. ### dhk New Member

Joined:
Sep 1, 2003
Messages:
2,259
0
Yes, this book proposed that a 500 calorie/day workout, plus 500 calories diet restriction could produce a healthy weigh loss of 2 lbs per week. Seems to be sound advice for long-term results.

Rather than weighing food, I just try to use the serving info on the packaging as a guideline for calories, carbs and protein.

18. ### TTguy New Member

Joined:
Dec 31, 2003
Messages:
9
0
During aerobic exercise your body can only handle (about) 300 cals. / hr. REGARDLESS of exercise intensity. So, you should not look to replace all the calories expended during exercise...rather strive to replace glycogen expended as it is used. Sorry for brief 'splaination but this is pretty well documented in authoritative places. Glad to point you in that direction if interested.

Joined:
Sep 1, 2003
Messages:
2,259