Heart rate

[Rob3rt]

According to reading I have seen, MHR does change as you gain or lose fitness, but not by much. As you get fitter, MHR reduces are the pumping capacity of the heart increases, or something like that.

As far as I know, changes in MHR are a lot less notable than changes in resting heart rate.

Considering your example, they would go faster and further because their heart can pump more blood per beat making it more efficient, at MHR the body would be getting more oxygen to the muscles than in the initial state. But the MHR would not change by a lot (as far as I know).

You should also know, MHR varies between different sports, your MHR for cycling will not be your MHR for running for example.

 

[black'n'yellow]

Some of this has been dealt with already, but just for the record, here goes....

My understanding is that if you're trying to improve your fitness that you should be training at around 75% of your maximum rate and that doing this will cause you to burn fat. If you train at a rate above around 85% (don't quote me on that figure though) you then burn carbohydrates.

You are right that for low level, general fitness, 75% would not be a bad number to aim for. You are wrong in regard to carb and fat burning. The body burns both fairly equally, all the time. You are burning fat and carbs while you are reading this. It's true that at lower intensities you will burn marginally more fat than carbs, but the percentage is so small as to be insignificant. It also follows that at higher intensities you will burn more of both. So if you are after 'fat burning' - then it might make more sense to engage in high intensity efforts, rather than low intensity.

As a rough guide, the max heart rate for an adult male is 220 minus your age so for an example - if you are a 40 year old male, your max heart rate could be 180 beats per minute.

Forget about 220 - the theory simply does not work for most people. The only way to establish your MHR is to test it.

I have my monitor set to alert me (beeping) at 100% of max heart rate. Generally it doesn't go off although on a few occasions when going up some tough hills it has and I have tended to back off just a little.

All I can say to this is - what you think is your 'max' almost certainly isn't. You don't need to be told by a machine when to back off from MHR. The effort you will be making at MHR will be anaerobic and only sustainable for a few seconds anyway.

 

[Rob3rt]

Some of this has been dealt with already, but just for the record, here goes....



You are right that for low level, general fitness, 75% would not be a bad number to aim for. You are wrong in regard to carb and fat burning. The body burns both fairly equally, all the time. You are burning fat and carbs while you are reading this. It's true that at lower intensities you will burn marginally more fat than carbs, but the percentage is so small as to be insignificant. It also follows that at higher intensities you will burn more of both. So if you are after 'fat burning' - then it might make more sense to engage in high intensity efforts, rather than low intensity.



Forget about 220 - the theory simply does not work for most people. The only way to establish your MHR is to test it.




All I can say to this is - what you think is your 'max' almost certainly isn't. You don't need to be told by a machine when to back off from MHR. The effort you will be making at MHR will be anaerobic and only sustainable for a few seconds anyway.

Both during AND after exercise.

 

[Upstream]

Hi black n yellow,
I have no argument with most of what you say however I think that this statement..

"...It's true that at lower intensities you will burn marginally more fat than carbs, but the percentage is so small as to be insignificant. It also follows that at higher intensities you will burn more of both. So if you are after 'fat burning' - then it might make more sense to engage in high intensity efforts, rather than low intensity".

...isn't quite correct. Global Health and Fitness, quoted within a website briefly states the following;

50 to 60% of your maximum heart rate: In this zone, the body derives it energy by burning 10% carbohydrates, 5% protein and 85% fat
60 to 70% of your maximum heart rate: In this zone, your body fuels itself with 85% fat, 5% protein, and 10% carbohydrate
70 to 80% of your maximum heart rate: You burn 50% of your calories from fat, 50% from carbohydrate, and less than 1% from protein
80 to 90% of your maximum heart rate: The body burns 85% carbohydrates, 15% fat and less than 1% protein in this zone
90 to 100% of your maximum heart rate: While you burn lots of calories per minute in this zone, 90% of them are carbohydrates, 10% fats, and less than 1% protein

I should clarify that I wasn't suggesting that at different exercise intensities that you exclusively burnt one or the other (fat or carbohydrate) but was instead highlighting the one which would be being burnt at a significantly higher rate than the other. Notice that my earlier statement I suggested that carbohydrates would be burnt above around 85%. According to the information contained within the website, I haven't stated anything untrue (85% carbohydrates, 15% fat and less than 1% protein).

 

[black'n'yellow]

Hi black n yellow,
I have no argument with most of what you say however I think that this statement..

"...It's true that at lower intensities you will burn marginally more fat than carbs, but the percentage is so small as to be insignificant. It also follows that at higher intensities you will burn more of both. So if you are after 'fat burning' - then it might make more sense to engage in high intensity efforts, rather than low intensity".

...isn't quite correct. Global Health and Fitness, quoted within a website briefly states the following;

50 to 60% of your maximum heart rate: In this zone, the body derives it energy by burning 10% carbohydrates, 5% protein and 85% fat
60 to 70% of your maximum heart rate: In this zone, your body fuels itself with 85% fat, 5% protein, and 10% carbohydrate
70 to 80% of your maximum heart rate: You burn 50% of your calories from fat, 50% from carbohydrate, and less than 1% from protein
80 to 90% of your maximum heart rate: The body burns 85% carbohydrates, 15% fat and less than 1% protein in this zone
90 to 100% of your maximum heart rate: While you burn lots of calories per minute in this zone, 90% of them are carbohydrates, 10% fats, and less than 1% protein

I should clarify that I wasn't suggesting that at different exercise intensities that you exclusively burnt one or the other (fat or carbohydrate) but was instead highlighting the one which would be being burnt at a significantly higher rate than the other. Notice that my earlier statement I suggested that carbohydrates would be burnt above around 85%. According to the information contained within the website, I haven't stated anything untrue (85% carbohydrates, 15% fat and less than 1% protein).

Sorry - I've no idea how they came up with such bizarre percentages, but I'm not interested in getting into a 'link to a convenient website as proof' competition. As far as I'm aware, fat is not 'burned' at a significantly higher rate than carbs at any point in the exercise range and 60/40 is about as good as it gets. In any case, the only thing that really matters is calories consumed, regardless of the fat/carb content. The higher the intensity, the more calories you will use.

The only other thing to add is that if you are planning on exercising at 50% MHR, you might as well not bother IMO, as you won't see any fitness benefit. You could stay at home and watch a scary movie which would get your heart going quicker than that...

 

[black'n'yellow]

sorry B'n'Y, but that just shows how little you actually know about it. I really dont understand why you seem so intent on destroying as many threads as possible in the way you do....

Matt - sorry I can't help your ignorance - your comment actually shows how little YOU know about it. All I can suggest is you do your own research. The info is all out there, just look for it. Sounds like all I am actually destroying is your own misconceptions - which is your problem, not mine.

 

[Rob3rt]

When aiming to loose weight, whether you burn mostly fat or mostly carbohydrates during exercise is near irrelevant because it is what happens after training that really matters, ultimately though, if you train with a higher intensity you will continue to metabolise fat for a prolonged period following the workout AND you are more likely to burn more total calories, thus more likely to create the calorific deficit required to lose weight. If anyone actually really cares about this stuff please go and read Racing Weight by Matt Fitzgerald and trawl some of his references.

 

[Rob3rt]

B'n'Y has a valid point in where the did all those percentages come from though. Even if we accept the fat burning zone as correct, the following is just a step to far to swallow as read:

50 to 60% of your maximum heart rate: In this zone, the body derives it energy by burning 10% carbohydrates, 5% protein and 85% fat
60 to 70% of your maximum heart rate: In this zone, your body fuels itself with 85% fat, 5% protein, and 10% carbohydrate
70 to 80% of your maximum heart rate: You burn 50% of your calories from fat, 50% from carbohydrate, and less than 1% from protein
80 to 90% of your maximum heart rate: The body burns 85% carbohydrates, 15% fat and less than 1% protein in this zone
90 to 100% of your maximum heart rate: While you burn lots of calories per minute in this zone, 90% of them are carbohydrates, 10% fats, and less than 1% protein

 

[black'n'yellow]

Im not going to get into a tit'for'tat about it all with you and I understand you have your point/s of view, but why be so aggressive about it?? this is a friendly place.

er, what aggression..? This is a 'friendly place' and yet you see fit to accuse me of 'destroying' this thread by simply trying to help understanding. Ironic.

Your post displayed your own ignorance of this topic, while (more irony) claiming that what I was saying was incorrect. Perhaps you could put us all straight then Matt..? Looking forward to hearing your wisdom on the topic.

 

[Rob3rt]

Whether the thread has been destroyed or not at present is debatable, but it will become fact if this turns into another back and forth exchange of "you are wrong", "no, you are wrong". Put forth an argument or walk away.

 

[mr messy]

What was the question again?

 

[Enw.nigel]

Interesting thread. I am certainly not going to mention Maximum Heart Rates!!

 

[derrick]

I don't think i will ask any more questions,










Well not till tommorrow.

 

[sddg7tfl]

3200 miles last year averaging 75% of my maximum heart rate with average ride length of 18 miles.
That's how you get fit/loose weight.

You don't get fit by worrying about heart rates as though you're assembled like a car with a revmeter.

Switch the screen off, get the bike out!

 

[derrick]

3200 miles last year averaging 75% of my maximum heart rate with average ride length of 18 miles.
That's how you get fit/loose weight.

You don't get fit by worrying about heart rates as though you're assembled like a car with a revmeter.

Switch the screen off, get the bike out!

OP was nothing to do with getting fit or loosing weight. my milage last year was a little bit more than yours.