Fat Burning Zone Heart Rate

[chrischarles]

I know this question has been asked a lot, maybe in different ways, just searching for answers on the internet alone ended up popping up even more questions than answers.

I do a 6 day training program for cutting and fat loss. I do my cardio (treadmill) at the end of my weight training session for 20 minutes.

I am seeing results, but my fear is either I???m not doing my cardio effectively. Either I am doing cardio too hard and losing the calories that are needed for muscle gain from my weight training, or not doing it hard enough and not losing the proper about of body fat.

Using the Karvonen Formula Heart Rate Calculator, 75% of my max heart rate should fall at around 140-144 for a 37 year old, which according to what I???ve seen online and charts at my gym, should be my ???fat burning zone??? in terms of heart rate.


My question is:

I achieve this heart rate extremely easily with a fast paced walk at about 4 to 4.5 mph, sustained for the entire 20 minute period (able to talk). I do work up a sweat after time, but I do not feel like my body is expending any effort. When I am actually making an effort, let???s say alternating jogging at 7 mph for 7 to 8 minutes (able to talk, but with effort), and walking at 3.5 mph, my heart rate at its maximum is at around 181, and I obviously do feel like I???m making an effort.

I am supposed to feel like nothing is happening for FAT LOSS when hitting my target ???fat burning zone???, or am I just wasting my time and should do high intensity cardio? Will I lose the muscle that I???m working on by doing the high intensity cardio?


I appreciate all the feedback you can give me.

Thanks!

 

[ThreeGigs]

You should feel like nothing is happening, correct.
Even in your 'fat burning zone' (your HR seems a tad high, closer to cardio training), you are burning about 65% fat, 35% carbs. As you exert yourself more, the ratio begins to shift towards carb burning. If you go too hard, fat burning shuts off almost entirely. At 140 BPM, you're probably around 50/50 fat and carbs. Yes, it's a lower percentage, but the amount of fat burned in total is still higher, but not by much.

If you really want to lose fat with cardio, prepare for the long dark tea time of the soul, as you'll be at it for hours. I like to break mine up... slow and steady for 5 mins, all out for a minute, slow for 5, all out for 1, repeat. In an hour, that's 10 intense intervals, and 50 minutes of recovering between them.

 

[Usealittle]

i thought the max rate should be 65-70 not above..... i could be wrong but im pretty sure.

 

[juiceball44]

From what I remember Max heart rate is 200 - your age

 

[Merkaba]

Fat burning zone? What's that?

 

[ThreeGigs]

From what I remember Max heart rate is 200 - your age

Standard is 220 minus your age. But that's *average*, any individual might be 20 BPM over or under that mark.

 

[exphys88]

the concept of "fat burning zone" is referring to the type of fuel that is being used for the exercise. Low intensity exercise uses primarily fat for fuel and as the intensity increases you use more carbs as the fuel source. There is a saying in ex phys, "fat burns in a carbohydrate fire." What this is referring to is that in the mechanism our body uses to burn calories, it starts off with carbs and eventually dips into our your fat stores. In general, you won't dip into your fat stores for energy until you hit the 20 min mark. Most people have about 20 minutes of free fatty acids in their blood stream to use as fuel. After about 20 min, we start to break down triglycerides, which is the form we store fat as.

By staying in the "fat burning zone" you won't necessarily lose more fat. How many calories you eat vs how much you burn is a better determinate. So, when you add some HIIT in there, you actually burn more calories.