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sonik
04-21-2003, 10:46 AM
Ok im trying to get rid of about 10 lbs and turn my 4 pack to a 6 pack and according to a trainer at my gym he told me to do cardio 3 times a week and keep my heart rate at 140 for about 40 minutes. I was under the impression that i would want a higher heart rate but he said your body will use muscle before fat with a higher heart rate? Can someone clear this up. Im 23, 5 9 195

maverick
04-21-2003, 11:34 AM
Since you're about the same stats and the same age as me. its an easy question. Keep it 3 times a week, that should be sufficient. you may want to increase it to 4 days. You want to keep your heart rate at about 70-80% of your MHR(maximum Heart Rate), wich would be 197 beat per minute. So you want to keep your heart rate between 137-158 beats per minute. Do cardio for at least 20 minutes. Do cardio after you lift weights. That way you don't sap your energy for your workout. And of course don't over do yourself. Hope that helps.


:cool:

sonik
04-21-2003, 11:38 AM
so only 20 minutes at an avg of 145bpm? thats better than 40 minutes :)

maverick
04-21-2003, 12:25 PM
No, not only 20 minutes. At least 20 minutes.

PowerManDL
04-21-2003, 12:28 PM
Read the HIIT sticky at the top of the page.

ElPietro
04-21-2003, 12:30 PM
Intervals rule.

Ironman8
04-21-2003, 02:00 PM
IMO, you should do HIIT 2 days a week, and jogging 3 days. That's what I did to lose the fat.

aka23
04-21-2003, 04:00 PM
Originally posted by sonik
Ok im trying to get rid of about 10 lbs and turn my 4 pack to a 6 pack and according to a trainer at my gym he told me to do cardio 3 times a week and keep my heart rate at 140 for about 40 minutes. I was under the impression that i would want a higher heart rate but he said your body will use muscle before fat with a higher heart rate? Can someone clear this up. Im 23, 5 9 195

In my opinion, you did not need to be afraid of using muscle for energy at a higher heart rate.

The primary sources of energy used during traditional cardio are associated with fats and carbs. As intensity increases, the fraction of energy from carbs increases. More calories are burned, so the total number of calories from fat may increase as well. As duration increases, the fraction of energy from fats increases. The fraction of energy from protien/muscle is usually insignificant. It becomes more significant when muscle glycogen levels are very low. This might occur when doing extended cardio on low calorie diets or low carb diets, doing cardio in the morning on an empty stomach, doing cardio immediately after weights when glyogen levels are low, and doing cardio that burns a lot of glycogen such as high intensity for long durations. Even during the most extreme conditions, less than 10% of energy usually comes from protein.

Different authorities set different limits on how much and what type of cardio to do to avoid this. Some bodybuilding sites say limiting it to 20,30,40, or 50 minutes. Some more general sites go as high as 90 minutes. The American College of Sports Medicine recommends 20-60 minutes of work, at 60%-90%MHR, 3-5 times per week. Note that these recommendations fail to mention that energy usage is a function of intensity, as well as duration. It is generally safe to go longer durations, when intensity (%MHR) is lower.

I would suggest doing some traditional cardio, like your trainer recommends; and some high intensity work with shorter durations, such as HIIT. Some studies suggest HIIT benefits reducing body fat more than traditional cardio, even though less fat is burned during the activity. You can reap the most benefits, if you do both activities. Note that you should work up to longer durations and/or higher intensities slowly.

PowerManDL
04-21-2003, 07:20 PM
There's more than "some studies" suggesting HIIT's superiority over endurance cardio.

I can post at least ten right now, in fact, that categorically show this effect in both trained and untrained persons.

The only reason I'd even bother with endurance work would be to either train for an event that requires endurance, or to build up a base for un- or de-trained individuals.

HIIT wins the fat-loss (and several other) arguments hands-down.

Defkon1
04-22-2003, 05:19 AM
Well im sure we'll here lots of theories about wot is best for this all of which are good but more importantly u have to find out wot is good for you.

At least 20 mins is definately a start since you muscles store about that much of glycogen which needs to be used before it'll use fat as an eneergy source but no more than 1 hour. I have research that shows that fat utilisation diminishes at a fast rate after 1 hour so your looking at maintaining cardio for no longer than that unless you were an athlete and that's wot sport required.

We've all heard of periodisation right?? apply this method to you eating. As a former kickboxer the first thing I learned is that fat loss to this degree was all about the kitchen. Take in the carbs on days when u need them, on rest days or even cardio days reduce the carbs u take in. However, bear in mind this is being typed in its simplist form.

Again taking the periodisation technique just do either 1 or 2 weight sessions per week (2 max) and concentrate more on cardio using long duration and HIIT thearies. On gym sessions use only compound movements 1 session at least to failure.

hopes this helps

aka23
04-22-2003, 01:25 PM
Originally posted by Defkon1
At least 20 mins is definately a start since you muscles store about that much of glycogen which needs to be used before it'll use fat as an eneergy source but no more than 1 hour.

You do not need to exercise for 20 minutes to begin using fat as fuel. Your body uses a mixture of fat, glucose, and glycogen as fuel throughout the exercise. The proportions gradually change change as duration increases. Also note that you burn fat all day long, whether you have been exercising for 20 minutes or not. When you are resting, the majority of your fuel usually comes from fat.


Originally posted by Defkon1
I have research that shows that fat utilisation diminishes at a fast rate after 1 hour so your looking at maintaining cardio for no longer than that unless you were an athlete and that's wot sport required.

I would be interested in seeing that research. When glycogen stores decrease, the body utilizes more fat as fuel, not less. This pattern does not change after 1 hour. Costill's studies of treadmill running at 65% VO2 max found fat oxidation accounted for 39% of the energy at the start of the exercise and 67% of the energy 2 hours later. Ahlborg found similar results of increasing fat usage when the exercise continued for 4 hours (at a lower intensity).


Originally posted by Defkon1
Take in the carbs on days when u need them, on rest days or even cardio days reduce the carbs u take in. However, bear in mind this is being typed in its simplist form.

I think calorie intake and exercise are far more important factors that macronutrient balance. You can lose a lot of fat on a high carb diet and on a low carb diet. I have maintaned a near 5% body fat while following a diet that many people would call high carb. If your carb intake gets too low, especially near workouts, it may negatively impact performance and cause you to fatigue earlier and do less exercise.