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JohnnyB21
06-15-2009, 06:19 PM
I'm working out (lifting) with a trainer 4x/wk. I do cardio for 30 to 45 minutes after each session, plus another day when I don't lift. I vary the cardio between LISS and HIIT.

I think I understand that my body initially uses the sugar stores for energy, and then it uses fat stores, and when those are depleted, it breaks down muscle for energy? Right?

My body fat % is roughy 24%. I could do cardio 6 to 7 days a week! My trainer says to limit my cardio sessions to no more than 30 to 45 min per session so that my body doesn't start to break down muscle for energy. However, I have a lot of fat cells.

I don't understand that if I have plenty of fat cells, then why does my body start breaking down muscle for energy instead of using the fat?

Feel free to use terms like ATP/ADP, lipolysis, etc... to explain. Also, is there a good journal article somewhere explaining this?

Thanks everybody.

Mauler97
06-15-2009, 10:10 PM
I'm working out (lifting) with a trainer 4x/wk. I do cardio for 30 to 45 minutes after each session, plus another day when I don't lift. I vary the cardio between LISS and HIIT.

I think I understand that my body initially uses the sugar stores for energy, and then it uses fat stores, and when those are depleted, it breaks down muscle for energy? Right?

My body fat % is roughy 24%. I could do cardio 6 to 7 days a week! My trainer says to limit my cardio sessions to no more than 30 to 45 min per session so that my body doesn't start to break down muscle for energy. However, I have a lot of fat cells.

I don't understand that if I have plenty of fat cells, then why does my body start breaking down muscle for energy instead of using the fat?

Feel free to use terms like ATP/ADP, lipolysis, etc... to explain. Also, is there a good journal article somewhere explaining this?

Thanks everybody.

No it's not corrrect, many thin people have weeks of fat storage, and many obese people have a years worth so there's no way we could possibly burn energy in that order.

What I've learned is that it is extremely hard-impossible to burn actual body-fat during exercise. I see many people who for the past few months hit cardio extremely hard 4-5 times a week that still look exactly the same as they did when they started.

While doing cardio, as soon as the recently eaten carbs are gone the next quickest source of energy for our body is the glucose stored in our muscles. So really all that cardio just depletes our muscle glycogen, your trainer is right. Also beyond that our body can break down muscle and convert the aminos into glucose also. The truth is when we workout our body uses the most efficent forms of energy it can get, and body-fat is not very efficient.

I know it's hard to be patient, but the only real way to use up stored bodyfat is by having a daily calorie deficit. So you have to focus on calories in versus calories out but be cautious with the calories out part. You can measure to the single calorie how much you have eaten but your calories out is always a guess and there are many variables to it:

#1 Cardio is great for maintaining a weight as it burns up the food you eat so it's hard to have a calories surplus when you do it, but too much of it will make it harder for you to have effective weight workouts and recovery. Also too much of it could actually lower your resting metabolism which is the best way to burn body-fat by making your net calories so low you get stuck in a realy bad case of "starvation mode".

#2 Lifting weights and the process of re-building muscle will help your burn bodyfat, since your body does a lot of the re-building while you rest your metabolsim will have an extra kick for awhile, and resting is the only time our body really likes to use body-fat for fuel.

#3 Eating is the best natural way to boost metabolism, and not eating is the best way to destroy your metabolism.

So eat every 2-3 hours, eat plenty of carbs before and after you workout. Get 20-40g of protein with every meal, get lots of sleep, avoid alcohol, and use cardio as an extra tool not the emphasis of your plan.
If you get stuck on a plateau, take a week off from cardio, eat more and lift hard.
Then when you go back to your diet your metabolism will be fresh and your fat-loss will re-start.

Good luck,

Mauler97
06-15-2009, 10:17 PM
I'm working out (lifting) with a trainer 4x/wk. I do cardio for 30 to 45 minutes after each session, plus another day when I don't lift. I vary the cardio between LISS and HIIT.

I think I understand that my body initially uses the sugar stores for energy, and then it uses fat stores, and when those are depleted, it breaks down muscle for energy? Right?

My body fat % is roughy 24%. I could do cardio 6 to 7 days a week! My trainer says to limit my cardio sessions to no more than 30 to 45 min per session so that my body doesn't start to break down muscle for energy. However, I have a lot of fat cells.

I don't understand that if I have plenty of fat cells, then why does my body start breaking down muscle for energy instead of using the fat?

Feel free to use terms like ATP/ADP, lipolysis, etc... to explain. Also, is there a good journal article somewhere explaining this?

Thanks everybody.

One more thing about the cardio, I've lost 46lbs since January 23rd without a single minute of cardio, mostly because I plan on hitting my goal and maintaining that weight. I don't like doing cardio, so I figured I would try without and it's worked great.

Most of the guys here that do like cardio swear by HIIT training, and recently there was a study that showed 45 minutes of cardio did pretty much nothing for fat-burning and most people here say 15 minutes of HIIT will hit the fat stores. So if I was going to do cardio I stick with doing HIIT almost all of the time.

Birddog6424
06-16-2009, 12:20 AM
No it's not corrrect, many thin people have weeks of fat storage, and many obese people have a years worth so there's no way we could possibly burn energy in that order.

What I've learned is that it is extremely hard-impossible to burn actual body-fat during exercise. I see many people who for the past few months hit cardio extremely hard 4-5 times a week that still look exactly the same as they did when they started.

While doing cardio, as soon as the recently eaten carbs are gone the next quickest source of energy for our body is the glucose stored in our muscles. So really all that cardio just depletes our muscle glycogen, your trainer is right. Also beyond that our body can break down muscle and convert the aminos into glucose also. The truth is when we workout our body uses the most efficent forms of energy it can get, and body-fat is not very efficient.

I know it's hard to be patient, but the only real way to use up stored bodyfat is by having a daily calorie deficit. So you have to focus on calories in versus calories out but be cautious with the calories out part. You can measure to the single calorie how much you have eaten but your calories out is always a guess and there are many variables to it:

#1 Cardio is great for maintaining a weight as it burns up the food you eat so it's hard to have a calories surplus when you do it, but too much of it will make it harder for you to have effective weight workouts and recovery. Also too much of it could actually lower your resting metabolism which is the best way to burn body-fat by making your net calories so low you get stuck in a realy bad case of "starvation mode".

#2 Lifting weights and the process of re-building muscle will help your burn bodyfat, since your body does a lot of the re-building while you rest your metabolsim will have an extra kick for awhile, and resting is the only time our body really likes to use body-fat for fuel.

#3 Eating is the best natural way to boost metabolism, and not eating is the best way to destroy your metabolism.

So eat every 2-3 hours, eat plenty of carbs before and after you workout. Get 20-40g of protein with every meal, get lots of sleep, avoid alcohol, and use cardio as an extra tool not the emphasis of your plan.
If you get stuck on a plateau, take a week off from cardio, eat more and lift hard.
Then when you go back to your diet your metabolism will be fresh and your fat-loss will re-start.

Good luck,


I am going to have to humbly disagree with just about everything you said about the body using fat for energy. And so is science.

Fat oxidation during cardiovascular workouts is well proven by science. Studies showing the efficiency of cardio on fat loss are legion. And fat is an extremely efficient energy source that the bodily uses far more efficiently than muscle protein. Otherwise, we would never be able to burn fat off as efficently as we do, we would lose far more muscle than fat. Whereas in reality, when done properly, a person can have fat loss with little to no muscle loss at all.

There are several ways to measure the efficiency of fat loss after cardio. There is the acute effect, which occurs during cardio and for several hours after. Most of the fat loss occurs during this time. But there is also a long term effect for moderate to high intensity training. This occurs do the effect of EPOC (Excess Post-exercise Oxygen Consumption). This has been proven to increase the RMR (Resting Metabolic Rate) and increase fat oxidation for as long as 24 hours.

Acute and EPOC effects increase fat oxidation. Studies can even be found that show fat oxidation can be quite high even after a pre-workout meal containing carbohydrates. The body will oxidize fat quite well at moderate intensity cardio.

Weightlifting done properly is an excellent means of burning fat, but cardio exercise is awfully tough to beat.

SeanEH
06-16-2009, 04:20 AM
His trainer didn't say no cardio. He said limit cardio. The metabolic differences between a person doing some cardio and a person doing more cardio are not as great as those between a couch potato and a person doing cardio. They're actually probably so negligible that it's really the burn during exercise that counts.

One can only lose weight so fast before significant portions of the weight are going to come from muscle. If the body never touched muscle until fat was gone anorexia would be a good look. Assuming some intake deficit and the activity he's already doing have him losing as fast as he can while minimizing muscle loss, increasing burn with more exercise is going to make the deficit too large, and muscle will increasingly being used for fuel. And if the deficit gets large enough, then all the cited benefits of cardio on metabolism go right out the window, because the body slows down by about 40% in survival mode.

Of course, he could just eat more to avoid that. But eating more to burn more seems somewhat pointless. And if he was eating poorly for quite some time while gaining that weight, calorie restriction can help him re-learn eating habits and change that part of his lifestyle. Too many people never get that part, because I see a lot of cardiosheep trudging away every day in the gym and staying fat.

ramsesthe2
06-16-2009, 05:24 AM
#3 Eating is the best natural way to boost metabolism, and not eating is the best way to destroy your metabolism.

So eat every 2-3 hours, eat plenty of carbs before and after you workout. Get 20-40g of protein with every meal, get lots of sleep, avoid alcohol, and use cardio as an extra tool not the emphasis of your plan.
If you get stuck on a plateau, take a week off from cardio, eat more and lift hard.
Then when you go back to your diet your metabolism will be fresh and your fat-loss will re-start.

Good luck,

Agree with most of what has been posted, but eating small meals ever 3 hours will not increase your metabolism.

Mauler97
06-16-2009, 09:35 AM
I am going to have to humbly disagree with just about everything you said about the body using fat for energy. And so is science.

Fat oxidation during cardiovascular workouts is well proven by science. Studies showing the efficiency of cardio on fat loss are legion. And fat is an extremely efficient energy source that the bodily uses far more efficiently than muscle protein. Otherwise, we would never be able to burn fat off as efficently as we do, we would lose far more muscle than fat. Whereas in reality, when done properly, a person can have fat loss with little to no muscle loss at all.

There are several ways to measure the efficiency of fat loss after cardio. There is the acute effect, which occurs during cardio and for several hours after. Most of the fat loss occurs during this time. But there is also a long term effect for moderate to high intensity training. This occurs do the effect of EPOC (Excess Post-exercise Oxygen Consumption). This has been proven to increase the RMR (Resting Metabolic Rate) and increase fat oxidation for as long as 24 hours.

Acute and EPOC effects increase fat oxidation. Studies can even be found that show fat oxidation can be quite high even after a pre-workout meal containing carbohydrates. The body will oxidize fat quite well at moderate intensity cardio.

Weightlifting done properly is an excellent means of burning fat, but cardio exercise is awfully tough to beat.

I totally respect your post, and thanks for the way you wrote this not turning it in to a flaming war.

We may have to agree to disagree, I've done a lot of reading recently on metabolism and fat burning in order to get myself in shape and stay in shape. I think this could be one of those things we could both find articles on contradicting each other but I found programs designed around cardio to be far less effective at burning fat than those around lifting weights from both my own experience and others at my gym.
This was a recent article post at bb.com last week and it makes a lot of sense to me at least.

http://www.nationalpost.com/story.html?id=1679072

Mauler97
06-16-2009, 09:48 AM
His trainer didn't say no cardio. He said limit cardio. The metabolic differences between a person doing some cardio and a person doing more cardio are not as great as those between a couch potato and a person doing cardio. They're actually probably so negligible that it's really the burn during exercise that counts.

One can only lose weight so fast before significant portions of the weight are going to come from muscle. If the body never touched muscle until fat was gone anorexia would be a good look. Assuming some intake deficit and the activity he's already doing have him losing as fast as he can while minimizing muscle loss, increasing burn with more exercise is going to make the deficit too large, and muscle will increasingly being used for fuel. And if the deficit gets large enough, then all the cited benefits of cardio on metabolism go right out the window, because the body slows down by about 40% in survival mode.

Of course, he could just eat more to avoid that. But eating more to burn more seems somewhat pointless. And if he was eating poorly for quite some time while gaining that weight, calorie restriction can help him re-learn eating habits and change that part of his lifestyle. Too many people never get that part, because I see a lot of cardiosheep trudging away every day in the gym and staying fat.

I'm also not telling him not to do cardio either, I just don't do it because it isn't needed. Like you said cardio=food, so you can eat 2800 calories and burn 400 with cardio, or just eat 2,400 calories it's the same difference pretty much. Also I want to make sure I don't burn what my muscles need.

There is a girl at my club that once had a week where she ate about 1,000 calories day and burned about 300 with 45 minutes of cardio 4 days a week and she gained 4lbs. So I told her that her metabolism was shot, take a week off from cardio and eat whenever you were hungry and shoot for 1,500 cals a day which was her BMR, I also said she may gain some more but this was something she needed to do. That week she didn't gain or lose a pound so the following week I had her alternate her calories 1500 and 1200 and drop her cardio to 2 times a week on her 1200 days and lift weights on her 1500 calorie days that week she lost 6lbs. Now she's still soing it with a Spike Day on the week-end and she's lost 4lbs the past 2 weeks.

Our bodies burn body-fat for 70% of the calories used on our BMR so when that drops during "survival mode" we lose a heck of a lot fat burning.

fatinNYC
06-16-2009, 09:57 AM
i think a lot of the problem here is really the calories in v. calories out. If you do cardio you will burn fat. You just need to not eat more than you burn. I think a lot of people (myself included) have a few problems:

1.) we eat too much even though we think its healthy and underestimate calories
2.) we overestimate our BMR
3.) when we exercise and "burn fat" we slack off the rest of the day because we're tired and we go to sleep early or just lay around the house after - thus negating the exercise
4.) macros in diet are off and our body doesnt have the fuel it needs when it needs it.
5.) we spike our blood sugar at the wrong times.

jerryiii
06-16-2009, 09:57 AM
Duration Classification Energy Supplied By
----------------- -------------------- ---------------------------------------
1 to 4 sec Anaerobic ATP (in muscles)
4 to 10 sec Anaerobic ATP + CP
10 to 45 sec Anaerobic ATP + CP + Muscle glycogen
45 to 120 sec Anaerobic, Lactic Muscle glycogen
120 to 240 sec Aerobic + Anaerobic Muscle glycogen + lactic acid
240 to 600 sec Aerobic Muscle glycogen + fatty acids

Long duration cardio (especially low intensity) uses mostly fat and some glycogen. If glycogen stores are low, the body could convert protein. I agree to limit cardio to 45 min. If you really just walking, then maybe an hour or so.

Edit: Unfortutely the chart did not post right. The last entry is the only one important to this discussion. Basically, its saying the work over 4 min or so is considered aerobic (intensity will be greatly reduce by this point even if starting high) and that the energy systems used burn glycogen and fat.

Birddog6424
06-16-2009, 12:18 PM
I totally respect your post, and thanks for the way you wrote this not turning it in to a flaming war.

We may have to agree to disagree, I've done a lot of reading recently on metabolism and fat burning in order to get myself in shape and stay in shape. I think this could be one of those things we could both find articles on contradicting each other but I found programs designed around cardio to be far less effective at burning fat than those around lifting weights from both my own experience and others at my gym.
This was a recent article post at bb.com last week and it makes a lot of sense to me at least.

http://www.nationalpost.com/story.html?id=1679072

I think you are giving far too much credit to that article, for several reasons. One, they don't list the study or any of the criteria used to measure fat oxidation. It even appears they didn't measure fat oxidation in the body at all. They seem to reference "none posted results". What results did they expect the subjects to report? What type of monitoring did they do?

I'm sure the "stir" it made amongst fitness experts is laughter at the absurdity of their study.

Multiple studies have been well accepted as credible that measure fat oxidation directly in the body. It's irrefutable biology and math. Though I will agree that the long term increase to the RMR via EPOC is not that great (it has been ranged from 3 to 6% depending upon the intensity of the cradio performed) the acute effect of fat oxidation during cardio and within the two to three hour window post exercise is significant. And again, irrefutable.

So I do agree with them that the long term effect is pretty minimal, but the acute effect is not. A person is very hard put to get fat oxidation in the body at a level that can be achieved through cardio.

Here are a few studies that measured fat oxidation directly in the body.

This one is a comparison of fat oxidation in the body in a fasted state with a low GI and a high GI meal consumed post workout, and a low GI and high GI meal consumne pre workout. It also shows fat oxidations acute effects during, one hour after, and two hours after.


1: Appl Physiol Nutr Metab. 2006 Oct;31(5):502-11. Links

Acute effects of exercise timing and breakfast meal glycemic index on exercise-induced fat oxidation.

Bennard P, Doucet E.
School of Human Kinetics, University of Ottawa, Ottawa, ON K1N 6N5, Canada.

Fat balance is an important determinant of energy balance. Exercise after an overnight fast can significantly increase fat oxidation; however, little information pertaining to the effects of exercise and meal glycemic index on fat oxidation under these conditions is available. The objective of this investigation was to study the acute effects of exercise timing and meal glycemic index (GI) on whole-body fat oxidation. Eight apparently healthy young men completed 4 randomly ordered trials during which measurements were made at rest, during exercise, and for 2 h post-exercise and (or) post-prandial. After an overnight fast, subjects were required to perform 400 kcal (1 kcal = 4.184 kJ) of treadmill exercise (at FATmax) either before consuming a 400 kcal low-GI (Ex-LG) or high-GI (Ex-HG) oatmeal breakfast, or after consuming the low-GI (LG-Ex) or high-GI (HG-Ex) meal. The amount of fat oxidized during exercise was significantly greater during Ex-LG and Ex-HG (17.2 +/- 4.0 and 17.5 +/- 4.7 g, respectively) than during LG-Ex and HG-Ex (10.9 +/- 3.7 and 11.7 +/- 3.5 g, respectively) (p < 0.001), as was the amount of fat oxidized during the entire trial (Ex-LG: 23.4 +/- 4.7 g; Ex-HG: 23.4 +/- 6.5 g; LG-Ex: 18.4 +/- 4.7 g; HG-Ex: 19.6 +/- 4.9 g) (p < 0.05), even though energy expenditure was not different across experimental conditions. No significant effect of meal GI on the amount of fat oxidized was noted. Total fat oxidized during exercise, and for 2 h after exercise, was greatest when morning exercise was performed in the fasted state, independently of meal GI.

PMID: 17111004 [PubMed - indexed for MEDLINE]

A chart showing the breakout of fat oxidation (thanks to in10city for creating this)

http://i112.photobucket.com/albums/n179/fcshorthairs/chart.jpg

Here are several others showing the amount of fat oxidized in the body and the optimal range of fat max.


Determination of the exercise intensity that elicits maximal fat oxidation.

Achten J, Gleeson M, Jeukendrup AE.
Human Performance Laboratory, School of Sport and Exercise Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom.

PURPOSE: The aim of this study was to develop a test protocol to determine the exercise intensity at which fat oxidation rate is maximal (Fat(max)). METHOD: Eighteen moderately trained cyclists performed a graded exercise test to exhaustion, with 5-min stages and 35-W increments (GE(35/5)). In addition, four to six continuous prolonged exercise tests (CE) at constant work rates, corresponding to the work rates of the GE test, were performed on separate days. The duration of each test was chosen so that all trials would result in an equal energy expenditure. Seven other subjects performed three different GE tests to exhaustion. The test protocols differed in stage duration and in increment size. Fat oxidation was measured using indirect calorimetry. RESULTS: No significant differences were found in Fat(max) determined with the GE(35/5), the average fat oxidation of the CE tests, or fat oxidation measured during the first 5 min of the CE tests (56 +/- 3, 64 +/- 3, 58 +/- 3%VO(2max), respectively). Results of the GE(35/5) protocol were used to construct an exercise intensity versus fat oxidation curve for each individual. Fat(max) was equivalent to 64 +/- 4%VO(2max) and 74 +/- 3%HR(max). The Fat(max) zone (range of intensities with fat oxidation rates within 10% of the peak rate) was located between 55 +/- 3 and 72 +/- 4%VO(2max). The contribution of fat oxidation to energy expenditure became negligible above 89 +/- 3%VO(2max) (92 +/- 1%HR(max)).[b] When stage duration was reduced from 5 to 3 min or when increment size was reduced from 35 to 20 W, no significant differences were found in Fat(max), Fat(min), or the Fat(max) zone. [b]CONCLUSION: It is concluded that a protocol with 3-min stages and 35-W increments in work rate can be used to determine Fat(max). Fat oxidation rates are high over a large range of intensities; however, at exercise intensities above Fat(max), fat oxidation rates drop markedly.

PMID: 11782653 [PubMed - indexed for MEDLINE]

Cliffs; This study shows fat max oxidation levels are reached at 64% VO2, give or take 4%. Or 74% heart rate max, plus or minus 3%. Fat expenditure above 89% VO2 became negligible.

This one was a study to compare cycling versus running on a treadmill.

http://www.ncbi.nlm.nih.gov/pubmed/12800102?log$=activity



Fat oxidation rates are higher during running compared with cycling over a wide range of intensities.

Achten J, Venables MC, Jeukendrup AE.
Human Performance Laboratory, School of Sport and Exercise Sciences, University of Birmingham, Birmingham, United Kingdom.

The aim of the present study was to compare the intensity that elicits maximal fat oxidation (Fat(max)) determined using a cycle-ergometer and a treadmill-based protocol. Twelve moderately trained male subjects (66.9 +/- 1.8 mL. kg(-1). min(-1)) performed 2 graded exercise tests to exhaustion. One test was performed on a cycle ergometer while 1 test was performed on a motorized treadmill; stage duration during both trials was 3 minutes. Gas exchange measurements and heart rate (HR) recordings were performed throughout exercise. Fat oxidation rates were calculated using stoichiometric equations. Maximal fat oxidation rates were significantly higher during running compared with cycling (0.65 +/- 0.05 v 0.47 +/- 0.05 g. min(-1)). However, the intensity, which elicited maximal fat oxidation, was not significantly different between the cycle ergometer and treadmill test (62.1 +/- 3.1 v 59.2 +/- 2.8% Vo(2)max, respectively). Fat oxidation rates were significantly higher during the treadmill test compared with the cycle ergometer test from 55 to 80%Vo(2)max. Maximal oxygen uptake and maximal HR were significantly higher during the treadmill test. It was concluded that fat oxidation rates were higher during walking compared with cycling. Maximal fat oxidation was 28% higher when walking compared with cycling, but the intensity, which elicits maximal fat oxidation, is not different between these 2 exercise modes.

PMID: 12800102 [PubMed - indexed for MEDLINE]

Cliffs; This was a comparison between two methods that demonstrated the treadmill to be superior to the cycle throughout a larger range of exercise intensities. But both are equal in the fat oxidation at the optimal intensity level. Which was 62% VO2 for the cycle, plus or minus 3%. And 59% VO2 for the treadmill plus or minus 3%. Notice those numbers are close to the first study I posted.

http://www.ncbi.nlm.nih.gov/pubmed/15212756?log$=activity



Optimizing fat oxidation through exercise and diet.

Achten J, Jeukendrup AE.
School of Sport and Exercise Sciences, University of Birmingham, Edgbaston, Birmingham, United Kingdom. jachten@bham.ac.uk

Interventions aimed at increasing fat metabolism could potentially reduce the symptoms of metabolic diseases such as obesity and type 2 diabetes and may have tremendous clinical relevance. Hence, an understanding of the factors that increase or decrease fat oxidation is important. Exercise intensity and duration are important determinants of fat oxidation. Fat oxidation rates increase from low to moderate intensities and then decrease when the intensity becomes high. Maximal rates of fat oxidation have been shown to be reached at intensities between 59% and 64% of maximum oxygen consumption in trained individuals and between 47% and 52% of maximum oxygen consumption in a large sample of the general population. The mode of exercise can also affect fat oxidation, with fat oxidation being higher during running than cycling. Endurance training induces a multitude of adaptations that result in increased fat oxidation.[b]The duration and intensity of exercise training required to induce changes in fat oxidation is currently unknown. Ingestion of carbohydrate in the hours before or on commencement of exercise reduces the rate of fat oxidation significantly compared with fasted conditions, whereas fasting longer than 6 h optimizes fat oxidation. Fat oxidation rates have been shown to decrease after ingestion of high-fat diets, partly as a result of decreased glycogen stores and partly because of adaptations at the muscle level.

PMID: 15212756 [PubMed - indexed for MEDLINE]

Fat loss is studied and often over studied. Any time you see something heavily scrutinized in this manner you will see conflicting studies. However, only 10 to 20% of the information out there seems to go against the grain of what is scientifically proven and anecdotally self-evident. Whilst 80 to 90% of the studies support that fat oxidation during cardio is an excellent means of fat loss and the post workout acute effects of fat oxidation also contribute. I do agree that beyond the three hour mark it is negligible, but it is still there.

It is very difficult to rival the fat oxidation achieved during cardio while using weights. There are certainly ways to do it, but most people don't lift in that manner. They take proper rest periods in between sets, which for hypertrophy, are important.

If you wish to lose fat, do not ignore cardio. Even the best in the game go to the cardio routines when it is time to lose fat.

ramsesthe2
06-16-2009, 12:56 PM
Great info man. So being 25, my optimal HR for fat burning is 145?

DuLac
06-16-2009, 01:11 PM
Birddog, great info. Will rep on recharge.

Birddog6424
06-16-2009, 04:22 PM
Great info man. So being 25, my optimal HR for fat burning is 145?

Heart rate charts are only a rule of thumb based on age. But even for young people such as yourself, there is a broad range of condition levels.

The best thing to do is simply push yourself.

One thing you can do is determine your "max rate". That is the highest output you can manage. Hop on an elliptical or treadmill and see how fast you can go for 20 seconds. That is your max rate. Now to hit the optimum max fat (most fat oxidation) exercise at 60 to 80% of your max rate. If you can't maintain that, then interval it. Go a short resting stage duration, then go 70% for 3 minutes, then rest and repeat.

In the Corp we used to sing cadences as we jogged, and let me tell you that added significantly to the difficulty. If you can talk in complete sentences then you are low intensity, or if you can sing. If you can only get out 6 to 8 hasty words before you need to breathe, that's a good place to be.

That's all loosy goosy of course, but it gives you an idea.

mingo3403
06-16-2009, 04:43 PM
have a deficit and you will lose weight

that is all