Warlobo

[E]

Hey, I think you must have missed my rebuttle post on "30+30does not equal 60". I was expecting you to argue tha one... ill repost it here for the sake of knowledge and good fun
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Quote:
Much respect WarLobo but I beg to differ with you. Granted 60 minutes of INTENSE cardio will be very effective but... I am of the opinion that the second you get on the machine you are indirectly burning fat because you are burning free calories therefore not giving them the chance to convert into fat. I also feel you start tapping into your fat reserves after only 15-20 minutes of INTENSE cardio. Fat burning is about heart rate and oxygen. If you can stand 60 minute of INTENSE cardio then go for it but 45 minutes should be enough for anyone.
Just my .02
E
P.S. I like 60 mins too but its got to be intense

 

[MS]

There is biochemical validity to your rebuttals as far as they go, but you both neglect the fact that insulin directly inhibits lipolysis so if you have normal to high blood glucose levels then you will not be using as much fat for energy as you would if you exercized on fasting blood sugar. For most folks this is first thing in the morning unless they're on a ketogenic diet. Also in this sitch, you're probably not preventing carbs from being stored as fat by burning them for the same reason (low blood sugar/insulin). Sure, it is better to get out there and do some cardio after a high carb meal instaed of sitting on the couch! But this does not make it the optimal method for burning fat. Exercizing with glucose surging in your veins is a good way to prevent you from GETTING fat as E said. But I believe WarLobo was addressing WOMEN who have been dieting and cardio without the results they're after. Women respond differently to moderate cardio than men, and many women seem to benefit from longer interval cardio sessions.

Another aspect to consider when you're talking about cardio, fat oxidation for ATP etc... is that most female bodybuilders will be doing some form of high intensity weight training while on a restricted carb diet. In this case, there is not necessarily enough carbs in the diet to replenish post weights muscle glycogen AND serve as primary fuel for cardio. You cannot use your fat stores to replenish muscle glycogen and make up the energy deficit. You are better off burning as much fat as you can while doing your cardio, and save the muscle glycogen for the weights. Of course if you do 30 minutes of cardio AFTER a glycogen depleting weights workout you are ahead of the game as long as the post weights catabolism is kept under control.

 

[E]

True point lobo... when it comes to this sport, everyone doesn't always agree and everyone isn't alway right or wrong. There is still so much to be discovered in the feild and nothing is yet set in stone as "the right way" to do something. Maybe thats part of what makes the sport so great is how dynamic it can be.

E

 

[Tellie]

Ok so abou tall of this stuff

I have one little question, So if i wanna just do something small like run to the maailboxes which is like a five min jog then i'd be better off to just drive, becasue it's not doing anything fo rme anyway?

i mean i do do long cardio, but little things like that

 

[cockdezl]

I guess I have to give the evidence for the error of your ways.

First, substrate preference during exercise is not the predictor of weight loss or body composition, it is INTENSITY...which equals calories. The higher the intensity the more calories, the lower the intensity the lower the calories. As I have said before, if you want to burn primarily fat, then don't exercise. Fat is the primary fuel choice at rest, but the caloric demand is nil. At near 100%VO2 Max, glucose (glycogen) is the sole energy source. Who looks better: endurance athletes or sprinters?

Second, intensity levels determine postexercise metabolism, which also plays a part in weight loss. The greater the intensity, the greater the adrenergic response, which elevates metabolism for a longer time.

Also, MS, during exercise, insulin secretion is blunted, since non-insulin dependant glucose transport occurs. Fahey did a study attempting to elevate insulin levels during exercise and this required the consumption of near 2000 cal drinks.

Here are the studies:

Metabolism 1994 Jul;43(7):814-8

"Impact of exercise intensity on body fatness and skeletal muscle metabolism."

Tremblay A, Simoneau JA, Bouchard C.

Physical Activity Sciences Laboratory, Laval University, Ste-Foy, Quebec, Canada.

The impact of two different modes of training on body fatness and skeletal muscle metabolism was investigated in young adults who were subjected to either a 20-week endurance-training (ET) program (eight men and nine women) or a 15-week high-intensity intermittent-training (HIIT) program (five men and five women). The mean estimated total energy cost of the ET program was 120.4 MJ, whereas the corresponding value for the HIIT program was 57.9 MJ. Despite its lower energy cost, the HIIT program induced a more pronounced reduction in subcutaneous adiposity compared with the ET program. When corrected for the energy cost of training, the decrease in the sum of six subcutaneous skinfolds induced by the HIIT program was ninefold greater than by the ET program. Muscle biopsies obtained in the vastus lateralis before and after training showed that both training programs increased similarly the level of the citric acid cycle enzymatic marker. On the other hand, the activity of muscle glycolytic enzymes was increased by the HIIT program, whereas a decrease was observed following the ET program. The enhancing effect of training on muscle 3-hydroxyacyl coenzyme A dehydrogenase (HADH) enzyme activity, a marker of the activity of beta-oxidation, was significantly greater after the HIIT program. In conclusion, these results reinforce the notion that for a given level of energy expenditure, vigorous exercise favors negative energy and lipid balance to a greater extent than exercise of low to moderate intensity. Moreover, the metabolic adaptations taking place in the skeletal muscle in response to the HIIT program appear to favor the process of lipid oxidation.

____________________________________________
Med Sci Sports Exerc 1996 Sep;28(9):1138-43

"Effects of exercise intensity on 24-h energy expenditure and substrate oxidation."

Treuth MS, Hunter GR, Williams M.

USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA. [email protected].

The purpose of this study was to determine: 1) the reliability of 24-h respiratory calorimetry measurements, and 2) the effects of low- versus high-intensity exercise on energy expenditure (EE) and substrate oxidation over a 24-h period. Eight women (age 28 +/- 4.3 yr) were measured for body composition, maximal oxygen consumption while cycling, and EE in three, 24-h calorimeter tests, with identical work output but differing intensity during a 60-min exercise session. Low-intensity (LI) exercise involved continuous cycling at 50% VO2max; whereas high-intensity (HI) exercise involved interval cycling (2 min exercise/recovery) at 100% VO2max. Subjects were randomly assigned to the first two tests at LI or HI, with the third test at the alternate intensity. No differences in EE or respiratory quotient (RQ) during rest, sleep, exercise, or over the 24 h were found between the first two tests (C.V. = 6.0%), demonstrating the reliability of the measurements. The HI protocol elicited significantly higher EE than LI during rest, exercise, and over 24 h, whereas sleeping EE approached significance. No significant differences in RQ during rest, sleep, or over 24 h were found, but 24-h lipid and carbohydrate oxidation were similar in the two protocols. The HI exercise RQ was significantly higher than LI. These findings demonstrated higher 24-h EE in the HI than LI protocol, but similar 24-h substrate oxidation rates.

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Int J Obes Relat Metab Disord 2001 Mar;25(3):332-9

"Impact of high-intensity exercise on energy expenditure, lipid oxidation and body fatness."

Yoshioka M, Doucet E, St-Pierre S, Almeras N, Richard D, Labrie A, Despres JP, Bouchard C, Tremblay A.

Division of Kinesiology, Laval University, Ste-Foy, Quebec, Canada.

OBJECTIVE: Two studies were conducted to assess the potential of an increase in exercise intensity to alter energy and lipid metabolism and body fatness under conditions mimicking real life. METHODS: Study 1 was based on the comparison of adiposity markers obtained in 352 male healthy adults who participated in the Quebec Family Study who either regularly participated in high-intensity physical activities or did not. Study 2 was designed to determine the effects of high-intensity exercise on post-exercise post-prandial energy and lipid metabolism as well as the contribution of beta-adrenergic stimulation to such differences under a real-life setting. RESULTS: Results from Study 1 showed that men who regularly take part in intense physical activities display lower fat percentage and subcutaneous adiposity than men who never perform such activities, and this was true even if the latter group reported a lower energy intake (917 kJ/day, P<0.05). In Study 2, the high-intensity exercise stimulus produced a greater post-exercise post-prandial oxygen consumption as well as fat oxidation than the resting session, an effect which disappeared with the addition of propranolol. In addition, the increase in post-prandial oxygen consumption observed after the high-intensity exercise session was also significantly greater than that promoted by the low-intensity exercise session. CONCLUSION: These results suggest that high-intensity exercise favors a lesser body fat deposition which might be related to an increase in post-exercise energy metabolism that is mediated by beta-adrenergic stimulation.

 

[MS]

You'll get no argument from me cockdez1. If you read the post just down the page from JB3 about cardio gurus, you will see that I argue pretty much the sam thing, especially in terms of any all out maximal effort (such as heavy weight training or sprints) requiring glucose absolutely, and also raising BMR significantly compared to more moderate intensity exercise.

The insulin independent glucose uptake during and following exercize is something I have diabetic clients use to their advantage. The "dawn effect" where diabetics often wake up with lowish insulin/highish blood glucose is an ideal time for them to do their cardio too, since the exercize will result in lower glucose without the need for an insulin injection.

Really, the original question which I think started this whole string of threads was whether or not higher intensity exercise burns more fat than moderate intensity, and wether it is better to consume food before high intensity exercize. The answer to that is clearly that high intensity exercise burns more calories, a lower Percentage of fat for fuel, but still burns significant amounts of fat. In addition high intensity exercize raises the BMR significantly, making it an all around good thing to incorporate into you exercize program. High intensity exercise requires glucose, so food is probably a good idea. I certainly wouldn't weight train or enter a 100M sprint competition on an empty stomach! On the other hand my body is quite happy to do moderate cardio on an empty stomach, and even feels better after I'm 20-30 minutes into it. And since women, unlike men, experience an increase in BMR from moderate intensity exercise, this is a good option for many women.

I guess to me, the confusion comes in when people think of sprint work as "cardio" or "aerobic". There is a large component of aerobics in sprints because of your rest intervals, and WarLobo's thread "why I don't do cardio" is a good example of the aerobic benefits of interval training. But most people would not consider this aerobic in the common sense of the word.

It's all good.

 

[cyberflash]

Hey, this is a great discussion.

In summary,


TO LOSE FAT AND PRESERVE MUSCLES

1) If you have a lot of time in the morning and can spare 60 minutes, do medium-intensity cardio on an empty stomach to enable lipolysis.

2) If you don't have much time and can do only 20-30 minutes of cardio, do high-intensity interval training or maybe even pure high-intensity for the first 10-15 minutes ... to preserve muscles (sprinters' body) and also create a higher metabolic rate for a sustained caloric burn through the day.

TO GAIN MUSCLES

3) If you do intensity workout, better have some carb in your stomach ...

4) Or, eat immediately after you have high-intensity workout on an empty stomach.


Any corrections or additions ?