ding ding ding!!! we have a winner. Sum1 should have stopped this fight ages ago. sedentary ppl= low calorie/carbo needs, athlete=high carb/calorie needs. Pretty simple really.

pretty simply not true, really.

just another bit of unproven dogma.

for anyone who still thinks a high fat diet somehow "chokes" your arteries:

Long term effects of ketogenic diet in obese subjects with high cholesterol level.
Mol Cell Biochem. 2006 Jun;286(1-2):1-9. Epub 2006 Apr 21.
Dashti HM, Al-Zaid NS, Mathew TC, Al-Mousawi M, Talib H, Asfar SK, Behbahani AI.

Department of Surgery, Kuwait University, Safat, Kuwait.

Objective: Various studies have convincingly shown the beneficial effect of ketogenic diet (in which the daily consumption of carbohydrate is less than 20 grams, regardless of fat, protein and caloric intake) in reducing weight in obese subjects. However, its long term effect on obese subjects with high total cholesterol (as compared to obese subjects with normal cholesterol level is lacking. It is believed that ketogenic diet may have adverse effect on the lipid profile. Therefore, in this study the effect of ketogenic diet in obese subjects with high cholesterol level above 6 mmol/L is compared to those with normocholesterolemia for a period of 56 weeks. Materials and methods: In this study, 66 healthy obese subjects with body mass index (BMI) greater than 30, having high cholesterol level (Group I; n = 35) and those subjects with normal cholesterol level (Group II; n = 31) were selected. The body weight, body mass index, total cholesterol, LDL-cholesterol, HDL-cholesterol, urea, creatinine, glucose and triglycerides were determined before and after the administration of the ketogenic diet. Changes in these parameters were monitored at 8, 16, 24, 32, 40, 48 and 56 weeks of the treatment. Results: The body weight and body mass index of both groups decreased significantly (P < 0.0001). The level of total cholesterol, LDL cholesterol, triglycerides and blood glucose level decreased significantly (P < 0.0001), whereas HDL cholesterol increased significantly (P < 0.0001) after the treatment in both groups. Conclusion: This study shows the beneficial effects of ketogenic diet following its long term administration in obese subjects with a high level of total cholesterol. Moreover, this study demonstrates that low carbohydrate diet is safe to use for a longer period of time in obese subjects with a high total cholesterol level and those with normocholesterolemia.

Uh... this is a low-carb diet on OBESE SUBJECTS. Certainly not your average TDF rider. And it said nothing about how much fat they ate... Cholesterol is not the same as fat, BTW.

Of the two study groups, obese and not, how much did they eat? I bet the obese group ate fewer calories than they burned off each day.

I'd love to see someone can average over 25mph in a 10mile-TT and ride 400-miles+ a week survive on a ketogenic diet. Fine for an obese couch potatoe who doesn't exercise, certainly not something a fit athlete could live on.

I posted the study because

1) OP is a casual cyclist who wanted to lose weight (not a 25 mph time trialist)

2) several posters have responded that a low carb diet is unhealthy, blah blah blah, one even blamed his unfortunate heart disease on meat/cholestoral issues. I just wanted to point out that these views are based more on dogma than actual science. the actual science is steadily disproving these notions.

now, as to whether nor not someone can do your TT at 25 mph on a low carb diet, you could be right, I honesly dont know. at that level, perhaps you do need carbs. but that is irrelevant to OP's concerns. Regarding the 400 miles per week on a low carb diet, that is certainly doable, and I would argue easier to do for an athlete who has adapted to a high fat/low carb diet, as you do not bonk, you do not have the lactic acid issues, etc. etc.

Yeah, so many variables and we can debate this forever. Personally I don't think the diet makes that big of a deal really. If you want to lose weight, you gotta eat fewer calories than you burn off. That's the one constant that's not debatable regardless of the composition of your diet. High-fat/low-carb only works for low-intensity and endurance riding. Even those "adapted" to high-fat/low-carb diet still burn 100% glycogen at LT or above.You can ride long miles, but you can't be doing it very fast. So you're not gonna see a world-class TDF or Olympic athlete doing that.


If you want to cite articles, here's another one:
------------------------------------------------------------------------------
http://jap.physiology.org/cgi/conten...ract/80/4/1173

Journal of Applied Physiology, Vol 80, Issue 4 1173-1179, Copyright © 1996 by American Physiological Society

ARTICLES
Body fat and exercise endurance in trained rats adapted to a high-fat and/or high-carbohydrate diet

R. A. Lapachet, W. C. Miller and D. A. Arnall
Department of Kinesiology, Indiana University, Bloomington 47405, USA.

To study how diet composition affects exercise endurance and body composition, 48 male Sprague-Dawley rats were treadmill trained for 8 wk while consuming either a high-fat (F) diet or high-carbohydrate (C) diet. The diets were switched for one-half the number of rats in each group 3 days before the animals were killed, during which feeding time the rats did not exercise. One-half of rats receiving each of the four diet combinations were taken at rest (R) or exhaustion (E), resulting in eight groups: CCR, CFR, FFR, FCR, CCE CFE, FFE, and FCE. An analysis of variance revealed that resting glycogen in the FCR group was enhanced in muscle (19-33%) and liver (23%) compared with controls. Each F group's exercise time to exhaustion [CFE, 322.9 +/- 25.0; FFE, 356.8 +/- 37.8; FCE, 467.0 +/- 32.6 (SE) min] was different (P < 0.05) from control (CCE, 257.5 +/- 29.2 min). Postexercise glycogen was equivalent among all dietary groups, were muscle triglycerides. The FF and FC groups had higher 3-hydroxyacyl-CoA dehydrogenase activity in soleus muscle than either CC or CF animals. After training, body weights were similar between the two dietary groups; however, percent body fat was 17% greater after the F diet, even though F diet animals voluntarily consumed 12% less energy than did C diet animals. These data suggest that exercise endurance time is optimized in trained rats that receive a carbohydrate load after adaptation to a F diet. However, despite intense exercise training, the F diet promotes body fat deposition, and the health consequences of following such a regimen are still unknown.

Here's another article using cyclists:
------------------------------------------------------------------------
http://jap.physiology.org/cgi/content/full/82/4/1185#T1

Journal of Applied Physiology Vol. 82, No. 4, pp. 1185-1189, April 1997
METABOLISM - Effects of diet on muscle triglyceride and endurance performance

Raymond D. Starling, Todd A. Trappe, Allen C. Parcell, Chad G. Kerr, William J. Fink, and David L. Costill

Human Performance Laboratory, Ball State University, Muncie, Indianapolis, Indiana 47306

ABSTRACT

Starling, Raymond D., Todd A. Trappe, Allen C. Parcell, Chad G. Kerr, William J. Fink, and David L. Costill. Effects of diet on muscle triglyceride and endurance performance. J. Appl. Physiol. 82(4): 1185-1189, 1997.---The purpose of this investigation was to examine the effects of diet on muscle triglyceride and endurance performance. Seven endurance-trained men completed a 120-min cycling bout at 65% of maximal oxygen uptake. Each subject then ingested an isocaloric high-carbohydrate (Hi-CHO; 83% of energy) or a high-fat (Hi-Fat; 68% of energy) diet for the ensuing 12 h. After a 12-h overnight fast, a 1,600-kJ self-paced cycling bout was completed. Muscle triglyceride measured before (33.0 ± 2.3 vs. 37.0 ± 2.1 mmol/kg dry wt) and after (30.9 ± 2.4 vs. 32.8 ± 1.6 mmol/kg dry wt) the 120-min cycling bout was not different between the Hi-CHO and Hi-Fat trials, respectively. After the 24-h dietary-fasting period, muscle triglyceride was significantly higher for the Hi-Fat (44.7 ± 2.4 mmol/kg dry wt) vs. the Hi-CHO (27.5 ± 2.1 mmol/kg dry wt) trial. Furthermore, self-paced cycling time was significantly greater for the Hi-Fat (139.3 ± 7.1 min) compared with the Hi-CHO (117.1 ± 3.2 min) trial. These data demonstrate that there was not a significant difference in muscle triglyceride concentration before and after a prolonged moderate-intensity cycling bout. Nevertheless, a high-fat diet increased muscle triglyceride concentration and reduced self-paced cycling performance 24 h after the exercise compared with a high-carbohydrate diet.
.....
DISCUSSION
... In summary, muscle triglyceride concentration was not significantly different before and after 120 min of submaximal cycling. Nevertheless, the ingestion of a high-fat diet increased muscle triglyceride concentration by 36%, 24 h after the cycling bout. Furthermore, a high-carbohydrate diet did not increase muscle triglyceride concentration but did increase muscle glycogen storage and improve self-paced cycling performance compared with a high-fat diet.
------------------------------------------------------------------------

Basically confirms the previous study I quoted. A high-fat diet packs more triglycerides (fat) into the muscle cells and reduces the amount of glycogen available. You end up with weight-gain and lower energy levels. You're not able to ride as fast and not as far. If you're trying to lose weight and have a fixed amount of time to do it each week, say 5 or 10 or 15-hours, you want to be burning off as many calories/hr as possible for the fastest weight-loss rate.

your first study involved rats, not humans, enuff said there.... at least my study involved human beings, albeit fat ones, ha haa

as for the second one, it's been shown by other studies that an athlete switching over from a high carb to a high fat diet needs to allow for an adjustment period. Your study didn't, so it is pretty much meaningless.

Your study only showed cholestrol levels in the body, it said nothing about performance differences or the longevity of such changes. So what physiological and metabolic attributes change with this "adjustment period"? Specifically in relation to:

- total calories burned per day
- percentage fat vs. carbs burned at 50%, 67, 75, 85, 100% MHR?
- VO2 max
- power-generated at LT and VO2mx (what's the spread between them)
- time-to-fatigue at LT, max-endurance, etc.
- recovery time, can you do it day after day
- fitness improvement rate over years (look at diet of those who get to cat-1 within 2-years of racing)

The one variable that's not controlled and equalized in a lot of these studies is the calories-in vs. calories-out ratio. That's what you want to focus on in weight-loss, just about everyting else is secondary.

Really that study suggested that we should adapt to high fat diet then carb load before races.

Low carb induction followed by a high carb diet (1 week of each during a 2 week taper) has been done for a long time by many endurance athletes as a way of tricking your body into storing extra glycogen. You end up with more glycogen than a continuous high carb diet.

Yup, carbo-loading... age-old performance trick.. :)

like I said, my only point was that anyone who says you should avoid a low carb diet because it's bad for your heart does not know what you are talking about.

the performance thing is another story. there are loads of studies that suggest you can do just as well on low carb, given a long enough adaption period. I gather your body gets better at storing and utilizing fat as fuel. also, even for the non athlete, your body has to adjust - different enzymes are required blah blah blah.. anyway, the only exception appears to be efforts at the very highest levels of intensities... some of these studies are referenced and disputed earlier in this thread... I'd dig some up, but it's Friday night in the big city so I am outta here!

I'll give you that. I think it's overeating that's the real cause of obesity and health problems. You can pile one fat by eating more than you burn off with any kind of diet, be it low-carb/high-carb/low-fat/high-fat/low-protein/high-protein. Your body will end up storing the excess as blubber regardless. There are however, conversion-to-fat efficiencies that differ.

Sure, the one thing I'd like to see is a comparison of two things in terms of performance:

- power-generated at VO2-max and LT
- time-to-exhaustion at VO2-max or LT

Ketogenic Diets and Physical Performance
 

[QUOTE=FatguyRacer]I disagree. (Is'nt the internet great!) A low carb diet for an active cyclist is not the way to go. Maybe for a bodybuilder or powerlifter, but not an endurance athlete.

I recommend a fascinating article by Stephen D. Phinney published in the August, 2004 issue of Nutrition & Metabolism entitled Ketogenic Diets and Physical Performance. Phinney compared performance of a group of cyclists on high carb diet to their performance (same group after a period of adaptation) on a ketogenic diet. Phinney found there was no loss of speed or endurance if attention was given to maintaining potassium and nitrogen balance for the group in the ketogenic mode. He did find that under conditions of short duration (anerobic exercise such as sprinting or weight lifting) a high carb diet yields superior performance.

Full text of the article: http://www.nutritionandmetabolism.com/content/1/1/2

Dave Brown

Diet should be about a way of eating that will keep you healthy for the rest of your life. There are common-sense ways to do that through eating quality food, lots of fruits and vegatables, and low-glycemic index carbs. If you're an athlete, you need to add in high-glycemic carbs as an energy source.

Though it can help people lose weight, atkins is not a lifetime diet. I know many people who have gone off of it and are now heavier, and there are cardiac risk elements.

South beach, on the other hand, can be a lifetime diet. It has limits on high-glycemic carbs and fats, which seem to be the big problem for most people.

There's no substitute for a healthy diet. You can choose to have whatever opinion you want. I eat healthy, my blood work is great, and I'm 6'2" and 165 pounds. I think I'll keep eating the way I do.

oh no not this thread again!!!!!!!!!!

why can't Atkins - or any low carb diet, whatever name you give it - be a lifetime diet? I've been eating this way for 4 1/2 years and plan to eat this way for the rest of my life.

South Beach is just a low carb diet for people who actually believe sat. fat is bad for you. Nonsense!

and of course if you go off the diet you gain weight. is this a big suprise?

and the low carb diet has been proven again and again and again to be good for your heart - it improves your cholesterol, not the other way 'round.

ah, these myths just won't die, will they?

Sure, you can do it if you want to lead a fairly sedentary lifestyle with not a lot of activity. Not a problem at all.

If you want lots of speed on the bike and do double-centuries fast and win races, that requires a different kind of training regimen and diet.

There's no one "right" way, just pick the path that leads you to the result you want.

the truth lies somewhere in between the two extremes you describe.

From all I've read, at some point beyond an hour or two of pushing yourself really hard, carbs can make a difference.

But of course, you can have a very active lifestyle and never indulge in that level of effort. If so, you can skip the carbs and live a long healthy life.

I agree there is no right way, just a hell of a lot of misinformation regarding low carb diets.

any of you low carbers still alive? any of you non low carbers kick a low carbers ass????

LOL sorry, a lot of time has passed, and here i am.... still trying to figure out how to drop some extra pounds...

you know, i am starting to think that some of us were simply ment to eat.... :)

Well, if you're looking to increase muscle mass, the anabolic diet by Mauro DiPasquale is the real king of the "diets."

However, it's not something most cyclists want. Mst cyclist want to be as light as possible, which means skinny and no muscle mass. Makes a big differencein how you eat.

I am a carb cycler when in season and an anabolic dieter off season. Keeps me with lots of sex muscles - I do not want to look like an emaciated cyclist.

I can't believe you revived this flaming thread:p

In theory, I guess I'm a Paleo guy, but I have no discipline to reduce carbs :) -- I just try to get them from low glycaemic sources.

I have since bought Colpo's book -- it's fantastic. It's now available on ebook for $10

http://www.thegreatcholesterolcon.com/

What is a sex muscle?

Ummm, can someone get this person an anatomy class, stat? :D

(actually I meant to add a y on the end of that)

Starting to see it my way? ;)