How much weight can a grown man lose in 12 days?

[Nelso]

you could actually comfortably loose up to 8kg

Not of fat he couldn't. If you did loose more than 2 or 3kg it will be a reduction of glycogen and water storage in the muscle. Stick to losing your 1 to 2kg per week as it will give you a longer lasting result.

Wouldn't that depend entirely on the exercise and diet he employs during this 12 day period. That's a very firm, "no way". You have little idea what the body is actually capable of if put under the right stresses and conditions.

I have lost 5kg in under 10hrs on a race day! And before you go saying it was all fluid, it wasn't! I weighed in pre race, over hydrated on purpose to get a falsely high reading, and still weighed in 5kgs under my normal weight, or 8kg's under my weigh in weight, at the end of the race.

8kg's is definitely do able under the right conditions.

I spent the time to write out a big explanation as to why it is impossible to lose that much fat in a short time but I accidentally hit the wrong button and it disappeared and I couldn't be bothered writing it all again. I have a degree in this stuff including the study of exercise physiology so believe me when I tell you it is NOT fat that you are losing when you lose weight fast. If I get the energy tomorrow I may elaborate why, but at the moment I feel like throwing the computer across the room.

[Stereo]

I will keep a diary in here outlining exactly what i ate and what excersize was done.... Lets discuss afterwards what I did wrong and right...

The trick will be a drastic cut down in the carbs and sat-fats that I tend to eat when I am snacking... Also cutting out the empty calories of alcohol is going to make a big difference. Add to that 30-40 mins of decent cardio a day, lots of drinking water... and I dont see how I can go wrong

On top of that will be the intake of 2 additonal "snack" meals during the day (making a total of 6 meals a day) to keep the metabolism up.

After all, no matter what diet you look at (barring aitkens) it all comes down to consuming less calories that you expend.... just makes sense doesnt it?

[csgup1]

when you go from not exercising and eating crap to exercising and eating well you lose a fair amount of weight in the first few days before it tapers of to about 1 kg a week.

just keep at it and you will notice a huge difference even in the first month.

the trick is to eat 6 ish small meals a day not huge ones and stay off the carbs at night.

[triway]

I spent the time to write out a big explanation as to why it is impossible to lose that much fat in a short time but I accidentally hit the wrong button and it disappeared and I couldn't be bothered writing it all again. I have a degree in this stuff including the study of exercise physiology so believe me when I tell you it is NOT fat that you are losing when you lose weight fast. If I get the energy tomorrow I may elaborate why, but at the moment I feel like throwing the computer across the room.

Please take the time to do it again. I am interested in how your theory says that I can't do what I have already done...........

[Nelso]

Ok. There is a big difference between losing weight and losing body fat. Your body utilises three main energy systems: phosphates, glycolitic and aerobic. The first two use glucose which is broken down from carbs and the third burns fat. In order to burn fat you need an adequate supply of oxygen and when work loads increase beyond what your cardiorespiratory system can supply it relies on the other two energy supplies. So that you have an abundant supply of glucose your body stores glycogen in your liver and muscles. Glycogen also allows fluid to be retained in the muscle. When you decrease the intake of carbohydrates your glycogen stores diminish and along with that so does the water retention in your muscles. If your intake drops bellow a level that will sustain your bodies homeostasis your body goes into a ketonic state and will look to break down muscle tissue as well. There is a point of diminishing returns for fat loss with restricting nutrients and/or increasing work output. Once that point is reached your body will not break down your adipose tissue (fat stores) any faster and will look for other sources of energy.

The majority of fast weight loss is the loss of glycogen stores and with that, the reduction in water retention (there is more to being hydrated that just drinking plenty of water. Diet and the body's chemistry play a major roll in hydration). Granted there will be some fat loss but there is also likely to be muscle loss as well so even though you can lose up to 10kg in a 24 hour period my point still remains that it will not be 10kg of fat loss. It is physiologically impossible for your body to convert that much adipose tissue in that short length of time.

[jonoZRX]

Good post Nelso.

[mike-s]

Here i was thinking of "as quick as you can sign the divorce papers"

[triway]

Ok. There is a big difference between losing weight and losing body fat. Your body utilises three main energy systems: phosphates, glycolitic and aerobic. The first two use glucose which is broken down from carbs and the third burns fat. In order to burn fat you need an adequate supply of oxygen and when work loads increase beyond what your cardiorespiratory system can supply it relies on the other two energy supplies. So that you have an abundant supply of glucose your body stores glycogen in your liver and muscles. Glycogen also allows fluid to be retained in the muscle. When you decrease the intake of carbohydrates your glycogen stores diminish and along with that so does the water retention in your muscles. If your intake drops bellow a level that will sustain your bodies homeostasis your body goes into a ketonic state and will look to break down muscle tissue as well. There is a point of diminishing returns for fat loss with restricting nutrients and/or increasing work output. Once that point is reached your body will not break down your adipose tissue (fat stores) any faster and will look for other sources of energy.

The majority of fast weight loss is the loss of glycogen stores and with that, the reduction in water retention (there is more to being hydrated that just drinking plenty of water. Diet and the body's chemistry play a major roll in hydration). Granted there will be some fat loss but there is also likely to be muscle loss as well

Couple of assumptions being made there. First, you assume that everyone burns fat at the same rate, and under the same conditions. Obviously not true, as two people can eat and train identically and have different amounts of fat burning. Everyone is different.
Second, you neglect the fact that you can train your body to burn fat more efficiently, again, this will result in different people with the same stimulous, seeing different results of fat loss.

...so even though you can lose up to 10kg in a 24 hour period my point still remains that it will not be 10kg of fat loss. It is physiologically impossible for your body to convert that much adipose tissue in that short length of time.

So according to your 'book', how much fat can an individual convert in a day? Hang on. That would depend entirely on the individual and the exercise being performed wouldn't it?
I am constantly amazed by blanket statements relating to fat loss and exercise, with so much diversity in body composition, fitness levels and metabolism, there can be no statement that will be true for ALL people.
Physiologically impossible? Impossible for who? Lard ass who watches TV all day, or an athlete training 40hr/week in their fat burning zone?

'Impossible' is just 'possible' with a prefix!

[triway]

I am interested in seeing your DEXA scan results which show your entire weight loss was fat. I'm not sure why you think that your story proves the weight loss was not water weight

Just as I'm not sure why you think, without knowing anything about my body, it's composition, or it's training, that it could not have been?

[Nelso]

triway, the fastest way to lose body fat is to take growth hormones and testosterone along with your diet specifically calculated for your body and the ideal amount of exercise. With all of these factors hitting the sweet spot the most body fat you will convert is still less than 5kg per week. If it was possible to do it better professional body builders (arguably the best crash dieters in the world) would not spend such a long time torturing themselves preparing for a competition (and they are not scared to manipulate their body chemistry to improve how fast they can achieve these things). If you know of a way to lose fat faster than the human body is capable of I suggest you patent it as you will make more money than Bill Gates.

You don't seem to acknowledge what I am saying about limiting calories or carbohydrates and the effect it has on glycogen stores and how much that manipulates body weight. You can increase or decrease carb intake by as little as 10% to manipulate glycogen storage so your body weight can fluctuate quite a bit without your body fat even changing at all. Once you combine fat and muscle loss with this you will get a more significant weight change.

The fat that is lost will always be just a fraction of your total weight loss as your body will absorb muscle, connective tissue and bone to preserve energy as well as fat. If there is not the adequate supply of nutrients to store (if you are losing weight there isn't) you will lose weight due to less glycogen and water retention as well. The other thing to remember is it take time for your body to adapt to things. It can't produce the amount of antibodies to fight off infections instantly, it takes days to produce enough. If you want to get stronger it takes months of training, if you have surgery it takes months to recover and if you want to resorb fat it takes time as well. This is not a 'book' saying this, it is just the way the body works.

You still haven't told us how you can be sure it was all fat loss that caused your 8kg weight reduction in one day or are you just assuming it was because you drank plenty of water?

As for impossible. I'd like to see you chop your left arm off and grow another one. I would say for you at this point in time it is impossible.

[triway]

I'm gonna leave it there.

You guys can believe what your degree has taught you, I will believe what I believe from experience.

Cheers

[Six Addict]

all this arguing over losing "weight" and losing "fat"

im sure you did lose 8kg, tho im also doubtfull as to whether is was all fat... but please dont let this open another can of worms...

its hard to argue against actual experience, but its also hard to argue well understood, reasoned science....

i declare a draw!!!

[Dizzi]

Just for the record, I didn't say I lost 7kg of fat, I said I had lost 7kg and it could be done, I'm not going to argue my point of what I know or don't know, all I am saying is I did losse the weight and yes I did keep it off and managed to loose more over weeks to come and keep it all off when I was dancing for many, many, many years. All I stated was that you could loose that amount of weight over 12 days, especially if you train really hard and rediculously discipline yourself with food.

[tim]

Update Stereo?

[Nelso]

I like how people assume if you have the scientific knowledge you must lack experience. I personally won national titles in Powerlifting holding a heap of national records long before I did my degree and have personally trained many elite athletes over the years and had plenty of others as friends. When you sit down with a fully sponsored professional body builder and discuss their drug program frankly with them or the strength and conditioning coach of Olympic teams you get a fair idea of how the scientific research relates to real world situations. I'm sorry if I offended anyone with what I wrote as that wasn't my intention, nor was it to try and big note myself. Honestly, I was just a bit surprised at some of the figures people were throwing out there and then was asked to explain why I thought that way.