[bo1024]

It's not very likely to happen with water either. 6kg of water is 6 liters, which is probably more than the amount of blood in their body. I have to question the measurements on the 6kg fluctuations, going from 60kg to 54kg in a week is serious.

[ddeck]

That's true, but there is a lot of water in the body aside from the blood.

While most people will feel physical effects after losing 5% of their body weight in water, many can lose up to 8-10% without significant adverse physical or mental impact. Loss over 10% is considered serious dehydration.

World champion marathon runner Haile Gebrselassie famously won the Dubai marathon in 2005 with a 10% body weight loss during the race:

https://www.ncbi.nlm.nih.gov/pubmed/22450589

[avinium]

It's pretty common to cut 5-10kg in preparation for wrestling/judo competitions.

A natural 6kg fluctuation isn't inconceivable. I'm fairly sure I could get there starting dehydrated/carb-depleted and pounding a carb-heavy meal with a lot of fluids.

It definitely wouldn't be accidental, though.

[m0zg]

Cutting for competitions involves diuretics though. They literally piss out the weight to end up in their target weight bracket.

[hombre_fatal]

I've fluctuated about that much in 48 hours just going from eating a lot of food constantly -> fasting (no food, no water). Think about all the food and liquid you can pack into your stomach and intestines.

Seems crazy, but try it. I went from like 180lbs to low 160s. Of course, it comes back when you start eating and drinking again.

[_carl_jung]

This isn't what people typically mean when they talk about weight loss, though. Which is why normally you hear recommendations for measuring your weight at the same time every day with an assumption that your eating patterns are roughly constant.

[dragonelite]

This, i find i can lose like around 2.5kg by fasting 2 days 1.5kg is usually water weight and 0.5 kg feels like food mass and the other 0.5kg fat loss. The water and food mass weight will come back once you start eating again.

[jbarberu]

- "I managed to strip 60kg off my race car"

- "Wow, how did you manage that??"

- "I just emptied the gas tank!"

[11235813213455]

I'll try to measure it, it's something like 58-59kg, after a long bike ride the sunday and 64-65kg after eating - I buy 10-12kg of fruits/legumes twice a week - so yes it's 80% water