CommunityBrowse groupsBlogEtiquetteInvite Your friendsSuccess Stories


Confused - Scale Weight Fluctuations - Water Weight?

I'm wondering how much scale weight can fluctuate in 1 hour. I typically do my weigh in every morning AFTER my workout. Well, this morning I decided to do it before my workout as well. Before my workout, I was 143.0 and after I was 141.0. I know I could not have burned 7000 calories - could that be the water weight I sweated out? I'm confused!

Thu. Aug 31, 10:41am

Add comment  
Well, that would be a little less than a quart of water. If you were sweating and not drinking during your workout, it's likely.

Thursday, August 31, 2006, 10:49 AM

Add comment
There could have been many factors contributing to the scale fluctuations. I have found scale measurements taken during the day are not accurate because they can vary based on last BM, last time I ate, how recently I've worked out, how hot it's been....

The best time to weigh yourself for accurate weight measurement is everymore first thing after you wake up and before you eat breakfast. Your weight will probably go up during the day but this is one time that you body is pretty consistant as far as factors that lead to weight gain or loss.

Thursday, August 31, 2006, 10:50 AM

Add comment
OP here...

so is my weight 141 or 143? If I sweated that much, should I be taking a diuretic?

Thursday, August 31, 2006, 11:17 AM

Add comment
a diuretic will only increase the amount of liquid (urine) that your body expels. i would suggest that if your body is losing that much in water weight form just working out, maybe consider drinking more water and less caffeine (a diuretic). regularly running your body with not enough hydration will eventually take its toll-your body loses potassium and magnesium quickly when depleted of bodily fluids. this can cause respiratory and nervous-system abnomalities.

Thursday, August 31, 2006, 11:27 AM

Add comment
Weight will fluctuate as much as 5lbs during the day

Your weight will fluctuate as much as 5 lbs during the day. It has something to do with water but also how your body functions.

DO NOT weigh yourself before and after working out -- that is a recipe for disaster. The only folks that I have ever known to do this were anorexic, bulimic or both.

Your goal is to be healthy. Weighing twice a week is a more accurate picture of your true loss. Weight watchers and most official trainers only mark you weight once a week to avoid the fluctuations.

DON'T TAKE A DIURETIC! My mother did this while exercising and had a massive stroke and lost most of her ability for cognitive functioning.

While they are over the counter, they are dangerous!

Thursday, August 31, 2006, 11:29 AM

Add comment
DON'T TAKE A DIURETIC -- REMEMBER Terry Schiavo? She took Diuretics while exercising


Do you remember Terry Schiavo? She took diurectics while exercising to lose a few pounds and wound up with a massive stroke and a vegetable for 15 years before they took her feeding tubes out!

Talk about a recipe for disaster. This is not a joke, your life is worth more!

Thursday, August 31, 2006, 11:31 AM

Add comment
To the 11:27, I am the OP

I dont' drink any caffeine at all - no soda, water or tea, never did the caffeine thing, so it is not like I miss it. I drink on average 64oz of water per day, sometimes more. Should I increase that?

Thursday, August 31, 2006, 11:51 AM

Add comment
i highly recommend getting your blood checked for your electrolyte, potassium, and magnesium levels. i have suffered from dehydration a few times because of poor dietary choices and exercising routines and a couple of times i even had to go to the emergency room for potassium to be given intraveneously-the absolute most uncomfortable, burning, irritating sensation i can think of. they have to ice down your forearm the ebtire time that the potassium is going in and it is a slow process because of the danger of administering too much too fast. i now get regular blood tests to ensure that this does not happen again. i also sweat what seems to be like an inordinate amount when i work out (or even when i am slightly active in a hot environment), and drink water throughout the day, not really paying attention to the total consumption daily. i just always have a bottle of water in my hand and drink it all the time. if i ever go out for a cocktail, i drink mega amounts of water with, between and after each drink. and i drink a lot of water during my exercising routines. it is vital to stay properly hydrated!

here's one link:


Thursday, August 31, 2006, 12:07 PM

Add comment
Yes you should drink more water. 64 oz is the average if you are of average weight and are performing mild levels of activity... more activity (meaning you're losing more water) means that you need to drink more water to replenish what you've lost!

Thursday, August 31, 2006, 12:25 PM

Add comment
Medically significant dehydration is mostly limited to extreme behaviors or extreme activities (or, of course, illness). 2 pounds is not medically significant unless you were already in trouble before you started.
There's water loss via breathing, as well as sweating. Breathing harder, and mouth breathing more, (both typical of workouts) both increase the rate of water loss somewhat.
64 oz in a day would serve most people adequately for something like an office job with a moderate workout session. If you are hiking in the desert sun, or running long distances, for example, you likely need twice as much. People who are doing those sorts of activities should be trying to pre-load somewhat, as well as take in more as you go.
I have lost 3 lb in a 3 mile run in very hot weather. That's essentially all water. The most weight loss I ever had in a day was 10 lb (backpacking with heavy pack in mountains in hot weather). I took precautions ahead of time for that. (That was 10 out of about 175, which doesn't count the pack. The pack was heavy because I was carrying my own and other people's water!) I knew it was going to be a whopper which is why I weighed before and after, to get an idea of what it was doing to me.

Thursday, August 31, 2006, 12:34 PM

Add comment
I hike a lot in desert conditions and drink about 2 gallons/day while doing so. (That's over 16 lbs of water.) Of course not all of that is eliminated through sweating -- the point is to keep one's kidneys working!

That's an extreme case, however. It's worth noting (there was a NYT article about this a while back) that while death from dehydration does not occur among race runners -- I think it was marathon race data they were looking at -- deaths from OVERhydration occur every year. It IS possible to drink too much, and apparently that's more difficult to diagnose and treat.

Thursday, August 31, 2006, 1:08 PM

Add comment
Losing 2 pounds across a workout is totally normal. And unless you were dehydrated beforehand, or don't drink anything afterwards, you are not at risk for dehydration.

A while back, I was weighing myself before and after every workout (just for personal info, and no, I am not anorexic or bulemic or often you should weigh yourself varies widely between people), and the amount I would lose across a workout varied from 1 pound on an easy work out to 3 or even 4 on a long, hard workout.

Thursday, August 31, 2006, 6:34 PM

Add comment
Confused - Scale Weight Fluctuations - Water Weight?

weighing yourself before and after workout can tell you how much your are sweating out is true. also true that you can drown yourself from the inside by drinking too much water. suggestion if you are sweating out too much from hot weather/intense workout is to use sports drinks because they contain the proper electrolytes/salt your body needs. here's a website about hydration suggested by the complete book of beginning running:

Thursday, August 31, 2006, 8:54 PM

Add comment
Weighing pre- and post-workout (and at other times)

1. Some books and articles on running actually suggest pre- and post- workout weighing. This activity can help someone figure out the right amount of water to drink. This is not an aneorexic thing or a how-much-do-I-really-weigh thing, but a how-much-water-do-I-need-while-exercising thing

2. On the "Doctor Weighs In" column, there are have been a couple of articles recently on the benefits of daily weighing. In one ( - only room for one link below), daily weighers were found to be almost twice as likely as non-daily weighers to successfully maintain weight loss. There was another article recently (although could not find the link) that spoke of recent studies indicating that daily weighing is more helpful than previous thought. I am not actually advocating daily weighing. It is not the right choice for everyone and not recommended by all programs. However, I do want to point out that if someone wanted to weigh him or herself every day, that is not a wacko idea but quite in line with some recent research.


Thursday, August 31, 2006, 10:16 PM

Add comment
water weight fluctuation

We pay a lot of attention to this, but does this even matter long term? Does the retention of water have any indication of how healthy I am?

Tuesday, April 24, 2007, 7:24 AM

Add comment
Have you tried stepping off and back onto your scale? Mine will give me 1 - 2 lb fluctuations with multiple weighings. Seems to matter exactly where I put my feet, the way I lean, and whatever else. Before getting freaked out by a small change in the weight, check out the accuracy and precision (reproducibility) of your scale.

Tuesday, April 24, 2007, 8:41 AM

Add comment

Related Content:

How To Lose Weight- The Basics
Weight Watchers Points System
The Fat Smash Diet
The Eat To Live Diet
The Beck Diet Solution
How To Get The Motivation To Lose Weight


How To Be Successful Using PEERtrainer

How To Burn Fat
Online Weight Loss Support- How It Works
Does Green Tea Help You Lose Weight?
Tips On Using PEERtrainer
Visit The PEERtrainer Community
Diet and Fitness Resources


Weight Watchers Meetings
Learning To Inspire Others: You Already Are
Writing Down Your Daily Workouts
Spending Money On A Personal Trainer?
How I Became A Marathon Runner


Preventive Health

How To Prevent Injuries During Your Workout
Flu Season: Should You Take The Flu Shot?
Are You Really Ready To Start PEERtrainer?
Super Foods That Can Boost Your Energy
Reversing Disease Through Nutrition

New Diet and Fitness Articles:

Weight Watchers Points Plus
How To Adjust Your Body To Exercise
New: Weight Watchers Momentum Program
New: PEERtrainer Blog Archive
Review Of The New Weight Watchers Momentum Program

Weight Loss Motivation by Joshua Wayne:

Why Simple Goal Setting Is Not Enough
How To Delay Short Term Gratification
How To Stay Motivated
How To Exercise With A Busy Schedule

Real World Nutrition and Fitness Questions

Can Weight Lifting Help You Lose Weight?
Are Protein Drinks Safe?
Nutrition As Medicine?

Everyday Weight Loss Tips

How To Eat Healthy At A Party
How To Eat Out And Still Lose Weight
The Three Bite Rule
Tips On How To Stop A Binge