Scales Lie: 7 Ways the Scale Lies to You About Your ProgressMay 13, 2021
Scales lie. That's just the way it is. What should be an objective metric is often inaccurate, difficult to decipher, and not directly correlated with your progress.
In general, the scale is probably my least favorite tool to track progress.
BUT, I do think it has its place when used appropriately.
What do I mean by "appropriately?"
Well, first of all, if you’re ONLY using the scale to track your progress and dictate the changes you make, you’re doing yourself a HUGE disservice.
If your goal is to change your body composition in any way (lose body fat and/or build muscle), the scale should NOT be used alone.
I repeat...DO NOT USE THE SCALE ALONE!
You must combine the data you get from the scale with other tracking metrics such as body tape measurements, progress pictures, how your clothes are fitting, how you feel, etc., or else you won’t be getting the full picture of what’s actually changing with your body composition.
Additionally, if you get caught up in what the scale shows on a day-to-day basis, you’re going to drive yourself absolutely CRAZY...for NO reason!
There are SO many different factors that impact the number that shows up on the scale in a 24-hour, 48-hour, or even week-long timeframe.
How the Scale Lies to You
Here’s what the day-to-day scale number actually reflects:
1. Hydration status and electrolyte balance.
Electrolytes (magnesium, potassium, and especially sodium) control water balance and cell hydration. When electrolyte levels become too low or too high, they can cause shifts in fluid balance which can lead to increased or decreased water weight.
Did you go out to dinner last night at your favorite Mexican restaurant and wake up the next morning 3 pounds heavier? Guess what, you didn't gain 3 pounds of fat overnight (impossible)...you just consumed a lot more sodium than you're used to and your body is retaining extra water.
2. Food residue in the gut.
Fun fact: Food residue, or the undigested food moving from the gut through the colon before excretion can actually make up 3-7 pounds depending on what you ate (high-fiber foods tend to produce more food residue).
That big ass salad you ate last night with extra broccoli and cauliflower on the side is still hanging around this morning and causing you to freak out during your morning weigh-in (eye-roll).
3. Your frequency of bowel movements.
Anybody else weigh themselves, take a poop, and lose 2 pounds...just me? Psh, doubt it.
4. Carbohydrate intake (reflected in glycogen storage).
Glycogen (the storage form of glucose, AKA what carbs get converted to in your body) can make up around 5-10% of the weight of your liver, and 2% of the weight of your muscles.
For every one gram of carbohydrate stored in the body (as glycogen), there is approximately 3-4 grams of water retained.
Eating lower carb during the work week and decided to indulge in a slice of pizza with your fam on Friday night? Yeah, you bet the scale jumped up Saturday morning...IT'S JUST WATER!
5. Whether you worked out or not.
Working out can cause you to both lose and/or retain water which can of course tip the scale in opposite directions at different times.
When you work out and sweat, you will lose water and electrolytes. Depending on how much you sweat, the scale can drop significantly.
When you resistance train, you put stress on your muscle fibers which causes small micro-tears and inflammation (this is how muscles grow: break ‘em down, build ‘em up) and your body can retain fluid to try and heal those micro-tears.
Personally, I typically always see a jump in the scale the day after I train my lower body because my legs tend to be more inflamed and are holding onto a bit more water. It's a sign I pushed myself in my workout, not gained 2 pounds of fat overnight.
Also, your muscles store glycogen to break down for energy during your workout. If you’re new to resistance training or haven’t trained consistently for a while, you may have an increased amount of carbohydrate and water being stored in your muscles which can lead to a jump up in the scale number for a little while.
As your muscles become more accustomed to the exercise and more efficient, they will need less glycogen to maintain the same level of energy output, and therefore you start to lose the initial water retention (usually within a few weeks).
Takeaway: If you just started lifting weights for the first time in a while, you may see the scale number increase for a week or two. Don't freak out!
6. Your menstrual cycle.
There are two main hormones involved in your cycle -- progesterone and estrogen -- that naturally rise and fall throughout the month.
During the luteal phase (the time between ovulation and before the start of your period or menstruation) progesterone levels rise and progesterone can actually cause you to be less likely to retain water during this time because it blocks the binding of aldosterone to its receptor (aldosterone is a hormone that plays a large role in water retention in the body).
As progesterone drops during the late luteal phase (PMS week), there is actually a rebound effect which can then cause water retention.
Additionally, the surge in estrogen during the follicular phase (the time between the first day of your period and ovulation) can cause a woman’s body to retain more sodium and ultimately cause more water retention.
So, during the late follicular phase (around days 10-14) and the late luteal phase (around days 26-28), you’re more likely to retain water and see the number on the scale rise.
This doesn’t necessarily happen to everyone and some may notice water retention at other times during their cycle due to individual variances.
Additionally, if you are post-menopausal, hormones will still fluctuate at different times and can cause water retention to the same degree.
7. Stress and sleep.
Chronic stress can cause water retention due to the increase in cortisol (primary stress hormone). This occurs because cortisol can partially bind to a receptor known as a mineralocorticoid receptor, which normally binds a hormone that causes water to be retained in the body.
When enough cortisol is present, and for long durations of time, it can bind to this receptor and cause water retention.
Lack of sleep may also affect the sympathetic renal nerves in the kidneys, which regulate sodium and water balance.
For these reasons, high stress and/or lack of sleep can absolutely cause the scale number to rise.
Okay, I think I've made my argument.
The biggest takeaway here is that the hour-to-hour and day-to-day variability of the number on the scale DOES NOT MATTER.
Scales Lie: So Who Should You Trust?
When you use the scale to assess weekly and bi-weekly averages and long-term trends.
Although this is not always the case (Tara’s transformation is a prime example), in general, a downward or upward trend in scale weight over time will correlate with body fat loss or muscle/fat gain.
Tracking weekly and monthly averages can be helpful for assessing changes if done correctly AND in combination with other metrics such as:
- weekly body tape measurements
- monthly progress pictures
- performance increases during training (i.e., getting stronger)
- how your clothes fit
- how you feel
Ideally, if you’re going to weigh yourself, you want to do it a minimum of four times per week, at the same time each day (although every day would be the most accurate for getting a 7-day rolling average).
This approach allows you to bypass daily fluctuations while still creating a trend line that’s either flat, downward, or upward representing no change, or a true loss or gain over time.
Main Takeaway: Short-term changes in body weight are practically meaningless while longer-term changes tend to represent more accurate progress. Don’t let the day-to-day scale fluctuations get to your head - they DO NOT MATTER!
How To Use the Scale Appropriately
- Weigh yourself at least 4x/week (ideally every day so you can truly get an accurate weekly average).
- Weigh yourself first thing in the morning, before eating or drinking, after using the restroom, nude.
- Make sure your scale is on a flat, hard surface (not a rug or carpet).
- Weigh in using the same scale. DO NOT alternate between your home and gym scales, for example, because it will lead to inconsistent readings - all scales are calibrated slightly differently.
- Remind yourself that it doesn’t matter at all what you weighed today, this is just data you are using to track trends over time!
Scales lie—but we don't. If you need further help and/or guidance to reach your body composition goals, check out my Nutrition and Exercise Programs.
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