If you've ever tracked your body weight on a consistent basis you've likely come across times where the scale either sticks or fluctuates. If this is your only mode for measuring progress then it can become extremely frustrating and derailing. In this article I'll explain why your body weight is doing what it is.
I will preface this entire article by saying that using a scale as your only measurement tool is not suggested. I use skin fold calipering as an additional resource for body composition trend data, but realize that not everyone has access to a trainer. Another tool that I use that you can do to yourself would be circumference measurements. Using a Tape Measure can give you additional insight as to whats really happening to your body composition. I would suggest measuring around your bicep, navel and leg (make sure to use the same arm and leg each time). For males, I will also recommend measuring their chest and for females their glutes. Oftentimes you'll notice that your circumference measurements will continue to decrease despite a body weight plateau. First, lets go over weight fluctuation. Some of my clients become concerned over the difference between their morning weight and mid-day or evening weight. Assuming that your calories are consistent, this doesn't matter. You're not gaining fat during the day. The scale is simply reflecting your hydration and food intake. I highly suggest keeping your weigh in times the same each day and in the same clothing (preferably none). The most consistent time would be right after you wake up and use the restroom but before eating.
Another reason for scale fluctuation is water intake. Monitor how much fluid you intake daily (all sources considered) and make sure you write it down. Obviously any variation in the amount of fluid you intake could affect the number on the scale. Also, you may be retaining either more or less fluid due to electrolyte intake. Do you track your sodium and potassium intake? You should! A consistent daily range for sodium and potassium will not only help with scale consistency but optimal performance. Ok, now that you're doing everything you can to eliminate fluctuation why is the scale at a plateau? Again, this is multi-faceted. It should first be stated that if you aren't tracking your caloric intake, get on it! Its really hard to know where you could be going wrong without calorie data. Most likely you're eating more calories than you think, or just enough to keep you in a maintenance. If you have been tracking calories/macros then start with a reevaluation of your intake. Do you track everything you eat? What about little snacks or cooking oil/spray? Even small snacks can add up and keep you at the same body weight.
Once you're 100% sure that you have your calories perfected, lets look at your burn. Are you doing the same old workout plan that you found off the internet 6 months ago? Has it changed at all? Or is it the same sets and reps and exercises as when you started? As we repeatedly do the same motions our bodies become more adapted. Thus, we'll burn fewer calories doing the same movements as before. I would highly suggest implementing a training program that will keep you from having adaptive plateau's. What about the rest of your day? What do you do for work? Has the amount of required movement changed at work? Oftentimes we'll subconsciously move less when we're in a calorie deficit. Even the amount of fidgeting we do can be measurably less when in a calorie deficit. Thus, our daily calorie burn decreases and can lead to a weight loss plateau. In order to overcome this, I recommend that my clients track their daily steps. Monitoring steps is an easy way to make sure that our non-exercise caloric burn is staying similar.
What about muscle gain? Its completely plausible for us (especially new lifters) to gain muscle at the same rate as we're are losing fat. If the scale is our only tool for gauging progress then it would leave us feeling like we arent progressing. But, muscle tissue is less dense than fat tissue so using circumference measurements would allow us to see that we are getting smaller around even though the scale is the same.
Another consideration for women would be their menstrual cycle. It is very common to see fluid retention starting the week before and continuing through the week of your period. These are all normal fluctuations and shouldn't be taken to heart or as a determination of your progress.
The weight we see on the scale is just one small piece of the puzzle. Its a tool that helps us to see trends but overall carries only a small significance to our progress. I have repeatedly seen clients dramatically reduce their circumference measurements and appear leaner without the scale moving at all! Just remember that we all have a history with the scale, and maybe that's a reason for us to stop weighing at all. Ask yourself, would you care how much you weighed if you looked how you wanted to in the mirror?