Measuring Your Progress BMI VS Weight VS Waist Size VS Photos

Measuring Your Progress BMI VS Weight VS Waist Size VS Photos

Measuring Your Progress BMI VS Weight VS Waist Size VS Photos

I often get asked by BBG Girls what is the best way to track their progress. I understand how confusing it can be, especially with so many different methods to assess your weight loss or fitness progress. It’s really easy to get confused and lose perspective on how to measure your progress!

Previously, I’ve written about some other ways to measure your fitness progress that don’t involve stepping on the scales. But if you get satisfaction or motivation from measuring results and seeing how far you’ve come, this post is for you!

Today I’m going to break down some of the most popular ways you can measure progress, as well as the pros and cons of each method.

BMI stands for Body Mass Index, which is defined as a formula used to estimate your body fat in proportion with your height. Once calculated, your BMI is compared to a table to help determine your weight range (underweight, normal weight, overweight or obese). A BMI between 18.5 to 25 is generally considered to be within the healthy weight range.

How do you do it?
To calculate your BMI, simply divide your weight (in kgs) by your height in m2 (that is, your height multiplied by your height). For example: a person who is 65kg and 1.64m tall would calculate their BMI as follows: 65 / (1.64x1.64) = 24.16. This person would fall just inside the healthy weight range for their height.

For my girls using imperial measurements, the formula is slightly different. Weight (in lbs) x 703/ height (in inches)2.


  • Used by most doctors as a screening tool to estimate body fat as a proportion of overall body weight.
  • Can be used with other test methods. 
  • Comparison is done using a table, so it’s easy to see if your weight falls into a healthy range.
  • Even though the formula is a health standard in many countries, it doesn’t actually have any account for body composition ( % of fat, muscle, water and bone in the body), it is actually a representation how much weight you have per unit of height in your body. Controversially, as a result of this it is often extremely inaccurate for people such as;
  • Adolescents under the age of 18
  • Athletes with high muscle mass
  • Pregnant or breastfeeding women. 
Measuring your weight with a set of scales is an easy way to track your progress at home, but it does have its flaws. A basic set of bathroom scales can’t determine whether you have actually lost fat or overall mass (which may include water).

How do you do it?
Hop on the scales and take note of the weight reading. I suggest that you weigh yourself first thing in the morning, once every four weeks. When weighing yourself, try to be consistent each month with what you’re wearing and the time of day. Also try to use the same set of scales every time you weigh in. This way, you’re comparing apples with apples.

  • Simple to do in the privacy of your own home.
  • No formulas or charts to look up. 
  • Scales are relatively inexpensive to purchase.
  • Daily fluctuations in weight are normal, making it hard to get an accurate reading on your progress. 
  • Gives you an overall weight figure, so it can be difficult to determine if you’ve lost fat but gained muscle.
  • An increase in weight (as a result of muscle gained) can affect your motivation. 
  • They aren’t effective in SHOWING you how your body has changed, which for most people is a huge reason why they begin to exercise
Sweat With Kayla
Waist size
Measuring your waist size can help estimate the amount of visceral fat, or the fat distribution within your torso. Many health professionals use a combination of BMI and waist size to determine whether their patient fits in the healthy weight range.

As a general indicator, the theory says your waist should be less than half of your height measurement. So, someone that is 170cm tall should have a waist size smaller than 85cm.

How do you do it?
Grab a tape measure and measure around your waist. Hold the tape halfway between your lowest rib and the top of your hip bone (this should be roughly where your belly button is). The measuring tape should be firm, but not pinching the skin. Measuring this once every 4-6 weeks is usually a good frequency.

  • Helpful if you’ve lost fat but gained muscle - muscle takes up less space than fat, so measurements can indicate changes the scales can’t. 
  • Easy to measure at home, no expensive equipment needed. 
  • Can be a good indicator for disease risk and general health.
  • Hormonal fluctuations can provide inaccurate readings.
  • Waist can be the last place to change, as this is (statistically) the place most women store fat. 
  • Can be less accurate for people with medical conditions, or for women who have had children.
  • Can’t accommodate for bloating.
Progress Photos
In my Sweat With Kayla app, I recommend taking full-body progress photos every four weeks. Progress photos can help show visible changes, which don’t always translate on the scales! Photos can also be a great motivator, keeping you on track to achieve your fitness goals. As the saying goes, a picture is worth a thousand words. I also need to add, this is by far my FAVOURITE way of keeping track of progress. You can be surprised just how many small changes occur in your body, that you miss because you see yourself daily in a mirror. This is especially a good way to measure change for those people who haven't seen a shift in the scales - a photo can prove just how far you have come.

How do you do it?
Take a before photo when starting Sweat with Kayla or any fitness program, then set a reminder to take follow-up photos every four weeks. For easy comparison, take the photo in the same place, at the same time of day and in the same pose.

  • Easy to take the photos in the comfort of your own home. 
  • No need to record figures or measurements, but can be used with other forms of measurement. 
  • Useful for tracking changes in those with a moderate/light starting weight. 
  • Great way to compare changes over your fitness journey.
  • You can’t clearly measure the results; it’s a comparison only. 
  • Changes in your pose or the lighting can have a big impact on the appearance in the photo. 
To be honest though, it’s best not to get too caught up with measurements or weight, particularly if you’re just starting a new fitness routine. It’s good to look at what you’ve gained too; like strength, fitness and a positive outlook. Focusing on how you feel, rather than what you weigh, is a great way to stay motivated to reach your goals as well!

Love, Kayla xx

* Results may vary. Strict adherence to the nutrition and exercise guide are required for best results.