Working out is healthy. That’s a good starting point but, after that, things start to get complicated. What are healthy weight goals? Is there such a thing as unhealthy muscle goals? Where do you even start?
The first step to choosing a healthy weight goal is understanding how weight is measured. It’s a bit more complicated than you might think.
You’ve probably heard of “BMI,” or “Body Mass Index,” even if you aren’t sure what it means or how it works.
A person’s BMI is essentially a ratio of their height and weight. It is determined by dividing your body mass in kilograms by the square of your height in meters. If you don’t want to deal with all that math, calculators are also freely available.
Once you have your BMI, the number falls into one of four categories: below 18.5 is “underweight,” 18.5 to 24.9 is “normal,” 25 to 29.9 is “overweight,” and over 30 is “obese.”
The great thing about BMI is that it makes everything sound so simple, which is why it’s commonly used in healthcare. For the average person, that’s just fine. However, people like athletes and bodybuilders run into a problem.
Muscle is more dense than fat, but BMI doesn’t account for where weight is coming from – it just compares height and weight. That means that if you have a high muscle mass but a low percentage of your weight is from fat, your BMI will still say that you’re overweight or obese.
So, if your weight goals involve losing weight from fat without necessarily building muscle, BMI is great. If you’re trying to gain mass by building muscle, BMI doesn’t tell you much.
If your weight goals involve gain from muscle mass, it can be hard to determine how much of your gain is actually from muscle. While methods exist, they are more complicated.
One method involves taking measurements of height, weight, skinfolds, bone-breadth measurements, and the circumference of some limbs (Abernathy et al., p. 53).
While you probably won’t be able to manage these measurements on your own, a personal trainer at your local gym or fitness center may be able to help you.
Another option is to use a “body fat scale.” These tools are able to measure your body weight minus your body fat. They’re more expensive than a typical bathroom scale and they aren’t as accurate as the other methods described here, but they’re the most affordable and accessible option.
Keep in mind as well that these scales won’t give you your muscle mass, they give you your lean weight. That includes muscle but also includes other non-fatty tissues like your bones.
Diagnostic Imaging Techniques
Computer Topography and Magnetic Resonance Imaging can both tell tissues apart allowing more exact studies of muscle mass (ibid, p. 52).
You won’t be able to go to your local hospital and ask for these kinds of tests, and you probably won’t have access to them at your gym or fitness center. However, if you have a research university near you that has active kinesiology or med and pre-med programs, you might be able to access these tests by working with professors and other university researchers.
Healthy weight loss goals
If your weight goals involve losing weight, you can run BMI backwards to determine a healthy weight goal. Set your desired BMI and remember that your height is a constant, then solve for your desired weight.
Or, better yet, talk to your healthcare provider about your weight goal. This is particularly important if you have medical complications or if you are older.
Once you have your ideal weight goal, you may want to drop that weight as fast as possible. However, while excess body weight is bad for you, losing it too quickly – or trying to lose it too quickly – can also be bad for you.
Unless your weight is an immediate threat to your health, trying to lose more than around two pounds per week isn’t recommended. Losing more than that through diet and exercise alone is difficult. Further, it tends to be unsustainable in the long-term.
Healthy Weight Gain goals
As mentioned above, BMI isn’t a particularly helpful tool when it comes to determining healthy weight from muscle. A more helpful gauge is “Muscle Mass Percentage.” This number is the percentage of your body weight made up of muscle.
The average muscle mass percentage for someone age 18 – 35 is 40 – 44 for men, and 31 – 33 for women, but there’s definitely some room to build on that – though upper safe limits haven’t really been established.
Interestingly enough, the amount of muscle mass that the average person can gain in a week is about that same two pounds.
Trying to gain weight faster than this, in addition to being unsustainable for most people, might push you to work harder than is safe. That can lead to bone and muscle damage.
Focusing too much on muscle gain can also distract you from other forms of exercise. The exercises that are the best for building muscle aren’t the best for lung and heart health or for balance and flexibility. That means that for holistic wellness, building muscle shouldn’t be your only goal.
Start working out!
You can figure out your weight goals by using BMI, muscle mass percentage, or another metric depending on your personal goals and the resources that you have access to.
When it comes to chasing weight goals in a healthy way, it all comes to a balance of pushing yourself without pushing yourself too hard. If you’re worried about how much is too much, work with a trainer or a care provider to determine what’s right for you.
One thing is for certain – fear of gaining weight from muscle or losing weight from fat too quickly shouldn’t deter you from working out. Few people manage weight change that is fast enough to be unhealthy. So, keep an open eye but don’t be afraid to try your best.
Abernathy, Bruce; Kippers, Vaughan; Hanrahan, Stephanie J; Pandy, Marcus G; McManus, Alison M; Mackinnon, Laurel. “Biophysical Foundations of Human Movement.” 3rd ed. Human Kinetics. Champaign, IL. 2013.