How do I know if I am gaining fat or muscle?

Being consistent with your measurements is a great way to know if your gaining fat or muscle. Muscle is more dense than fat. Meaning one pound of muscle will take up much less space than one pound of fat. If after three to four weeks on your program you begin to notice your weight going up and your body fat measurements staying the same or decreasing, it is likely you are gaining muscle. Another good indication is how your clothes fit. Again, if the scale shows your body weight increasing, yet your clothing is still fitting the same or maybe even fitting better, you are probably gaining muscle and not fat.
The best way to know if you are gaining muscle or fat is to track your body fat percentage by using calipers or a hand held body fat/bmi monitor. Check yourself every week or two, if your body fat % is dropping, you are gaining muscle, if the fat % is going up your are gaining fat. Another easy way is to take your body measurements regularly, if you are gaining weight according to the scale, but you are loosing inches, you are gaining muscle and loosing fat. Muscle takes up less space than fat. If the scale says you are gaining weight, but your clothes fit looser and you look thinner, you are gaining muscle and loosing fat.
The best way to tell if you are gaining fat or muscle is to have your body fat percentage measured.  This way you know for sure.  Always have the same person measure you and wear similar clothing each time to make the measurements more consistant.  Muscle does weigh more than fat, so if you are not getting measured regularly then you may be able to find signs.  If the scale is not changing but your clothes are fitting better, this would indicate muscle gain.
Well the best way to measure if you are gain fat or muscle is to get your bodyfat test by a fitness professional.  As sometimes increase in weight is not so bad.  Simply you can lose 5 pounds of fat and gain 5 pounds of muscle and still weight the same but you will look skinnier.  So common methods of testing your body fat is skin calipers, bioelectrical impedence or under water weighing.

You can utilize body-compostion statistics for providing information about fat or muscle gain/loss. Body fat can be measured by the following methods:

Skin-Fold Caliper measure a client's amount of subcutaneous fat (or fat beneath the skin) by calculating the size of skin folds.

Bioelectrical Impedance uses a portable instrument to conduct an electrical current through the body to measure fat.

Underwater Weighing is a method of determining the proportion of fat to lean tissue.

Circumference Measurements can be used to calculate body fat percentage. Measurements are taken from the neck, chest, waist, hips, thighs, calves, and biceps. This is a good method to utilize for a goal of altering body composition. 


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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.