Ok so i just measured my chest, arms, waist and its still the same as over a year ago. The shirts fit better but the weight hasn't decreased I understand about the body composition but if I'm changing shouldn't the measurements be less or more vs stay the same?
My first thought is that you are a little off on your measurements. A 1/2 inch difference would do it.
My second thought is this:
Cotton will stretch as the shirt is worn over time, especially if the cotton is loosely woven. It will stretch even more if the quality of the cotton is poor. And, of course, when a shirt says preshrunk, that may mean that the fibers were shrunk, but not necessarily the woven fabric or the completed shirt.
As a rule of thumb, weight loss is generally 75 percent diet and 25 percent exercise.
When I have lost weight, it was pretty obvious. When I do get stronger, I can lift heavier weights.
I have seen people lose a lot of weight just working out at home, using insanity / zumba type workouts and doing a lot of walking, watching their diet. Weightlifting alone isn't really focused on weight loss, but if you do HIIT type weight lifting, you get both muscle and cardio together.
ANd if you need DEXA scans, calibers, maybe electron microscopes? to determine if you have lost weight, maybe you haven't lost much weight?