can you change body composition w/o gaining or losing weight?

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Yes, more so depends on your training age, if you’re a beginner and you get on a solid program and diet at maintenance calories in most cases you will lose fat and build muscle simultaneously, weight will typically stay within a 5 lbs fluctuations but you’ll notice changes in the mirror

I've been doing a strength program and I haven't lost a single pound but everybody's like dude you're losing so much weight

Thanks, I realized i was not very clear. But thank you for clarification.