I’m not surprised by their lack of muscle; unless you’re strength training a few times a week, you’re not gonna get muscle definition and without a lot of protein in ones diet, it won’t last. Just walking around with massive weight on your frame isnt gonna cut it and isn’t the same as doing targeted, muscle building moves with added weight. I had knee surgery in March and I’m now in the stage of physical therapy where I have to strengthen the muscles on my left side to match my right. It can be hard for me to do certain movements, but I keep at it and I impress my physical therapist every time I visit her!