Something to consider: What have you done to make your exercise more intense as you lost weight?
As would be expected, folks shouldn't start exercising intensely when they're very overweight. For me, I was out of shape, not used to exercise, and didn't have much strength or endurance. However, as I lost weight, I worked to also get more fit. I raised the intensity of my exercise as time went on -- not the duration (because that could readily lead to catabolization of LBM) but the intensity. I did more advanced yoga -- that required more endurance but also more strength. I hiked higher and more rugged hills. I decreased my home-to-work cycling time. Throughout a 100 pound weight-loss, I never experienced a significant plateau (as compared to when I lost weight thirteen years ago, when I experienced many plateaus along the way to losing 75 pounds).
Has anyone else found that increasing exercise intensity staves off plateaus?