My husband and I were talking about how Maggie is growing. Her BMI is great right now. In fact, according to the charts, she should have a little chub...But she doesn't have much fat on her. We were thinking she's more muscular than chubby, yes weird for a 5 year old. Anyway, my husband thought that all the time she does on the VEST is building up and strengthening her core muscles, thus gaining more muscle than fat. Just sharing our thoughts on other benefits of the VEST.