This study showed that independently of the method for weight loss, the negative energy balance alone is responsible for weight reduction.
pubmed.ncbi.nlm.nih.gov
Conclusions: This study showed that independently of the method for weight loss, the negative energy balance alone is responsible for weight reduction.
Meaning that: It doesn't matter if you are training/exercise or not. If your diet isn't optimized and you are overconsuming food/energy you won't loose mass (fat).