WHAT MAKES MUSCLE, KEEPS MUSCLE From a specificity standpoint, if the goal is fat loss the general consensus is to train a metric ton and make yourself hate life and exercise till you can't feel the left side of your face. It's a faulty approach with regards to fat loss. Fat loss plans should alternatively be referred to as "muscle maintenance" plans. The idea should be to maintain or keep as much muscle as possible while in a caloric deficit. The easiest way to do so is to lift heavy things remind the body to hold on to precious lean tissue.
Traditional strength training should still be prioritized even if fat loss is the main goal. This isn't to say you can't help expedite the process with some strategically placed circuits/HIIT/or metabolic finishers. But if you've already ensured a caloric deficit via nutrition, adding tons of training volume via high(er) rep sets and endless metabolic conditioning is usually nothing more than a one-way ticket to sacrificing muscle. Don't forget to lift appreciable weight when dieting. Force the body to keep your hard-earned muscle.