To be clear on this , I don’t think metabolic conditioning is a scientific term . Aerobic conditioning, sure! Anaerobic conditioning, also is a scientific term. Metabolic conditioning can be either aerobic or anaerobic, or both. Por ejemplo, Dr. Darden’s chin/dip/sprint routine is a mixture of aerobics and anaerobics. This combination will definitely decrease the effect of one or the other or both moieties. So I am not of the belief that metabolic conditioning works well.
Face it, long, slower, time consuming steady state cardiovascular conditioning works. Resistance training works well. These training moieties do something different for the human body. All the experts agree, except a few HiT aficionados. Can several anaerobic workouts a week succeed for average non-drug guys? I see little evidence for such a proposition to enjoy success. Your mileage may vary!
Marc