So-called high-intensity training is not usually (and certainly not exclusively) the best way to train. Let me say that brief training does have value, though training to limit reps or failure, less so. This kind of workout can deliver results-though for many it does not.

The amount of effort as measured against the results is often unfavorable. This is its key flaw, and is a conclusion from empirical evidence, not theories. It often works best as an occasional, not main, training method. If you like it and it works, keep doing it; but if it doesn’t, modify it or change to something else that does.