What is the point of "descending?"

Good Morning I am reading about how to structure workouts and many recommend that I descend my times in a series of intervals. I know what it means but wonder what is the physiological basis for doing it. Regards Spudfin Not much Physiological basis for doing it, trying to justify descending sets in temrs pf physiology will result in lots of hand waving. Lots of mental and pacing reasons for doing it though. I like to do some descending sets just afetr warmup if I am going to do some hard swims and will be watching times. Sort of an after warmup, warmup.

Good Morning I am reading about how to structure workouts and many recommend that I descend my times in a series of intervals. I know what it means but wonder what is the physiological basis for doing it. Regards Spudfin Not much Physiological basis for doing it, trying to justify descending sets in temrs pf physiology will result in lots of hand waving. Lots of mental and pacing reasons for doing it though. I like to do some descending sets just afetr warmup if I am going to do some hard swims and will be watching times. Sort of an after warmup, warmup.