Are "muscle density" routines/training a scam? Isn't diet & cardio going to get you to a place where your muscle looks "hard and full, with paper-skin"? Or, is there actually some substance to the info out there?
Thank you for your time.
My Answer: Well I don't know what sort of training routines you're looking at, but different types of training can get your muscles more "dense." What do we mean by muscle density?
Muscle density refers to how thick and hard the muscles look and feel. This is different from "training density," where you do more work per unit of time. Muscle density is developed through sarcomere hypertrophy. In other words, the muscle fibers grow by thickening in diameter. This is different from sarcoplasmic hypertrophy where your muscles grow from increased fluid retention.
How do you develop sarcomere hypertrophy? Heavy weight and low reps. Anywhere from 3-8 reps, with a target rep range of 4-6 reps being ideal.
So cardio is not the way to go if you want muscular density. If anything, you will lose muscular density, because cardio is based on low weight (or more accurately, low force production) and ultra high reps, the exact opposite training method.
But if you want paper thin skin, then diet plays a crucial role. A cyclical ketogenic diet as mentioned in Training for the Busy Bodybuilder is the way to go.