Is there actually such a thing as lean muscle mass (as opposed to fat muscle mass?)

[enwar3]

Ok, I've always been under the assumption that all muscle is basically the same. I thought uscle perceived to be "toned" were only so because of a lower body-fat. Underneath the fat, all muscle is equal.

Now is that actually right? Or is there such a thing as differing densities of muscle fibers in muscles, to the point where you can actually train to get "bigger" or "leaner, more dense" muscles?

(I did some internet surfing today and it got me all confused)

 

[KoolDrew]

Now is that actually right?

Yes.

Or is there such a thing as differing densities of muscle fibers in muscles, to the point where you can actually train to get "bigger" or "leaner, more dense" muscles?

No.

LBM = lean body mass, which is your body weight minus the fat weight. A lot of people confuse this term and say "lean muscle mass" when they really mean lean body mass.

 

[presidentender]

Dude, you have no idea. My muscle is soooo lean.

Seriously, though, there are different types of muscle, but it's fast/slow twitch, not lean/fat.

 

[skace]

Originally posted by: enwar3
I thought uscle perceived to be "toned" were only so because of a lower body-fat. Underneath the fat, all muscle is equal.

"Ripped" would be significant muscle with a very low body fat %.
"Toned" would be significant muscle with a slightly higher body fat %.

I can't find proof of this anymore, so I'm posing this next part as a question for anyone who does have valid proof since I'm going on memory. I believe you can change the shape of your muscles by training improperly. For instance, doing bicep curls without a full range of motion will create a smaller muscle (the muscle will be tall/wide, but not long).

I don't know what kind of effect slow and fast twitch fibers have on anything other than functionality. I don't know if anyone has done tests where 1 person attempted to specifically target slow twitch while another specifically targeted fast twitch.

 

[spamsk8r]

There are actually 2 different types of hypertrophy: sarcoplasmic and myofibrillar hypertrophy. Sarcoplasmic makes the muscles larger without an increase in strength (due mainly to the ability to store additional fluid), whereas myofibrillar hypertrophy does come with a strength increase. So there are subtle differences in muscle mass, but not with regards to fat/lean. Myofibrillar hypertrophy produces muscles that are not necessarily as large, but are stronger.