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Abs mostly Red muscle fiber?!?!?!

I was just reading a Q&A article written by Charlie Francis (Found on T-Mag site). He claims that abs are mostly Red muscle fiber (“RMF” sorry I’m lazy). So according to him (and many others) you should train RMF with high volume and a high frequency (almost daily!). White muscle fibers should be trained with heavy weights and low reps on an infrequent basis. (Damn there is alot of setting up before you ask your question). What I want to know is are abs (and calves for that matter) composed mostly of red muscle fibers? I’m having a hard time believing this because most of the full body training routines on most sites dont reflex this reality. :slight_smile:
Thanks guys

The rectus abdominus is primarily white fiber. If your primary goal is cosmetics then stay with a higher resistence as if you were training any other body part. The soleus is primarily RMF. Gastroc tends to have a bit more White fiber but I find higher reps with longer TUT is the best methodology for size. I feel that since the ROM is so small at the ankle joint one needs to do more reps to meet the TUT requirements for hypertrophy.

Sorry if I’m wrong, but I thought red muscle fiber is actually fast twitch muscle fibre, and white twitch is slow twitch?

ACtually it’s reversed. Just look at chicken – white meat at the breast (fast twitch) and dark meat at the legs (slow twitch).

Nope. Red is slow, white is fast. To remember this just think of a chicken. A chicken’s breast meat is white because it flaps its wings in short bursts, but it has dark meat on its legs because it spends a lot of time walking around.

Some of the recent studies I recall seem to indicate the abs are of mixed fiber composition in most people so you should hit them with a variety of rep ranges. The postural muscles of the abs tend to lie deeper and are more slow-twitch oriented whereas the phasic muscles are more superficial and tend to be fast twitch oriented. As for calves the soleus tends to be predominately slow twitch whereas the gastrocnemius is more fast twitch. So for movements where your knees are locked (gastrocs) you’d generally want to do fewer reps then when you perform exercises with your knees bent (soleus).

i wouldnt worry about it too much Roman. Its way more complicated and individualized than this, you must also take perspective into account too…

well, i guess the chicken example works, but to be a little more scientific about it:
red = oxidative = slow twitch
white = non oxidative = fast twitch
if a muscle fiber is red, it means it has more hemoglobin (i think, or it might be mitochondria), which means it contains more oxygen, which means it will be able to last longer during exercise.

Nic, more Myoglobin actually, but otherwise correct.

That is complete BS. The amount of white or red muscle fibers in a body part is completely based on genetics. You shouldn’t treat your abs any differently than your other muscles: Failure and recovery.