Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
The rectus abdominis (RA)—the muscle made famous in movies and television—provides both core stability and trunk mobility (figure 2.9). The RA is a trunk flexor. This muscle arises from the xiphoid process and adjacent costal cartilages, and it attaches distally into the pubic bone at the crest and symphysis. The RA muscle is trained when an individual performs an exercise such as the crunch. Transversus Abdominis
The transversus abdominis (TA) is the deepest of the three flat abdominal muscles. The TA originates from the lower six costal cartilages, the thoracolumbar fascia, and the iliac crest; this muscle attaches medially at the linea alba (figure 2.9). The TA is reported to play a significant role in core stabilization, especially during rehabilitation (Richardson et al. 1999). Obliques
The external and internal oblique muscles rotate and side bend the trunk. These muscles also contribute to spinal stability.
The external oblique is the most superficial muscle of the three flat abdominal muscles (the external oblique, internal oblique, and transversus abdominis). The external oblique arises from the front lateral portion of the lower seven ribs, and it inserts into the linea alba, the pubic tubercle, and the anterior portion of the iliac crest (figure 2.9). Acting alone, the external oblique can flex the trunk, side bend the torso toward the same side (i.e., the side of the contracting muscle), and rotate the trunk toward the opposite side.
The internal oblique originates from the thoracolumbar fascia, the inguinal ligament, and the anterior iliac crest. The internal oblique also functions to provide spine stability, and it flexes and rotates the trunk toward the same side (table 2.4).
Also, please, note, that NONE of the abdominal muscles attaches to lower limbs. Hence, "lifting legs" does not directly influence them. You have to curl your pelvis, to actually engage abs.
I vouch for any machines that will stabilize your spine, keep lower limbs flexed AND engage your abs. reason being, should you check with say Kendall, Muscles Testing and Function, pay attention to iliopsoas complex. It's a bipartate muscle, consisting of iliacus and psoas major, that is attached to lumbar spine and proximal femur. When folks do situps on a bench, or anywhere else, with starting position "back flat" or "back extended", iliopsoas fires first, to pull trunk up into some flexion. This needs to be done to pull abs out of disadvantage, or full stretched position, so that they can engage and assist with trunk/spine flexion. Now, THAT results in major increase of lumbar spine curve, due to iliopsoas pull on points of attachment. THAT results, eventually, in damage done to lumbar spine AND impingement on nerves, exiting spine in that area.
Hence, proper ab crunch execution is with trunk slightly flexed in lumbar area, chin touching sternum at sternal notch, and entire spine slightly "pre-curled" into flextion. In this position, with femorae flexed, you shorten iliopsoas, and engage abs, to execute crunch.
This is why SITTING position in a ab machine is so advantageous. It automatically prepositions your trunk into safe position.
Oh, and as a resume: I am CPO, certified Prosthetist Orthotist with 20 yrs of experience in the field and exercising record of 32 years. And very bad back family history.
Guess, I'll toss my UW functional anatomy course and all the books out the window then, just learned abs do not flex the trunk...
What you mean by this?
Quote:
Originally Posted by ukrkoz
Hence, proper ab crunch execution is with trunk slightly flexed in lumbar area, chin touching sternum at sternal notch, and entire spine slightly "pre-curled" into flextion. In this position, with femorae flexed, you shorten iliopsoas, and engage abs, to execute crunch.
This is why SITTING position in a ab machine is so advantageous. It automatically prepositions your trunk into safe position.
Hardly anyone was talking about ab crunches, most everyone was saying they are a waste of time, and they are. It is no coincidence that people with the strongest abs do not do hardly any ab work, and would never even dream of touching an ab machine.
And from your post "...provides both core stability..." which is why people state exercises involving the core are the best ab workouts, seldom more is ever needed, and why those with good, even mediocre compound lift numbers have strong abs.
The rectus abdominis (RA)—the muscle made famous in movies and television—provides both core stability and trunk mobility (figure 2.9). The RA is a trunk flexor. This muscle arises from the xiphoid process and adjacent costal cartilages, and it attaches distally into the pubic bone at the crest and symphysis. The RA muscle is trained when an individual performs an exercise such as the crunch. Transversus Abdominis
The transversus abdominis (TA) is the deepest of the three flat abdominal muscles. The TA originates from the lower six costal cartilages, the thoracolumbar fascia, and the iliac crest; this muscle attaches medially at the linea alba (figure 2.9). The TA is reported to play a significant role in core stabilization, especially during rehabilitation (Richardson et al. 1999). Obliques
The external and internal oblique muscles rotate and side bend the trunk. These muscles also contribute to spinal stability.
The external oblique is the most superficial muscle of the three flat abdominal muscles (the external oblique, internal oblique, and transversus abdominis). The external oblique arises from the front lateral portion of the lower seven ribs, and it inserts into the linea alba, the pubic tubercle, and the anterior portion of the iliac crest (figure 2.9). Acting alone, the external oblique can flex the trunk, side bend the torso toward the same side (i.e., the side of the contracting muscle), and rotate the trunk toward the opposite side.
The internal oblique originates from the thoracolumbar fascia, the inguinal ligament, and the anterior iliac crest. The internal oblique also functions to provide spine stability, and it flexes and rotates the trunk toward the same side (table 2.4).
Also, please, note, that NONE of the abdominal muscles attaches to lower limbs. Hence, "lifting legs" does not directly influence them. You have to curl your pelvis, to actually engage abs.
I vouch for any machines that will stabilize your spine, keep lower limbs flexed AND engage your abs. reason being, should you check with say Kendall, Muscles Testing and Function, pay attention to iliopsoas complex. It's a bipartate muscle, consisting of iliacus and psoas major, that is attached to lumbar spine and proximal femur. When folks do situps on a bench, or anywhere else, with starting position "back flat" or "back extended", iliopsoas fires first, to pull trunk up into some flexion. This needs to be done to pull abs out of disadvantage, or full stretched position, so that they can engage and assist with trunk/spine flexion. Now, THAT results in major increase of lumbar spine curve, due to iliopsoas pull on points of attachment. THAT results, eventually, in damage done to lumbar spine AND impingement on nerves, exiting spine in that area.
Hence, proper ab crunch execution is with trunk slightly flexed in lumbar area, chin touching sternum at sternal notch, and entire spine slightly "pre-curled" into flextion. In this position, with femorae flexed, you shorten iliopsoas, and engage abs, to execute crunch.
This is why SITTING position in a ab machine is so advantageous. It automatically prepositions your trunk into safe position.
Oh, and as a resume: I am CPO, certified Prosthetist Orthotist with 20 yrs of experience in the field and exercising record of 32 years. And very bad back family history.
Great resume. Unfortunately, Stuart McGill, the world's preeminent spine expert, disagrees with flexing the spine for abdominal exercises. The spine only has so many loaded flexion cycles built into it and once it's up, it's up. It's like bending a credit card; you can bend it back into its original position, but it'll have that white line down the middle. Keep bending it and it'll snap in two.
Anyways, loaded flexion like rounded back deadlifts and sit-ups are exercises that uneccessarily put the spine in a bad position. Maybe a seated ab machine is better, but two things with that. First, who cares? There are better exercises for the abs and back. Second, McGill literally puts spines in a miniature ab machine and flexes them there until they give out. The core produces stiffness, movement comes from the mobile joints surrounding it. Hence, as was pointed above, powerlifters have strong cores; they stiffen and brace under extremely heavy loads
I'll stick with planks, bird dogs, loaded carries and the like
Do kettleball swings help your abs, if you do not walk? I've been doing these for years and I thought it was just for your frontal shoulders.
If you do a waiter's walk, how long do you hold the weight up?
Done correctly, KB swings will strengthen your hamstrings, butt, low back and abs; you shouldn't be using your arms/shoulders at all. This is a pretty common mistake, however and even trainers make this mistake. I did them improperly for two years before I felt my butt by accident one day.
Waiter's walks are generally done for time, anywhere from 30-60 seconds. Same thing with any sort of carry variation
Kettlebell swings are great for your abs. You need to hike the bell like a football and let it float up to shoulder height (kind of an upright plank). Think hike, plank, hike, plank, hike, plank. Look at videos from Pavel or Tracy Reifkind for good examples and steer clear of the videos from Jillian Michaels.
For farmers walks and suitcase carries I bought a couple of 7 gallon water jugs from Wal-Mart. Filled up each one is around 50 lbs. Just do laps around my backyard with them.
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.
Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
