The abdominals are predominantly phasic muscles ( fast twitch), just like the hamstrings, you don’t do high reps of 50 + reps to build hamstring strength do you? So why then with the core?
To build a bullet proof core, to withstand a potent body attack, you must use resistance to strengthen the rectus abdominas and external, internal obliques. As you can see in this pic here of a crunch with a dumbbell on the swiss ball. Notice the greater range of motion on the ball, compared to the crunch off the floor, notice how the spine is cradled and protected and how the abdominals can work in a greater range of motion.
Notice the hands behind the head on the crunch exercises, another mistake, this exercise creates an imbalance in the flexor chain ( neck, trunk, hip) which will then create the common forward head posture and kyphotic posture shown in the attached pic, just so those of you that don’t know what kyphotic means, you see it and you see this posture in a lot of experienced fighters, it IS the posture of the sport, and the cause of muscle imbalances.
Gravity wears on us everyday, with being sedentary, and bad ergonomics ( sitting hunched over, hunched over, flexed over looking at a screen or game box for hours at a time etc) postural muscles (tonic) become tight, phasic muscles become weak and your faulty posture is a reflexion of that.
so, again, why crunch or do the biggest bastard off an exercise you can do in the setup? Read the work of Dr. Stuart McGill, the worlds authority on back pathology & performance and you will be educated on far better choices in your exercises selection, ergonomic set up in life style, and core and low back performance.
There is always a cause and effect with out training, risk versus reward, accumulation of what we think we know in what we do, or fail ton understand in what we do.
I hope this helps you in doing so.
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