I am a little confused on how to think about changing reps into time held in the plank
As per...
it is not meant to be held for long durations. long duration is not a goal with it
Isometric Action
The Plank is an Isometric Action; A "muscular action in which tension is developed without contraction of the muscle.''
An Isometric Action is the only type of Maximum Strength Training that allows an individual produce Maximal Force.
Maximal Force Production take place with
an all out effort of 10 second, usually much less time.
With an Isometric Action performed any long, Force Production drop like a rock.
A good article by Dr, John Rusin goes into this...
Let's bust three ab training myths, test for real abdominal strength, and learn the best way to build a strong, athletic core.
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Myth #2 – Hold Your Planks, Like, Forever!
In 2014, Mao Weidong set the world record for the longest plank hold according to the Guinness Book of World Records. Four hours and 26 minutes!
"
That's the stupidest thing I've ever seen."
While this feat was described as an impressive showing of "core strength, "
was it really?
I'm going to go out on a limb and say that
Mao's abdominal wall was not maximally contracted the entire duration of the hold. However,
he was able to hold on just long enough to position himself in a perfect orientation to hang out on the anterior pelvic ligaments and tendons of the hip.
World class strength? Not so much. Precursor to tendinopathies and ligamentous trauma? Yeah, that's more like it.
Wasted Time and Limited Results
Individual who persist with mega endurance plank training movements are wasting time that should be spent on shorter, more intense plank training abdominal sessions.
- you can start to do "clusters" of your planks. That is, instead of holding it once each time you go to practice, you will do it 2-3 times with a short rest in-between,
Cluster Set Planks
This is one of the most effective method for Plank Training.
Pulsing Planks
Essentially, this is Cluster Set Training: ,,,"Interrepetition rest... a rest interval after every repetition or after a certain number of repetitions."
This allows some Muscle ATP Restoration, which ensure greater Force Production for he next Isometric Action; which increases strength.
This is the only video demonstrates it,
What I would add to it is with each Pulsing Plank performed, a Maximal Isometric needs to be perform for 3-5 seconds.
Contract-=Relax-Contract Pulse Training Part 1
THE SCIENCE OF CORE TRAINING: CORE STIFFNESS & PERFORMANCE OVERVIEW (PART 1 OF CORE TRAINING SERIES) https://gcperformancetraining.com/gc-blog/corestiffnessperformance1 ...the function of the core is to transmit force, prevent force/power leaks and maintain the position of certain joints and...
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As per Dr. Stu McGill's research, note in the post listed above...
",,,Whenever performing a powerful movement, the muscles will go through 3 phases: contract/stiffen, relax, and contract/stiffen once again upon impact, showing a "double" peak in activation...''
The same application applies in a Pulsing Plank; greater Maximal Strength Force Production happens.
Extended Plank Timed Sets
Time Planks for let's say a set of minute or longer to some degree work the abdominals.
However, a very limited training value is elicited with that method,
Add that is Rusin's observation that in a Plank Brace for time, the abdominal muscle may not engaged that much.
As per...
15 seconds is the generally used length for hardstyle plank. If you can hold it longer, you're not contracting intensely enough...