proven correct but logically makes little to no sense to avoid training a muscle at its strongest point which is maximum contraction, if you can do a weight at its lengthened position-then skipping the contracted position seems silly.
Those studies need to be looked at as i doubt they were done at a contracted rom with more load as they would have had to be because you can handle more load at a contracted position than at a legnthened position therefor if the load is adjusted for the strength curve would the studies say the same thing?
a solution would be zone training. but that is added volume.
Studies are more for cashing in on n00bs by influencers claiming “Science based” and mental masturbation. Everybody with actual experience in the gym are going to stick with things that are working that they like and ditch what they don’t. Most vets know that the takeaway from studies tend to paint with a broad brush and look at trends because looking at the individuals, they will all experience varying levels of growth which each different stimulus. Some are hyper responders, some don’t move the needle at all. This goes for volume studies, studies training at different Muscle lengths, frequency studies. Your mileage will vary from mine, so figure it out yourself. Studies don’t prove or disprove anything in the world of muscle building. They can SUGGEST things or point to POTENTIAL outcomes, but they can’t give concrete answers and any intellectually honest person will admit that.
As an anecdote, Jason Gallant and Phil Hernon liked to mostly focus tension of a rep in the mid range, keeping tension on the muscle in more of a mid range partial.
This can be accomplished easily with a bar squat using accommodating resistance. It is “fun” coming out of the hole and start feeling the weight getting harder the further you push.
America is full of people who do partial squats on a daily basis; several times a day and for long periods of time. They all look like crap and move like their 80 before they are 40.
It does seem like “lockout” leg presses are all the craze at the gym that I have trained the last 10 years. Far more do partial leg presses than make any effort to get deep enough to involve the hips.
the contracted position is the weakest position for the muscle, we only can move more load in that position because the leverages are so good. But the contract position is almost worthless for muscle stimulation (only a very small percentage of the crossbridges can overlap when the sarcomere is compressed).
This is kinda the idea behind accommodating resistance like bands, chains, or reverse bands. It’s a non- constant force curve, and ideally you tune the band resistance so that there’s no “easy” part of the lift.
Fibers are recruited based on neural output, not the length of the muscle. The actin-myosin crossbridges overlap the most when the sarcomere is close to a stretched position. Muscle length has zero to do with recruitment. Muscle force is based on total crossbridge attachments in parallel and near the stretch is where that number is the highest.
from link below
" The active tension in the length–tension curve is generated by the contractile element of the sarcomere, that is, the interaction between the myofibrils. The peak tension is produced when sarcomeres are at their resting length, as this provides the optimum alignment between the actin and myosin filaments. When the length of sarcomeres shortens, the actin filaments are pulled along the myosin filaments, which, in turn, pulls the z-lines closer to the myosin filaments. At extremely shortened lengths, titin is compressed between the myosin and the z-lines, and the actin filaments overlap each other centrally. A consequence of extreme shortening is that there is no further potential for myofibrils to contract, and little to no force can be generated"
Speaking entirely from the feel of a Strive plate loaded leg extension machine, when loaded where the effective resistance is higher in the stretched position and as I approached the full contraction the lighter resistance allowed a concentrated contraction at the fully flexed position. It was a very nice controlled feel.
I was clearly stronger in the stretched position than I was at the contracted position.
you are stronger at the stretched position than the contracted position because the stretched position was trained more than the contracted position as the case with conventional exercises which provide little to no stimulus at the contracted position unless adjusted for like those nautilus machines.
it may appear that way as you’ve been training with exercises and not strengthening the contracted position and only strengthening the lengthened position.
correct, as whatever weight you use to normally train the full squat, would be too light to tax the muscles at the fully contracted position at the top quarter.
I’m enjoying this trend where posters come on here with a question about their training ideas, then immediately shout down everyone and anyone who tries to answer it.
Note: Absolutely no accomplished squatter ever has their thighs in the fully contracted position. They come to a fully erect position, but never lockout their knees, and actually a fair number of degrees from lockout.
If you know anything about physics, you know that the mechanical advantage from standing erect with your knees very slightly bent (the normal top position of the squat) to the lockout position of the quads is very high. That is your knee straightens a few degrees and the bar path movement inside negligible. Of course you can’t do a normal squat with anything close to what you can lockout.
As with the leg press, I advise anyone I see lockout either of these two exercises that you will have a hyper extension event in your future if you persist locking out your knees.
Imagine that. The squat is very commonly known as the King of Exercises, and you never fully contract at the completion of the lift.