The following is an excerpt from the Jim Wendler Forum - it is in response to a question from a forum member that wanted to increase his deadlift. It wasn't a specific question; more it was any suggestions that any of us had regarding the deadlift and how to increase it. Additionally, he also had a question regarding being weak at the bottom of the movement.
Here was my response:
For assistance (not supplemental) just make sure the "big" things are taken care of: strong erectors (back raises for variety of reps; done "heavy" for sets of 10 using a bar on the back or limited ROM while holding DB's. Also do higher rep, controlled reps. In other words, don't just make it strong in ONE way.) Generally any kind of abdominal work will help. I don't know if it's still going on but their was a lot of internet propaganda about never needing ab/low back work for squats/deads; this is being peddled by idiots. Yes, if my mom wants to just squat and deadlift, she will be OK with not doing ab/low back work. However, when the average guy wants to push these lifts, you have to create a VERY strong midsection. Every single STRONG lifter I've seen, even in the lower weight classes has a VERY thick midsection. So don't fall in line with the current (or perhaps it has passed) party line. A strong midsection helps every part of the lift but is very important for the bottom position.
Also, lots of back raises and even GM's (back raises are GM's without the politics) really stress the hamstrings. And back raises limit the weight you can handle which means they can be done for higher volume AND not totally beat you up.
Second, generally speaking some kind of row will work, but I would recommend DB over everything (for grip and strength), and a barbell over any machine. This generally helps lockout due to being able to pull yourself "up" into position once the barbell is passed the knees.
As for supplemental lifts, be wary of what you read. If someone went waxes poetic about deficit pulls but his deadlift went from 315 to 400, big fucking deal. It looks great when you don't see the big picture. For example, "These put 85lbs on my deadlift!" Well at that level, it doesn't really matter that much. I'm not being a dick but at that level, it's more about the work and time NOT about the special movements.
Deficit pulls, again, is the party line but the one reason they don't always work is that your quads do most of the work; which is great except when you pull "normal", you don't have all the quad power. This doesn't mean they don't work, it just means it isn't a 1:1 carryover, or whatever. However, strong quads are VERY important and one reason why the leg press is a great compliment; you can do a lot of work with (generally) low strain on the body. Don't worry so much about doing a ton of weight, rather use this for as big of a ROM as you can and don't be afraid to do 10/20/30 reps on these. For two years, on every single Monday, I would do the EFS Power squat machine, 45 degree back raises (with barbell across back) and roman chair sit-ups with weight held behind my back. I slowly worked up, set after set, on the Power Squat, adding only two plates at a time; one on each side. I usually did sets of 10, working up well past 1100lbs most times. This was a ton of volume, didn't have to worry about "form" and my squat/deadlift improved greatly due to having strong legs. Literally, did these 3 movements every Monday for two years. So find a way to get some leg work into your training that you can just "do" and not worry about the angle of your forearms in relation to your hip joint and all that bullshit; just find something you can use in a "stupid" manner.
As for DL training, understand that (again) the internet is much separated from reality. Once you get to a certain level, you can't remain at your best all the time. There's an old saying that only the worst are at their best all the time. And also at this point, adding 5-10lbs might require every bit of effort and time as it did to add 50lbs. The stronger you get, the harder this shit gets. So if I were you, I'd break up your goal into very manageable goals and understand that an 80lbs jump is HUGE at this level. Also understand that if you go balls out on this, don't expect other shit to increase and some shit may go down. Live with it; accept it. The volume you need to do is very dependent on any number of things including your training level, your build AND what else you are doing for your other lifts. Generally speaking, a few heavy reps during a workout complimented with lighter sets (FSL work) seems to work for majority of people.
At the end of the day, any lift you want to do you have to just get stronger; so don't overthink this too much. It seems that the current infatuation with people is to treat all training like they are Olympic lifts. Ya know, "technique is EVERYTHING". And while it's nice to have good technique it's great to have strong lifts. At some point, you gotta add some weight and get strong.
(BTW: these are the same people who won't spend the time doing the work and wonder why they can't raise their lifts passed "normal" or their legs to the bar on a hanging leg raise.)
Also, make sure you are eating enough because again, you gotta fuel the tank for what you are trying to achieve. And what you are asking your body to do IS NOT NORMAL and what gets Frankie Forum to a 315 (hitched DL on Instagram) isn't what's going to get you to 660 on the platform.
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