Training with heavy partials is a very old training method which has fallen out of favour in recent years. Many big strong guys got incredible results from incorporating partials into their training. Two guys which come to mind are Paul Anderson and Bob Peoples. Anderson used partials almost exclusively for his squat training and ended up squatting a disputed 1200lbs. Whether or not he actually did this he was certainly a very strong squatter with lots of witnessed lifts in the 800-900lbs range. Bob peoples used partials for the deadlift which he was built perfectly for with massive monkey arms. He ended up pulling around 720lbs at 180lbs of bodyweight. Both these guys did these lifts before power racks were widely avaible and ended up digging a hole in the ground with the barbell placed over the top. They would lift in the hole and overtime start to fill it in until they were doing their lifts with a full range of motion.
There are a few reasons I feel partials are no longer as popular as they used to be.
They were widely used from around the 30s to the 60s with many strongmen from those eras advocating them. In this time those who lifted weights did so to get strong and to compete in weighting. After this bodybuilding started to take over and training for strength became less important. Partials are a pure stength training method and don't have a place in a bodybuilders routine, So partials and strength training in general fell out of favour while bodybuilding grew in popularity.
Many current strength athletes opt for accommodating resistance methods such as bands and chains which achieve a similar effect but aren't quite the same animal and don't quite cover all the benefits I believe partials have.
The final reason that partials aren't popular as its viewed by many lifters as ego lifting. But there is a difference to a beginner half squatting or only unlocking their arms on a bench press than a serious lifter using partials in addition to full range of motion lifting. The former is simply ignorance to what full range of motion is and how a exercise should be performed. While the latter is an assistance exercise to compliment full range of motion lifts. Its not to brag and say "look how much weight I lifted for 2 inchs!" No one cares how much you lift in a partial. Its simply an assistance exercise and should be treated as such.
All of this aside there are many advantages to including partials in your training.
Firstly partials build epic core strength. The body requires great stability to be able to support weights much heavier than your full range max even if it isn't moving them very far. The abs, obliques, lower back, upper back and internal core muscles are having to work super hard to maintain the neutral spine during the lift. These muscles can be worked much harder than during a conventional exercise as the prime movers are no longer the limiting factor. You will really have to brace hard and hold your air during a heavy partial and I would advise you to do them without a belt on. Unless you have a very weak core you should find that you can handle weights beltless greater than yor belted full range lift.
Tendon and ligament strength. Many old timers believed that great strength could be achieved by not only developing the muscles but also the tendons and ligaments as well. They used partials as a means to do this as it overloaded the tendons beyond what the muscles could handle during a full range lift. This in turn would make you stronger without increasing your bodyweight as well as making you more resistant to injury. To further develop the tendons perform a ultra high rep pumping exercise on top of this. Tendons have less blood supply than muscles and require much greater volumes to build them that 3 sets of 10 just can't achieve. Working anywhere from sets of 30 to 100 reps afterwards should give you tendons like a terminator.
Heavy partials can give a great psychological boost to your training. By getting used to handling heavier weights suddenly normal working weights done through a full range of motion don't feel as heavy. Having 200kg on your back is no longer a big deal once you are used to supporting 300kg. While there is obvious physical strength to be gained from training partials from a stronger core, tendons etc there is also great confidence to be gained in their training as well.
Heavy partial training when done from a deadstop can help strengthen your full range lifts by making you stronger through a sticking point. When doing a full range lift there comes a point where the bar is at the least mechanical advantage and will slow down. If the lifter is strong enough they will grind slowly through it to complete the lift. If they are not this is the point at which they will fail the lift. This is known as a sticking point. It can be on different parts of the lift and will differ between people. You might be weak off your chest in a bench, weak at the mid point in the squat and weak at lockout in the deadlift for example.
Take a average gym goer who does half squats. Not because he's doing partial training but simply because he's ignorant to proper full squat technique. He takes the bar out of the racks slightly unlocks his knees and comes up. This kind of partial creates a stretch reflex on the muscles at the bottom which helps you come up stronger. Now when coming up from a full squat and you hit your sticking point the stretch reflex as all but gone and its up to you to grind the weight out.
Partials perfored like this with an eccentric action first creating a stretch reflex will not carry over to full range lifts very effectively. How ever if you perform partials from a dead stop by using the pins on a power rack you have no stretch reflex. You will be relying on pure strength alone through that specific range of motion. You will find that partials done this way are hardest when trying to get them off the pins and that you really have to slowly grind through them. This will teach you to grind through the same sticking point in a full range of motion lift. It is this reason that I feel dead stop partials are superior to accommodating resistance training methods such as bands and chains when it comes to raw lifters.
So what partial exercises can you use and how should you implement them into your training?
While any exercise can be done with a partial range of motion there are only a few which are beneficial in the ways I have described.
Partial squats done off the pins in the power rack at varying heights.
Partial front squats off pins. Never tried these but I'd imagine they might be quite hard on the knees. These supposedly worked well for Dan John at improving his cleans.
Partial over head squat. Never tried this but probably a beast of a core exercise
Rack pulls from various heights or block pulls
Bench off pins at various heights. I believe these would work better than the fabled board press as the board press still creates a stretch reflex. It might be useful for geared guys but the Bench off pins will have more carryover to raw benching.
Overhead press off of pins. These are great for core strength. If you are short or your gym has a really high powerrack you can do these. I'm 5'10 and most racks are to low to lockout.
Incline press off pins. If you use inclines as your main press you might want to get stronger at them by doing partials
Seated press off the pins. Doesn't have the same core benefit as standing overhead press partials but still helps you get stronger over head
Partial weighted chins. You have to be able to set the bar at different height and pull from an already bent arm position so a Smith machine works well for these.
Partial one arm chin ups. I write about these in the one arm chin post.
Partial curls off pins. Yes this would mean curling in the squat rack so don't do them if someone is waiting to squat. I believe arm wrestlers use these as well as those who compete in strict curl events. It would also be a great way to strengthen your tendons to help prevent injuries from deadlifting or strongman.
When it comes to adding them to your training program I suggest doing them after the full range lift as an assistance exercise. You should only use singles to train dead stop partials otherwise you are creating a stretch relfex between reps and losing some of the benefits. You can do high sets anywhere from around 6-15. You could also do them rest pause with around 5-10 seconds rest between reps. Just make you are not supporting the weight in between pauses and that it is resting completely on the pins.
You can use various heights when training partials. I would suggest if you have never used them before to work from around the middle of the full range lift.
As you become accustomed to using partials you can use what the old timers did which was progressive movement training. This is starting at the top of the range of motion and very slowly overtime increasing the distance until you are doing full range lifts.
Make sure you build up slowly when doing partials. With such high loading on your body your joints will start to hate you if you go too heavy too soon or over do the volume. I would suggest you don't do partials more than once a week for each body part and you may even want to alternate each week between squat/Deadlift partials as they both put a lot of stress on the lower back. Don't go any heavier than your full range max your first few sessions then slowly increase the weight and sets from there. Doing partials from a dead stop off the pins in the power rack is a safest way to do them because if you are not strong enough the bar simply won't move but there is still a risk of injury. You are building your tendons and ligaments which take a ling time to develop so don't rush you have been warned.
To get the full tendon building effects it is good to perform high rep pumping exercises afterwards to get maximum blood through the tendons and ligaments. Aim for around 100 total reps split over several sets.
Some exercises which work well are:
bodyweight squats/kettlebell swing after partial squats.
45 degrees back extension/ banded good morning/ kettlebell swing after rack pulls.
Push ups or wall push ups after partial Bench or incline.
Dumbbell press or band press after overhead partials
Empty Olympic bar curls after partial chins, one arm chins or partial curls.
That's it! Regularly include partials in your training and after a few years you will become both an unstoppable force and an immovable object.