The deficit in weightlifting refers to when a weightlifter pulls a bar from a position that is lower than their traditional or "competition" variant. This method is used by many groups in barbell sports and strength & fitness in general and with that you can also count on seeing it done incorrectly as well.
BUT FIRST! Why the hell do we even do them?
Deficit work is generally prescribed when we see the following issues.
- Athlete cuts extension
- Athlete doesnt keep tension
- Athlete timing is off recieving the barbell
With that said, deficit work I strongly believe should be used only with experienced athletes that have been lifting for quite some time and also understand the details and can replicate correct form during traditional lifts over and over again. If your athlete is still making movement errors at "training loads" in their traditional lifts then deficit is NOT the answer and more coaching and practice IS the answer.
What we want to see when we DO take lifts from a deficit.
1. Setups will be lower obviously than traditional but athlete should be able to mimic start position best to their ability.
2. Hip to shoulder ratio remain the same, We should not see the hips shoot up before the shoulders rise (just like our traditional lift)
3. Timing component of lift should be similar to the pace a tradtional lift as if taken from floor but final extension and explosion will be later (time-wise, not position wise) than regular lift.
4. Extension should be full and upright in the proper position rather than rushing under. (defeats whole purpose of training)
Let's watch an example of a good clean taken from a 3 inch deficit
To break it down lets look at some variables.
First off we see the bar path, the same rules of lifting need to occur. Bar comes back off the floor sweeping into the lifter and then we keep the bar as close as we can while extending vertically. The line on the video gives a clear description of this cleans bar path.
When this is done incorrectly off deficit you commonly see a roll forward as the lifter is trying to find their start position rather then setting up tight from the beginning. To avoid this make sure the tension is set for the athlete to successfully start the lift nice and even with the bar immedietly coming back into them.
Secondly we see the athletes back staying flat from the setup and keeping a great ratio with her shoulders. This is extremely important as it shows the lift is leg driven and also they are not leaning back prematurely to use their spine to extend and generate force but rather their legs. This action also obviously keeps bar coming in close to the body and allows the proper pull to occur.
Lastly and most extremely important we see the athlete keep thier shoulders over the bar as long as they can leading to a very upright extension (the whole reason we are using the deficit). The deficit will teach athletes how to actually FEEL staying over the bar when they return to the traditional lift from the floor because they train the feeling longer during deficit work, IN THEORY when they return to the floor it will be natural to "hang out" over the bar and we will see great and long extensions with shoulders over the bar.
Like I said, I strongly encourage coaches and athletes wait until later in an athletes career to use these and keep this movement away from beginners. As a beginner there is already a million things to think about and do correctly so making it complicated more so will not benefit I assure you.