The Valsalva Maneuver and Shearing Forces
Yesterday one of my softball girls was deadlifting. She came up to me mid-session and told me that everything felt fine on the way up, but things were feeling real wonky on the way down.
I walked over to take a look at her form and see what was going on. To the untrained eye, her deadlift was on point. She was pulling sumo-style, with her knees set up right above her ankles. She was taking a deep breathe, bracing, and keeping the bar close to her body on the way up and on the way down. She wasn't squatting the weight and was actually performing a fantastic hip hinge and using her posterior chain to lift the weight. If everything was right, why did it feel so wrong?
This girl was pretty strong. She's been training with us for quite a while and was no stranger to deadlifts, but she was just coming back from her season and hadn't been as consistent with her strength work. With that comes some rustiness. I noticed she was exhaling pretty forcefully at the top of her lift. Essentially, she was losing the brace she was working so hard to attain at the beginning of the lift.
I told her everything looked great, but that she needed to pay attention to her breathing and wait until the weight was safely on the ground before she exhaled. She took the advice to heart, and badda-bing-badda-bang, everything felt good again. The Valsalva Maneuver at it's finest.
The Valsalva Maneuver
The Valsalva Maneuver is a technique that should be employed for most of the compound, multi-joint movements, especially heavy squats and deadlifts. This technique entails filling your lungs with air, which creates a large amount of intra-abdominal pressure, and holding it while performing the lift. It's an incredibly important concept to master and we include bracing drills early on in our clients programs to help teach this. Performed properly, it should also feel like you're constipated and you're trying to push it all out the bottom end. It's always entertaining teaching the valsalva maneuver to a new client after I've had lunch, as it usually includes an unexpected fart or two...
During squats and deadlifts, the force of the weight and gravity is constantly trying to rip you apart. The goal of strength training is to resist these forces and make you a more resilient human being. There are a total of 76 joints in your spine and pelvis, the skeletal core of your body that craves stability if you are to perform optimally, which experience a mix of compressive and shearing forces while under load. These shearing forces were the king of the show in yesterday's deadlift session.
As you can see from the depiction above, shearing forces are forces that act on a joint parallel to the joint surface and attempt to cause the joint to slide out of position. The valsalva maneuver counteracts these shearing forces by exerting pressure on the joints to resist displacement. Our athlete in the above scenario was achieving a nice, tight brace at the beginning of the lift, but was expelling all her air at the top, losing this spinal stability and allowing the shearing forces to take over on the way down. By cuing her to hold her brace, she was able to maintain this intra-abdominal pressure, thus maintaining spinal stability throughout the movement.
Keep this in mind the next time you experience back funkiness while performing your deadlifts. Are you bracing? Are you maintaining that brace throughout the entire movement? As usual, the devil is in the details.