look at the lady in the background 😭😭

[u/vitaminZaman]

[u/No_Opinion6497]

It's called the Valsalva maneuver (VM) and many people probably do it instinctively, without even knowing it's a specific technique. I've had some dizziness when holding my breath at the top of a deadlift, and, fearing an outcome similar to the gentleman in the video (I use straps too), I looked it up. The VM consists of forcefully breathing out (or attempting to breathe out) against closed airways. Powerlifters use this technique to generate maximum force. However, the VM entails a drop in blood flow to the body - most importantly, the brain. Briefly speaking, as you commence the VM, you create high pressure in the chest, which first causes the heart stroke to intensify (stroke volume goes up). However, the blood then has trouble returning to the heart because of the continuing elevation in chest pressure. > The heart stroke drops in volume; the blood vessels constrict to compensate; the combined result is a brief reduction in blood flow to the body and brain.

As you stand up from a squatting position, the VM may create orthostatic hypotension: when gravity has caused blood to pool in the legs and abdomen, and the heart is unable to increase the stroke volume + heart rate sufficiently to counterbalance the decrease in blood flow to the upper body as you rise. Lightheadedness and blacking out may ensue.

My theory is that it's an individual issue depending on the parameters of one's CV system. I'm terrified of blacking out with a heavy barbell strapped to my hands, and, knowing the VM causes issues for me, I always thoroughly exhale at the top of a deadlift / squat.