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Why Do People Get Light Headed From Deadlifts

Why Do People Get Light Headed From Deadlifts? 6 Key Reasons

The deadlift is one of the best exercises for strength and muscle growth on the planet. It’s a full body exercise that challenges you both physically and mentally. There’s no way to cheat a deadlift, you can either lift the weight from the floor or you can’t. 

The simplicity and absoluteness of this lift is what makes it so great. It’s also why many people look to push their numbers with this lift and load the bar with 45lb plates. 

For many though, an intensive set of deadlifts will often come with some unexpected side effects. A common one you might have experienced is becoming light headed or maybe even passing out from deadlifts. 

Therefore, we’ve compiled this piece to let you know: Why do people get light headed from deadlifts and how can you avoid it? 

Fainting 101

If you have ever fainted before, you’ll be familiar with the insidious sensation of losing consciousness. Perhaps you’ve come close to passing out in the gym; ‘seeing stars’ or felt lightheaded. 

These scenarios are caused when the brain doesn’t receive an adequate supply of oxygenated blood. 

Where the body is unable to accurately regulate blood pressure or the heart is temporarily unable to pump blood to the brain, the result is usually low blood pressure or fainting (referred to as Syncope in the medical world).

The Anatomy of a Deadlift

The deadlift is a powerlifting movement that activates almost every muscle in your body. 

Due to the mechanics of the deadlift, it is possible to move proportionately larger weights in comparison to other lifts. Due to the major pressure the lift places on the body, the potential for fainting is high. 

The heaviest deadlift on record is 501kg (1,104 pounds) conducted by Hafthor Bjornsson at 200kg bodyweight – a lift of over 2.5 times his own bodyweight. 

Since this lift is a compound movement, it places a large load on a chain of muscles including the hamstrings, glutes, back extensors, abdominal muscles, and trapezius. 

In order for your muscles to contract, they need a steady supply of oxygen. 

In the context of deadlifting, if you are training progressively, you are going to encounter a point where the increasing weight takes more physical effort and some sort of breathing strategy is needed to maintain the supply of oxygen to your muscles and remove the build-up of carbon dioxide from your lungs. 

Why Do People Get Light Headed From Deadlifts?

The main reason why people get light headed or pass out from deadlifts is because the lifter hyperventilates after inhaling or exhaling too quickly in rapid succession. It can also be caused by holding your breath during a rep which causes blood pressure to drop rapidly following the rep. 

Whilst it is possible that lightheadedness or fainting after a deadlift could be an indicator of underlying health issues, in most cases of healthy lifters, this adverse reaction can be explained by the following six factors. 

Note* If you are someone who has experienced fainting at the gym, this should be treated as an emergency, and advice sought from a doctor until the root cause has been identified. 

1. Poor Breathing Technique

One of the key reasons why people faint in the deadlift is down to poor breathing techniques. 

The deadlift places an immense load through the posterior chain (the muscles to the rear of your body). In order to stabilize the posterior chain, we need to ‘brace’ or ‘engage the core’. One way to do this in the deadlift is by taking a deep breath so that your stomach expands out. 

Hold your breath and set your core so that your spine is stabilized. This is called the Valsalva Maneuver and is a technique used amongst powerlifters. 

Holding the breath does two things, it builds up intra-abdominal pressure (stabilizing the core) and it increases pressure in the space around the lungs. 

The impact of this is an increase in pressure within the chest space which reduces the ability of the aorta to pump blood around the body (and in particular to the brain!). 

In theory, a successful Valsalva Maneuver should include holding your breath during the first upwards phase of the lift and then exhaling as you move past the sticking point of the deadlift. 

But how does this lead to fainting? 

Well… there are a few potential problem areas when using this technique. 

The increase in intra-abdominal pressure in the chest increases the stroke volume in the heart. This leads to an initial rise in blood pressure.

However, once the lift finishes, blood pressure decreases much faster than normal and it is this sudden drop in blood pressure that can lead to lightheadedness or fainting. 

Where lifters hold their breath in for too long (particularly where the lift takes too long to complete) this can also lead to a sudden drop in blood pressure and passing out mid-lift. 

Finally, for lifters who go ‘all out’ and celebrate the lift by shouting, this rapid release of breath can also lead to fainting. 

2. Holding Your Breath Too Long

Over the course of several reps, there is the potential to hold breath for too long, then begin a new rep straight away. 

Failure to exhale can mean that blood oxygen levels do not replenish between reps and this can reduce oxygen flow to the brain. 

Slow controlled exhales through the upward phase of the lift, pushing through the sticking point can ensure that breathing is maintained. 

3. Spending Too Much Time in the Setup Position

Cast your mind back to the school playground where your friends used to try and force their bodies to faint. They would crouch down and let all the blood rush into their head before jumping up at light speed. 

The blood returning to the lower part of your body can cause a drop in blood pressure. 

Unfortunately, spending too much time in the setup position (e.g using wrist grips) can produce a similar effect. The rapid transition from low head to standing, combined with the added exertion can lead to potential fainting.

4. Inadequate Warm-up

We all know that warm-ups are essential to performance, however during powerlifting sessions, it is not uncommon for lifters to wait long periods of time between lifts. 

This can be problematic because longer wait times between lifts can lead to accidental cooling down. Where lifters are sat down for too long and jump straight into a lift, blood that has pooled in the feet and legs is not fully distributed within the body. 

This can lead to fainting since the heart has to rapidly increase its stroke rate to pump blood to the muscles, before a potential drop in blood pressure. 

Additionally, progressing to heavy weights too quickly – e.g using large denominations of weights, means that the body hasn’t warmed up enough. This can place larger demands on the central nervous system and greater demands on the heart and muscles. 

In trying to progress too quickly, there may be a mismatch in energy requirements for each set. 

A progressive tool for lifters is to use fractionals – this is why fractional weights were invented.

5. Low Blood Sugar Levels

There is a high chance that at the point of attempting a heavy deadlift, your body might not be adequately fuelled. 

If you are in a large calorie deficit, are fasting, or not eating carbohydrates, there is a big chance that you may be in a hypoglycemic state. Should you enter into a state of physical exertion, your brain may fundamentally malfunction.

The early warning signs of low blood sugar levels include (but are not limited to):

  • Shaking legs
  • Pale and clammy skin
  • Blurred vision
  • Social irritability

It is important that you take action should you experience any or a combination of the above symptoms. 

You should consume some fast-acting carbohydrates (think an energy drink or banana) to allow your blood sugar levels to rise before assessing whether to continue or not. 

If this is something that you regularly encounter, it may be worth experimenting with training at different times of the day. In some cases, training before breakfast or dinner can lead to a hypoglycemic state.

6. Dehydration

Where training is particularly demanding, there is a possibility that you might not be adequately hydrated. 

Where this is pushed to the extreme, very low levels of hydration can be a direct cause of a drop in blood pressure. 

If you attempt to push heavier lifts in a state of dehydration (where your blood pressure is already low) you are going to increase the likelihood of dizziness or fainting during or after the course of the lift. 

Make sure that you are well hydrated prior to any physical exercise and familiarise yourself with the warning signs of dehydration; feelings of thirst (obviously), darker-colored urine, dry mouth, lips, or eyes, as well as potential dizziness.


Fainting during a one rep max tends to be associated with the Valsalva Maneuver. Where lifters engage in a long battle to make the rep, this can lead to a sharp drop in blood pressure that is too great for the body to handle and reduces oxygen to the brain. 

The likelihood of fainting taking place during or after the deadlift is more likely a combination of the above factors coming together in a perfect storm. 

Where possible, ensure that you are adequately prepared for any intense powerlifting sessions by paying attention to your nutrition, warm-up, and technique within the lift. Where possible, conduct your ‘higher stake’ lifting sessions with a peer….. just in case.

If you are new to the deadlift you may want to consult a personal trainer or experienced powerlifting coach to discuss or learn how to deadlift correctly as well as potential breathing strategies including the Vlsalva maneauver.

Finally, any fainting should be followed up with a visit to the doctor so they can make sure there are no underlying health issues.

Medical Disclaimer – The above is for informational purposes only  as we are not experts in the medical field. If you experience any issue with light headedness or fainting during a deadlift you should consult advice from a registered medical professional. 

See next – Are dumbbell deadlifts a good alternative?