How Are Humans Able To Lift Cars?

by Oliver Moras

A Chevy Camaro (Wiki Commons)

Many reports have surfaced regarding humans performing superhuman feats in life or death situations. The most common cases of these phenomena tend to be lifting cars to save lives. For example, in 2005, a man by the name Tom Boyle lifted a Chevy Camaro in order to free a trapped cyclist in Tucson, Arizona.

How much strength is being expressed?

Before exploring the science behind this wonder, it is important to gauge how much weight was being lifted. The average weight of a typical, non-truck, passenger vehicle would be around 3000 lbs (3 times the world record for deadlifting). Before assuming that regular humans could lift 3 times the deadlift world record (of 1155 lbs by Zydrunas Savickas), it is important to understand that in most cases of hysterical strength, the person is normally described to only lift a portion of the vehicle only slightly off the ground. In addition, vehicles aren’t evenly weighted and certain areas are much heavier (such as where the engine is located). The weight of the vehicle is also distributed by the wheels remaining only the ground (usually 3 or 4 of them), reducing the weight being lifted and the scale of the strength being exhibited.

Role of muscles

Regardless, an unusual amount of strength is still required to lift a car and this hidden strength can be partly attributed to muscles. The human body carries out functions in motor units, meaning in order to be efficient, we tend to use the minimum amount of muscles and nerves to complete a movement. It is estimated that even at maximal exercise, only around 60% of muscle mass is used; furthermore, even in elite athletes who have trained to increase their output, only 80% of their theoretical ability can be harnessed. The reason for our bodies holding back is safety. By using our full ability all the time, we would tear muscle tissue, tendons and ligaments and break bones so in order to prevent this, we limit ourselves.

Role of pain and fatigue

The mechanism in place in order to stop humans from exerting too much of their strength is pain and fatigue. During periods of high exertion, we feel pain which disincentives us from pushing further when we could - rather than our bodies, our brains are what prevents most humans from performing a feat such as lifting a car. In fact, studies show that triathletes are reported to have a higher pain threshold than the average person, which may allow them to push their bodies further.

Role of adrenaline

What allows people like Tom to achieve hysterical strength is the motivation provided by their dire circumstances which would allow them to ignore many more of the pain signals which their body would overwhelm them with. Another key factor would be adrenaline. The epinephrine hormone (adrenaline) boosts breathing and heart rate as well as giving muscles extra oxygenated blood for more contractions which in turn would allow nerves to gather more motor units to perform a movement (more motor units results in a greater potential force). Moreover, adrenaline could reduce pain sensitivity during a situation and all these factors would put the body in a fight or flight state. Similarly, drugs such as cocaine are able to decrease pain sensitivity and it is thought that this could be why users have been reported to be able to show exaggerated strength during encounters with police.

However, is it not only difficult but also unethical to create situations of peril in order to conduct research into this area and so very little, proven knowledge is known regarding how to express hysterical strength. Most information is only theoretical and this is an explored area.

Source:

https://www.bbc.com/future/article/20151020-did-one-woman-really-give-birth-to-69-children