Asked by: Mark Wells, Littlehampton
Physiologists used to think that the muscles controlled their own effort levels, shutting down when exhausted. We now know that the brain plays a much bigger part, and that fatigue signals from the muscles are weighed in the context of motivation, beliefs and expectations.
When we’re in a life-threatening and adrenaline-fuelled situation, it makes sense that the brain abandons its usual conservative approach and instructs the muscles to work much nearer their full capacity. But also bear in mind that many anecdotes about superhuman strength are not as incredible as they first seem. For example, it’s usually one corner of a car’s bulk that is briefly lifted, not its full weight.