Every time you enter a lift you see a notice saying the maximum amount of people that should be in there. When engineers design lifts, bridges and buildings they have a safe working load (SWL). If I remember correctly from my O level Mechanics, the absolute maximum load is two and a half times the safe working load.By coincidence this figure of 40% of maximum is the same as the percentage of muscle fibres we recruit when we do a single maximum repetition lift, which should represent our absolute strength.The brain decides how many fibres to recruit to overcome the task and the brain can be fooled. How many times have you gone to pick up a container that you thought was full but was in fact empty and it shoots up in the air; conversely, when you go to pick something up, usually your wife's suitcase which you foolishly believe would weigh the same as yours as you are embarking on the same journey, you find that at first it remains stubbornly upon the ground. This is because the brain has either over- or underestimated the number of muscle fibres needed to carry out the lift. If the brain can be fooled into recruiting more fibres than it needs, can it be conditioned to go beyond this 40% figure to improve performance?One of the possible explanations for this maximum of 40% fibre recruitment is that the brain has to hold back fibres to enable their use in rotation for repetitive actions. Another possibility is that this 40% is part of the evolutionary process. This would in part explain how early man, standing under five feet tall, would be able to pick Sir Steve Redgrave up above his head and hurl him across the room (or cave). When compared to modern sporting giants, early man was far stronger in absolute terms, despite the fact that today we have better nutrition and scientific monitoring of training. Could it be that the explanation for this is that no such SWL existed in early man and he was able to summon all his potential strength? Apart from the safety aspect of a SWL, if we operate anything at below its maximum it lasts longer. Early man drove with the pedal to the metal and would be lucky to see his twenty-first birthday, let alone take part in competitions at age 90 like John Hodgson. Nowadays there is not the demand for man to hunt down dinosaurs and throw them roughly to the floor single-handed [Tel appears to be ignoring the fossil records and instead relying on The Flintstones for his knowledge of the lifestyle of early man]. Modern man driving his body with due care and attention gets his full 3 score years and ten.In support of this theory, when basic instincts come to the fore people are capable of phenomenal feats of strength. A case study from a course I attended told of a young mother who, whilst backing her car off the drive, inadvertently ran over her toddler. Without a second thought she ran to the back of the car and lifted it up, releasing the child. Had she thought about it she would never have been able to lift the car but her maternal instincts to protect her child were so strong they overrode all other considerations. Although we can fool the brain to recruit more fibres than we need, whether you could consciously summon up all of your potential strength and override the SWL I doubt. There is something we can achieve by applying positive thought. When we are children we learn to overcome the most difficult tasks we are ever likely to meet. We don't do this with the aid of a user manual but by a process of trial and failure. As children we have no awareness of difficulty and no fear of failure; these come later in life and create barriers.If we can approach tasks with the mind of a child, open minded and fearless, then we will be able to improve performance. If we don't, there's always next time.