ANSWER: Good question! Anyone who lifts weights is bound to run into some sticking points in certain exercises. About 99 percent of weightlifters take the easy way out and cheat on their form. But there is a better way.
The usual way individuals respond to a sticking point is by sacrificing good form. They either use momentum and swing the weight through the range of motion, or they contort their body in a way that the weight can be jerked through the sticking point.
Both methods can lead to injury and neither of them make you stronger. Swinging, jerking and contorting simply do not lead to functional strength - they lead to more swinging, jerking, contorting and injury.
The real solution to training through a sticking point is simple. Reduce the resistance and move through the limited range of motion at the point where the sticking occurs.
For real strength gains to be made, the weaker part of the muscle (think of it as the weakest link in a chain) must be the target of controlled partial rep work. No one likes to reduce the amount of weight they're lifting. But in this case, as in many other plateau-busting exercises, it works. As soon as the weaker part of the muscle gets stronger, you can return to full range of motion training without having to cheat.
A: "Hitting the wall" is that point in time during a long-duration event when the athlete drastically reduces his or her pace or intensity, or even quits the activity.
The main physiological reason for "hitting the wall" is glycogen (carbohydrate) depletion. Other factors also may be involved, such as dehydration or elevated body temperature, but running out of sugar in the working muscles is the No. 1 cause of the "wall" experience.
Early in the event, muscle cells utilize both carbohydrates and fat for energy. When the carbs are depleted, the muscles turn to fat for their energy source. Fat is not as readily available as sugar is and the muscles' ability to produce power and force is greatly diminished. That's the wall.
It's at this point that "mental energy" and pure determination take over. It's this determination that enables the athlete to complete his or her event.