The Olympics may be over, and the majority of the athletes have left London, but another crop of athletes is arriving for a new set of games. The Paralympics, less touted but no less inspiring than the sports of their able-bodied counterparts, pits athletes with various physical disabilities against one another in an array of sports. Even though less attention is put on these athletes, it does not mean that there is any less of a pressure to compete. Just as some able-bodied athletes attempt to hedge their bets at winning the gold by doping, so do Paralympics athletes attempt to have a boost - literally. As many as a third of Paralympic athletes with spinal injuries are deliberately hurting themselves in order to enhance their performances.

The practice is banned by the International Paralympics Committee (IPC), but it is difficult to catch. Called boosting, athletes break their own toes, sit on sharp objects, or strangulate their own testicles. One quadriplegic climber, Brad Zdanivasky described to BBC how he would give his toes or legs some electric shocks.

The activities are done to raise blood pressure and ultimately improve performance. In able-bodied athletes participating in difficult physical activities, blood pressure and heart rate increases automatically. But in athletes with spinal cord damage that increase does not occur. Boosting provides that.

But the practice does not come without danger. In medical terms, athletes are deliberately causing autonomic dysreflexia (AD). For many quadriplegics, uncomfortable activities like sun burning can set off the condition automatically.

The blood pressure spike could conceivably blow a blood vessel behind the eye, cause a stroke, or stop the heart.

But, even though the practice has been banned by the IPC since 1994, very few studies have sought to find out just how many athletes boost.

The IPC also does not take into account blood pressure levels or heart rates, or have any systematic method at watching for this practice. Instead, the IPC says that they will continue to monitor athletes, pulling aside anyone suspected of boosting. Symptoms include sweating, skin blotchiness, and goose bumps. Anyone found with blood pressure levels over 180 mm will be removed from the particular competition, but there is no mark on their records or a long-term ban. Those methods can be inconclusive though, unless there were regular tests of a long period of time, stating whether the athlete was boosted.

Officials worry that someone will have a stroke one day on the field, bringing the problem into the open.

Unfortunately, it is easy to see why athletes take the risk. The benefits are certainly tangible - there is a distinct difference between athletes with normal blood pressure and those with elevated levels.

The games start August 29 in London.