The deadlift is one of the three power lifts. It is also a great exercise for building total-body strength and power. It is an excellent predictor of performance in high-power movements such as jumping, sprinting, and throwing. However, this exercise can cause injury if done incorrectly. Michael Hales from Kennesaw State University in Georgia said that the two greatest problems during the conventional style deadlift is excessive trunk lean and premature knee extension at the start of the lift. Most lifters find it easier to maintain a safe spine position during the sumo style of deadlifting.
The choice of deadlift style should consider the athlete’s body type. For example, those with long torsos and short arms might prefer the sumo style, while those with long torsos and long arms might be more successful with the conventional technique. Done incorrectly, deadlifts can potentially cause serious injury. Seek the advice of an experienced coach before doing this lift. (Strength and Conditioning Journal, 32(4): 44-51)