Chaos
"Explosive" usually refers to the start of a exercise, where the initial thrust of moving a object/weight begins. Like a sprinter exploding off the starting blocks to get his first burst of power, and advantage, in a race. There are three phases of muscle contraction, the first being the starting motion of an object (in the sprinters case, his body/bwt) and the other two phases kick in as the object continues it's travel.
If have ever worked within a Power rack/Cage, than it's possible to set the pins in positions where you can develop explosive power in the normally weaker phases of a exercise. For most, the middle phase seems to give the most problems with the imbalance of weakness. Lockouts are usually the more powerful of the three phases. Chain training helps greatly, as does speed reps, when the idea is to develop the initial explosive, or power thrust, in any lift. Any of these can also be applied to the second and third phases of a exercise, with a little thought and workout planning. Good Luck.
Side Bar: I have use the term "usually" quite a bit since coming on GB. Meaning that there is never a set normal for anyone or anything in lifting. No absolutes, that every one will get the same result when doing the exact same exercise, workout plan or eating habits. Some can do 5X5's, 20 sets per body part, push-pull, SS's, tri sets, quad sets, forced reps, etc and make unbelievable gains. Others might find that any of those protocols would be a disaster for their body's. Some can eat clean and still look like a skinned rabbit. Others eat all the junk food they want and get impressive muscle size and keep low body fat. BB's is really one big experimental lab, on the individual bases, for anyone. But always worth a try, to see what works for you and you only...usually.
Even trainee's respond differently to drugs. Some make almost overnight gains, some after months, may show little or no progress.