If you would like to build more strength, size, and muscle. Here are some quick tips:

Tip #1: Keep Your Muscles In Tension 100% Of The Time For Every Rep You Do While Lifting Weights.

Example Exercise - Bicep curl: 

1. Starting Position - Pick up the weight, Lift it slightly so your bicep starts to contract this is where your starting point to the lift is.
2. Lift the weight up as quickly as you can in control using good technique.
3. Lower and Repeat lower the weight slower with control, don't relax your bicep or rest during the rep or set. So when you lower the weight keep you arms slightly bent so the bicep will stay engaged rather that extending the arm straight and having the forarms and shoulders take over more, by doing this you can hurt your bicep and can cause muscle damage and making your bicep weaker, I see people do this at the gym but hey, maybe that's what they want to do, but this exercise and type of training I'm talking about is for power, strength and muscle. As you lower the weight you arm will gather energy for the contraction at the starting position.

SAFETY NOTE: While lifting weights if you keep the muscle in tension using good technique and control you reduce risk to injury.

SPEED BENEFIT: "You can rep as fast as you like while keeping the muscle your working on in tension, with control and good technique of course, so for althetes, power lifters, strength trainers, and even bodybuilding this is key."