Learn exactly when you should be lifting light, heavy or moderate weights - http://athleanx.com/x/step-by-step-workout-plan Some people think that heavy weights is all you need to lift if you want to get big and that would be a big mistake! If you want to build ripped, athletic muscle and size you have to lift in more than just one rep range...including lifting light weights. In this video I show you the top 5 reasons you need to lift light weights in order to build the most well rounded physique. Of course you have to lift heavy as well, and I already did a video on the topic called the top 5 reasons you need to lift heavy. Be sure to watch that in addition to this one to see how to attack both training variables. Lifting light weights can build muscle but you have to take them failure. If you lift light weights and don't take your sets to failure then you are likely just wasting your time in the gym. Unless your goal is to stimulate blood flow or you are recovering from an injury, this type of sub maximal lifting will simply not be enough to create overload needed for growth or improvement. Additionally, light weights allow you to do many of the best set intensifying techniques. Things like drop sets, run the rack sets, burnouts and more all utilize lighter weights (dumbbells or bars). If your weightlifting workouts are not including these types of set extending techniques then you likely are not pushing your body hard enough to see optimal results. Even the muscle fiber types that are engaged with lighter weightlifting is changed depending on the load used. The type 2 a fibers are preferentially used when the weights cause you to fatigue or reach failure in the 20, 25 or even slightly higher rep ranges. The smart trainer will be sure that when you perform your workouts that you are performing some of these high rep workouts along with your lower rep workouts for the most well rounded development. For a complete program array that uses workouts incorpating high reps, low reps, and moderate reps to help you build the best athletic body, be sure to head to http://athleanx.com and check out the various workout options at your disposal. For more videos on how heavy you should be lifting to build muscle, as well as when the best time to use high rep training and workouts is, be sure to subscribe to our channel here on youtube at http://youtube.com/user/jdcav24