One thing I want to bring up.....again,.....about this whole "warming up" thing..... In my opinion, it seems many people concern themselves in a convoluted way with "warming up" the muscle(s) they're about to exercise. And that is all they think about.
I want to make two points:
(1) As 3 brought up in the thread cursor posted a link to, also of very vital concern is the importance of preparing the connective tissues for the impact of
weight training, and not just hitting them bluntly with intense overload without any proper preparation. This extends beyond the "muscle" and delves into the importance of how the connective tissues must be "warmed up" and prepared, the ancillary, stabilizing, antagonist muscles....even your skeletal system must at the very least be "alerted" to the fact that......somethings coming!
(2) A "warm-up" in the form of
cardiovascular exercise.....are we forgetting a very important muscle involved regardless of what muscles we're cognitively contemplating to train,..... our heart. Your lungs, your vascular system, your brain,.....It really is important to think about how during these 15 minutes of you doing a moderate warm-up on the bike, treadmill, eliptical, or whatever,....you're redistributing, or preparing for redistribution, of hormones, gases,....blah blah blah....and I still am ('spect I always will be) amazed at how few people are either so overly dramatic at how 15 minutes would be such a "waste of their precious lifting time," assuming it invaluable, or neglecting how 15 precious minutes of non-lifting activity (that's the key, folks, for those who are skimming the reading) not only physically benefits your body and will benefit your lifting that day, but also, it psychologically, mentally, buffers you, taking you "FROM" where you've been, and gets all of you, ready to leave what was behind, and get geared for the physical demands, and how everything in your body was functioning, will now be needing to function differently.
Simple....