I was told you should do some cardio before you lift just to get you heart rate up ( blood pumping). I can see how this would make some sense to "warm up". I also heard people say to do stretching(also heard negaatives on streching before)

But I was also thinking your muscles store a certain amount of energy in them then you have your carbs that your body burns and fat, but those aren't avaible instantly like that stored in your muscle. So wouldn't burning energy be counter productive since you will get genreal muscle fatigue with a longer routine.

So should I do like a 10 min jog before my lifts to warm up, or just go in and start pumping iron.... I used to do 15 min cardio before but I now have just gone straight to lifting and do a "practice set of like 33% wieght to practice form and "limber up" real fast. So far haven't felt a diffrence in strenght with my lifts not warming up.

how you going m8, im a bodybuilder from Australia, if u train legs its a good idea to do a 10 to 15 min brisk walk before u train, other wise u wont to do the compound moment for whatever body part your training at light weight, with perfect form for the first 2 - 4 sets for your whole workout, then get into your working exercises, its also a good idea for the first rep of your exercise to be light and perfect, just so your body gets into the motion of the movement, if your unsure of perfect form, ask one of the guys at your gym, or check out bodybuilding dot com video library
hope this helps m8

As the above poster said, walking prior to a workout is a good idea. It'll warm up your muscles and decrease your risk for injury.

With regards to stretching, only do dynamic stretches (ie bodyweight squats, lunges, etc) before a workout since static stretches (most commonly known stretches) can increase your risk for injury

x2 on the dynamic stretches.

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