Did you know that the 2 most important factors when it comes to gaining muscle mass from weight training is how much weight you lift, and the intensity in which you lift? Intensity means everything when you're working out.It's true, every single time you wrap your hands around a weight, your goal should be to use the most intensity possible. By using more intensity, you're more likely to lift more weight and have the mindset needed to progressively increase your overload to that muscle.Always remember that muscles have no reason to grow. Your body does not need extra muscle for its day to day activities. The only way to gain muscle mass is to lift more weight. See, this overload to the muscles is what causes the stress and strain that forces them to get bigger.When you lift heavier weights, you actually cause muscle fiber damage. When you lift, you're producing tiny microscopic tears to your muscle tissue.Now, providing that you eat right and give your body the nutritional support it needs, your body will repair that muscle tissue by adding extra muscle tissue to make it bigger.That's right, you actually increase your muscle mass so that your body can handle the extra weight you're going to use again, next time. Your body is an amazing machine.It will respond to this heavy weight by adding more muscle mass, so it can handle the extra strain and stress you're going to keep putting on its next workout. If you keep lifting heavier weights, and use more intensity... your body muscle prepares itself by adding enough extra muscle fiber to handle this extra weight.This overload and stress to the muscle is what causes muscles to get bigger. And one way to keep increasing the amount of weight you lift is to always try and increase the intensity you use. Think about it. If you're in the gym, and you're just walking around tired, sluggish, and not too energetic... when you walk over to that barbell, you're probably not going to have the best lift.But if you're focused, you pump yourself up, you get energized and get yourself intense and into a frenzied focus-the minute you walk over to that weight and wrap your hands around that bar, you're probably going to have a better lift and either lift more weight or get more reps.This is where muscle gains happen. If you keep lifting more weight, or you keep increasing your reps, this extra stress on the muscles is why they will get bigger, in order to handle the extra weight for the next session.And in order to lift more weight, or get more reps, you need to FEEL more intense and more energized so you can get that extra rep, or add that extra 5 pounds.This intensity will always help you lift more weight and increase the overload to the muscles, so they get bigger. Or, the intensity will help you squeeze out those extra reps that you otherwise wouldn't have gotten. And this too will help increase the stress to the muscles... causing them to grow.Look, if all it took to build muscle and gain a lot of strength was just simply lifting weights and working out, without using any intensity or without always trying to lift more weight, every single person you see would have a body like a Greek god.But not everyone has the same build. And that's simply because it all comes down to how hard you are working out, the intensity you use, and how well you try to outdo yourself each and every time.If one lifter just does light sets, doesn't use intensity, and never tries to keep lifting more weight or get more reps, that person will not change much, in the way of muscle or strength.But if you're always striving to outdo yourself, and lift more weight than before, or get more reps than you did before... this extra intensity makes all the difference in your results when working out.The bottom line is, when it comes to working out and getting results, it all comes down to " you get back what you put in."If you go to the gym and just go through the motions and barely break a sweat, you're not going to get nearly as good results as someone who busts their butt, lifts with the most intensity and energy, and tries to lift more weight or get more reps each time.This constant intensity, and the will to outdo themselves each and every time they step foot in the gym... this is where the real gains happen.So, if you want more results from the time you spend in the gym working out, focus on increasing your intensity, so you can lift more weight, overload the muscles more, get more reps each exercise, and you'll build more muscle and strength as a result.Intensity is the one thing that separates average gains from amazing gains. And I'm sure, if you're like most lifters, you'd rather see the amazing gains. Focus on establishing a well-oiled routine that includes a preworkout supplement, which will help you get that pump and intensity that you need.The next time you are working out, make it a goal that each and every rep and set you do for each exercise is using the most intensity possible, and you'll surprise yourself with the results.