Before learning how to make your muscles bigger, you should understand how a muscle actually gets bigger.
Let’s use your biceps—the muscle group on the front of your arms—as an example. Like all the other muscles in your body, this muscle group is comprised of tightly woven bundles of muscle fibers, which are comprised of muscle cells.
When you require your biceps to produce a force, such as lifting a couch, most of those muscle fibers in your biceps are exposed to tension, especially if your couch has a fold-out bed hidden inside. The tension from the weight of the couch stretches the fibers and causes tiny tears in them. When the cells in your muscle fibers sense this trauma, they begin to rally the muscle-building troops from your body to repair the tears.
These muscle-building troops include hormones, growth factors, and white blood cells, and working together, they not only repair the muscle fibers in your biceps, but they also increase the size of those fibers and the strength of the nerves that activate them, so that next time you lift a couch you are better able to do so. As those fibers increase in size, the biceps grow, which is precisely why you do not want to challenge a moving-van employee in an arm wrestling competition.
Believe it or not, there are better ways to make your muscles grow than by simply lifting the occasional couch. By working with certain exercises, weight, sets and repetitions, you can stimulate much more trauma (and subsequent growth) than the average furniture re-arranging activity.
The trick to building muscle is to adequately stress the muscle, allow the muscle to recover while eating enough healthy food to feed the new muscle, and then repeat! The best exercises for full body muscle growth are exercises that require you to use multiple joints. For example, a combination of squats, cleans, dead lifts and bench presses is very effective at helping your entire body to get bigger. I personally added nearly 20 pounds of muscle to my body by using these exercises during college, and because of that, I looked very good in t-shirts and was also very good at lifting couches.
Dr. Randhir Hastir