Muscle vs strength; this is a topic that has graced the fitness scene at almost every stage of its development. Some of you, upon reading the heading, may wonder, 'How can you build strength without building muscle?' You may look to strength icons like Bruce Lee or Joseph Greenstein aka The Mighty Atom to found your question. They developed immense functional strength without muscle bulk. I will explain further in a bit. Even more of you may wonder, 'If you're building muscle, aren't you building strength?' A lot of factors play into strength. Thus, the answer is yes and no; once more, I'll explain this later.
First, let's address the controversy. This is an topic that generally becomes an argument of bodybuilders vs. powerlifters, weight trainers vs. gymnasts, so on and so forth. This article will not seek to uplift, shoot down, or otherwise any strength profession. To attempt to do so would undermine the work of many great innovators before me. I'm writing to focus on the physiology. The process of muscle growth is one that is not entirely understood at a molecular level.
Muscles grow is a result of hypertrophy, or an increase in the size of the muscle tissue. The myofibrils in the muscle strengthen by holding more protein and growing in thickness. This results in increased strength, and a bit of size increase. The sarcoplasm, fluid containing glucose for extra energy, around the muscle contributes to muscle size, with no strength contribution. The nervous system is often neglected, but it plays the biggest role in increase your strength and size. When you exercise hard enough to fatigue your nervous system, your body releases human growth hormone and testosterone to increase bone density, tendon strength, and muscle growth. Taking this into account means that your strength could increase in a number of ways.
One way is that you increase your muscle mass. With more muscle to contract, or larger muscle cells, your strength increases. You improve your ability to do strenuous tasks because the increase in muscle allows more oxygenation and blood flow to that area. Consistent training to gain muscle mass can also improve your vascularization, or forming of blood vessels. This is certainly an indicator of an increase of strength. However, exercises catered purely to muscle mass WILL NOT MAXIMIZE YOUR STRENGTH GAINS. You'll plateau more often and have difficulty gaining strength if your only goal is muscle mass. But this is because muscle mass programs seek to build your sarcoplasm up, which doesn't contribute to strength AT ALL. You'll get some myofibrillar growth, but not as much as if you focused specifically on a strength building program. Thus, building muscle will clearly build you strength, but you have to know whether your training develops MUSCLE or SARCOPLASM. Often, high volume is a good sign, but not a definite sign, that the program isn't catered to real muscle growth. Of course, diet is a huge factor in your muscle and strength gains, so try to eat healthy foods, lots of vegetables, and about 240 grams of protein a day. I hope that answers the second question.
Overall, your muscular strength system is more complex than to be encompassed by an increase in muscle size. If that were the case, strength competitions would be so simple because the man with the biggest muscles would always win. You can build strength in various ways. Let us revisit the earlier image of hypertrophy. Now, if instead of training to increase muscle mass, you sought to increase the strength of your muscle contractions or tendons, you'd surprise yourself and your friends with your strength gains. By improving your control of the muscle you already have, you can increase the control that the nervous system has over that muscle to transfer that contraction signal. Being able to contract your muscles harder means more strength.
You will find that with constant training, you can contract the muscle much harder than ever believed. Furthermore, training your tendons in a manner that will enable them to thicken at incredible rates will give you a stronger band with which to contract your muscles. It's like a bridge; the bridge itself supports the cars, but the bridge supports helps the bridge to carry heavy resistance and transfer shock. Our tendons are the bridge supports of our muscles. The muscle is what contracts, but its strength is contingent upon the strength of the corresponding connective tissue. The stronger and more elastic your connective tissue, the better you can transfer that energy to you muscles and into whatever task you seek. You can train this very well using isometrics, partial lifts, and supports, as well as using compound exercises. That should cover the first question.
The bottom line is that your training should be specifically catered to your goals. Training for muscle mass to gain strength will get you no further than attempting to do vice versa. Of course, either method will show results in the other category, but those results won't be optimal; it'd only be a byproduct of your initial goal. Decide what your goal is, then cater your workouts accordingly.