Getting bigger and stronger involves three main parts:
To make decent progress, all three need to be taken care of.
The best approach will depend on where you are now and where you want to be at. There is no overall universal best training method or diet that will work for everyone. You need to define your goals, analyze your current state, and then develop a plan from there.
For example, if you are a really skinny 20 year old guy who weighs 60 kg who is trying to bulk up, your approach would be different to that of a 45 year old overweight unfit guy trying to get leaner.
Some of the main competitive sports to do with weights training include:
All of these have fairly specific goals and methods of training:
On the other hand, sports specific strength training is concerned with improving an athlete's performance in their sport (be it wrestling, rugby, rowing, etc). The training may involve a combination of static strength training, explosive strength training, and fitness work. It may use a combination of free weight exercises (e.g. bench press, barbell rows), bodyweight exercises (pull-ups, dips, push-ups, burpees) to achieve this.
My personal goals are to gain functional all-round strength that is useful for sports, and at the same time increase my muscle size and mass, while staying reasonably lean. The advice below is based around these goals.
Too many people dive straight into joining a gym before doing any real research or thinking about their goals. They end up on some crappy cookie-cutter program that relies on machines and end up with average results. Almost anyone will get decent improvements initially even on a terrible training program, but training intelligently will get better results and reduce the risk of muscular imbalances etc.
Get advice from knowledgeable people. Post a thread on the Bullshido Physical Training, Diet, and Health Forum or the Sherdog Strength & Power Discussion Forum. Introduce yourself, your current situation, and your goals. Try to give as much information as possible. If you ask the question in an articulate, polite, and detailed manner you will get better responses. Keep an open mind when viewing the replies.
I highly recommend that you get the book Starting Strength by Mark Rippetoe. It contains a wealth of information on the most important lifts for gaining useful strength, such as the squat, deadlift, bench press, clean, overhead press, and so on, and goes into great details on how to perform the exercises with the correct technique and the anatomical reasons why.
Some other great sources of training programs and workout advice for athletes, particularly martial artists, are RossTraining and CrossFit. I haven't tried them yet but intend to soon.
Here is a 100 word summary of CrossFit (from their website):
Eat meat and vegetables, nuts and seeds, some fruit, little starch and no sugar. Keep intake to levels that will support exercise but not body fat. Practice and train major lifts: Deadlift, clean, squat, presses, C&J, and snatch. Similarly, master the basics of gymnastics: pull-ups, dips, rope climb, push-ups, sit-ups, presses to handstand, pirouettes, flips, splits, and holds. Bike, run, swim, row, etc, hard and fast. Five or six days per week mix these elements in as many combinations and patterns as creativity will allow. Routine is the enemy. Keep workouts short and intense. Regularly learn and play new sports.
I am a big believer in free-weight exercises or bodyweight exercises rather than machines. By this I mean doing proper squats rather than leg press or smith-machine squats, doing pull-ups rather than lat pull-downs, and so on. Unlike their machine counterparts, free weight exercises require some technique, balance, and coordination. You are not simply producing a force, you are balancing and controlling that force.
I believe in focusing on compound exercises. A compound exercise is simply an exercise that works two or more muscles, whereas an isolation exercise is one that only targets one muscle. Deadlifts are a good example of a compound exercise; they work out heaps of muscles. Concentration curls, which only target your biceps, are an example of an isolation exercise.
My reasoning for focusing on compound exercises and free weights over machines is that in any real-world activity or sport, such as when you are tackling someone in rugby, punching someone in a fight, throwing a ball, or moving heavy furniture, your body works as a system with many muscles working in unison. You require balance, coordination, and timing. Compound exercises help this; they teach your body to use muscle groups together to produce useful results. I believe that how you train will affect you perform; that is, if you train your body as isolated muscles then that's how you will end up; you make look big but you will basically be a bunch of individual muscles that can't work together. The major compound exercises also tend to work your muscles pretty much in order of their importance.
For the same reasons that free-weight and bodyweight exercises are good for you, they can be harder to learn and so may seem daunting to a beginner. Gyms around the world are filled with people who either don't know, are afraid of, or too lazy to do the major free weight exercises, and workout endlessly with machines. Don't take the easy option and avoid them! Take the time and do some reading, learn about the techniques, and if you can get a good coach or experienced friend or someone who knows how to do them to show you.
The important exercises that you should focus on include the following:
Isolation exercises such as bicep curls, leg curls, leg extensions, flys, and so on, are inferior to compound movements for strength development. Training in compound movements trains muscle to work in tandem to move greater weights and generate greater strength and power. Isolation exercises do have their place for trying to rehabilitate an injury or for an advanced athlete improving a specific weakness. They may also be used a lot by bodybuilders who are simply trying to increase the size of their individual muscles and don't care if it is essentially useless extra weight. By and large, isolation exercises should be avoided by any athlete for most of their routine.
A workout program is basically a workout plan that structures when and how often you go to the gym, what exercises you do, how those exercises are split up over multiple days, how many sets and reps you do on each exercises, and so on.
You may want to start by reading the Guide to Novice Barbell Training (aka the Rippetoe Starting Strength FAQ) on the Bodybuilding.com Forums.
To get an idea of some of the various types of routines out there, check out the post The Main Programs Floating Around Basically Sketched Out on the Bodybuilding.com Forums.
With both full time work and a lot of martial arts training, I usually only manage to get in two or three gym sessions a week. My workout as of August 2007 is structured as follows:
Day 1
Day 2
Day 3