An overview of resistance training: exercise to build muscle

Resistance training, strength training, and weight training all mean pretty much the same thing. While aerobic, or cardio, exercises boost your heart rate, resistance training works to build muscles, forcing them to contract against some kind of external resistance. Depending on how you perform the exercise, it increases the muscle's strength, mass, tone, and/or endurance.

You can apply the resistance with various kinds of weights or weight machines, with resistance bands or tubes, your own weight (as in pushups or pullups), or everyday activities (picking up a sack of groceries or bags of compost from the garden center).

Weight training is not the same thing as weight lifting, a competitive sport, although some of the weight lifters' moves may be a part of it. Your objective is building muscle for total body fitness, not lifting more than someone else does. Your routine will combine aerobics, resistance training, balance exercises, and stretching to attain and maintain optimum fitness.

In order to get any benefit, you must train consistently over time. Eventually, your body will accommodate itself to your routine. At that point, to get any further benefit you must increase the workload by some combination of working with heavier weights and repeating a particular move more times (or, as the jargon goes, getting more reps).

If your primary objective is to build muscle strength, choose a large enough weight that that you can do only 5-7 reps without becoming exhausted. If your primary objective is to lose weight or build endurance, use less weight so that you can do 12-15 reps. In any case, you should find the last rep difficult to complete. A routine of 8-11 reps will combine aspects of building strength, tone, and endurance.

Once your starting point becomes easy, you need either a heavier weight, additional reps, or multiple sets. That is, if you can easily do 15 reps and choose not to increase the weight, pause for a while (maybe a minute for endurance training, more for strength training) and immediately try to do, say, 10 more. When you can easily do two sets of 15 reps, do a third set.

There is no easy formula to determine how much weight to work with when you first start out. Pick something and try it out. If your goal is to build muscle for general conditioning and you cannot manage at least 8 reps, it's too heavy. If you can easily do more than 15, it's too light.

Do not work the same muscle group two days in a row. The muscles need time to recover from your workout. If you concentrate one day on lower body muscles, you can work just as hard on upper body muscles the next day, but you must give your muscles time to rest.

Any good gym will have a variety of dumbbells, barbells, kettlebells (collectively free weights), and weight machines. Using free weights requires balance and coordination, which everyone needs to develop. Free weights also involve more muscles, as you don't have the machine doing some of the work for you.

Weight machines typically work to build one set of muscles. Machines for the arms will typically work either the biceps or triceps. Similarly, there are only a few kinds of machines for the back, chest, shoulders, etc. Leg machines have the greatest variety, working on quadriceps, hamstring, calf, thighs, and glutes.

You should work with both machines and free weights. Each offers opportunities to build muscle that the other doesn't. If your gym has different brands of the different kinds of weight machines, try to use them all. The right weight for one of them will not necessarily be right for another, because they will work the muscles from a slightly different angle. You will need to use a smaller free weight than what you can do with a corresponding machine exercise.

Remember that you don't need weights for resistance training. You can use resistance bands of various kinds and medicine balls of various sizes to perform a variety of workouts. You can also use your own body weight to build  muscle. These kinds of exercises (push ups, sit ups, crunches, etc.) complement weights much as free weights and machines complement each other.

Whatever equipment you use, you must learn proper form and technique, either from lessons with a certified personal trainer or from a strength/resistance training video. At best, poor technique will impede your progress. At worst, it can cause serious injury. You can also find a great deal of information (and, alas, misinformation) online. Here is a particularly comprehensive article.