Unlike aerobic exercises, resistance training (weightlifting) doesn’t work the entire body at once. Instead, you need to do different exercises that target specific muscle groups.
If you go to a gym, you’ll find machines designed to help you do this. But you can also do resistance training at home, using basic exercises like push-ups and pull-ups and possibly some hand weights, or dumbbells, which you can get from any sporting-goods store. (If you don’t want to buy dumbbells, you can improvise by using everyday objects like milk jugs filled with water or sand.) How much weight you need depends on what you can comfortably lift, and that will vary from exercise to exercise, so you’ll need more than one set of dumbbells. Sets of 3, 5, and 10 pounds should do the trick.
Be sure to follow these basic principles when weightlifting:
Lift to fatigue. Rather than building endurance, with weightlifting you want to quickly make muscles so tired they just can’t do much more. As a rule, you should have enough resistance during any exercise to make muscles feel fatigued after 8 to 12 repetitions. At the beginning of your program, start with light weights that you can easily lift for 12 repetitions until your muscles get accustomed to being worked.
Move slowly. Avoid quick, jerky movements with weights, which can stress muscles, ligaments, and joints. Slow and controlled movements ensure that you’re working muscles at every point in your range of motion and not letting momentum do any of the work for you. A general guideline: Take two seconds to lift the weight and four seconds to let it down again.
Breathe evenly. Don’t hold your breath when lifting weights — you need to keep oxygen flowing to working muscles. Breathe out when you lift and in when you let the weight down.
Go from big to small. Work large groups of muscles like the chest, legs, and back first, saving smaller muscles, such as the biceps and triceps, for last. That way, you won’t tire smaller muscles that support the bigger muscles during their workout.