Weight Training Guidelines
While no pain, no gain" may be a catchy advertising slogan, it is false and dangerous advice when applied to strength training. Always take care and listen to your body when you start any new exercise program. Start slowly, move slowly, and increase weights and repetitions only gradually. You will be amazed at how quickly a few repetitions with lighter weights or small resistance will have a cumulative effect as your muscles strengthen.
Take a little time to warm up with breathing and stretching (even some enjoyable dancing!), especially when you are working out early in the day. In the early stages keep your focus on the technique and precision of your exercise, rather than the number of repetitions, and practice breathing thoroughly. Don't exercise for more than one hour, but if you feel "spent" don't go on, even if you've only been exercising a short time. Stop and rest.
Beginners will do well to abide by the American College of Sports Medicine's recommendation for eight to ten repetitions of eight to ten exercises, at a moderate intensity, two days a week. Allow your body to rest and rebuild for one to two days between workouts.
Get some guidance. Especially when using weights and other forms of resistance equipment, it is important to learn a few things before you plunge ahead and overdo it, a common way to invite injury. Your local YMCA or fitness center probably offers classes or the advice of a professional trainer. Your coach or trainer can advise you about how and when to intensify any workout by first adding sets of repetitions then increasing the size of weights.
You should also combine your strength-training routine with regular aerobic exercise.