Strength training is the name for any exercise that uses resistance weight to work a muscle or a group of muscles to the point of fatigue. As the muscles recover, they build strength and endurance.

The University of Michigan Health System gives the following recommendations before starting a strength training program:

• Eat right. The body does not respond well to a good workout coupled with poor nutrition.
  
  
• Change the workout. Vary the (reps), set and types of exercise to prevent progress from stalling.
  
  
• Use good form. Do not exceed a weight limit that causes poor posture. Exhale while lifting a weight, inhale when lowering and never hold the breath.
  
  
• Exercise the entire body. Do not undertrain one part of the body and overtrain a different part. Train opposing muscles equally (e.g. both biceps, triceps or quads).
  
  
• Be realistic. It is best to plan to lift 2 days a week and actually do it, than to plan to life 4 days and find it hard to meet the goal.
  
  
• Don't overtrain. The body cannot recuperate between workouts if the exerciser overtrains. Signs of overtraining include headaches, nausea and rapid heart rate upon waking up. When feeling run down, take a break for one or two days.

Strength training offers many healthy benefits when performed properly. It increases bone strength, reduces the risk of osteoporosis, improves joints stability and helps burn fat by raising the metabolism. Other benefits gained with strength training include improved insulin sensitivity, lower cholesterol levels, lower blood pressure and improved mood.

The key to achieving these benefits is to know how to increase weight safely while continuing to maintain good form and posture. Put simply, as the exerciser gets stronger, he or she must increase the load on the muscle to continue to achieve a strength-building benefit. When able to perform a certain number of repetitions in a set easily, it is time to increase the weight again.

It may be tempting to leap to a higher weight – moving from 25 pound plates to 45 pound plates for instance – before the body may be ready. Rapidly increasing training weight gives the feeling of accomplishment and progress.

However, increasing weight too quickly can be dangerous and counterproductive. Maintaining the proper form is crucial to preventing muscle strain, and it is the first thing sacrificed by attempting to lift weights that are too heavy. Furthermore, increasing weights or resistance improperly may cause the exerciser to be too sore to continue the strength training program.

The old adage “no pain, no gain” is misleading and potentially dangerous. By increasing weight or resistance gradually and safely, people can minimize soreness while maximizing the benefits of strength training. It is normal to feel some muscle soreness after a strength-training workout. However, soreness lasting more than 2 days after a workout means that the muscle has been over-worked.

On the other hand, people should not be afraid to challenge themselves. Working out at the same weight for too long reduces the benefits of strength training and can be boring. This is a major reason why people stop lifting weights.

Increasing muscle strength requires regular strength training, adequate rest and proper nutrition. Experts recommend working out at least two to three times a week, with a minimum of 48 hours in between to allow the muscle group to rebuild.

Terms to become familiar with are:

• Rep. Short for repetition. A rep means the range of motion has been completed once for an exercise.
  
  
• Set. The number of reps of a particular exercise that should be done before resting or moving to another exercise.
  
  
• One rep max (1RM). The maximum amount of weight a person can lift for a given exercise for only one rep.

Workouts are divided into upper body and lower body exercises. Lower body exercises consist of squats, lunges, calf raises, leg curls, leg extensions, crunches and sit ups. Upper body exercises include crunches, situps, bench presses, bicep curls, triceps extensions and pulldowns. Both types of exercises can use free weights, weight machines or the weight of the body.

During a workout, each repetition should be performed with good form. Starting out, be conservative when choosing the right weight. People should not start with a weight that may tire them before completing between eight and 12 repetitions.

Depending on a person's fitness level, he or she might begin with just one set, adding another one after three to four weeks (about 6 to 12 workouts). Generally, 3 sets of 8 to 12 repetitions is a good goal to shoot for. Keep a record of the workouts to show progression. This is also a great way to stay motivated.

Progressively increase weight when it becomes easy to perform 15 repetitions. For the upper body, increase weight 3 to 5 pounds (1.4 to 2.3 kilograms). For the lower body,  increase in 10-pound (4.5 kilogram) increments.

Remember to lift in a slow, controlled manner, and go through the complete range of motion available at each joint. If unable to finish a repetition in good form, do not cheat by trying to “throw” or jerk the weight up.

Muscles should be allowed to rebuild over at least 48 hours; do not train the same muscle group two days in a row. Overtraining can actually cause muscles to decrease in size and can easily lead to injury. Finally, a person should have a spotter who can offer assistance and encouragement.

Always consult a physician before beginning any exercise program. Furthermore, people may wish to consult a certified fitness trainer, who can design an exercise plan that is most effective for them.