You may think that you're in good shape, but if your bodybuilding routine doesn't include core strength training, you are missing out on something that will improve your overall fitness.

The "core body" refers to the muscles of your torso that help you maintain balance and posture, whether you are running, standing or sitting. Strengthening these muscles will improve your ability to perform your specific, specialized exercises for your arms and legs.

Fitness balls will help strengthen your core muscles. They are fun to use, but that doesn't mean they don't work. If you are new to doing crunches on a fitness ball, you will be surprised at how much more your abdominals are engaged compared with standard crunches. Sitting on a fitness ball engages your abdominal and lower back muscles; they're working hard just to keep you from falling off! But you'll strengthen your core even more with some basic ball exercises.

Start by sitting on the ball and roll back so the ball is centered under your shoulder blades and your head is dropped back towards the floor behind you. Place your hands on your ears and curl up into a sit-up. Release. Start by repeating 10 times and work up to 30. If you are new to using a fitness ball, sit on the ball with your legs wide, between three and four feet. Once you've mastered that, move your feet in so they are shoulder-width apart.

Many gyms have fitness ball available, but if you have a workout space at home, consider buying your own from any sporting goods store or sports equipment web site.

You've been weight lifting for years, so you know it all, right? Maybe, but sometimes reviewing the basics helps get you back on track after an injury or if you feel like you're going through a training rut.

During your next weight lifting workout, keep these "Basic B's" in mind:

• Breathing. Believe it or not, holding your breath while lifting weights may cause your blood pressure to spike. Remember to exhale as you lift the weight, and inhale as you lower the weight and you can help your muscles work more efficiently.
• Balance. You may want to focus on building up your chest and shoulders, but you'll get the best overall results if your weight lifting routine includes all the major muscle groups. That includes the abs, quads, and hamstrings, as well as deltoids, pectoral muscles, and biceps. Don't lift the exact same weights on consecutive days. And balance also means using proper technique. If you can't maintain good form, reduce the weight. If you have been training hard, try a session using slightly less weight than usual. You will still burn calories and get a workout but you won't contribute to a potential injury.
• Budget. As in, budget enough time for your workout. If you are rushing, you are less likely to use proper form and you are more likely to get injured. And factor in time for a short warm-up or cool down (walking or biking to the gym counts!)
• Bring a Buddy. If you need a spotter, ask for one. There's no reason to risk injury, and if you don't have a training partner, ask a staff member at the gym to spot you for your toughest exercises.

Strength training is very important when you're trying to lose weight--even if you're not interested in becoming Mr. or Ms. Universe. Strength training not only tones your body, it boosts your metabolism so you will burn more calories at rest.

Here's how: When you exercise regularly, you build up the proportion of muscle in the body compared with fat. Unfortunately, lean body mass decreases with age in everyone, regardless of how fit you are. If you don't do anything to preserve your muscle, it will be replaced by fat. If that's not motivation for strength training, what is? But remember that you don't have to spend all day lifting weights. One or two sets of 10 to 12 repetitions of moderate weight will tone your muscles and improve your posture and overall physique.

As you become more experienced, or if you are strength training as part of a cross-training program to keep you fit for other sports, strive for balance between opposing muscle groups. That means you should lift similar amounts of weight for opposing muscle groups, such as the biceps and triceps, or the quads and hamstrings. Some groups may be stronger than others, and that's ok. For example, if you are a runner, the weights you are lifting with your hamstrings may feel easy. Because your hamstrings get plenty of exercise from running, it is better to lift less with them than to lift more with your quads to achieve balanced muscle strength.

Include opposing muscle groups in your strength training sessions. In half an hour, you can fit in 2-3 sets of 10-15 repetitions for a few key muscle group pairs:

• hamstrings/quadriceps
• adductor/abductor muscles (inner and outer hip)
• calf muscles
• biceps/triceps
• shoulders

You have heard of power lifting and maybe seen power lifters at your gym. But is there a place for power lifting in your fitness routine? Or are you looking to break out of a rut and try something new?

Some basic power lifting points may pique your interest:

• Power lifting is unique. The difference between power lifting and standard weight lifting is that competitive power lifting, as it is performed in the Olympics and elsewhere, involves three moves: the deadlift, the squat and the bench press. The winner is the one who lifts the most weight--it's not the size of your muscles that counts, it's the strength. The goal is to lift the greatest amount of weight for one repetition with good form. A "good" lift meets the criteria for established safe and proper technique.
• Gearing up. If you want to get into power lifting, be sure you have a good lifting belt, as well as a bench shirt, which is a customized, tightly fitted shirt that helps protect the shoulders. You should seek out a specialty retailer for this shirt and get measured so it fits you snugly. Knee and wrist wraps are also important for support when you are power lifting.
• Training right. Power lifting can be a great way to add variety to your weight lifting or bodybuilding workouts, even if you aren't entering competitions.

A sample power lifting routine involves a cycle starting with 5 sets of 10 repetitions at an intensity of about 60 percent, and then gradually reducing the repetitions while increasing the weight over 12 weeks, so you end up doing 2 repetitions at 99 percent of your maximum effort.

When considering a trainer, keep the Four E's in mind:

1. Experience. Find out how long a prospective trainer has been in business, and ask about areas of specialty. If bodybuilding is your goal, choose a trainer with experience in this area. If you are a runner or cyclist looking to improve your speed, try to find a trainer who has coached runners and cyclists.
2. Education. Your trainer should have a current certification from a reputable fitness organization.
3. Emergencies. Ask whether your trainer is up to date on his or her certification in some basic first aid and/or CPR.
4. Explanation. Be prepared to explain your goals to a prospective trainer so he or she can offer guidance and help you track your progress, and be sure that your trainer explains the benefits of your exercise plan and shows you the correct techniques.

A good personal trainer will listen and understand your goals and develop a sensible, realistic training plan. If you feel intimidated or uncomfortable with a trainer, it's not a good match. Trust your instincts and don't hesitate to switch to another trainer if you aren't satisfied. If you have prepaid for a set number of sessions, you may be able to get a partial refund. Some gyms allow you to transfer sessions from one trainer to another within the same gym. Policies vary, but you won't know unless you ask.

Some people want to build strength without bulking up. But some of us do want bigger, as well as stronger, muscles. Fortunately, there are specific programs for bodybuilding workouts and gaining mass that can help you reach your goals. If you are a bodybuilder who wants to gain mass, you are going to need a two-pronged approach: work out more and eat more. But before you guzzle down that beer and load up on greasy foods, know that quality and quality are both important.

First, the workouts. To build muscle, bodybuilding experts recommend training hard 4-5 days each week. This plan gives the body time to recover. Complete the majority of your exercises at 80 percent of your maximum effort. Save the 100 percent efforts for competitions (if you compete) and times when you feel energetic and want to test your progress. Follow an organized plan of exercises, although you can mix up the order for variety. Just be sure to include exercises for each major muscle group twice a week.

Second, the food. Bodybuilding workouts to gain mass need fuel. Get plenty of high-quality protein from red meat, poultry and fish, and from dairy products such as milk, cottage cheese and eggs. Choose pasta, potatoes and rice for most of your carbohydrates because they will provide energy for workouts, but burn off quickly and are less likely to be stored as fat. Don't gorge yourself. Increase your calorie intake by eating smaller amounts throughout the day to maintain energy and gain mass through your tough workouts.

Although they aren't essential, many bodybuilders consume dietary supplements to promote gains in muscle mass. If you want to take a supplement, do your homework and don't be mislead by products that make unrealistic claims. That said, many safe supplements exist, and some also contain nutrients such as omega 3 fatty acids that have health benefits beyond bulking up.