Can you knock off eight miles on the track or an hour on the bike, but struggle through a few pull-ups? Despite your commitment to fitness, your workout is likely missing something. You know what I'm talking about. We spindly-armed runners, cyclists, and ]]>treadmill]]> hounds are so smitten with our lung capacity that we tend to neglect an essential part of total fitness—strength training.

These words may send scary visions of 26-inch thick necks dancing through your head, but you need not spend hours in the gym getting "pumped up" to enjoy the benefits of weight training.

"With just two sessions per week, you can make significant gains in strength, power, and overall fitness," explains Michael Wood, CSCS, a certified strength and conditioning specialist and director of the Sports Performance Group in Cambridge, Massachusetts.

The Benefits

Regular weight training makes you stronger and we're not just talking about bulging biceps. Weight training strengthens bones, ligaments, and tendons as well as muscles, all of which translate into improved balance, greater power, quicker recovery, and a reduced risk for injury.

In fact, "by performing only aerobic exercise, you could be setting yourself up for an overuse injury," cautions Nicholas DiNubile, MD, orthopedic consultant to the Philadelphia 76ers and the Pennsylvania Ballet. " ]]>Running]]> , for example, works the back of your legs—calves and hamstrings—but tends to let your quads and upper body off easy. By strengthening all the major muscle groups, you can avoid an imbalance and reduce your risk for injury."

Get Hard Core

Wood, who also conducts research for the Tufts University exercise physiology laboratory, recommends building strength from the inside out. "Your trunk, abdomen, and back make up your 'core strength,' which is the origin of most of your power, agility, and balance. Therefore, a strong, solid core is essential before outer, sport-specific strength can be developed." The basics, such as crunches, lunges, and squats, help build this core.

Weighing the Options

Machines, dumbbells, balls? Which is right for you? All of it. Vary your workout to avoid boredom and maximize results.

Weight Machines
Machines are the best way to begin.

"The machine guides your movement and keeps you in one plane of motion, leaving less chance for error and injury," explains Wood.

Novices should start with light weight to avoid overtaxing the muscles and to develop a consistent routine. Lift one day per week for the first few weeks, then add a second session. Start with one set of a weight you can lift for 8-10 repetitions and increase to 2-3 sets. Once you have established a regular routine, increase the weight by 5-10% per week, strive for a weight that you can lift 8-10 times for 2-3 sets. By the last repetition, you should be tired and unable to do another, yet still in good form. Do this by lifting and lowering slowly, don't let gravity pull the weight down for you.

Free Weights
"Once you start building muscle, your body adapts quickly," explains Wood, "and you need to challenge your muscles with different modalities and heavier weights."

Free weights add this new dimension of difficulty. Now you have to perform the desired movement while keeping your whole body stabilized. The result is that more muscles are engaged and you get a more efficient workout. However, as Dr. DiNubile points out, "with free weights, it's easier to cheat—to push a weight too fast and use the momentum instead of your own power." To avoid cheating, form should be slow and controlled, not bouncy or jerky. Lift for 3-4 seconds, pause for 1 second, lower for 3-4 seconds. "Never sacrifice form for weight," advises Dr. DiNubile.

Resistance Bands
Traditionally used only by physical therapists, these portable, multi-colored, oversized rubber bands have recently worked their way into gyms, homes, and suitcases. Wood stresses that they are best used as an adjunct to weight machines or free weights since the exact resistance of the bands is difficult to determine and they are limited by the maximum resistance they provide.

Medicine Balls
These balls, ranging from 2.2 to 20 pounds can add a significant amount of resistance to your lifts. Check with a strength and conditioning specialist or a certified athletic trainer for the best way to use them. For instance, do sit-ups with your arms stretched straight above your head, holding a medicine ball.

Stability Balls (or ]]>gym balls]]> )
Much larger (and lighter!) than medicine balls, stability balls are meant to be sat on. More specifically, balance your butt and lower back on the ball with your feet planted on the floor. Then, lean back and do sit-ups or upper-body free weight exercises. All the while, your body uses more and different muscles than are normally engaged. And these are the core muscles—abdominals and lower back—that are key to overall strength and power.

What about when you're stranded on a desert island with no equipment, well, there is one thing you can do: drop and give me 20! By using your own body weight as resistance, you can get a significant workout doing push-ups, sit-ups, chin-ups, lunges, squats, and triceps dips. Do jumping jacks before and between each exercise to keep your heart rate up.

The fitness industry is constantly developing new tools and techniques to change up your routine. Keep an open mind to trying new activities or equipment but also be wary of the junk that may also come out. Ask a trusted fitness professional for advice on new equipment or exercise options.

Feeling the Burn

Although some muscle soreness is normal the day after lifting, weight lifting injuries are rare. However if you experience any of the following, rest a few days and see a sports medicine professional if it doesn't resolve:

  • Soreness that lasts more than two days and limits activity
  • Pain worse on one side than the other
  • Pain occurring in the joint, not in the muscle
  • Swelling or bruising
  • Loss of range of motion or mobility in the joint

Putting It All Together

"A complete, balanced program incorporates cardio work, strength training, and flexibility exercises," explains Dr. DiNubile. It may sound difficult to fit each of these into your week, but a strength and conditioning specialist or personal trainer can help design a weight training program to develop your core as well as your outer strength. Before you know it, you'll be jumping higher, running faster, pedaling harder, and looking and feeling stronger and more confident.

The Strength Circuit

Wood recommends the following program:

  • Three days of aerobic exercise (one hour)
  • Two days of circuit weight training (30 minutes of cardio followed by 30 minutes of strength training)
  • Two days of rest
  • Stretch before and after every workout.
  • Keep your heart rate between 70-80% of maximum for the entire hour by moving quickly from one exercise to the next.
  • Hit each of the major muscle groups and don't work the same muscles on two consecutive days.

Here are the details of the strength circuit: 8-10 repetitions of each exercise. Repeat the strength circuit 2-3 times within the second half-hour of your workout.

1. Step-up —Holding dumbbells, stand on an 8- to 16-inch platform (about the height of a park bench). Step down with the right foot, pause, then step back up. Do 10 reps then switch legs.

2. Pull-up —With your hands wider than your shoulders on the bar, pull yourself up until your chin tops the bar.

3. Push-up —With your hands shoulder-width apart, lower your chest, bending elbows to 90 degrees (keep body straight from shoulders to knees). Push back up.

4. Hanging abs —You'll need the hanging ab set-up at the gym for this one; stabilize arms and lift knees toward chest. Or substitute a crunch: lie face up with knees bent, sit up to 45 degrees, then lower.

5. Push-press —Hold dumbbells just above shoulder level. Bend knees to 90 degrees. Push arms overhead as you stand up, then lower weights back to shoulder level.

6. Biceps curl —Hold dumbbells down in front of you, palms facing out. Curl up till hands are near your shoulders, then lower.

7. Upright row —Standing, hold a bar with your arms straight down in front of you, palms facing your thighs and hands six inches apart. Pull the bar to chin level, then lower.

8. Triceps dip —Stand in front of a bench, reach back and grip the edge of the bench so that your forearms are facing away from you, keep your feet shoulder-width apart, firmly planted in front of you. Bend your knees and lower your butt until your upper arms are parallel to the floor, then push up.

9. Obliques curl —Lie on your side with your feet braced. Cross arms in front of chest and lift torso off the ground 20 degrees for 8-10 reps. Switch sides.