With the runner's never-ending search for a competitive edge, now and then something comes along that may actually "work" for the runner. One such piece of fitness equipment that can help runners is the BOSU Balance Trainer. It also provides a fun element as an addition to your training program and makes a nice change from running those miles on the road.

Here is what a BOSU Balance Trainer is and how it can help you. It is a blue rubber dome-shaped platform like the hemispherical upper third of a Swiss ball. It has a flat black rubber base 25 inches in diameter.

The name BOSU is an acronym for "both sides up," meaning the platform can be used lying flat on its base in a stable position, or turned upside down, and used as an unstable platform for more demanding exercises. When lying on its base it is more stable and lower to the ground than the Swiss ball and is thus easier to use by beginners, as it does not require as much balance and skill as its round Swiss ball counterpart. The BOSU originated in the U.S.A., quickly spreading to sports teams, then into the fitness club scene. Athletes of all abilities and sports use it.

How can using this piece of apparatus help your running? First, it should be used as an adjunct to your running training, and is not intended to replace your time spent on the roads--it will not do anything for your aerobic fitness.

Its main benefit is strengthening your core musculature, enabling your running posture to stay upright throughout your entire training or racing performance. This prevents your posture from slumping. When we slump forward, we tend to shorten our stride with an inevitable slowdown in time. So holding your posture upright when you tire is critical to maintaining your pace.

A secondary benefit of the BOSU is its ability to improve your balance, something that is essential to runners. Our balance is notoriously poor because we tend to just move in a forward plane, putting one foot in front of the other. The BOSU will help you stay better balanced and stabilized on rough, uneven surfaces like cross-country. You will better handle emergency movements like mounting a curb to a footpath, or changing direction rapidly such as in cross-country, leaping over small obstacles, etc.

Finally, the BOSU provides a much needed and fun diversion from grinding out those miles, especially if you are having particularly nasty weather and running outside in a blizzard is not feasible. You can set the BOSU up in your living room and work your core muscles without feeling guilty about missing a training run.

What is all the fuss about exercising the core? Here is a quick refresher for you on what the core muscles are. "The core" refers to the primary muscles of the abdominal region and low back, and also includes the other important muscles that stabilize and support your spine, including the spinal erectors, latissimus dorsi, gluteals, and trapezius.

The core is important because it is the hinge or epicenter for all movement that takes place in the human body. The core muscles may be the prime movers in an action, such as bending forward or backward, or the core may simply support and stabilize your trunk while other muscle groups are working, such as the shoulder muscles or arms.

If your core muscles are weak, you will experience early fatigue in the trunk, causing you to slump or lean forward while running. And you will slow down as a result because your steps will be shorter and your arms will not generate enough momentum to continue at race pace.

Here are ten challenging and fun BOSU exercises to strengthen your core. It will take several sessions to become comfortable and efficient with these exercises--but if you persist they will become much smoother. As you adapt to them, hold the position longer (if it is a static exercise), or perform more repetitions with light hand weights.

These exercises are best done in bare feet. I have added a more difficult variation of each exercise for when you are able to do these easily and need more of a challenge.

These are a variety of BOSU balance and strengthening exercises that you should be able to do after some practice. There are literally dozens of other exercises you can do as you master these--there are even BOSU classes that will show you a wider variety of exercises. Give them a try and you will feel the improved postural strength as you run and as you go about your daily activities.

1. Squat
Turn the BOSU upside down, with flat side on top. Step carefully onto the centre of the BOSU and get your balance, legs shoulder width apart. Slowly squat down until your thighs are parallel with the floor, then straighten your legs. You should feel your gluteals on your backside contracting if you are doing this properly.

Progression: add hand weights (dumbbells). Very advanced: squats with quarter or half turn, in small jumps.

2. Plank
Put BOSU flat side up and lower your forearms onto the base with your body straight. Make your hands into fists, thumbs up, and forearms forming a V with the point facing out. Hold your body straight for 30 seconds, three times.

Progression: hold for longer time.

3. Bridge
Put BOSU round side up and with your body facing upwards, lower your bent arms behind you to support yourself. Keep your body straight. Hold your body straight (keep backside up--not sagging). Do three repetitions of 30 seconds each.

Progression: hold for longer time. When that becomes easy reverse your position so your heels are on the BOSU (round side up) and your body flat parallel with the floor.

4. Bird Dog
Lie face down on BOSU (round side up) on your stomach or centre of gravity so you are evenly balanced. Slowly raise up your right arm and left leg, and then hold them for ten seconds in this "bird dog" position. The change arms and legs. Do three or four repetitions on each side.

Progression: do more repetitions, and more sets.

5. Balanced abdominal "bicycle".
Lie on your low back on BOSU, round side up, so you are evenly balanced. Hands beside your ears, elbows facing forwards. Slowly bring your left elbow and right knee together. Then cycle back and bring right elbow and left knee together. This will take some effort to balance properly until you get it right.

Progression: do more repetitions and more sets. Less advanced: V-sits where you sit on BOSU with hands behind your trunk for support, lifting your legs up in front of you.

6. Lunge
Place BOSU round side up. Face it and place your right foot on the centre of the BOSU. Slowly lower yourself down by bending your knee to a right angle. Slowly straighten your leg. Repeat ten times with each leg.

Progression: do more repetitions and more sets. Then hold dumbbells at your side, as you get stronger. These can be modified to faster moving lunges, bouncing yourself off the BOSU as soon as your foot hits it.

7. Push-Ups
Place BOSU flat side up, with round side on floor. Grip sides of BOSU tightly with hands--you'll see hand grip on the sides of the base for this. Slowly lower yourself by bending your arms, and then raise yourself by straightening your arms, doing the traditional push up exercise. If your upper body is not strong enough to do this, start with bent knees.

Progression: increase number of repetitions and sets.

8. Reverse Abdominal Crunch
Kneel in front of the BOSU, base up, round side down on floor. Place your forearms in a V position on the base, with fists together. Straighten your legs and trunk, and then raise your backside upwards to a right angle. Slowly lower your backside back down until your trunk is straight again. Repeat ten times, (if you can).

Progression: increase number of repetitions and sets.

9. Side Crunch
Place BOSU round side up. Lie sideways across BOSU with your ribs resting across the round centre part of the BOSU. Upper arm should be back behind your head. Lower arm should rest across your chest. Contract your side abdominals so you tilt upwards, and hold for 3 seconds. Lower, and then repeat. Repeat ten times (if you can).

Progression: increase number of repetitions and sets. Advanced: hold your body straight while lying on your side for ten seconds.

10. One Leg Balance
Place BOSU round side up. Stand with one leg on center of BOSU, slightly bent at knee. Lean forward with arms extended out in front of you, and other leg straight out behind you for balance. Hold for ten seconds. Repeat 10 times.

Another variation of this is to hold one leg out to your side, balancing with your arms.

Progression: hold for 20-30 seconds. Do up to 15 repetitions.

Roy Stevenson has a master's degree in coaching and exercise physiology from Ohio University. He has had more than 100 articles on running, fitness, and health published in various regional, national, and international magazines and newspapers. Formerly from New Zealand, Roy competed in NZ Championships on track, road, and cross-country. He held the NZ under-20 marathon record in 1974 when he ran his first marathon in 2:42:28.