Going about our daily business, we naturally move our bodies in three dimensions or planes. Yet when exercising, we often move in only one plane at a time—so we miss the chance to gain the kind of muscle strength that could make everyday tasks easier and less likely to lead to injury.
When we spoke about this to exercise physiologist Irv Rubenstein, PhD, he explained that the body can be divided into three primary anatomical planes. The sagittal plane, which separates the right and left sides, is where forward-and-backward movement takes place. The frontal plane, which separates front from back, is where side-to-side movement takes place. The transverse plane, which divides top from bottom, is where rotational (twisting) movement takes place.
If this is confusing, picture your body divided (painlessly!) by a large pane of glass. When the pane separates your right side from your left, you can move forward or backward by sliding your two halves across the pane—but you can’t lean side-to-side or twist because the pane blocks those movements. When the pane divides your front from your back, you can slide to the right or left, but not twist or lean forward or backward. When the pane goes through your waist, separating your top from your bottom, you can twist your torso but not move to the side, front or back.
Why this matters: Many exercises work in only one plane. Sit-ups, for example, work in just the sagittal plane. Most everyday movements, however, work in two or three planes. Think of lifting a bag of groceries from a cart (sagittal plane), stepping sideways (frontal plane) and turning your torso to place the bag in your car trunk (transverse plane).
Dr. Rubenstein said, “When you exercise in one plane, you work a muscle or muscle group. But when you train across multiple planes, you train a movement. These movements mimic actions that you use to perform daily tasks—making you stronger overall and less prone to injury.”
To work in two or three planes at a time, Dr. Rubenstein recommended doing the routine below several times weekly. You don’t need a gym—just use household items as “weights” for resistance. If the weights suggested below are too challenging, use lighter ones or none at all. To warm up, walk in place for five minutes.
Repetitions: For each exercise, do 10 repetitions on the first side, then switch to the opposite side…complete two sets of 10 per side. Important: Check with your doctor before beginning any new exercise regimen. Exercises to try…
WOOD CHOP. Start: Stand with feet slightly wider than shoulder-width apart. With both hands, hold a five-pound sack of flour over left shoulder, elbows slightly bent. Move: Squat by bending knees as far as you comfortably can (not more than 90°). Hinge forward at hips approximately 30°, bringing sack down and across body to outside of right knee. Rise up out of squat and bring sack up to return to starting position.
STAND AND PRESS. Start: Stand at the bottom of a stairway, facing steps. Place left foot on lowest stair. With both hands, hold a five-pound sack of flour at chest height, elbows bent. Move: Transfer your weight to left foot and lift right foot off floor (as if climbing stairs) while straightening arms to raise sack overhead and rotating torso toward right side approximately 30°. Hold position for one to two seconds…return to starting position. Repeat, this time turning torso toward left side…return to starting position.
SIDE STEPPING. Start: Stand with feet hip-width apart. With both hands, hold a five-pound sack of flour over right shoulder, elbows slightly bent. Move: Keeping right leg straight, step left foot out to the side 18 to 24 inches, landing with toes pointed slightly out and knee bent. Hinge forward at hips, keeping back straight, and sweep sack down across body toward left knee, shin or foot (depending on your flexibility). Then push off with left foot and sweep sack up toward right shoulder, returning to starting position.
ONE-LEGGED ARM CURLS. Start: In right hand, grasp handles of a shopping bag that holds a half-gallon or one-gallon water jug. Stand on left foot with knee slightly bent…bend right knee to lift foot several inches off floor…arms are down at sides. Bend forward at hips about 30°. Move: Raise torso to stand erect as you bend right elbow, bringing bag up across torso until right hand is in front of left shoulder. Slowly lower arm and bend forward at hips, returning to starting position. To improve balance, try to stand on just one leg through all 10 reps.
BACK AND AROUND. Start: Lie facedown on a mat, legs straight. Hold a 16-ounce water bottle in right hand, elbow slightly bent and right arm resting on mat near your head. Move: Use back muscles to raise upper body off floor…rotate to right, bringing right arm back as if preparing to swing a racquet overhead. Hold for one to two seconds…slowly lower to starting position.
CRUNCH WITH TWIST. Start: Lie on your back, knees bent, feet flat on floor. Hold a 16-ounce water bottle in each hand, with arms slightly bent and resting on floor above head. Move: Contracting abdominal muscles, bring shoulders and upper back off floor…rotate to right at waist while sweeping arms forward past head, bringing hands toward right knee. Hold for one to two seconds…return to starting position.
