Exercise and Bone Density by Michelle Amore
There is evidence that exercise not only stimulates bone growth in adults and the elderly, but also reduces the loss of bone mass associated with aging. The type of stimulus used during exercise can directly effect bone mass, positively or negatively. While several methods of training can be used to increase bone mineral density (BMD), there are specific types of exercises, if executed regularly, that can have a positive effect on BMD.
Osteoporosis is a disease of the bone that makes a person’s bones brittle, weak and more likely to break. According to the National Osteoporosis Foundation, approximately 10 million Americans have osteoporosis and another 44 million have low bone density, placing them at increased risk. While hormonal changes and vitamin deficiencies aid in the cause of low BMD, a sedentary lifestyle and lack of weight bearing exercise also causes fragility and low T-scores. T- scores are used to help identify whether you have normal bone mass, low bone mass (osteopenia), or osteoporosis. When a T-score is -2.5 or below, you are diagnosed with osteoporosis. The lower your T-score, the greater your risk for fracture. Osteoporosis can also be diagnosed if you have had a fracture without trauma when you were older than 50. Speak to your healthcare provider to decide when you should take a Bone Mineral Density Test.
Whether attempting to increase BMD or prevent osteoporosis, weight-bearing aerobic activity and strength and resistance exercises should be a regular part of your weekly workout regimen. With an exorbitant amount of exercise options to choose from, it is important to prioritize activities that nudge bone forming cells, or osteoblasts, into action.
Weight-Bearing Aerobic Activities
Weight-bearing aerobic activities, or impact activities in which arms, feet, and legs are bearing the weight, that lead to improved bone mass include the following:
Stair Climbing
Jogging
Tennis
Dancing
Hiking
Hill Climbing
Walking, while advised for health maintenance, does not increase the loss of BMD as an isolated activity. Walking/jogging must reach a level of intensity that creates high enough forces to stimulate bone mass.
Strength and Resistance Training Exercises
Strength and resistance exercises are vital to the stimulation of osteoblasts and in limiting the reduction of BMD. Benedetti and colleagues recommend high loads (70-90% of a maximum repetition) for 8-10 repetitions of 2-3 sets performed at least for 1 year, 3 times a week for 45-70 minutes per session. Particular focus should be placed on exercises that stimulate the hips and spine to limit femoral neck and lumbar spine degradation. A few exercises that can be beneficial to the development of bone mass, prioritizing the hips and spine, are the following:
Weighted Squats or Body Weight Squats
Hold a kettlebell, dumbbell in both hands at chest level and stand with your feet hip-width to shoulder-width apart. Stand tall and brace your core, then drop your butt back and down as you keep your chest up, sitting back onto your heels without shifting your weight forward onto the balls of your feet.
Video - Weighted Squat with Dumbbells at Shoulder
Video - Weighted Squat with Dumbbells at Sides
Body weight squats can be performed the same way but without holding extra weight. Using a chair and proceeding to sit all the way down and stand all the way up is a great modification to a weighted squat.
Video - Chair Sit-to-Stand/Chair Squat
Leg Press
Lower the weight under control until the legs are roughly 45 degrees or slightly below. Drive the weight back to the starting position by extending the knees but don't forcefully lockout. Repeat for the desired number of repetitions.
Video - Prime Fitness Leg Press
Step-ups
Stand up facing an elevated platform with your arms at your side.
Put your right foot on an elevated platform. Step on the platform and use your heel to lift the rest of your body up. Place the foot of your left left on the platform.
Step down with your left leg controlling the movement as you descend. Return to a standing position by placing both feet next to each other on the ground.
Repeat this movement with the right leg for the desired number of times and then switch to your left leg.
Latissimus Pull Down
Place your knees under the provided pads. Position the pads so that your thighs are not able to raise up off the bench.
Grasp the lat bar with a little wider than shoulder-width grip. This is the starting position. Note: Hand position and the plane of motion should be adjusted based on an individual's joint mechanics.
Begin exercise by pulling your elbows out to the side and down while the bar travels down to your upper chest. Focus on using your lats to pull the bar down and not your arms.
Slowly reverse movement back to starting position.
Video - Parallel Plane Lat Pulldown
Dumbbell Bent Over Row
Take a dumbbell in each hand.
Slightly bend your knees and bend over at the waist so that your chest is almost parallel with the floor. Note: Spinal stabilization is required during this exercise to support the lumbar spine. This can be achieved through core engagement or lying your chest against a support.
Let the dumbbells hang in your arms and then pull them toward your mid-torso.
Lower the dumbbells back down to starting position.
Video - Bent Over Dumbbell Row
MODIFICATIONS
Video - Bench Supported Dumbbell Row
Video - Single Arm Supported Dumbbell Row
Additional exercise examples include hip extension, hip adduction, knee extension, hamstring curls, deadlifts, power cleans, military press, seated rows, back extension exercises, bench press, elbow flexion, wrist curl, reverse wrist curl, triceps extension, forearm pronation and supination, and so many more that can all be performed at prescribed levels of intensity to build bone.
All exercise descriptions are listed with the assumption that repetitions will be performed. Isometrically performing the exercising at 70-90% of maximum effort can be used rather than concentric and eccentric movements. Isometric exercise consists of pushing or pulling at a given effort level with the absence of joint motion. It is important to consult an exercise professional for individualized exercise prescription and guidance through a BMD program.