Building strong bones to prevent osteoporosis and injury from falling is a goal for many of our members at Pratt’s Pro Fitness. I’m going to show you how to best go about building strong bones through exercise.
For years, some fitness influencers created a fear that lifting anything heavier than 3lb dumbbells would make you big and bulky.
This was incorrect and benefited no one.
Unless you’re jumping with the weight or throwing it, 3 lbs provides no challenge to your bones and muscles.
Now, the pendulum has swung the other way. Fitness influencers are claiming that you need to “Lift heavy s#!t.”
We’re not focusing on lifting heavy necessarily, but looking to exert a stress (force) on the bones. We can do that with high-impact activities like jumping and through low-impact activities like strength exercises … even bodyweight strength exercises like push-ups.
What does the research say?
A 2021 study by Kistler-Fischbacher and colleagues reviewed the research on developing bone density in post-menopausal women. They discovered that different regions of your body responded best to different intensities.
Note: 1RM stands for 1-repetition maximum. It’s the heaviest weight that you can lift for one repetition. On average, you can lift 80% of your 1RM for 8 repetitions, making that your 8RM.
They defined high, moderate, and low intensity as the following …
High force: Resistances greater than 80% of 1RM done for fewer than 8 reps and jump forces exceeding 4x bodyweight
Moderate force: Resistances of 65-80% of 1 RM done for 8-15 reps and jump forces at 2-4x bodyweight
Low force: Resistances less than 65% of 1RM done for more than 15 reps and jump forces less than 2x bodyweight
Looking at the above description, you might wonder how you’re going to match those jump forces if you can’t lift 4x your bodyweight.
Imagine you’re trying to bicep curl a 20lb dumbbell. Maybe it’s not that difficult to do. Now, try lifting it with a straight arm. It’s much harder because the lever is longer.
Your muscles have terrible leverage. It would be much easier to curl a dumbbell if your bicep were connected from your shoulder to your wrist. However, you would be so bulky if your muscles were well-leveraged. Instead, your bicep is connected close to your elbow. To curl that 20lb dumbbell, your bicep has to tug on your forearm with 100lbs of force … and the force is applied for longer than a high-impact jump.
It’s not the amount of weight used, but how hard your muscles work.
You can use weights, cables, resistance bands, or your own bodyweight. Your muscles and bones don’t know the difference.
What did the Kistler-Fischbacher study find?
High-intensity exercise wasn’t the best for all areas of the skeletal system.
The lumber spine responded best to high-intensity exercise.
The femoral neck (upper thigh) responded best to moderate and low-intensity exercise.
The hip responded best to moderate-intensity exercise.
How do we apply this information to our 40+ year old members at Pratt’s Pro Fitness?
High-Intensity
We like to perform 5-8 reps on our main strength exercises. These weights are more forgiving than the ones that you can only lift for 1-3 reps.
Main strength exercises include variations of the deadlift, squat, lunge, and press.
For jumps, we’re careful about what exercises we give to our members because the impact forces are so high. We prefer to focus on the muscular power benefits of jumps and leave the skeletal benefits to strength exercises.
Low to Moderate-Intensity
Accessory exercises like rows, push-ups, step-ups, and isolation exercises are done for 8-25 reps.
A Word on Running
Until recently, I would have told you that running was great for building strong bones. However, runners' bones are no stronger than those of the average person. After the first few minutes of running, the signal to build your bones shuts off. The repeated stress from thousands of steps makes it a draw. Training with varied movement, like in a team sport, is better for building strong bones.
In conclusion, building strong bones is best done through a variety of movements and intensities in the gym and is not limited to high-impact jumping and lifting heavy weights.
Source:
Kistler-Fischbacher, M. et al., The effect of exercise intensity on bone in postmenopausal women (part 2): A meta-analysis. Bone, 2021.
