Is Heavy Lifting the Only Way to Build Bone Density? Let’s Talk Intensity & Effort
Bone health is a hot topic in conversations around aging well and staying active. If you’ve followed this space, you’ve probably heard a common refrain: “You HAVE to lift heavy to protect your bones.” This often refers to compound lifts like deadlifts and back squats performed at 85% of your one-rep max (1RM), which are sometimes framed as the only “real” path to preventing bone loss.
And while heavy lifting can be highly effective, it’s not the only approach.
Let’s break down what “intensity” really means in resistance training—and why effort might be the most important piece of the puzzle when it comes to building and maintaining strong bones.
What Is “Intensity” in Resistance Training?
In scientific terms, “intensity” refers to the percentage of your one-repetition max (1RM):
- High intensity: 85%+ of 1RM (e.g., heavy barbell work)
- Moderate intensity: ~50–75% of 1RM
- Low intensity: Under 50% of 1RM
A lot of attention has been given to the LIFTMOR trial, which found that participants improved bone density using heavy compound movements plus impact loading. But it’s important to note that this study compared heavy lifting to minimal movement—so of course the more active group saw greater benefits.
What the study didn’t prove is that only heavy lifting works. It didn’t compare heavy lifting to moderate-intensity, high-effort training—and that’s where the broader research gets interesting.
What the Research Really Says
Recent reviews and meta-analyses offer a more nuanced view. Moderate and even low-intensity training can improve bone density—if the effort is high.
A 2020 meta-analysis by Souza et al. found that training at lower intensities (even around 40% of 1RM) can be effective, so long as the work is taken close to muscle fatigue.
Similarly, a 2021 review by Kistler-Fischbacher et al., examining over 100 studies, found that low, moderate, and high-intensity resistance training all contributed to bone density improvements across various populations. In some cases—especially around the hip—moderate intensity had an edge over heavier loads.
Effort > Intensity
Across the board, the biggest takeaway is that effort is key. That means:
- You don’t need to lift the heaviest weights in the gym.
- But you do need to challenge your body enough to drive adaptation.
- This means training close to muscle fatigue—where only a few good-form reps are left in the tank.
A common research oversight is matching training volume but not effort. For example, 3 sets of 16 reps at 40% of 1RM isn’t the same as 3 sets of 8 at 80%—unless both are taken near failure.
What Are Your Options for Building Bone Density?
If heavy lifting isn’t your thing, there are many other accessible ways to train with high effort:
- Strength training with dumbbells or resistance bands
- Bodyweight exercises performed to near fatigue
- Combination sets (start heavier, finish lighter)
- Jump or impact movements (if joint-friendly)
- Weighted walking or stair climbing
- Functional movement classes focused on resistance and stability
The common thread? You need to challenge your muscles, whether through load, reps, or time under tension.
Final Takeaways
Lifting heavy is not the only option to build stronger bones. You do need to train with effort and progression, but there are a variety of ways to do this. Good guidelines to focus on include:
- Progressive overload – Your body needs increasing challenge over time
- Training close to fatigue – Choose movements and resistance levels that get you there
- Consistency – Aim for 2–3x per week
- Sustainability – The best routine is one you can enjoy and maintain
At Roper Physical Therapy, we’re here to help you find the right path to health and a more confident, capable body. Whether you’re just starting out or looking to safely level up your training, a physical therapist can guide you through personalized strategies for effective, safe, and sustainable movement.
Book a session with one of our physical therapists today and let’s get started on building strength that lasts.