The Runner's Guide to Treadmill Cushioning: A Biomechanical Deep Dive

For anyone who loves to run, the fear of joint pain is a constant shadow. We’re often told that treadmills offer a “softer” run than pavement, but what does that really mean? Is it just marketing, or is there real science at play? The answer lies in a field called biomechanics, and understanding it can empower you to choose a better machine and become a better runner.

The goal of a good cushioning system, like the ProShox technology found on a ProForm treadmill, isn’t simply to be “soft.” The true goal is far more sophisticated: to intelligently manage the rate of loading on your body.

The Science: It’s Not the Force, It’s the Speed of the Force

When you run, your body endures a ground reaction force of up to 2.5 times your body weight with every step. However, studies in sports science have shown that the peak force isn’t the primary culprit for stress injuries. The real danger is the impact loading rate—how quickly that peak force is reached.

• Hard Surfaces (Concrete): The force peaks almost instantaneously, sending a sharp, jarring shockwave through your skeletal system.
• Cushioned Surfaces: A good system deforms upon impact, increasing the amount of time it takes for the force to reach its peak. This “slowing down” of the impact is what gives your body’s natural shock absorbers—your muscles, tendons, and ligaments—time to engage and dissipate the force safely.

So, when you’re evaluating a treadmill, don’t just ask “Is it soft?” Ask, “Does it intelligently slow down the impact?”

A Tour of Cushioning Technologies

While brand names vary, most treadmill cushioning systems fall into a few key categories:

1. Elastomer Cushioning: This is the most common type. Elastomers are rubber-like polymers placed at various points between the running deck and the frame. They compress on impact to absorb energy. Higher-end models, like those with ProShox, use strategically placed elastomers of varying density (durometer) to create a landing zone that is softer and a push-off zone that is firmer.
2. Adjustable Cushioning: Some premium treadmills offer adjustable cushioning. This allows you to change the firmness of the deck to simulate different running surfaces or to match your personal preference. You can have a softer, more forgiving surface for a long recovery run, and a firmer, more responsive surface for speed work.
3. Floating Deck Design: In these systems, the entire deck is isolated from the frame, often resting on large shock absorbers. This allows for a greater degree of movement and can provide a very effective, albeit often more expensive, cushioning solution.

Your Own Personal Cushioning System: Your Running Form

Here’s the most empowering secret: the most important cushioning system you have is your own body. No matter how advanced the treadmill, poor running form will still lead to high impact forces. Here are two key ways to improve your personal shock absorption:

• Increase Your Cadence: Cadence is the number of steps you take per minute. Many recreational runners have a low cadence (around 150-160). Elite runners are often closer to 180. A higher cadence forces you to take shorter, lighter steps, reducing the “braking” effect and impact of each footfall. Try running in place for one minute and count your steps to get a baseline.
• Avoid Overstriding: Reaching your foot far out in front of you (overstriding) and landing hard on your heel is a major cause of high impact forces. Focus on landing with your foot more directly underneath your body’s center of mass. A higher cadence naturally helps to correct this.

Conclusion: The Hardware/Software Synergy

The perfect run is a partnership. It’s the synergy between a well-engineered machine and a well-practiced runner. A treadmill with a sophisticated cushioning system provides the ideal hardware, creating a safe and forgiving environment. But by also working on your personal “software”—your running form—you take ultimate control over your long-term joint health. Choose a machine that slows the impact, and practice a form that lessens it. That is the true path to a lifetime of healthy running.