The Myth of Lifting with Your Knees

Many individuals have been advised, or have advised others, to lift with their knees rather than their back. The notion that a rounded back is detrimental is often rooted in common but unsupported posture advice.

A systematic review published in 2020, titled "To Flex or Not to Flex? Is There a Relationship Between Lumbar Spine Flexion During Lifting and Low Back Pain?" revealed that there was no significant correlation between lumbar spine flexion during lifting and the occurrence of disabling low back pain. The review indicated no notable differences in peak lumbar flexion between individuals with and without low back pain (LBP). This suggests that the common recommendation to avoid lumbar flexion while lifting to mitigate back pain risks lacks evidence.

While this review included only five studies, the initial searches revealed around 4,500 results, highlighting the scarcity of focused research on lifting with a rounded back. It is crucial to recognize that the burden of proof lies with those who assert that lifting in this manner is hazardous; they must provide solid evidence to substantiate their claims.

Exploring Misapplied Research

When personal trainers, physiotherapists, and medical professionals cite research to justify the dangers of lifting with a rounded back, they often refer to studies involving cadavers. The methodology employed in these studies—subjecting spines to mechanical stress thousands of times—does not accurately reflect the adaptive nature of living human bodies.

Cadavers do not adapt to stress in the way that live individuals do. Our bones, ligaments, tendons, and muscles respond to repeated stress through remodeling and strengthening. While overuse injuries can occur if the load is excessive, this is not exclusive to back injuries.

For instance, if someone who has never run suddenly decides to run 20 miles, they may suffer from pain such as Achilles tendinitis, but this does not imply that running is inherently dangerous. The same principle applies to lifting weights; if the body is unprepared for a load, strain can occur, but this does not necessarily lead to degeneration or herniations.

The cadaver studies fail to account for the complex factors of living biomechanics, including muscle action, blood flow, and nervous system regulation. Compressing years of lifting into a few hours of study does not provide a valid comparison to real-life lifting conditions.

Potential Benefits of Rounded Back Lifting

Research indicates that the spine can exhibit greater stability when flexed. In fact, keeping the back overly straight may increase shear forces at the lumbar spine during lifting, countering traditional beliefs about safe lifting mechanics.

A study comparing different lifting positions found that adopting a flexed posture could enhance neuromuscular recruitment and overall efficiency, potentially allowing for increased lifting capabilities. Powerlifters and strongman competitors often utilize a flexed posture to reduce the mobility demands on their hips and knees, enhancing their lifting mechanics.

The data reveal that even when participants were instructed to maintain a straight back, they often exhibited a degree of flexion. For example, strongman athletes can flex their backs up to 45 degrees during competition lifts.

Understanding Injury Complexity

Injuries can occur with both rounded and straight back lifting. I have personally experienced injuries from both techniques. Factors such as awkwardly carrying objects and repetitive heavy lifting contribute to low back pain, but body position is only one aspect of injury risk.

Research on workplace ergonomics shows that merely educating individuals on proper mechanics does not effectively reduce pain. Factors like job satisfaction, exercise tolerance, and overall health play significant roles in pain and injury.

To minimize injury risk, gradually introducing your body to specific activities and ensuring proper recovery is crucial. Factors such as sleep quality, diet, and stress management also influence training intensity and potential for injury.

Strength sports, including bodybuilding, have some of the lowest injury rates among athletic activities. This is particularly true when compared to contact sports and running.

Does Form Really Matter?

While proper form can enhance performance, it is not always necessary for preventing injury. Studies suggest that fear-based beliefs around lifting techniques can negatively influence lifting behavior.

For example, participants in a study exhibited their lifting mechanics based on their beliefs about body position. This often stems from societal teachings about lifting with the legs rather than the back. The research does not support the notion that our backs are inherently weak; rather, our bodies are resilient and capable.

Gradual exposure to feared movements is an effective strategy for reducing pain and enhancing confidence in lifting.

By starting with light weights and progressively increasing load and range of motion, individuals can safely build strength and resilience while overcoming fears associated with rounded back lifting.

Developing Resilience through Exercise

To cultivate resilience, two key strategies are essential: effective programming and recovery, along with varied posture and load exposure. Here are some exercises to consider:

1. Zercher Deadlifts: Begin with zercher squats before transitioning to deadlifts to enhance hip and lumbar mobility.
2. Rotating Deadlifts: Incorporate a twisting motion to assess hip mobility.
3. Strongman Lifts: Explore lifts like the Jefferson lift, suitcase lift, and barbell hack lift for unique challenges.

Always start slowly and gradually increase intensity and volume over time. Engaging in diverse lifting techniques can add variety to your routine and help build resilience.

If someone asserts that certain lifting techniques are unsafe, remind them that such claims require substantial evidence. Maintaining an exercise regimen can be challenging; let’s not add unnecessary barriers to movement.

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