Why You Need To Be Strong To Be Flexible

In reality, flexibility is not the goal. True movement freedom isn’t about just being flexible—it’s about being mobile. Mobility isn’t simply stretching further; it’s about having access to a full range of motion and, more importantly, having the strength to control it. The goal isn’t to passively lengthen muscles indefinitely but to build stability and strength within our available movement. So how do we develop the mobility we need, rather than just chasing flexibility? The answer lies in strength!

Flexibility Vs. Mobility

Flexibility

Like I mentioned, flexibility is strictly the lengthening of a muscle. The more you can lengthen a muscle, the more flexible you are. That being said, sometimes we trick ourselves into thinking we are flexible. Instead of lengthening a muscle, often we are orienting or creating a posture that opens more space at a joint to put slack into a muscle. This slack can then be taken up to achieve more motion. An example of this is when we reach overhead, we sometimes extend the low back, putting slack into the latissimus dorsi muscle and allowing us to use that slack to get into more shoulder flexion. The issue here is we are compromising elsewhere to get “more” motion from a joint. In reality, we are just changing the environment (biomechanics) to complete the task of shoulder flexion.

When it comes to yoga, we are often working to “improve” flexibility, or the lengthening ability of the muscles, with a good mixture of orientation and compensation to help us achieve the positions along the way. Further, the effects of this muscle lengthening tend to be transient, or shortly lived.

Mobility

When we work to improve mobility, we make sure to prevent compensation through the surrounding joints and instead use patterns of movement that encourage motor control and multi-joint range of motion. Further, emphasis is on muscle contraction through lengthening and holding positions. Essentially, mobility is your available range of motion that you have adequate CONTROL over.

As you can imagine, it is mobility that we want to improve to see translation to sport, exercise, and overall health and longevity.

How do we improve mobility?

The best way we can improve mobility is through eccentric contractions. Eccentric contractions are active contractions of the muscle, while allowing the muscle to lengthen. An easy way to think of it is to consider having 1000lbs on your back as you slowly squat down. You are fighting the weight and actively trying to contract against the knee flexion, but the weight is winning, lengthening the muscles around the knee that are responsible for flexion as you try to shorten them and extend the knee.

Without needing to put 1000lbs on your back, we can eccentrically load muscles and joints by simply strength training, making sure to work into full joint range of motion! Even better, add a tempo to the lifts. A good start would be 4 seconds down, 2 seconds hold, 4 seconds up. You can use this for a squat, split squat, deadlift, straight leg deadlift, bicep curl, pull up, bench press, and beyond to improve your mobility.

Conclusion

Mobility isn’t just about being flexible—it’s about having control over your available range of motion. The most effective way to achieve this is by loading the joints through the specific ranges we aim to enhance. This approach not only optimizes mobility but also builds the motor control and strength necessary to make that mobility functional. In the context of exercise, sport, and longevity, mobility is a foundational quality that gives us the freedom to move with strength and purpose.

-Dr. Nick DC, MS, TPI, CSCS

If you would like to learn more about your body, pain, and performance, send Dr. Nick an email at contact@integratedrpc.com or call at (585)478-4379, or schedule a FREE discovery visit at Contact.

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