Why do you hold a stretch for 30 seconds? Good Question!
First, what is stretching for?
Stretching is meant to improve muscle elasticity which in turn improves flexibility and joint range of motion. Stretching helps elongate muscle fibers to make them stronger as well as realign disorganized collagen fibers in the direction of your pull. This reorganization of the collagen helps rehabilitate scarred tissue. When the fibers are nice and organized again, they pull better, work better, and make you feel better.
But why do we hold a stretch?
Let’s look at the basic physiological level:
Each muscle has a muscle spindle; stretching your muscle also stretches the muscle spindle. The muscle spindle sends this information to your spine to resist and protect your muscle in case you stretch too far. However, with a prolonged safe stretch, the muscle spindle habituates (or becomes accustomed to the stretch) and reduces signaling. Another factor to consider is the Golgi Tendon Organ (GTO). When the GTO is activated it inhibits the muscle spindle, relaxing you even further to achieve a greater stretch. So when you HOLD the stretch, the muscle spindle habituates and the GTO activates, allowing you to reach greater lengthening of the muscles fibers.
Since we know WHY we hold a stretch, how did we pick 30 seconds?
The research is not clear-cut, but many think that 30 seconds is the perfect amount of time to reach the ultimate benefits of flexibility.
One study showed that if you hold it any longer, there is no significant difference from the original benefits achieved at 30 seconds, so you may just be wasting your time. A systematic review explained that if you hold it longer than 45 seconds, it could negatively impact performance measures such as strength, speed, or power by potentially decreasing your ability to store energy.
However, (to confuse you even further) there is a study that said holding for over 180 seconds of stretching is required to decrease stiffness and improve flexibility.
Age impacts stretching time as well: Some say kids can stretch as little as they’d like to get the same effects, whereas adults over 65 should hold a stretch for longer because of age-related physiologic changes.
Just like a lot of things in science, there isn’t always a direct answer. As of now 30 seconds seems to be the accepted standard. It’s important to note that you don’t want to be too flexible; this can cause instability. Each muscle has an optimal length so it can stay strong and support your joints.
Basically, don’t hold the stretch for too long or too short: simple, right? Ask your Wallace and Nilan Physical Therapist to see what he or she thinks on the current research.
Thanks for tuning in on The More You Know – Check us out next week for more!