New research reveals how long, hard and often you need to stretch to improve your flexibility

Can you reach down and touch your toes without bending your knees? Can you stretch both arms upwards? If this sounds like a struggle, you may lack flexibility.

Flexibility is the ability to move a joint through its full range of motion. It supports you in most sporting activities and can prevent muscle injuries. And since most everyday activities require some degree of flexibility (e.g. bending or twisting), it helps you maintain functional independence as you age.

Although there are many types of stretching, static stretching is the most common. It involves positioning a joint to stretch the muscles and holding it still for a specific period of time, usually between 15 and 60 seconds. An example would be standing in front of a chair, placing one foot on the chair and straightening the knee to stretch the hamstrings.

Static stretching is often used to improve flexibility. However, there are no clear recommendations on the optimal amount required. Our new study looked at how long, how hard and how often you need to stretch to improve your flexibility – probably less than you expect.

Evaluation of the data

Our research team has spent the past year collecting data from hundreds of studies on thousands of adults around the world. We examined 189 studies involving more than 6,500 adults.

Studies compared the effects of a single session or multiple sessions of static stretching on one or more flexibility outcomes compared to those who did not do any stretching.

How long?

We’ve found that holding a stretch for about four minutes (total) in a single session is optimal for immediate improvement in flexibility. Any longer and you don’t seem to notice any further improvement.

To permanently improve flexibility, it seems you need to stretch a muscle for longer periods of time – about ten minutes a week to get the most improvement. However, this doesn’t have to happen all at once.

How heavy?

You can think of stretching as hard if you’re in pain, or easy if you don’t find the stretch uncomfortable.

The good news is how hard you stretch doesn’t seem to matter – both strong (stretching to the point of discomfort or pain) and light stretching (stretching to the point of discomfort) improve flexibility equally.

How often?

If you want to improve your flexibility, it doesn’t matter how many times you stretch each week. What’s important is that you aim for up to ten minutes per week for each muscle you stretch.

For example, you could stretch each muscle for a little over a minute a day, or five minutes twice a week.

How much time you should spend stretching ultimately depends on how many muscles you need to stretch. If you are less flexible, you will probably need to spend more time because you will have more “tight” muscles to stretch than someone who is more flexible.

Can everyone improve their flexibility?

Fortunately, it doesn’t matter what muscle you’re stretching, how old you are, what gender you are, or whether you’re a couch potato or an elite athlete – everyone can improve their flexibility.

Static stretching can be done anywhere, anytime. And you don’t need any equipment. You can stretch to relax while watching your favorite TV show, in the office, or after walking the dog. It’s a great way to start and end the day.

Although the exact stretches required depend on which muscles are “tight,” examples of some very common stretches include:

• Place one foot on the bench and bend forward at the waist while keeping your knee straight to stretch your thigh muscles
• Bend your knee and hold your ankle to your buttocks to stretch your quadriceps muscles
• Reach one arm and bend your elbow at the same time to stretch your triceps muscles.

The best advice, however, is to see a qualified doctor, such as a physical therapist or exercise physiologist, who can carry out an assessment and prescribe a list of stretching exercises specifically tailored to your individual needs.

As you can see, it really isn’t all that much effort to become more flexible.