Sit and Reach Test: how to measure hamstring and lower back flexibility

The Sit and Reach Test is probably the most well-known and widely used flexibility test in general physical assessment, from schools to gyms and physical therapy clinics. Its big advantage is that it's quick, standardized, and lets you compare results against reference tables by age and sex — something not all mobility tests offer.

Although it has limitations (it doesn't clearly isolate the hamstrings from the lower back), it remains an excellent general screening test and a good starting point for any flexibility assessment.

What does this test measure?

The Sit and Reach mainly measures the flexibility of the posterior chain: the hamstrings, and to a lesser extent the lower back muscles and calves. The result is the distance the person can reach with their hands toward (or beyond) their toes, starting from a seated position with legs extended.

It's not a purely "lower back" test or a purely "hamstring" test: it's a combined measure of the entire posterior chain of the lower body and trunk.

Equipment needed

• A Sit and Reach box (ideally with a graduated scale) or, failing that, a measuring tape fixed to the floor and a box/step to brace the feet against
• A flat surface

Step-by-step protocol

1. The person sits on the floor, barefoot, with legs fully extended and the soles of their feet flat against the Sit and Reach box
2. The feet must be together and the knees fully extended (not bent) throughout the test
3. With hands overlapped (one palm on top of the other) and arms extended, have them slowly flex the trunk forward, sliding their hands along the scale on the box
4. The person should reach as far as possible and hold the final position for 1-2 seconds, without bouncing or using momentum
5. Record the distance reached (in cm), using the fingertip position at the point of maximum sustained reach as the reference
6. Repeat 2-3 times and record the best result

Common mistakes

• Allowing the knees to bend during trunk flexion, which artificially increases the reach
• Using bouncing or momentum instead of a controlled, sustained movement
• Not warming up beforehand, which can underestimate the person's true flexibility
• Comparing results without accounting for relative arm and leg length (this significantly affects the absolute result)

How to interpret the result

Approximate reference values for young adults (box with zero point at the feet, i.e., 0 cm = reaching the tips of the toes):

Category	Men (cm)	Women (cm)
Excellent	> 27	> 30
Good	17-27	21-30
Average	6-16	11-20
Below average	0-5	1-10
Poor	< 0	< 1

These values are approximate and vary depending on the exact protocol and reference table used. What matters most in practice is individual tracking: comparing the same person against themselves over time, rather than fixating on the absolute classification.

Related tests

The Sit and Reach is a good starting point, but if the result is low, it's worth narrowing things down with more specific tests:

• Schober test — to find out whether the limitation really comes from the lumbar spine and not the hamstrings
• Hamstring flexibility test — to isolate this specific muscle chain
• Active straight leg raise test — another way of assessing hamstring flexibility from a supine position

Track and follow up

The Sit and Reach is an ideal test for periodic reviews because it's quick and highly reproducible. In Movalytics you can record the distance reached at each assessment, compare it against the reference table by age and sex, and visually track whether your flexibility work is paying off over the weeks.

Frequently asked questions

Do I need to warm up before doing the Sit and Reach? Yes, a gentle general warm-up beforehand is recommended, since cold muscles can underestimate true flexibility and increase the risk of discomfort. Why is there a difference between men and women in the tables? Women tend to have, on average, greater posterior chain flexibility and somewhat different body proportions (arms/legs/trunk), which is reflected in the reference values. Does a low result mean tight hamstrings? Not necessarily. It can also be due to limited lumbar mobility, lack of motor control during trunk flexion, or simply body proportions (long legs and short arms give a worse result even if actual flexibility is normal).