Back-Saver Sit-and-Reach

The modified back-saver sit-and-reach is the flexibility test in the FitnessGram battery. Unlike the standard box sit-and-reach, it is performed one leg at a time: the tested leg is fully extended against the box while the other knee is bent, foot flat on the floor. This removes the confounding effect of lower back tightness and reduces spinal flexion stress. The right leg is the primary FitnessGram reporting leg. Also known as the back-saver sit-and-reach or modified sit-and-reach. Data are from Santos et al. (2014), a nationally representative Portuguese sample of 22,048 children and adolescents aged 10-18 using the FitnessGram Test Battery v8.0. Percentile curves estimated using Cole's LMS method.

How to Perform This Test (Protocol)

Equipment

Sit-and-reach box or ruler fixed to a wall

Protocol Steps

Participant sits on the floor facing the box. One leg is fully extended with the foot flat against the box; the other knee is bent with the foot flat on the floor.
Both hands are placed on top of each other, palms down, on the measuring surface.
The participant slowly reaches forward along the measuring scale as far as possible, holding the position for at least 1 second.
The score is the distance reached (in cm). Perform twice and record the best of two trials.
Repeat the procedure with the other leg.

Scoring

Distance reached in centimetres, right leg. Higher scores indicate better hamstring and lower-back flexibility.

Notes

FitnessGram reports the right leg as the primary score. The Santos 2014 norms on this page are for the right leg.

Data source: Santos et al. 2014 (FitnessGram) (2014) · n=22K About this study

Back-Saver Sit-and-Reach Norms Chart by Age and Sex (cm)

Age	Sex	Percentile
		5th	25th	50th	75th	95th
10	Male	12.0	18.4	22.4	26.2	31.4
10	Female	13.0	19.2	23.4	27.6	33.5
11	Male	11.2	17.6	21.7	25.7	31.1
11	Female	13.0	19.1	23.3	27.6	33.9
12	Male	10.5	17.0	21.2	25.4	31.1
12	Female	13.3	19.3	23.7	28.2	34.9
13	Male	10.3	16.8	21.3	25.6	31.7
13	Female	13.9	20.0	24.5	29.3	36.4
14	Male	10.6	17.3	21.9	26.5	33.0
14	Female	14.6	20.8	25.5	30.4	37.6
15	Male	11.1	18.0	22.9	27.8	34.8
15	Female	15.3	21.6	26.2	31.1	38.3
16	Male	11.8	18.9	23.9	29.1	36.7
16	Female	15.9	22.2	26.8	31.5	38.5
17	Male	12.5	19.5	24.6	30.0	37.9
17	Female	16.6	23.0	27.5	32.0	38.7
18	Male	13.0	19.9	25.0	30.4	38.5
18	Female	17.3	23.7	28.1	32.5	38.9

What to expect by age group

At age 13, the middle 50% of boys score 16.8 to 25.6 cm and girls score 20.0 to 29.3 cm. Girls consistently score higher than boys, a pattern that holds across the full 10-18 age range. Both sexes show a gradual improvement with age. Scores below 16.8 cm (boys) or 20.0 cm (girls) are typically below average for 13-year-olds.

Typical range (25th to 75th percentile) by age group (cm)
Age	Males	Females
10	18.4 to 26.2	19.2 to 27.6
11	17.6 to 25.7	19.1 to 27.6
12	17.0 to 25.4	19.3 to 28.2
13	16.8 to 25.6	20.0 to 29.3
14	17.3 to 26.5	20.8 to 30.4
15	18.0 to 27.8	21.6 to 31.1
16	18.9 to 29.1	22.2 to 31.5
17	19.5 to 30.0	23.0 to 32.0
18	19.9 to 30.4	23.7 to 32.5

Detailed Breakdowns

Select an age group and sex below for detailed percentile charts, tables, and ratings.

Males

10 11 12 13 14 15 16 17 18

Females

10 11 12 13 14 15 16 17 18

Age trend (percentiles)

Frequently Asked Questions

How does this differ from the standard sit-and-reach?

The standard box sit-and-reach tests both legs simultaneously, which can confound hamstring tightness with lower back stiffness. The back-saver version tests one leg at a time with the other knee bent, isolating hamstring flexibility and reducing spinal flexion load. The two tests are not interchangeable; scores from different protocols should not be compared.

Why are only right-leg norms shown?

FitnessGram reports the right leg as the primary score. Santos et al. 2014 published separate percentiles for both legs; left-leg values are similar but not identical. This page uses right-leg data to match the FitnessGram reporting convention.