Back Scratch Test
The back scratch test (also known as the shoulder stretch test or Apley scratch test) measures upper-body (shoulder) flexibility, the distance between the middle fingers when one hand reaches over the shoulder and the other behind the back. A positive score means the fingers overlap; a negative score means they do not meet. It is part of the Senior Fitness Test battery (Rikli & Jones 1999, n=7,183 US community-dwelling adults aged 60-94). Percentile curves (P5-P95) are from the Senior Fitness Test Manual, 2nd edition (2013), modelled from the same sample. Women consistently score higher than men at all ages due to greater shoulder flexibility. Watch video demonstration
How to Perform This Test
- Equipment
-
- 18-inch (45 cm) ruler
- Steps
-
- Stand upright.
- Dominant hand reaches over the same shoulder, palm facing the back, fingers pointing down the spine.
- Non-dominant hand reaches behind the lower back, palm facing outward, fingers pointing up.
- Slide the hands toward each other as close as possible.
- Scoring
Measure the distance between the tips of the middle fingers. Record as negative if fingers do not touch, positive if they overlap, to the nearest 0.5 inch. Perform two trials; record the best score.
- Notes
Test both sides; use the side that produces the best score. Record which side was tested.
Data source: Rikli & Jones (SFT) About this study
Back Scratch Test Norms by Age and Sex (inches)
| Age | Sex | Percentile | ||||
|---|---|---|---|---|---|---|
| 5th | 25th | 50th | 75th | 95th | ||
| 60-64 | Male | -11.3 | -6.6 | -3.4 | -0.2 | 4.5 |
| Female | -6.4 | -3 | -0.7 | 1.6 | 5 | |
| 65-69 | Male | -12.1 | -7.4 | -4.1 | -0.8 | 3.9 |
| Female | -7.3 | -3.7 | -1.2 | 1.3 | 4.9 | |
| 70-74 | Male | -12.5 | -7.8 | -4.5 | -1.2 | 3.5 |
| Female | -7.9 | -4.2 | -1.7 | 0.8 | 4.5 | |
| 75-79 | Male | -14 | -9 | -5.6 | -2.2 | 2.8 |
| Female | -8.8 | -4.8 | -2.1 | 0.6 | 4.5 | |
| 80-84 | Male | -14.6 | -9.3 | -5.7 | -2.1 | 3.2 |
| Female | -9.5 | -5.4 | -2.6 | 0.2 | 4.3 | |
| 85-89 | Male | -14.1 | -9.4 | -6.2 | -3 | 1.7 |
| Female | -11.3 | -6.9 | -3.9 | -0.9 | 3.5 | |
| 90-94 | Male | -15.1 | -10.4 | -7.2 | -4 | 0.7 |
| Female | -13 | -8 | -4.5 | -1 | 3.9 | |
What to expect by age group
Among adults aged 60 to 64, the middle 50% score -6.6 to -0.2 inches for men and -3.0 to +1.6 inches for women (positive means the fingers overlap). Most adults have negative scores, meaning the fingers do not meet, and scores become more negative with each 5-year bracket; women score roughly 3 to 5 inches better than men across all ages. Scores below -6.6 inches (men) or -3.0 inches (women) are typically below average for this age group; scores above -0.2 inches (men) or +1.6 inches (women) are above average.
| Age | Males | Females |
|---|---|---|
| 60-64 | -6.6 to -0.2 | -3 to 1.6 |
| 65-69 | -7.4 to -0.8 | -3.7 to 1.3 |
| 70-74 | -7.8 to -1.2 | -4.2 to 0.8 |
| 75-79 | -9 to -2.2 | -4.8 to 0.6 |
| 80-84 | -9.3 to -2.1 | -5.4 to 0.2 |
| 85-89 | -9.4 to -3 | -6.9 to -0.9 |
| 90-94 | -10.4 to -4 | -8 to -1 |
Detailed Breakdowns
Select an age group and sex below for detailed percentile charts, tables, and ratings.
Frequently Asked Questions
What does the back scratch test measure?
Upper-body (shoulder) flexibility, specifically the range of motion needed to reach behind the back. This movement is important for everyday tasks like dressing, reaching a seat belt, or washing one's back.
How is the test performed?
The full step-by-step protocol is detailed in the 'How to Perform This Test' section above.
What do negative scores mean?
A negative score means the fingers did not meet, for example, -3.0 inches means there was a 3-inch gap between the middle fingers. Negative scores are common and normal, especially in men and at older ages. A score of zero means the fingertips just touched.
Why do women score higher than men?
Women generally have greater shoulder flexibility than men due to differences in joint structure and connective tissue elasticity. This pattern holds across all age groups in the normative data.
Can muscle mass affect back scratch scores?
Yes. Large upper-body muscles, particularly the triceps, deltoids, and latissimus dorsi, can physically limit how far the hand reaches behind the back, resulting in a lower score that reflects muscle bulk rather than poor joint flexibility. People who do regular resistance training may score lower on this test than their actual shoulder joint mobility would suggest. The normative sample (community-dwelling older adults) would have had relatively low muscle mass on average.
Why does this metric only cover ages 60-94?
The Senior Fitness Test was designed for older adults. The normative data (Rikli & Jones, n=7,183) was collected from community-dwelling adults aged 60-94. No large-scale normative data exists for younger adults on this specific test.
Where do the percentile values come from?
The percentile curves come from the Senior Fitness Test Manual (Rikli & Jones 2013, 2nd ed., ISBN 978-1-4504-1118-9), which models P5 through P95 from the original sample of 7,183 community-dwelling US adults aged 60-94 (Rikli & Jones 1999, DOI). All five percentiles we display (P5, P25, P50, P75, P95) come directly from the source, no approximation is needed.
Related Metrics
Senior Fitness Test Battery
This metric is part of the Senior Fitness Test, a validated 7-test battery for adults aged 60-94.