Validity of the modified back-saver sit-and-reach test: a comparison with other protocols

Area of Science:

• Kinesiology
• Sports Medicine
• Biomechanical Analysis

Background:

• Traditional sit-and-reach tests (CSR, MSR, BS) show limited validity for low-back flexibility but moderate validity for hamstring flexibility.
• The V sit-and-reach (VSR) test is practical, but its validity remains unestablished.
• Existing protocols have limitations in accurately assessing key flexibility measures.

Purpose of the Study:

• To introduce a novel Modified Back-Saver (MBS) sit-and-reach test, integrating advantages of existing protocols.
• To compare the criterion-related validity and reliability of the MBS test against classical (CSR), VSR, and Back-Saver (BS) tests.
• To evaluate the perceived comfort of different sit-and-reach protocols.

Main Methods:

• 158 college students (96 female, 62 male) participated in the study.
• Participants performed the CSR, VSR, BS (left/right), and MBS (left/right) tests in a randomized order.
• Scores were correlated with criterion measures to assess validity and reliability.

Main Results:

• All sit-and-reach tests exhibited very high intraclass reliability (r = 0.89–0.98).
• The MBS test showed the highest significant correlations with low-back and hamstring measures in both men (r = 0.47–0.67) and women (r = 0.23–0.54).
• MBS demonstrated significantly higher validity for low-back and hamstring flexibility in men compared to BS and CSR tests. MBS was also rated as the most comfortable protocol.

Conclusions:

• The MBS test is a reliable and valid measure for hamstring and low-back flexibility.
• The MBS test offers improved practical utility and validity compared to previous protocols, especially for men.
• The MBS protocol is recommended for its enhanced comfort and assessment capabilities.