In 1996, Halbertsma, et. al., investigated the effects of a brief stretching routine on individuals with short hamstrings. The study aimed to determine whether a single 10-minute stretch session could alleviate muscle stiffness and improve flexibility in this specific group of participants. The findings of this study shed light on the potential benefits of incorporating stretching exercises into sports and fitness routines.

The experiment involved sixteen participants, consisting of students from the Department of Human Movement Sciences, who volunteered for the study. Only individuals without a history of neurological or orthopedic disorders were included. To select subjects with short hamstrings, specific criteria were employed: the inability to touch the floor while bending forward (finger-ground distance greater than 0 cm) and a limited range of motion in leg lifting (not exceeding 80 degrees). The participants were randomly divided into two groups: one group of ten subjects performed a 10-minute static stretching routine, while the remaining six subjects served as the control group and received no treatment.

The researchers utilized an instrumental straight-leg-raising setup to measure various parameters, including the force required to lift the leg, range of motion (ROM), pelvic-femoral angle, and electromyogram (EMG) readings of the hamstring muscles. These measurements provided insights into muscle stiffness, elongation, and muscle activity levels.

The results of the randomized control trial revealed that a 10-minute sport stretch had a positive impact on individuals with short hamstrings. Specifically, the participants experienced significant improvements in their muscle flexibility and range of motion (ROM). The passive muscle moment, which measures the force required to lift the leg, increased noticeably after the stretching session. Additionally, the hamstrings showed significant elongation, indicating increased extensibility.

However, it is important to note that the study did not find any significant changes in the passive muscle stiffness curve compared to the pre-stretching stiffness curve. This suggests that while the participants’ flexibility and range of motion improved, there was no significant alteration in the overall muscle stiffness.

In conclusion, the findings indicate that a single 10-minute static stretching session can effectively enhance muscle flexibility and ROM in individuals with short hamstrings. This information highlights the potential benefits of incorporating stretching exercises into sports and fitness routines, allowing individuals to improve their overall performance and reduce the risk of muscle-related injuries.

Reference: Halbertsma, J. P., van Bolhuis, A. I., & Göeken, L. N. (1996). Sport stretching: effect on passive muscle stiffness of short hamstrings. Archives of physical medicine and rehabilitation, 77(7), 688-692.