Stretch exercises increase tolerance to stretch in chronic musculoskeletal pain

¶ … Chronic musculoskeletal pain necessitates the maintenance of good extensibility in order for normal functioning to be enhanced. This enhancement results in improvements in strength, endurance, fitness, and psychological well-being (Law et al., 2009). Programs promoting the improvement of movement for people with chronic musculoskeletal pain usually include stretching components. Stretching helps to improve functioning through improved range of motion within joints, and therefore muscle extensibility (Law et al., 2009).

The study by Law et al. (2009) emphasized the importance of tolerance and extensibility for individuals with chronic musculoskeletal pain. The purpose of the study, which was clearly outlined in the report, was to explore whether stretch affects either or both of these factors. The researchers hypothesized that individuals with chronic musculoskeletal pain may respond to stretch differently than individuals who do not experience chronic pain. Further to this suggestion, the researchers suggest that individuals with chronic musculoskeletal pain may show sensitivity to movement that is more pronounced and heightened, which is most likely a result of hypervigilance and fear of physical activity and associated pain that may be expected (Law et al., 2009). The primary objective of the study was to assess the effectiveness of a 3-week stretch program for improvement of extensibility in the hamstring muscle and to also examine stretch tolerance in individuals that experience chronic musculoskeletal pain.

The participants in the study were thirty adults, who were recruited from a list of pain management patients. Inclusion criteria for the study included the presence of musculoskeletal pain for at least a three-month period, likelihood to partake in hamstring stretching as part of a pain management program, and also be over the age of 18 years old. There were experimental and control conditions for the study, but both were within each participant, as every participant was assigned the treatment condition for one of their legs and the control condition for the other leg. The stretch treatment was a component of a multidisciplinary pain management program that is based largely in cognitively behavioral principles. The program includes the stretch component, as well as exercise, education, pacing, relaxation, reduction of drugs, prevention of relapse, sleep management, and involvement of the individual's family. The timeframe for the program is 3 weeks.

The stretch treatment is the experimental condition in the study. The participants were instructed to stretch the experimental leg for one minute every day for the duration of the 3-week pain management program. For the control condition, the participants were instructed to refrain from doing any sort of stretching exercise for the hamstring muscles on the control leg during this timeframe devoted to the study. The stretching applied to the experimental leg was self-administered by the participants, and it involve the participants sitting on the floor and maintaining full extension of the experimental laeg while they reached forward with both hands over top of it. The participants' adherence to the study intervention was monitored carefully by the researchers.

The measures used to measure effectiveness of the intervention were stretch tolerance and muscle extensibility. These measures were established at baseline prior to the commencement of the intervention as well as after the three-week duration of the study. The instrument used for these measures was a device that assessed hip flexor torque and passive hip flexion. The equipment used is thoroughly described in the report. The reliability of the instrument was described as good, but the researchers did not mention the validity of the measurement device.

The results section of the study thoroughly described the demographic characteristics of the sample, the adherence of the sample to the study protocol, as well as the effects observed from the intervention. The researchers described how at the beginning of the experimental trial, there were no differences observed between the experimental legs and the control legs. Similarly, there was no observed difference between experimental and control legs in terms of tolerance to stretch-related discomfort. Regarding muscle extensibility, after the 3-week stretch intervention, there was no demonstrated increase in extensibility of the hamstring muscle for the experimental leg in comparison to the control leg. However, the intervention did result in significant improvement in stretch tolerance between the experimental and control legs, with participants demonstrating more tolerance for stretch in the experimental leg. Table 2 on page 1023 of the study outlined the variables, the conditions in the study, as well as the between-group mean differences using a 95% confidence interval.