Context: Decreased hamstring flexibility can lead to a plethora of musculoskeletal injuries, including low back pain, hamstring strains, and patellofemoral pain. Lack of flexibility may be the result of myofascial adhesions. The fascia connected to the hamstrings is part of the superficial back line that runs from the cranium to the plantar aspect of the foot. Any disruption along this chain may limit the flexibility of the hamstring. Objective: To investigate if self-myofascial release (SMR) of the plantar surface of the foot in addition to the hamstring group was more effective at improving the flexibility of the hamstrings when compared with either intervention alone. Design: Cross-over study. Setting: Athletic training facility. Participants: Fifteen college students (5 males and 10 females; age: 20.9 [1.4] y, height: 173.1 [10.3] cm, mass: 80.0 [24.9] kg) who were not older than 30, with no history of low back pain or injury within the past 6 months, no history of leg pain or injury within the past 6 months, no current signs or symptoms of cervical or lumbar radicular pain, no current complaint of numbness or tingling in the lower-extremity, and no history of surgery in the lower-extremity or legs. Interventions: Each participant received each intervention separated by at least 96 hours in a randomized order: hamstring foam rolling, lacrosse ball on the plantar surface of the foot, and a combination of both. Main Outcome Measures: The sit-and-reach test evaluated hamstring flexibility of each participant before and immediately after each intervention. Results: There were no significant differences found among the SMR techniques on sit-and-reach distance (F2,41 = 2.7, P = .08, ). However, at least 20% of participants in each intervention improved sit-and-reach distance by 2.5 cm. Conclusions: SMR may improve sit-and-reach distance, but one technique of SMR does not seem to be superior to another.
An exploratory study of different definitions and thresholds for lumbar disc degeneration assessed by MRI and their associations with low back pain using data from a cohort study of a general population