Male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility

Abstract

Background: Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females. Objective: To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners. Method: Forty subjects (30.0±6.4 years) participated and were placed in one of 4 groups: flexible males (n=10), inflexible males (n=10), flexible females (n=10), and inflexible females (n=10). All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility) ANOVA (α=0.05). Results: Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05) and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01). For hip flexion at initial contact, a significant interaction existed (p<0.05). Flexible females (36.7±7.4º) exhibited more hip flexion than inflexible females (27.9±4.6º, p<0.01) and flexible males (30.1±9.5º, p<0.05). No differences existed for knee angle at initial contact, peak knee angle, peak hip angle, or peak hip moment. Conclusion: Hamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners.

Wearable Sensors Detect Differences between the Sexes in Lower Limb Electromyographic Activity and Pelvis 3D Kinematics during Running

“…In recent years, an increasing number of studies have been published in relation to the biomechanics of running, including factors that could help prevent and treat injuries in runners [ 8 , 9 , 10 , 11 ]. Running is a popular recreational activity, but a lack of adequate training in correct running techniques may account for the reported increase in injuries among these athletes [ 12 ].…”

Instrument-assisted soft tissue mobilization and proprioceptive neuromuscular facilitation techniques improve hamstring flexibility better than static stretching alone: a randomized clinical trial

“…This muscle group resides in the posterior compartment of the thigh and consists of the semitendinosus, semimembranosus, and biceps femoris muscles [1]. Mobility can become inefficient and overuse syndromes can result when the biomechanics of shortened hamstrings result in imbalanced forces on the joints of the lower extremity [3][4][5][6][7]. During running, poor hamstring flexibility results in larger loads on the knee joint due to increased passive tensioning and compensatory activation of the knee extensors [4,6].…”

“…Mobility can become inefficient and overuse syndromes can result when the biomechanics of shortened hamstrings result in imbalanced forces on the joints of the lower extremity [3][4][5][6][7]. During running, poor hamstring flexibility results in larger loads on the knee joint due to increased passive tensioning and compensatory activation of the knee extensors [4,6]. Multiple studies have linked a deficit in hamstring length to an increase in risk for hamstring strain [2,[8][9][10].…”

Hip, knee, and ankle kinematics during activities of daily living: a cross-sectional study

“…The range of motion (ROM) of the lower limb joints may be restricted in musculoskeletal patients with joint disease or bone fracture and in individuals who have undergone surgery such as total joint arthroplasty. 1 , 2 , 3 Restricted ROM of the lower limb joints hinders the performance of activities of daily living (ADL) 4 such as walking, standing up, and climbing stairs. 5 , 6 , 7 Patients may also have difficulty with activities such as dressing, using the toilet, bathing, picking up objects, crouching, tying shoelaces, and clipping toenails.…”