Differences in kinetic asymmetry between injured and noninjured novice runners: A prospective cohort study
Introduction
Annually, 19–83% of all runners sustain a running-related injury (RRI) [1], [2]. Notwithstanding the high risk of sustaining an RRI, running is still one of the most popular physical activities. Injuries most common sustained among runners are medial tibial stress syndrome, patellofemoral pain syndrome, iliotibial band syndrome, stress fractures of the tibia, fibula or metatarsals, plantar fasciitis and Achilles tendinopathy [3]. Risk factors that put runners at higher risk for developing an RRI have been studied extensively [4], [5], [6]. Risk factors for RRIs can be divided into: training, anatomical and biomechanical factors [7]. Because of the high forces applied to the body with each foot strike, kinetic variables like impact peak [7], active peak, and loading rate, were often studied in relation to RRIs [7], [8], [9], [10], [11], [12]. Results from these often small and retrospective studies were contradictory. In a recent prospective study among 210 novice runners, no differences in kinetic peak values were found between runners who developed an RRI and runners who did not [13]. Therefore, magnitude of the impact and active peak forces might not be directly related to the development of an RRI.
Kinetic asymmetries between the left and right leg will expose one of the lower limbs to more stress than the other [14], [15]. Therefore, the musculoskeletal tissue of the leg that is exposed to higher levels of stress might be more susceptible to an overuse injury and it could be possible that reduced symmetry may result in RRIs. Only two studies examined this possible relation between kinetic asymmetry and RRIs [14], [15]. Both studies did not find differences in asymmetry between injured and noninjured runners. However, due to the retrospective character of both studies these findings might as well be the result of the injury. It can be argued that asymmetry is reduced as result of the injury, to decrease loading on the injured side. A prospective study can elucidate the possible causative nature of kinetic asymmetry on RRIs.
Studying the possible relation of kinetic asymmetry to RRIs is of importance for several reasons. Firstly runners at risk could be easily identified by measuring kinetic variables of both legs. Secondly, preventive measures such as the use of insoles or shoe modifications could be developed and introduced to reduce asymmetry in kinetic variables causative in the development of RRIs [16]. And thirdly, running technique could be modified in a way to reduce imbalances in load to the lower extremity and thereby decrease the risk on an RRI [17].
The purpose of this prospective study was threefold. First, describe natural levels of asymmetry. Second, compare levels of asymmetry between novice runners who sustained an RRI and novice runners who did not sustain an RRI. Third, compare kinetic variables between the injured and noninjured lower limb within the novice runners who sustained an RRI. It was hypothesized that runners who had higher levels of asymmetry in impact peak, active peak and loading rate were more likely to sustain an RRI on the side where loading was highest.
Section snippets
Methods
Novice runners between the 18 and 65 years old who had not sustained an injury of the lower extremity in the last 3 months before inclusion were recruited from the GRONORUN 2 study population [13]. The GRONORUN 2 study was a randomized control trial which studied the effect of a preconditioning program on the incidence of RRIs. An RRI was defined as any self-reported musculoskeletal complaint of the lower extremity or back causing a restriction of running for at least 1 week. After baseline
Results
Two hundred ten novice runners enrolled in the study, 133 (63.3%) female and 77 (36.7%) male runners. Mean age was 37.2 ± 11.2 years, body mass index (BMI) was 23.9 ± 3.4 kg m−2. Age (35.9 ± 10.7 versus 39.6 ± 11.4 years) and BMI (23.5 ± 3.5 versus 24.7 ± 3.1) in female runners were significantly lower compared to male runners. Leg length of female runners (0.91 ± 0.09) was significantly shorter than the male runners (0.96 ± 0.05). The incidence of an RRI during the 9-week running program was 16.2%. Twenty-three
Discussion
To our knowledge this is the first published prospective study in novice female and male runners that examined differences in symmetry of kinetic and spatio-temporal variables between injured and noninjured novice runners.
Conclusion
The current study showed that natural levels of symmetry at baseline were different per variable and also inter-individual differences were large. Significant differences were observed in the symmetry angles of the impact peak and contact time by direct comparison, however these relationships did not remain significant once other factors were accounted for in the regression analysis. The hypotheses that injured novice runners had higher levels of asymmetry in impact peak, active peak and
Conflict of interest
The authors declare that they have no conflict of interest.
References (28)
- et al.
The relationship between lower-extremity stress fractures and the ground reaction force: a systematic review
Clinical Biomechanics
(2011) - et al.
Side-to-side differences in overuse running injury susceptibility: a retrospective study
Human Movement Science
(2008) - et al.
Kinetic asymmetry in female runners with and without retrospective tibial stress fractures
Journal of Biomechanics
(2006) - et al.
Gait retraining to reduce lower extremity loading in runners
Clinical Biomechanics
(2011) - et al.
The symmetry angle: a novel, robust method of quantifying asymmetry
Gait and Posture
(2008) - et al.
Reproducibility of electromyography and ground reaction force during various running techniques
Gait and Posture
(2004) - et al.
Gait asymmetry: composite scores for mechanical analyses of sprint running
Journal of Biomechanics
(2012) - et al.
Incidence and risk factors of running-related injuries during preparation for a four-mile recreational running event
British Journal of Sports Medicine
(2010) - et al.
Incidence and determinants of lower extremity running injuries in long distance runners: a systematic review
British Journal of Sports Medicine
(2007) - et al.
Evaluation of lower extremity overuse injury potential in runners
Medicine and Science in Sports and Exercise
(2000)
Training errors and running related injuries: a systematic review
International Journal of Sports Physical Therapy
Risk factors for overuse injuries in runners
Current Sports Medicine Reports
Predictors of running-related injuries in novice runners enrolled in a systematic training program: a prospective cohort study
American Journal of Sports Medicine
Impact and overuse injuries in runners
Medicine and Science in Sports and Exercise
Cited by (47)
Reduced gravity effects on gait coordinative structures
2023, Life Sciences in Space ResearchAre alterations in running biomechanics associated with running injuries? A systematic review with meta-analysis
2023, Brazilian Journal of Physical TherapyGait asymmetry and running-related injury in female collegiate cross-country runners
2023, Physical Therapy in SportCitation Excerpt :Therefore, if clinicians are going to examine asymmetry in runners then analysis at just one speed is necessary to quantify asymmetry. Limb asymmetry during running is hypothesized to increase risk of injury due to exposure of one limb to greater amounts of stress than the other (Bredeweg et al., 2013; Zifchock et al., 2006, 2008a). However, there were no significant differences in magnitude of asymmetry between injured and uninjured runners in any of the variables investigated.
Are impact accelerations during treadmill running representative of those produced overground?
2022, Gait and PostureCitation Excerpt :With over 85% of runners predominantly training overground [1] it can be argued that the majority of running related injuries (RRIs) are associated specifically with overground running. However, laboratory-based treadmill testing of RRI risk factors remains common [2,3], most likely because it facilitates biomechanical analysis (i.e. concurrent loading, kinematics), enables easier provision of feedback/biofeedback [4] and allows for control of environmental conditions and running speed. It is unclear however, if treadmill-based assessment of loading is representative of loading during overground running.
Bilateral differences in coordination variability among injured and uninjured runners: A prospective study
2022, Journal of Biomechanics