ObjectivesThis study aimed to determine whether looped resistance bands affect knee kinematics and lower body muscle activation during the barbell back squat.MethodsTwenty-six healthy participants (13 female, 13 male) calculated their one repetition maximum (RM) prior to data collection. Each participant performed three squats at both 80% and 40% 1RM wearing a light resistance band, an extra-heavy resistance band and no resistance band.Vicon 3D motion analysis cameras were used to collect the kinematic data, and Delsys Trigno Lab wireless electromyography (EMG) system was used to measure vastus medialis, vastus lateralis, gluteus maximus, gluteus medius and biceps femoris muscle activity. Peak knee flexion angle, peak knee valgus angle and maximum tibial rotation values were examined. Peak EMG values were also analysed after being normalised and expressed as a percentage of maximum voluntary contraction (MVC).ResultsGluteus maximus (GM) activity is significantly increased when a resistance band is used during squatting. However, squatting with a resistance band is detrimental to knee kinematics as it leads to an increase in knee valgus angle and maximum tibial rotation angle. A direct correlation is recorded between an increase in resistance and an increase in these two angles.ConclusionsSquatting with resistance bands is likely to increase the risk of knee injury. Coaches and clinicians who already implement this technique are advised to remove resistance band squats from training and rehabilitation programmes. Further research evaluating the long-term effects of using resistance bands during the barbell back squat should be considered.

Background: The aim of this study was to determine whether toe sliding is more likely to cause knee injuries than flatfoot sliding in curling. Methods: Twelve curlers participated in the study, each delivering stones. Six stones per volunteer were delivered using a flatfoot slide and 6 were delivered using a toe slide. The Pedar-X inshoe pressure system recorded the plantar pressure present during each of the slides, while a sagittal plane digital video recorded the body position of the curler. Measurements were taken from the video recordings using a software overlay program (MB Ruler), and this combined with the Pedar-X data gave the overall joint force in the tuck knee. Results: Results showed a statistically significant difference between theThe knee joint force calculated for flatfoot sliding and toe sliding, with toe sliding being was more than double that of flatfoot sliding (p<0.05). A There was a strong correlation was found between the increase in knee joint force and the increase in the moment arm of the ground reaction force. Images produced using the 3D Vicon  system confirm that toe sliding produces a larger moment arm than flatfoot sliding. Conclusion: The knee is on average the most common joint affected in curlers. Injuries are more likely to occur in toe sliding, compared to flatfoot sliding, due to the increase din force and moment, pushing the weight of the curler forward over the knee, which could make causing the adopted position to be less stable. This study recommends that curlers Curlers should might consider avoiding toe sliding in order to reduce the risk of knee injuries if the two types of delivery could be performed equally well.

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BackgroundThe aim of this study was to determine whether toe sliding is more likely to cause knee injuries than flatfoot sliding in curling.MethodsTwelve curlers participated in the study, each delivering 12 stones. Six stones per volunteer were delivered using a flatfoot slide and six were delivered using a toe slide. The Pedar-X in-shoe pressure system recorded the plantar pressure during each of the slides, while a sagittal plane digital video recorded the body position of the curler. Measurements were taken from the video recordings using a software overlay program (MB Ruler), and this, combined with the Pedar-X data, gave the overall joint force in the tuck knee.ResultsThe knee joint force for toe sliding was more than double that of flatfoot sliding (p<0.05). There was a strong correlation between the increase in knee joint force and the increase in the moment arm of the ground reaction force. Images produced using the three-dimensional Vicon system confirm that toe sliding produces a larger moment arm than flatfoot sliding.ConclusionInjuries are more likely to occur in toe sliding, compared with flatfoot sliding, due to the increase in force and moment, pushing the weight of the curler forward over the knee, which could make the adopted position less stable. Curlers might consider avoiding toe sliding to reduce the risk of knee injuries if the two types of delivery could be performed equally well.