Before moving on to Part 2, make sure you take a look at Part 1 of this post. In Part 2 we address practical ways to achieve motor benefits after injury using mTrigger biofeedback.
Numerous studies over the last decade have supported the use of external focus of attention compared to internal focus of attention for superior results when it comes to motor learning in rehab. (1,5,8–10) By using an external focus of attention with motor learning tasks, you can increase the cortical activity (“brain power”) associated with cognitive, motor, somatosensory, and visual movements. This facilitates the transfer of the movement to the subcortical regions of the brain and allows for programming of more complex motor actions.(5)
An external focus of attention directs attention towards the outcome or effects of the movement.(1,11) Cues such as “land in the box” or “reach for the cones” are examples of an external focus of attention. This is where real time biofeedback, such as mTrigger, can be useful in helping to improve movement deficits while optimizing motor learning.(10) For example, visual feedback to reduce knee joint loading during an unexpected sidestep cutting maneuver demonstrated better retention in athletes compared to verbal feedback and no feedback.(9) Furthermore, external cueing with visual feedback during a squat, drop vertical jump, and countermovement jump helped to increase knee range of motion and ankle dorsiflexion on landing, indicating “softer” and safer landing mechanics.(7) The use of external cueing with visual biofeedback enhanced the overall quality of movement and improved the athlete’s ability to remember that movement pattern going forward.(7)
In addition, different types of feedback will provide variable effects. Visual feedback has the largest and broadest effect.(8) When balance is trained with an external focus of attention, motor learning patterns improve as well as balance performance.(8) Direct feedback, which is straightforward feedback seen or verbalized, can also enhance motor learning.(7) Visual and video feedback encourage motor learning through a problem-solving process, which makes it excellent for learning purposes.(7) Self-controlled feedback as well as self-initiated feedback can be very effective as a progression during learning.(7) mTrigger’s features provide constant feedback during an exercise (Train mode) or slightly less real-time feedback (graph and average MVC functions in Track mode or Neuromuscular Deficit Test) to support learning. This gives users an ability to control the feedback environment. Over time, athletes should require less feedback as a result of acquisition and skill retention.(7)
By using neuromuscular training, you can improve motor control and sensorimotor functional connectivity between regions of the brain that effect knee motor control.(7) A study by Benjaminse et al demonstrated that after 6 weeks of neuromuscular training with visual stimulus, there was an increase in cortical-thalamic and cerebellar-thalamic connectivity in the brain. Note, the thalamus is located between the cortical and subcortical motor areas in the brain and serves as a “relay hub” for control of movement.(7) The cerebellum contributes to the timing of motor activity. The thalamus will receive and transmit sensory information from the cortical regions of the brain to the body (including from the cortical thalamic region).(7)
Sports require complex sensory and motor integration at alarmingly fast rates. There simply is not enough time to plan out a slow meticulous movement or take extra time to calculate out the best route. Incorporating neuromuscular training increases activity of the sensory and motor planning networks, making them more efficient (demonstrated by a decrease in motor cortex activity) at achieving proper movement patterns and low risk biomechanics.(7) Neuromuscular training, when done well, requires a high degree of cross-modal system integration (ie: visual, sensory, proprioception) which strengthens the cortical-thalamic connection.(7) This high degree of cross-modal system integration is exactly what we see in the demand of sports.(7) Neuromuscular training for cross modal integration with the use of (augmented) feedback strengthens the cortical-thalamic and cerebellar-thalamic connections in the brain, leading to improved knee biomechanics.(7) Basically, the faster and more efficient your brain is at interpreting the information it receives, the better and more effective the movement it produces.
The success of biofeedback for motor control is dependent on its ability to encourage understood motor learning strategies. This helps to re-organize the motor cortex of the brain to encourage neuroplasticity of the correct movement.(7) Thus, neural progressions should be part of our rehabilitation protocols. Such progressions may include changes in feedback (type, time, and duration), changes in sensory motor feedback (visual, vestibular, somatosensory), and progression of exercise.
Here are just a few examples of ways to use mTrigger surface EMG biofeedback to achieve these outcomes:
1. Squat with and without immediate biofeedback – Monitor recruitment timing or activation across muscle groups
2. Single Leg Squat – Dual channel quad and glute setup
3. Prone Hip Extension with and without feedback – Ensure the right muscles are firing
4. Running Man with immediate muscular activation biofeedback – Encourage continuous muscle activation
After looking at the integral role the central nervous system and brain play in establishing motor patterns, neuromuscular control, and motor learning, it would be foolish to overlook training these systems in rehab. The connection between the somatosensory cortex and cerebellar regions of the brain is vital for helping athletes incorporate and plan the complex movement patterns necessary for getting back to sport. During rehabilitation, mTrigger biofeedback can assist in providing external focus of attention during rehab tasks to improve motor deficits and optimize motor learning. By using neuromuscular training, you can begin to improve the cerebellar-thalamic and cortical-thalamic connections that assist in optimizing movement mechanics and preventing injury.
Don’t forget to brush up on Part 1 of this post!
Want to learn more about biofeedback?
1. Gokeler A, Neuhaus D, Benjaminse · Anne, Grooms DR, Baumeister J. Principles of Motor Learning to Support Neuroplasticity After ACL Injury: Implications for Optimizing Performance and Reducing Risk of Second ACL Injury Key Points. Sport Med. 2019;49:853-865. doi:10.1007/s40279-019-01058-0
2. Granacher U, Puta C, Gabriel HHW, Behm DG, Arampatzis A. Editorial: Neuromuscular training and adaptations in youth athletes. Front Physiol. 2018;9(SEP):1264. doi:10.3389/FPHYS.2018.01264/BIBTEX
3. Letafatkar A, Rajabi R, Tekamejani EE, Minoonejad H. Effects of perturbation training on knee flexion angle and quadriceps to hamstring cocontraction of female athletes with quadriceps dominance deficit: Pre-post intervention study. Knee. 2015;22(3):230-236. doi:10.1016/j.knee.2015.02.001
4. Diekfuss JA, Grooms DR, Yuan W, et al. Does Brain Functional Connectivity Contribute to Musculoskeletal Injury? A Preliminary Prospective Analysis of a Neural Biomarker of ACL Injury Risk HHS Public Access. J Sci Med Sport. 2019;22(2):169-174. doi:10.1016/j.jsams.2018.07.004
5. Grooms D, Appelbaum G, Onate J. Neuroplasticity following anterior cruciate ligament injury: A framework for visual-motor training approaches in rehabilitation. J Orthop Sports Phys Ther. 2015;45(5):381-393. doi:10.2519/JOSPT.2015.5549
6. Miko SC, Simon JE, Monfort SM, Yom JP, Ulloa S, Grooms DR. Postural stability during visual-based cognitive and motor dual-tasks after ACLR. J Sci Med Sport. 2021;24(2):146-151. doi:10.1016/J.JSAMS.2020.07.008
7. Benjaminse A, Otten B, Gokeler A, Diercks RL, Koen ·, Lemmink APM. Motor learning strategies in basketball players and its implications for ACL injury prevention: a randomized controlled trial. Knee Surgery, Sport Traumatol Arthrosc. 2017;25:2365-2376. doi:10.1007/s00167-015-3727-0
8. Sherman DA, Lehmann T, Baumeister J, Gokeler A, Donovan L, Norte GE. External Focus of Attention Influences Cortical Activity Associated With Single Limb Balance Performance. Phys Ther. 2021;101(12). doi:10.1093/PTJ/PZAB223
9. Bonnette S, DiCesare CA, Kiefer AW, et al. A Technical Report on the Development of a Real-Time Visual Biofeedback System to Optimize Motor Learning and Movement Deficit Correction. J Sports Sci Med. 2020;19(1):84. /pmc/articles/PMC7039015/.
10. Gokeler A, Benjaminse A, Hewett TE, et al. Feedback Techniques to Target Functional Deficits Following Anterior Cruciate Ligament Reconstruction: Implications for Motor Control and Reduction of Second Injury Risk NIH Public Access. Sport Med. 2013;43(11):1065-1074. doi:10.1007/s40279-013-0095-0