Neuromuscular Electrical Stimulation Primes Feedback Control During a Novel Single Leg Task

Petrie, Michael A.; Johnson, Kristin A.; McCue, Patrick M.; Shields, Richard K.

doi:10.1080/00222895.2020.1789052

Cited by 2 publications

(6 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After training, athletes improved control of sagittal knee motion during the squatting task by approximately 3° to 5°, which is consistent with the improvement demonstrated by a mixed-sex, nonathletic cohort. 42 The implications of greater sagittal knee control by only a few degrees remain to be shown. Knee flexion angles differ by <5° when performing distinctly different jumping tasks, 13 supporting the potential relevance of minor changes in sagittal knee position to athletic performance.…”

Section: Discussionmentioning

confidence: 99%

“… 20 Participants then performed an SLS task protocol that consisted of a pretest, a training session, and a posttest, each separated by a 5-minute seated rest. 42 Upon completion of SLS testing, maximum volitional involuntary contraction (MVIC) testing was performed in the following order: isometric knee flexion; isometric knee extension; eccentric knee extension; and isometric plantarflexion. Serum was collected by a venous blood draw after the MVIC assessments.…”

Section: Methodsmentioning

confidence: 99%

“…The SLS task assesses visuomotor performance during dynamic weightbearing movement. 29 , 35 , 36 , 42 , 53 During the task, participants stood atop a stool on a single limb (test limb) with the knee strapped to a knee pad at the end of a rack and pinion system. The contralateral leg remained suspended off the ground ( Figure 1B ).…”

Section: Methodsmentioning

confidence: 99%

“…Participants performed a pretest, training session, and posttest according to a previous protocol. 42 The pretest and posttest consisted of 9 distinct test conditions that varied by resistance (5%, 10%, and 15% bodyweight) and velocity of the target signal (0.2, 0.4, and 0.6 Hz) that corresponded to ~13.3, 26.6, and 40 deg/s knee joint flexion/extension velocity. The training session consisted of 5 sets of 3 test conditions (10% bodyweight at 0.2, 0.4, and 0.6 Hz).…”

Section: Methodsmentioning

confidence: 99%

“… 36 Other work with the same SLS task showed that people can learn to improve feedforward and feedback knee control by training. 42 …”

mentioning

confidence: 99%

See 4 more Smart Citations

Influence of the Menstrual Cycle and Training on the Performance of a Perturbed Single-Leg Squatting Task in Female Collegiate Athletes

Johnson,

Shields

2024

Orthopaedic Journal of Sports Medicine

Self Cite

View full text Add to dashboard Cite

Background: Anterior cruciate ligament (ACL) injuries often occur when an athlete experiences an unexpected disruption, or perturbation, during sports. ACL injury rates may also be influenced by the menstrual cycle. Purpose: To determine whether training adaptations to knee control and muscle activity during a perturbed single-leg squatting (SLS) task depend on menstrual cycle phase in female athletes. Study Design: Controlled laboratory study. Methods: A total of 21 healthy female collegiate athletes (current or former [<3 years]) who competed in 9 different sports performed an SLS task in which they attempted to match their knee position (user signal) to a target signal. The protocol consisted of a 9-condition pretest, 5 sets of 3 training trials, and a 9-condition posttest. One perturbation was delivered in each condition by altering the resistance of the device. Sagittal knee control (absolute error between the target signal and user signal) was assessed using a potentiometer. Muscle activity during perturbed squat cycles was normalized to maximal activation and to corresponding muscle activity during unperturbed squat cycles (%unperturbed) within the same test condition. Athletes performed the protocol during a distinct menstrual cycle phase (early follicular [EF], late follicular [LF], midluteal [ML]). Two-way mixed analysis of variance was used to determine the effects of the menstrual cycle and training on knee control and muscle activity during task performance. Venous blood was collected for hormonal analysis, and a series of health questionnaires and anthropometric measures were also assessed to determine differences among the menstrual cycle groups. Results: After training, athletes demonstrated better knee control during the perturbed squat cycles (lower absolute error, P < .001) and greater soleus feedback responses to the perturbation (%unperturbed, P = .035). Better knee control was demonstrated in the ML phase versus the EF phase during unperturbed and perturbed squat cycles ( P < .039 for both). Quadriceps activation was greater in the ML phase compared with the EF and LF phases, both immediately before and after the perturbation ( P < .001 for all). Conclusion: Athletes learned to improve knee control during the perturbed performance regardless of menstrual cycle phase. The best knee control and greatest quadriceps activation during the perturbed squatting task was found in the ML phase. Clinical Relevance: These findings may correspond to a lower incidence of ACL injury in the luteal phase and alterations in exercise performance across the menstrual cycle.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

“… 36 Other work with the same SLS task showed that people can learn to improve feedforward and feedback knee control by training. 42 …”

mentioning

confidence: 99%

See 3 more Smart Citations

Influence of the Menstrual Cycle and Training on the Performance of a Perturbed Single-Leg Squatting Task in Female Collegiate Athletes

Johnson,

Shields

2024

Orthopaedic Journal of Sports Medicine

Self Cite

View full text Add to dashboard Cite

show abstract

Biomarkers for rapid H-reflex operant conditioning among females

Johnson

Petrie

Shields

2023

Journal of Neurophysiology

View full text Add to dashboard Cite

Operant conditioning of a spinal monosynaptic pathway using the Hoffman Reflex (H-reflex) is well established in animal and human studies. There is a subset within the human population (~ 20% non-responders) who are unable to up train this pathway suggesting some distinct or unique identifying characteristics. Importantly, females, who have a 9 times higher rate of injury during human performance activities than men, have been under-studied in areas of CNS neuroplasticity. Our long-term goal is to understand if innate ability to rapidly up train the H-reflex is predictive of future performance based injury among females. In this study, we determined whether healthy, young females could rapidly increase the H-reflex within a single session of operant conditioning and determined if electro-physiological, humoral, cognitive, anthropometric, or anxiety biomarkers distinguish the responders from non-responders. Eighteen females (Mean Age: 24) participated in the study. Ten females met the criteria for up training the H-reflex (responders). The responders showed lower levels of estradiol (P < 0.05) and trends for higher working memory (P = 0.06), higher maximal H-max/M-max ratio (P = 0.07), and higher basal metabolic rate (P = 0.07). A multivariate stepwise regression model supported that extracellular to intracellular water ratio (ECW/ICW) and H-max/M-max ratio explained 60% of the variation in the operant conditioning. These findings support that electro-physiological, hormonal, cognitive, and anthropometric characteristics are distinct among females capable of rapidly upregulating the H-reflex.

show abstract

Neuromuscular Electrical Stimulation Primes Feedback Control During a Novel Single Leg Task

Cited by 2 publications

References 28 publications

Influence of the Menstrual Cycle and Training on the Performance of a Perturbed Single-Leg Squatting Task in Female Collegiate Athletes

Influence of the Menstrual Cycle and Training on the Performance of a Perturbed Single-Leg Squatting Task in Female Collegiate Athletes

Biomarkers for rapid H-reflex operant conditioning among females

Contact Info

Product

Resources

About