Context: This study aimed to examine the differences in electromyographic (EMG) activity of the biceps femoris long head (BFlh) and semitendinosus (ST) muscles, break-point angle (BPA), and the angle at peak BFlh EMG activity between bilateral and unilateral Nordic hamstring exercise (NHE) on a sloped platform. Design: This study was designed as a case-control study. Methods: Fourteen men participated in the study. The participants initially performed maximum voluntary isometric contraction (MVIC) on the prone leg curl to normalize the peak hamstring EMG amplitude as the %MVIC. Then, participants were randomized to perform the following 3 variations of NHE: bilateral (N40) or unilateral (N40U) NHE with a platform angle of 40°, and unilateral NHE with a platform angle of 50° (N50U). The EMG activities of the BFlh and ST and the knee flexion angle during the NHE variations were recorded to calculate the EMG activity of the BFlh and ST in terms of the %MVIC, the angle at peak BFlh EMG, and BPA. Results: The BFlh %MVIC was significantly higher in N40U (P < .05) and N50U (P < .05) than in N40. A significant difference in BFlh %MVIC and ST %MVIC was observed between N40U (P < .05) and N50U (P < .05). The mean values of BPA and the angle at peak BFlh EMG were <30° for all NHE variations. Conclusions: In the late swing phase of high-speed running, BFlh showed higher EMG activity; thus, unilateral NHE may be a specific hamstring exercise for hamstring injury prevention.
Toshiaki Soga, Taspol Keerasomboon, Kei Akiyama, and Norikazu Hirose
Daniel Viggiani and Jack P. Callaghan
Viscoelastic creep generated in the lumbar spine following sustained spine flexion may affect the relationship between tissue damage and perceived pain. Two processes supporting this altered relationship include altered neural feedback and inflammatory processes. Our purpose was to determine how low back mechanical pain sensitivity changes following seated lumbar spine flexion using pressure algometry in a repeated-measures, cross-sectional laboratory design. Thirty-eight participants underwent a 10-minute sustained seated maximal flexion exposure with a 40-minute standing recovery period. Pressure algometry assessed pressure pain thresholds and the perceived intensity and unpleasantness of fixed pressures. Accelerometers measured spine flexion angles, and electromyography measured muscular activity during flexion. The flexion exposure produced 4.4° (2.7°) of creep that persisted throughout the entire recovery period. The perception of low back stimulus unpleasantness was elevated immediately following the exposure, 20 minutes before a delayed increase in lumbar erector spinae muscle activity. Women reported the fixed pressures to be more intense than men. Sustained flexion had immediate consequences to the quality of mechanical stimulus perceived but did not alter pressure pain thresholds. Neural feedback and inflammation seemed unlikely mechanisms for this given the time and direction of pain sensitivity changes, leaving a postulated cortical influence.
Eugene Tee, Jack Melbourne, Larissa Sattler, and Wayne Hing
Context: Acute lateral ankle sprain (LAS) is a common injury in athletes and is often associated with decreased athletic performance and, if treated poorly, can result in chronic ankle issues, such as instability. Physical performance demands, such as cutting, hopping, and landing, involved with certain sport participation suggests that the rehabilitation needs of an athlete after LAS may differ from those of the general population. Objective: To review the literature to determine the most effective rehabilitation interventions reported for athletes returning to sport after acute LAS. Evidence Acquisition: Data Sources: Databases PubMed, Embase, CINAHL, SPORTDiscus, and PEDro were searched to July 2020. Study Selection: A scoping review protocol was developed and followed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Extension for Scoping Reviews guidelines and registered (https://osf.io/bgek3/). Study selection included published articles on rehabilitation for ankle sprain in an athletic population. Data Extraction: Parameters included athlete and sport type, age, sex, intervention investigated, outcome measures, measurement tool, and follow-up period. Data Synthesis: A qualitative synthesis for all articles was undertaken, and a quantitative subanalysis of randomized controlled trials and critical methodological appraisal was also conducted. Evidence Synthesis: A total of 37 articles were included in this review consisting of 5 systematic and 20 narrative reviews, 7 randomized controlled trials, a single-case series, case report, position statement, critically appraised topic, and descriptive study. Randomized controlled trial interventions included early dynamic training, electrotherapy, and hydrotherapy. Conclusions: Early dynamic training after acute LAS in athletes results in a shorter time to return to sport, increased functional performance, and decreased self-reported reinjury. The results of this scoping review support an early functional and dynamic rehabilitation approach when compared to passive interventions for athletes returning to sport after LAS. Despite existing research on rehabilitation of LAS in the general population, a lack of evidence exists related to athletes seeking to return to sport.
Stephanie Wise and Jordan Bettleyon
Clinical Scenario: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of the upper-extremity. Due to the involvement of the median nerve, long-term compression of this nerve can lead to hand dysfunction and disability that can impact work and daily life. As such, early treatment is warranted to prevent any long-term damage to the median nerve. Conservative management is utilized in those with mild to moderate CTS. Neural mobilizations can aid in the reduction of neural edema, neural mobility, and neural adhesion while improving nerve conduction. Clinical Question: Is neurodynamics effective in reducing pain and reported symptoms in those with CTS? Summary of Key Findings: Four studies were included, with 2 studies utilizing passive neural mobilizations, one study using active techniques, and one study using active neural mobilizations with splinting. All studies showed large effect size for pain, symptom severity, and physical function. Clinical Bottom Line: Neurodynamics is an effective treatment for CTS. Splinting is only effective when combined with neurodynamics. Strength of Recommendation: Level B evidence to support the use of neurodynamics for the treatment of CTS.
Masahiro Kuniki, Yoshitaka Iwamoto, Daiki Yamagiwa, and Nobuhiro Kito
Context: Core stability is important for preventing injury and improving performance. Although various tests for evaluating core stability have been reported to date, information on their relationship and the effect of gender differences is limited. This study aimed to (1) identify correlations among the 3 core stability tests and to examine the validity of each test and (2) identify gender differences in the test relationship and determine whether gender influenced test selection. Design: Cross-sectional study. Methods: Fifty-one healthy volunteers (27 men and 24 women) participated in the study. The participants underwent the following 3 tests: Sahrmann Core Stability Test (SCST), the lumbar spine motor control tests battery (MCBT), and Y Balance Test (YBT). Each parameter was analyzed according to all parameters and gender using the Spearman rank correlation coefficient. Results: Overall, there was a strong positive correlation between SCST and MCBT and moderate positive correlations between SCST and YBT and between MCBT and YBT. Conversely, gender-specific analyses revealed no significant correlations between YBT and SCST and between YBT and MCBT in women, although significantly strong correlations were found among all tests in men. Conclusion: Although these 3 tests evaluated interrelated functions and may be valid as core stability tests, the results should be carefully interpreted when performing YBT in women.
Mohammad Hamzeh Shalamzari, Hooman Minoonejad, and Foad Seidi
Context: Range of motion (ROM) and muscular strength are the main factors that affect athletic performance. Self-myofascial release is a flexibility technique, which is used to inhibit overactive muscle fibers. Objective: To investigate the effects of the 8-week self-myofascial release on the isokinetic hamstrings-to-quadriceps strength ratio (H/QRatio) and the ROM of the knee joint among male athletes with the hamstring shortness. Design: A randomized controlled trial. Setting: Research laboratory. Participants: Twenty-four college-aged male athletes with hamstring shortness were selected for this study and were randomly assigned to a foam rolling group (FOAM, n = 12) and a control group (n = 12). Interventions: Participants in the FOAM group performed supervised self-myofascial release program 3 times per week for 8 weeks. The control group received no intervention. Methods: Data were analyzed via 2-way repeated-measure analysis of variance at the significance level of .05. Main Outcome Measures: ROM and the H/QRatio at the velocities of 60°/s, 120°/s, and 180°/s were measured by an isokinetic dynamometer. Results: The results of 2-way repeated-measure analysis of variance demonstrated that hamstring ROM increased in FOAM group (P = .001). No significant changes were found in H/QRatio after self-myofascial release for FOAM group (P ≥ .05). Conclusions: When compared with other methods of stretching, self-myofascial release with foam rolling may be beneficial in increasing ROM without decreasing H/QRatio in people with the hamstring shortness.
Ogün Köyağasıoğlu and Cengizhan Özgürbüz
Context: Mental training is a promising method to improve motor skills. However, transfer of these improvements to different skills or functional activities is still unclear. The purpose of this study was to investigate the effects of mental balance training programs on motor coordination and skill transfer. Design: Randomized controlled trial. Methods: Fifty-seven healthy adults (28 females and 29 males) aged between 18 and 25 years participated in this study. Participants were randomly assigned to 3 groups: virtual reality (VR) mental training group, conventional mental training group, and control group. The training program included action observation and motor imagery practice with balance exercise videos. The VR mental training group trained with a VR head-mounted display and the conventional mental training group trained with a nonimmersive computer monitor for 30 minutes, 3 days per week, for 4 weeks. Coordination skills were tested with 2 separate custom-made obstacle course tests (OCT-1 and OCT-2). OCT tests included crouching, turning, leaning, stepping over, changing direction, walking on various surfaces, or using repeated hand and arm movement tasks. OCT-1 was used to investigate the effects of mental exercises on coordination skills, and OCT-2 to investigate transfer effects for novel tasks. Test time (total and corrected) and error types (minor, major, and total) were recorded. Touching an obstacle without changing its position was classified as a minor error, and changing its position was a major error. Results: OCT-1 test time and number of errors significantly decreased in the VR mental training and conventional mental training groups, but not in the control group. The number of minor errors was only decreased in the VR mental training group. For OCT-2, total and corrected time were not significantly different between the groups. However, both training groups were significantly superior to the control group for all types of errors. Conclusions: Our findings suggest that both training interventions can significantly improve coordination and skill transfer test results. In addition, VR mental training may have some advantages over conventional mental training. These findings are promising for the use of mental training for prevention and rehabilitation in special populations.
Yu Konishi, Ryo Yoshii, and Christopher D. Ingersoll
Context: Quadriceps activation failure has been observed following various pathological conditions in a knee joint such as knee surgery, pain, effusion in knee, and osteoarthritis also could be aging matter. Those patients are unable to attain maximal quadriceps strength for a long period of time although their quadriceps itself is not damaged. This impairment is termed arthrogenic muscle inhibition (AMI). AMI has been of concern to clinicians because this weakness hinders the rehabilitation process considerably and delays recovery because strengthening protocols for the AMI could be largely ineffective. Clinically, it is important to understand neurophysiological mechanisms of the AMI to treat patients with the impairment. Objectives: This is a narrative review of the literature. The purpose of this review is to understand the following: (1) Why investigations of only peripheral spinal reflexive pathways are not enough for elucidation of the mechanisms of the AMI? (2) What we know about the role of the gamma spindle system in AMI so far? (3) Could a dysfunctional gamma spindle system contribute to AMI lead neural changes in upper central nervous system? and (4) Concerns that a clinician should take into consideration when deciding whether to apply therapeutic interventions for AMI. Data Sources: The databases PubMed, MEDLINE, SPORTDiscus, and CINAHL were searched with the terms arthrogenic muscle inhibition (AMI), reflex inhibition, joint mechanoreceptor, gamma loop, corticospinal pathway, spinal reflex, effusion, and joint injury. The remaining citations were collected from references of similar papers. Conclusions: AMI is a limiting factor in the rehabilitation of joint injury. Motor unit recruitment could be hindered in patients with AMI as a result of a dysfunctional gamma spindle system. Clinicians should understand the mechanism of AMI well in order to establish effective rehabilitation programs for AMI. Indeed, AMI is not caused by a single factor, but rather, multiple neural factors can change over time following the appearance of AMI. Therefore, multiple interventions targeting different neural pathways should be combined to achieve the ideal therapeutic goal for the treatment of AMI.
Orges Lena, Jasemin Todri, Ardita Todri, Luis Fernández Azorín, Juan Martínez Fuentes, Petraq Papajorgji, Sergio Hernandez Sanchez, Mercedes Castejon Castejon, Martha Cecilia León Garzón, and Jose Luis Martínez Gil
Objectives: To evaluate the efficacy of 24 weeks of treatment with Mézières method in a Spanish elite second-division soccer team with low back pain (LBP), analyzing their state of back health, flexibility, pain, and steps speed. Design:Double-blind randomized controlled trial. Methods:A total of 20 players with LBP from the second soccer division league were allocated equally to the experimental and control groups (n = 10) as per selection criteria and participated in 2 different rehabilitation programs. The postural Mézières method was implemented in the experimental group, whereas the standard European treatment protocol for LBP was implemented in the control group. Both treatments had a twice weekly session of 40 minutes duration for 24 weeks consecutively with a follow-up in the fourth, 12th, and 24th weeks. Results: Multivariate analysis of covariance with the baseline assessment as a covariance showed a significant difference between groups at the 12th and 24th weeks of the treatment for pain and back functionality. A relevant difference between the experimental and control groups was shown only at the 24th week of the treatment (P < .05) for back flexibility. A significant difference between groups was reported for the quality of life scale and steps speed at the 24th week of the treatment (P > .05). Conclusion: The Mézières method showed a positive effect in the elite soccer athletes with nonspecific chronic LBP and can be used as an alternative treatment.
Lewis King, SarahJane Cullen, Jean McArdle, Adrian McGoldrick, Jennifer Pugh, Giles Warrington, and Ciara Losty
A large proportion of jockeys report symptoms associated with mental health difficulties (MHDs), yet most do not seek help from professional mental health support services. Due to the paucity of literature in this field, this study sought to explore jockeys’ barriers to, and facilitators of, help-seeking for MHDs. Twelve jockeys participated in semistructured interviews, subsequently analyzed via reflexive thematic analysis. Barriers to help-seeking included the negative perceptions of others (stigma and career implications), cultural norms (masculinity and self-reliance), and low mental health literacy (not knowing where to seek help, minimization of MHDs, negative perceptions of treatment, and recognizing symptoms). Facilitators to help-seeking included education (exposure to psychological support at a younger age), social support (from professionals, jockeys, family, and friends), and media campaigns (high-profile disclosures from jockeys). Findings are consistent with barrier and facilitator studies among general and athletic populations. Applied recommendations and future research considerations are presented throughout the manuscript.