Relationship between exacerbating patellofemoral pain and dynamic knee valgus in females with patellofemoral pain after a patellofemoral joint loading protocol: A cross-sectional.

OBJECTIVE: The aim of the present study is to 1) the effect of exacerbating patellofemoral pain (PFP) on dynamic knee valgus (DKV) 2) the relationship between exacerbating PFP and DKV in females with patellofemoral pain. DESIGN: Cross-sectional study. METHODS: Sixty women with PFP were recruited from the orthopedic clinics. We evaluated pain intensity and DKV in two conditions without (condition 1) and with (condition 2) PFJ loading during the single-leg squat (SLS) task. The MANOVA test was used to compare pain intensity and DKV angle between the two conditions. Furthermore, the Pearson correlation was used to examine the correlation between pain intensity with DKV angle. RESULTS: The MANOVA analysis showed that pain intensity (P < 0.000, η2 = 0.623) and DKV angle (P < 0.000, η2 = 0.544) with a medium effect size significantly increased after PFJ loading. Furthermore, an excellent positive correlation was observed between an increase in pain intensity and DKV angle (P < 0.000, r = 0.840). CONCLUSION: It seems that after the PFJ loading protocol and the subsequent pain exacerbation, the neuromuscular biomechanics of the lower limb are deficits. As a result, the stabilizing muscles activation decreases and increases the lower limb movement in the frontal plane.

The effect of kinetic factors of dynamic knee valgus on patellofemoral pain: A systematic review and meta-analysis.

The speculation of dynamic knee valgus (DKV) correlates with kinetic changes in the frontal plane that increased loading patellofemoral joint (PFJ). Therefore, it is the purpose of this systematic review and meta-analysis study is the effect of kinetic factors DKV on patellofemoral pain (PFP). The search strategy was carried out in the electronic databases of Cochrane Library, PubMed, Springer Link, Science Direct, Scopus. Studies limited to the period 2000 to 2020 were extracted. The quality of study was assessment by modified Downs and Black checklist. Mean and standard deviation were also used to calculate the effect size. There were selected 8 articles for the systematic review and Meta-analysis. The results showed that in PFP patients compared to healthy individuals have increase knee abduction moment (SMD = 0.75; 95% CI = [0.47 to 1.02]) and impulse (SMD = 0.79; 95% CI = [0.50 to 1.07]). Furthermore, PFP patients compared to healthy individuals have decrease onset (SMD = -0.60; 95% CI = [-1.03 to -0.17]) and during (SMD = -0.93; 95% CI = [-1.57 to -0.29]) gluteus medius (GMED); vis-à-vis, PFP patients compared to healthy individuals have increase onset (SMD = 0.10; 95% CI = [-0.34 to 0.54]) and during (SMD = 0.29; 95% CI = [-0.15 to 0.73]) adductors longus (AL). As a result; PFP patients compared to healthy individuals show decrease co-contraction GMED/AL (SMD = -1.03; 95% CI = [-1.83 to -0.24]). The kinetic factors of DKV of leading to PFJ contact area decreases and the loading in a smaller contact area on PFJ in the outer part of the patella. Eventually, this abnormal distribution of contact pressure leads to etiology and osteoarthritis of the PFP.

The effects of virtual reality training on postural sway and physical function performance on older women with chronic low back pain: A double-blind randomized clinical trial.

BACKGROUND: Chronic low back pain (CLBP) is known as an important debilitating health condition among older women. OBJECTIVE: This study aimed to evaluate the effects of eight-week virtual reality training (VRT) exercises on postural sway and physical function performance (PFP) among older women suffering from CLBP. METHODS: Twenty-seven older women presenting with CLBP were randomized into experimental and control groups. The experimental group was instructed to perform 30-minute VRT exercises three times a week for eight weeks. Plantar pressure variables [sway velocity (SV) and anterior-posterior (AP) and medial-lateral (ML) fluctuations of the center of pressure (CoP)], 30-second chair stand test (30CST), and timed up and go (TUG) test were recorded. RESULTS: The VRT group exhibited significant decreases in SV (p= 0.002), AP (p= 0.008), and ML (p= 0.02) fluctuations. Also, the performance of the VRT group in the 30CST and TUG tests significantly improved after the exercises (P< 0.001). CONCLUSION: According to the results, VRT and the program used in this study should be used to enhance balance and PFP in older women with CLBP who mostly prefer activities that are accessible and feasible in low-risk environments.

Adding Neurofeedback Training to Neuromuscular Training for Rehabilitation of Chronic Ankle Instability: A 3-Arm Randomized Controlled Trial.

BACKGROUND: Neurofeedback training (NFT) can aid in the treatment of the abnormal patterns of the brain brought on by physical injury, enhancing cognitive and behavioral abilities. The present study aimed to compare the effectiveness of combining neuromuscular training (NMT) and NFT (NMT+NFT) with NMT alone in rehabilitating athletes with chronic ankle instability (CAI). HYPOTHESIS: NMT+NFT will be more effective than NMT alone. STUDY DESIGN: A 3-arm, single-blind randomized controlled trial. LEVEL OF EVIDENCE: Level 2. METHODS: A total number of 62 athletes, aged 18 to 25 years, with CAI, participated in this study. The study subjects were allocated randomly to 3 groups: 21 cases in the control group, 21 cases in the combination group (CG) receiving NMT+NFT, and 20 cases in the neuromuscular group (NG) practicing NMT alone, undergoing exercises related to their groups for 8 weeks. Data were recorded and analyzed before and after the 8-week training program. The primary outcome measures were postural sway indices; secondary outcomes included ankle proprioception and biopsychosocial indices. RESULTS: NMT+NFT was more effective than NMT alone in terms of improving postural control during single- and 2-legged standing positions under the conditions of eyes closed and eyes open, proprioception at 20° of plantar flexion, as well as anxiety and depression in athletes with CAI. However, the findings revealed that NMT+NFT and NMT alone could both improve such indices. CONCLUSION: NMT+NFT as a treatment protocol improved postural control, ankle proprioception, anxiety, and depression greater than NMT alone. CLINICAL RELEVANCE: A combined protocol of NFT and NMT led to greater improvement compared with NMT alone. NFT was recommended as an adjunct therapy in the rehabilitation of athletes suffering from CAI.

The Effects of FIFA 11+ Kids Prevention Program on Kinematic Risk Factors for ACL Injury in Preadolescent Female Soccer Players: A Randomized Controlled Trial.

This study aimed to investigate the effects of the 8-week FIFA 11+ Kids program on kinematic risk factors for ACL injury in preadolescent female soccer players during single-leg drop landing. For this, 36 preadolescent female soccer players (10-12 years old) were randomly allocated to the FIFA 11+ Kids program and control groups (18 players per group). The intervention group performed the FIFA 11+ Kids warm-up program twice per week for 8 weeks, while the control group continued with regular warm-up. Trunk, hip, and knee peak angles (from initial ground contact to peak knee flexion) were collected during the single-leg drop landing using a 3D motion capture system. A repeated measure ANOVA was used to analyze groups over time. Significant group × time interactions were found for the peak knee flexion, with a medium effect size (p = 0.05; effect size = 0.11), and peak hip internal rotation angles, with a large effect size (p < 0.01; effect size = 0.28). We found that the FIFA 11+ Kids program was effective in improving knee flexion and hip internal rotation, likely resulting in reducing ACL stress during single-leg drop landing in young soccer players.

The effect of mindfulness and motivational interviewing along with neuromuscular exercises on pain, function, and balance of women affected by knee osteoarthritis: a rater-blinded randomized controlled clinical trial.

PURPOSE: This study aimed to evaluate the effect of motivational interviewing (MI) and mindfulness (MF) added to neuromuscular (NM) exercises on improving pain, function, balance, and quality of life in patients with knee osteoarthritis (KOA). METHODS: This randomized clinical trial was conducted on sixty patients who were randomly assigned to the MI + NM, MF + NM, and NM groups. The groups received four training sessions for six weeks. Physical function with Western Ontario and McMaster Universities Arthritis Index timed up and go, going up and down eight stairs, pain with visual analogue scale, quality of life with SF36, and balance with Biodex were evaluated before and after interventions. RESULTS: Within-group comparisons showed that NM + MI, NM + MF, and NM groups experienced significant improvement in all factors after six-week (p < 0.05). However, between groups, comparisons in the post-test revealed that the MI + NM group had a more significant effect on pain, function, and static balance than the MF + NM group. Nevertheless, the MF + NM group improved the quality of life better than the MI + NM and NM groups (p < 0.05). CONCLUSION: Adding psychological interventions to physical exercises had a better effect on improving the symptoms of patients. Additionally, the MI showed more effectiveness in improving the symptoms of patients.IMPLICATIONS FOR REHABILITATIONAdding motivational interviewing to neuromuscular exercises has shown to reduce pain intensity and improved function, balance and quality of life in adults with knee osteoarthritis.Adding mindfulness intervention to neuromuscular exercises has shown to reduce pain intensity and improved function, balance and quality of life in adults with knee osteoarthritis.Among the psychological interventions used, the motivational interviewing significantly showed more effectiveness in improving the pain, function, balance, and quality of life of patients with osteoarthritis.

Effect of foot orthoses on dynamic balance in taekwondo athletes with flexible flatfoot: A randomized controlled trial.

BACKGROUND: Flexible flatfoot (FFF) cause biomechanical and sensorimotor disorders of the foot and ankle complex and reduce of postural stability. Postural stability is an important movement skill that affects the performance of taekwondo (TKD) athletes and can lead to fall injuries. The purpose of this study is the effect 12-week application of foot orthosis (FOs) on dynamic balance in TKD athletes with FFF. METHOD: In this trial, 30 girls of the TKD athletes with FFF were recruited. They were randomly assigned to experimental and control groups (15 subjects in each group). The experimental group used FOs with medial longitudinal arch support for 12 weeks, and the control group did not have any intervention. The outcome measures include navicular drop and balance in three directions: anterior-posterior, medial-lateral and overall stability. Covariance analysis was used to compare the results between two groups. RESULTS: The covariance results showed that the experimental group compared to the control group with a high effect size had a significant difference in reducing of navicular drop (P = 0.000, ηp2 =0.512), anterior-posterior sway (P = 0.000, (ηp2 =0.397) medial-lateral sway (P = 0.019, ηp2 = 0.186) and overall stability sway (P = 0.008, ηp2 = 0.232). CONCLUSIONS: The FOs with medial longitudinal arch support leads to FFF correction and provides mechanical stability of the foot and ankle complex. Also, the impulses sent from plantar receptors are increased and a better understanding of postural sway is transmitted to the central nervous system and balance strategies are improved.

Patients with Patellofemoral Pain Exhibiting Decrease Vertical Ground Reaction Force Compared to Healthy Individuals during Weight Bearing Tasks: A Systematic Reviews and Meta-Analysis.

Background: Vertical ground reaction force (VGRF) can lead to the development knee osteoarthritis. This review systematic and meta-analysis aimed to investigate the VGRF in patellofemoral pain patients (PFP) during weight bearing tasks. Methods: Search strategy was conducted in databases: Science Direct, Scopus, PubMed and Google Scholar from Sep 2020 to Jun 2021. The VGRF components we measured were passive impact (Fz1)/peak and propulsion/active peak (Fz2). The quality of the studies was evaluated with Down and Black index and it was divided into three groups: low quality (LQ), medium quality (MQ) and high quality (HQ). The standardized mean difference between PFP and healthy individuals was used to calculate the effect size. Results: Nine articles were selected for systematic review and meta-analysis of which 5 studies was HQ, 3 studies were MQ and 1 study was LQ were classified. PFP compared to healthy individuals with moderate and small effect size have reduced impact and propulsion respectively. Conclusion: The in PFP, VGRF is influenced psychological, behavioral and biomechanical factors. Therefore, psychosomatic therapeutic approaches may have a long time effectiveness on the rehabilitation of PFP.

Comparing the effects of suspension and isometric-isotonic training on postural stability, lumbopelvic control, and proprioception in women with diastasis recti abdominis: a randomized, single-blinded, controlled trial.

BACKGROUND: Diastasis recti abdominis (DRA) affects a significant number of women in the postpartum period. OBJECTIVE: This study compared the effectiveness of suspension training system (STS) with that of isometric-isotonic (ISoM-ISoT) exercises in the treatment of DRA and its secondary complications. METHODS: Thirty-six women with DRA participated in this study. They were divided into the three groups of STS, ISoM-ISoT, and control. Inter-recti distance (IRD), proprioception, lumbopelvic control, postural stability, low back pain, and disability were assessed using a digital caliper, a goniometer, a lateral step-down test, a Biodex balance system, a visual analogue scale (VAS), and the Oswestry Disability Index (ODI), respectively. Two intervention groups underwent training for 8-week and the control group resumed their normal lives. RESULTS: Positive effects were observed in the STS and ISoM-ISoT groups compared with the control group in: IRD (P = .001); lumbopelvic proprioception (P = .001); lumbopelvic control (P = .001); overall static balance (P = .010); overall dynamic balance (P = .012); low back pain (P = .001); and disability (P = .001). However, there was no significant difference between the training groups in: IRD (P = .12, MD = -2.76); lumbopelvic proprioception (P = .48, MD = -0.50); lumbopelvic control (P = .14, MD = 1.53); static balance (P = .62, MD = 0.07); dynamic balance (P = .27, MD = 0.33); pain (P = .25, MD = -0.52); and disability (P = .48, MD = -1.74). The results of the minimal clinically important difference (MCID) and minimal detectable change (MDC) suggested that the STS exercises outperformed ISoM-ISoT training regarding IRD, pain, disability, and proprioception, whereas ISoM-ISoT training had a better effect in lumbopelvic control and balance. CONCLUSION: The results of our study showed that the STS had a positive effect on women with DRA and like the ISoM-ISoT exercises can be used to treat this dysfunction.

Bilateral symmetry of vertical time to stabilization in postural sway after double-leg landing in elite athletes with unilateral chronic ankle sprain.

BACKGROUND: Lower limb asymmetry among athlete with unilateral chronic ankle instability (CAI) during bilateral landing can be a potential source of ankle sprain reinjury. The aim of study was to investigate the effect of bilateral symmetry of vertical time to stabilization (vTTS) in postural sway after double-leg landing (DLL) in elite athletes with unilateral CAI. METHODS: Twenty professional players with unilateral CAI and ten healthy controls were assigned to three groups (soccer, basketball, and control groups, n = 10 each). The postural balance during DLL tasks was assessed based on center of pressure (CoP) and vTTS. Multiple analysis of variance was conducted to statistically analyse the CoP and vTTS which followed by Bonferroni's post hoc test (P < 0.05). RESULTS: The vTTS of the injured foot was significantly longer in the soccer and basketball players than in the control players (P = 0.006, p < 0.001 respectively). The intragroup comparison showed a significant difference in the vTTS of CAI and uninjured feet among the basketball players (mean difference = 1.3 s). The basketball group exhibited a worse balance in CoP oscillations results between groups. CONCLUSIONS: The findings suggested that symmetry between double-leg vTTS values, may be important as much as the sooner vTTS in reduced CoP oscillations and enhanced balance after DLL. Balancing exercises should achieve sooner vTTS in soccer players and symmetry in the double-leg vTTS of basketball players with unilateral CAI while maintaining static balance during dynamic-to-static postural changes to reduce recurrent ankle sprain.

Effects of an 8-Week Virtual Reality Training Program on Pain, Fall Risk, and Quality of Life in Elderly Women with Chronic Low Back Pain: Double-Blind Randomized Clinical Trial.

Objective: Low back pain (LBP) and falls are among the major problems experienced by the elderly population. The present study investigated the effectiveness of an 8-week virtual reality training (VRT) program in helping relieve pain, minimize fall risk, and improve quality of life (QoL) in elderly women suffering from chronic LBP (CLBP). Materials and Methods: Twenty-five elderly women (VRT/intervention group = 13, control group = 12) with CLBP and aged 65 to 75 years were recruited. The VRT involved three 30-minute weekly sessions of exercises that were carried out using the Xbox Kinect headset. Pain intensity, fall risk, and QoL were assessed via the Visual Analog Scale, the Biodex Balance System, and the 36-Item Short Form Health Survey, respectively. Results: The outcomes of a one-way analysis of covariance indicated that the pain intensity score of the intervention group significantly decreased after participation in the VRT program (P = 0.001). The intervention group also showed reduced fall risk (P = 0.001) and elevated QoL (P = 0.001). Conclusion: The results confirmed that the VRT program can be regarded as a valid therapeutic intervention that helps reduce patients' symptoms and increase the effectiveness of exercises in the elderly by teaching pain-related insight as well as enhancing QoL and reduce fall risk through various movements.

The effect of self-reported knee instability on plantar pressure and postural sways in women with knee osteoarthritis.

BACKGROUND: Giving way and knee instability are common problems in patients with knee osteoarthritis, disrupting the daily activities and balance of the affected individual. The present study aimed to evaluate the postural control status of women with knee osteoarthritis with and without self-report knee instability (KI). METHODS: This cross-sectional, single-blind study was conducted on 57 female patients with knee osteoarthritis. The patients were selected based on the inclusion and exclusion criteria and divided into two groups of with KI (n = 26) and without KI (n = 31). Fear of movement was assessed using the Tampa questionnaire, the degree of knee instability was measured based on the Fitzgard scale, the static and dynamic balance of the subjects were evaluated with open and closed eyes using a Biodex balance device, and foot pressure distribution situation was measured using a FDM-S-Zebris device. RESULTS: Mean comparison showed a significant difference between the subjects with and without KI in static balance only in anterior-posterior direction with open eyes (p = 0.01) and closed eyes (p = 0.0001). In the dynamic balance test, the subjects in both groups had significant differences in terms of all the indicators of anterior-posterior stability (p = 0.001), medial-lateral stability (p = 0.0001), and overall stability (p = 0.0001) with closed eyes. However, no significant difference was observed with open eyes (p > 0.05). Multiple regression also indicated significant positive correlations between pain intensity and disease duration with the degree of KI (p < 0.05). CONCLUSIONS: According to the results, there were significant differences between the mean pain scores, static and dynamic balance, and the rate of fall between the women with knee osteoarthritis with and without the KI index. Therefore, patients with knee osteoarthritis, which also has an index of KI, are more susceptible to falls, and proper strategies are required to reduce the level of KI in these patients.

Prophylactic ankle supports effects on time to stabilization, perceived stability and ground reaction force during lateral landing in female collegiate athletes with chronic ankle instability.

BACKGROUND: This study was designed to investigate effects of Kinesiotape (KT) with closed basket weave method and lace-up braces (LB) on the vertical time to stabilization, peak vertical ground reaction force (PvGRF), and time to PvGRF as well as perceived stability during lateral landing of participants with chronic ankle instability before and after fatigue. METHODS: Thirty female college athletes with chronic ankle instability of three conditions (control, KT, and LB) performed lateral landing from a 30 cm high step on the plantar pressure platform pre and post fatigue. RESULTS: The pre-test findings on the rearfoot, of LB indicated negatively increased the PvGRF force (F2,58=3.63, P = 0.04) and decreased the time to PvGRF (F2,58=4.67, P = 0.01). The Bonferroni post-hoc testing revealed LB condition increased the PvGRF than the control (P = 0.002) and KT (P = 0.038). Also, the post-hoc testing showed LB condition decreased the time to PvGRF force than the control (P = 0.05) and KT (P = 0.01). The LB negatively prolonged vertical time to stabilization in the forefoot (F2,58=6.74, P = 0.002) and rearfoot (F2,58=6.13, P = 0.004) after fatigue. The post-hoc testing revealed LB condition generated a slower vertical time to stabilization than the control and KT conditions (P ≤ 0.05). The use of KT had no positive effects as elevated the PvGRF in the forefoot post fatigue (F2,58=7.11, P = 0.002). The post-hoc test uncovered that KT augmented the PvGRF than control (P = 0.01) and LB (P < 0.001). On the other hand, using KT had psychological effects at pre-fatigue which resulting significantly greater in perceived stability compared to other conditions (F2,58=9.65, P < 0.001). The post-hoc test showed that using KT increased perceived stability than LB (P = 0.004) and control (P < 0.001). Moreover, perceived stability improved significantly in KT and LB compared to the control condition at the post-fatigue (P ≤ 0.001). CONCLUSIONS: Despite the positive psychological impact of the prophylactic ankle supports, there were no positive effect on the vertical time to stabilization, PvGRF, and time to PvGRF. Further studies are needed to distinguish the psychological and actual effects of prophylactic ankle supports on athletes with chronic ankle instability.

Anatomical risk factors of lateral ankle sprain in adolescent athletes: A prospective cohort study.

OBJECTIVES: The purpose of this study was to identify prospectively the anatomical and functional intrinsic risk factors for lateral ankle sprain (LAS) in adolescent athletes participating in team sports. DESIGN: A prospective cohort study. SETTING: University research laboratory. PARTICIPANTS: A total of 152 adolescent male athletes (age: 14.45 ± 2.96 years; height: 165.63 ± 15.33 cm; weight: 55.60 ± 16.56 kg; body mass index: 19.97 ± 3.58 kg/m2) participated in this study. MAIN OUTCOME MEASURES: The participants were assessed during the preseason for previous ankle sprain history, navicular drop, tibia vara, Q angle, tibia torsion, knee recurvatum, and ankle ROM. LASs were prospectively recorded and diagnosed for two consecutive seasons (20 months). RESULTS: Previous ankle sprain history (odds ratio [OR] = 60.911, p < 0.001), increased navicular drop (OR = 1.767, p < 0.001), and knee recurvatum (OR = 1.881, p = 0.002) were positively associated with the incidence of LAS. The receiver operating characteristic (ROC) analyses revealed the predictive potentials of previous ankle sprain history (the area under the ROC [AUROC] = 0.706, p < 0.001), navicular drop (AUROC = 0.906, p < 0.001), and knee recurvatum (AUROC = 0.724, p < 0.001). CONCLUSION: Athletes with previous ankle sprain history, knee recurvatum, and especially navicular drop may have a greater risk of LAS injury. The data from this study can help therapists and trainers to identify people with a higher risk of LAS.

Eight-Week Inspiratory Muscle Training Alters Electromyography Activity of the Ankle Muscles During Overhead and Single-Leg Squats: A Randomized Controlled Trial.

This study was conducted to evaluate the effects of 8-week inspiratory muscle training on activity in the ankle muscles of athletes with chronic low-back pain. A randomized controlled trial involving 45 men and women with chronic low-back pain was carried out. Electromyography activity in the tibialis anterior, peroneus longus, gastrocnemius medialis, and gastrocnemius lateralis muscles of the dominant leg was recorded. Secondary outcomes included biopsychosocial indices, such as pain, disability, anxiety and depression, fear-avoidance beliefs, and fear of (re)injury. Static and dynamic overhead squat tests showed that inspiratory muscle training decreased activity in the tibialis anterior, peroneus longus, and gastrocnemius medialis muscles. In the static single-leg squat test and the descending phase of the dynamic equivalent, such a decrease was observed in all the 4 muscles. Inspiratory muscle training significantly reduced pain severity and activity in the tibialis anterior, peroneus longus, and gastrocnemius medialis muscles during the ascending phase of the dynamic single-leg squat test. On the basis of the findings, 8 weeks of inspiratory muscle training may constitute useful rehabilitation for reducing excessive activity in ankle joint muscles and aiding chronic low-back pain recovery.

Effects of eight-week water versus mat pilates on female patients with chronic nonspecific low back pain: Double-blind randomized clinical trial.

OBJECTIVE: To evaluate the effects of water and mat Pilates on pain, disability, and static and dynamic balance in patients with chronic nonspecific low back pain (CNLBP). METHODS: Twenty-four participants with CNLBP were randomly allocated into two groups (n = 12) that perform water and mat Pilates exercises for 24 sessions (8-week, 3 sessions per week). The value for pain, disability and balance were measured before and after the exercise program using the Visual Analogue Scale, Oswestry Disability Questionnaire and Biodex Balance System respectively. RESULTS: A paired t-test revealed significant differences in pain severity and disability in both groups after they performed the Pilates program (P ≤ 0.05). Mat Pilates improved static balance as the participants performed the tests with their eyes open and closed (P = 0.02, P = 0.04). Its effect on dynamic balance, however, was not statistically significant (ES = 0/33, P = 0/34). The same Pilates program performed in water did not show significant effects on balance despite a decline in body sway (P˃0/05). There was no difference between the two groups (P˃0/05). CONCLUSION: The results suggest that both mat and water Pilates exercise program have beneficial effects on the treatment of LBP. Nevertheless, the low impact of the mat and water Pilates program on balance improvement suggests more investigation on Pilates training or complementary exercises to improve balance in patients with CNLBP.

Inspiratory Muscle Training in Rehabilitation of Low Back Pain: A Randomized Controlled Trial.

CONTEXT: People with chronic low back pain (CLBP) suffer from weaknesses in their core muscle activity and dysfunctional breathing. Inspiratory muscle training (IMT) was recently developed to treat this condition. OBJECTIVES: The present study was conducted to investigate the effect of IMT on core muscle activity, pulmonary parameters, and pain intensity in athletes with CLBP. DESIGN: This study was designed as a single-blind, randomized, controlled trial. SETTING: Clinical rehabilitation laboratory. PARTICIPANTS: A total of 23 male and 24 female athletes with CLBP were randomly divided into the experimental and control groups. MAIN OUTCOME MEASURES: The experimental group performed IMT for 8 weeks, 7 days per week and twice daily, using POWERbreathe KH1, beginning at 50% of maximum inspiratory pressure with a progressively increasing training load. The surface electromyography muscle activity of the erector spinae, multifidus, transverse abdominis and rectus abdominis, respiratory function and Visual Analogue Scale score were also measured before and after the intervention in both groups. The repeated-measures analysis of variance and 1-way analysis of covariance were further used to compare the intragroup and intergroup results following the intervention. RESULTS: The findings of the study revealed that multifidus and transverse abdominis activity, as well as respiratory function, increased significantly in the IMT group (P < .05). Moreover, a descending trend was observed in the Visual Analogue Scale score in the experimental group (P < .05). CONCLUSION: The results showed that IMT can improve respiratory function, increase core muscle activity, and, consequently, reduce pain intensity in athletes with CLBP.

Effect of respiratory muscle training session on ankle muscle activity in athletes with chronic low back pain performing overhead squats: a randomized controlled trial.

AIM: The current study was conducted to evaluate the effect of a respiratory muscle training session on ankle muscle activity in athletes with chronic low back pain performing overhead squats. METHODS: The current double-blind, randomized, controlled trial was conducted on 24 patients randomly selected as the training group and 23 patients as the control group. The training group received the respiratory muscle training protocol. The electromyography activity of the tibialis anterior, peroneus longus, gastrocnemius medialis and gastrocnemius lateralis muscles of the dominant leg was recorded in the participants. RESULTS: The findings showed that a session of respiratory muscle training reduced the activities of some ankle joint muscles when performing overhead squats, including tibialis anterior in the static and dynamic overhead squat tests and peroneus longus in the ascending phase. In the dynamic test, the angle to reach peak activity changed in tibialis anterior in the descending phase and also in tibialis anterior and peroneus longus in the ascending phase. CONCLUSION: Effects of respiratory muscle training prevented excessive ankle joint muscle activity through stimulating local muscles while performing overhead squats, which had indicated an improved postural control and multisectional proprioception to maintain postural stability and stimulated the local muscles of the core area.

Reduction of postural sway in athletes with chronic low back pain through eight weeks of inspiratory muscle training: A randomized controlled trial.

BACKGROUND: Postural control and respiratory function are mechanically and neuromuscularly dependent on each other. The present study was conducted to determine the effects of inspiratory muscle training on postural sway in athletes with chronic low back pain. METHODS: Twenty-four patients were randomly selected as the experimental group and 23 patients as the control group. The experimental group underwent the inspiratory muscle training protocol for eight weeks, seven days per week and twice daily. The postural sway variables were recorded using a plantar pressure measurement device. The postural sway variables were recorded when performing overhead and single leg squat. Patient's perceived low back pain was assessed using Visual Analog Scale. Disability was assessed using the Athletes Disability Index questionnaire. Patient depression/anxiety was assessed using the Patient Health Questionnaire-4. FINDINGS: The results of the two-way ANOVA in the overhead squat test showed that postural sway indices significantly decreased in the experimental group after 8-weeks intervention compared to the pre-test values. The results of the two-way ANOVA in single leg squat test showed significant differences between the pre- and post-test in the experimental group in the postural sway indices except for the factor of standard deviation Y, also compared to the pre-test value, pain was significantly decreased in the experimental group. INTERPRETATION: The 8-weeks inspiratory muscle training decreased postural sway in athletes with chronic low back pain when performing the overhead and single leg squat. In addition, the pain index decreased after 8-weeks of inspiratory muscle training.

Electromyographic analysis of shoulder girdle muscle activation while performing a forehand topspin in elite table tennis athletes with and without shoulder impingement syndrome.

BACKGROUND: Shoulder impingement syndrome is considered to be associated with an altered muscular activity, which is related to strategy changes in the movement plan. The present study aimed to investigate the differences in timing and intensity of activity of shoulder girdle muscles while performing a forehand topspin loop between elite table tennis players with and without shoulder impingement syndrome. The timing and activity amplitude of these shoulder girdle muscles have not been evaluated in other studies in table tennis elite athletes. METHODS: Activation timing and activity levels of the upper trapezius, lower trapezius, and serratus anterior, anterior deltoid, supraspinatus, and biceps brachii muscles were measured in 30 table tennis players (Premier League tournament level or higher) with shoulder impingement syndrome and compared with 30 same-level healthy players while performing the forehand topspin loop. RESULTS: The results indicated that the activity levels of the serratus anterior (P = .007) and supraspinatus (P = .001) muscles significantly decreased; however, the activity level of the upper trapezius significantly increased in the impingement compared with the healthy group (P = .009). The serratus anterior (P = .001) was activated significantly later, but the upper trapezius (P = .004) was activated significantly earlier in the impingement group. CONCLUSION: Results of the present study support the theory that the activation and sequence of recruiting of the shoulder muscles are altered in people with impingement symptoms, suggesting that impingement syndrome may be associated with disturbed timing and activity level of shoulder girdle muscles.