Extension Exercise Research Articles

Sex differences in the peripheral determinants of oxygen uptake in heart failure with preserved ejection fraction

Abstract Background A hallmark feature of heart failure with preserved ejection fraction (HFpEF) is exercise intolerance. Data from non-invasive, whole-body cardiopulmonary exercise testing indicates that females with HFpEF have reduced VO2 secondary to a to lower cardiac output and arterial-to-venous oxygen content difference (∆a-vO2) at maximal effort compared to males with HFpEF [1]. Thus, in addition to cardiac limitations, peripheral/non-cardiac limitations may be important contributors to reduced peak aerobic power (VO2) in females with HFpEF; however, these peripheral mechanisms of exercise intolerance are not fully understood. Given that HFpEF disproportionately affects older females, identifying sex differences in the limitations to exercise is especially important. Purpose Using dynamic single leg knee extension (SLKE) exercise to isolate peripheral determinants of oxygen transport and utilization, we sought to test the hypothesis that females with HFpEF have lower leg VO2 at peak SLKE resulting from smaller increases Δa-vO2 and muscle oxygen diffusive conductance (DMO2) compared to males. Methods Eighteen females (69 ± 7 years) and 13 males (73 ± 6 years) with HFpEF performed a maximal SLKE exercise test on a custom ergometer. LBF (duplex Doppler ultrasound) was measured at the common femoral artery and leg VO2 was determined as the product of LBF and ∆a-vO2 (femoral venous catheter). DMO2 was calculated as leg VO2/2x leg venous oxygen pressure (PvO2). Thigh lean and fat mass (TLM and TFM, respectively) was measured using dual energy x-ray absorptiometry. Group differences between the two sexes were compared using an unpaired t-test and significance was set at p<0.05. Results Body mass, body mass index, and TLM were not different between groups (p > 0.05 for all), however TFM was higher in females (p<0.001; Table 1). At rest, ∆a-vO2 was lower in females (p = 0.001), whereas heart rate, mean arterial blood pressure, femoral LBF, and leg VO2 were not different between groups (p>0.05 for all; Table 1). Peak workload was lower in females compared to males (13 ± 5 vs 20 ± 7 watts, p = 0.011). At peak SLKE, leg VO2 was lower in females (185 ± 57 vs 286 ± 91 ml/min, Figure 1) due to lower ∆a-vO2 (9.7 ± 1.8 vs 12.3 ± 2.5 ml O2/dl blood, p = 0.003) and LBF (1918 ± 576 vs 2382 ± 872 ml/min, p = 0.084). DMO2 at peak SLKE was also lower in females (3.6 ± 1.2 vs 6.3 ± 1.8 ml/min/mmHg, Figure 1) suggesting sex differences in both convective and diffusive oxygen transport. Moreover, when normalized to TLM, the difference in peak leg VO2 between the sexes persisted (28.2 ± 6.5 vs 41.5 ± 10.9 ml/kg/min; p = 0.004). Conclusion These data highlight that that the lower peak oxygen extraction (∆a-vO2) and diffusion (DMO2) in females with HFpEF contribute to sex-dependent differences in exercise intolerance. Further studies investigating potential sex-specific impairments in the muscle-vascular interface in HFpEF are warranted.Table 1Figure 1

Abstract 13736: Whole Body versus Small Muscle Mass Exercise Training in Patients With Heart Failure With Preserved Ejection Fraction: Impact on Peripheral Responses to Exercise

Background: Patients with heart failure with preserved ejection fraction (HFpEF) have reduced peak aerobic power (VO 2 ) during whole body exercise due in part to smaller increases in blood flow (BF) and arterial-to-venous oxygen difference (Δa-vO 2 ). We recently demonstrated that 8wks of single leg knee extension (SLKE) exercise training was effective in improving whole body VO 2 by increasing Δa-vO 2 in HFpEF; whether SLKE training induces greater peripheral adaptations compared to traditionally prescribed whole-body (i.e., cycle) training is unknown. Hypothesis: SLKE training will result in larger improvements in peak leg VO 2 , leg BF, and Δa-vO 2 during a SLKE peak exercise test vs cycle training. Methods: We recruited 16 patients with HFpEF (71 ± 6yr, 5 males) and randomized them to cycle or SLKE training 3-4 days/wk for 16wk. Before and after the intervention we quantified leg BF (ultrasound), femoral venous O 2 partial pressure (PvO 2 ) and saturation (IV catheter) during incremental SLKE peak exercise to determine peak leg VO 2, Δa-vO 2, and skeletal muscle diffusive conductance (DMO 2 ; leg VO 2 /[2x leg PvO 2 ]). Results: SLKE (n=9) and cycle (n=7) groups were matched for age and sex. Both groups increased peak workload during the SLKE exercise test (34±8%; mean ± SE; p=0.005). There was a main effect of training such that peak DMO 2 improved in both groups (cycle: 45±19%; SLKE: 12±3%; see Figure 1 ). Peak Δa-vO 2 also improved (main effect of training, p=0.002); however, this was greater in response to cycle compared to SLKE training (12±3% vs 3±2%; interaction effect, p=0.035). Conclusion: These preliminary data indicate that both types of training improve leg DMO 2 ; however, greater improvements in O 2 extraction occurred with cycle training. The differences in the peripheral adaptations may be attributed to a larger exercise “dose” in the cycle trained group. This data highlights that both modalities are effective components of exercise prescription for patients with HFpEF.

Chimney Jump and Standing Leg Extension Training Increases the Lower Extremity Power of Volleyball Athletes

Background. The Covid-19 pandemic has caused various adaptations in the world of sports. One form of adaptation that is carried out is training at home or known as training from home (TFH). Study purpose. This study aims to see the effectiveness of the chimney jump and standing leg extension exercises carried out by volleyball athletes during training at home or training from home (TFH). Materials and methods. A total of 36 volleyball athletes with an age range of 19–20 years were selected by purposive sampling and divided into the chimney jump (KCJ) group, the standing leg extension (KSE) group, and the control group (KKL). This research is quantitative research with a quasi-experimental research design with one group pretest posttest design. The three variables used as the dependent variable are agility, balance, and athlete’s leg power which were measured before TFH and after the athlete carried out TFH for 3 months. The results of the exercise were analyzed descriptively and continued to be analyzed using the Independent Samples T-test and One-Way ANOVA. Results. There was a significant difference in the results of the leg power posttest of the three groups (<.05) with KCJ having the highest average leg power (77.76 ± 9.38). Furthermore, KSE has the highest average in agility (56.83 ± 11.93) and balance (38.75 ± 3.02). Conclusions. Based on the results of this study, it can be concluded that the chimney jump has a significant impact on increasing leg power. On the other hand, the standing leg extension has a positive impact on increasing agility and balance.

Clinical value of ankle flexion and extension exercises combined with a psychological intervention in knee osteoarthritis.

Considering the limited effectiveness of clinical interventions for knee osteoarthritis (KOA), it is necessary to continue to explore appropriate and effective treatment strategies to improve the condition of KOA patients. To clarify the influence of ankle flexion and extension exercises combined with a psychological intervention on the psychological status and activities of daily living (ADLs) of patients with KOA. The research participants were 116 KOA patients admitted to The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine between May 2019 and May 2022, including 54 patients receiving routine treatment, care and psychological intervention (control group) and 62 patients additionally treated with ankle flexion and extension exercises (research group). The two groups were comparatively analyzed in terms of psychological status (Self-rating Anxiety/Depression Scale, SDS/SAS), ADLs, knee joint function (Lysholm Knee Scoring Scale), pain (Visual Analog Scale, VAS), fatigue (Multidimensional Fatigue Inventory, MFI), and quality of life (QoL; Short-Form 36 Item Health Survey, SF-36). After evaluation, it was found that the postinterventional SDS, SAS, VAS, and MFI scores in the research group were significantly reduced compared with the baseline (before the intervention) values and those of the control group, while the postinterventional Lysholm, ADL and SF-36 scores were markedly elevated. Therefore, ankle flexion and extension exercises are highly effective in easing negative psychological status, enhancing ADLs, daily living ability, knee joint function and QoL, and relieving pain and fatigue in KOA patients, thus warranting clinical promotion.

Electromyographic characterization of limb flexion, extension and their special exercise movements in high level distance runners

Abstract The study of EMG characteristics of high-level distance runners in limb flexion, extension, and their special exercise movements is beneficial to developing competitive distance running sports. In this study, high-level distance runners were used as the research object, and the sEMG test in EMG analysis was used to compare the general distance runners, and the changes of MPF, FC, and IEMG were obtained during the limb flexion, extension, and special exercise movements of high-level distance runners. When the FC was 100Hz, the MPF values of high-level distance runners were 64MV2/Hz, while the MPF values of average-distance runners were 45 MV2/Hz. When the muscle strength reached 50%, the IEMG values of rectus abdominis, biceps femoris, and gastrocnemius were 52%, 45 and 56%, respectively, in high-level distance runners, while the IEMG values of average distance runners were 47%, 42%, and 50%, respectively and 50%, respectively. Through the data analysis, the high-level long-distance runners could maintain a higher exercise state and perform at a stable level despite the gradual muscle fatigue, their muscle strength and contraction ability were stronger, and their explosive muscle power and potential were greater than the average long-distance runners.

A novel smart somatosensory wearable assistive device for older adults' home rehabilitation during the COVID-19 pandemic.

Due to the Coronavirus disease 19 (COVID-19) related social distancing measures and health service suspension, physical activity has declined, leading to increased falling risk and disability, and consequently, compromising the older adult health. How to improve the quality of older adult life has become a crucial social issue. In traditional rehabilitation, manual and repetitive muscle training cannot identify the patient's rehabilitation effect, and increasing the willingness to use it is not easy. Therefore, based on the usability perspective, this study aims to develop a novel smart somatosensory wearable assistive device (called SSWAD) combined with wireless surface electromyography (sEMG) and exergame software and hardware technology. The older adult can do knee extension, ankle dorsiflexion, and ankle plantar flexion rehabilitation exercises at home. Meanwhile, sEMG values can be digitally recorded to assist physicians (or professionals) in judgment, treatment, or diagnosis. To explore whether the novel SSWAD could improve the older adult willingness to use and motivation for home rehabilitation, 25 frail older adult (12 males and 13 females with an average age of 69.3) perform the rehabilitation program with the SSWAD, followed by completing the system usability scale (SUS) questionnaire and the semi-structured interview for the quantitative and qualitative analyses. In addition, we further investigate whether the factor of gender or prior rehabilitation experience would affect the home rehabilitation willingness or not. According to the overall SUS score, the novel SSWAD has good overall usability performance (77.70), meaning that the SSWAD makes older adult feel interested and improves their willingness for continuous rehabilitation at home. In addition, the individual item scores of SUS are shown that female older adult with prior rehabilitation experience perform better in "Learnability" (t = 2.35, p = 0.03) and "Confidence" (t = -3.24, p = 0.01). On the contrary, male older adult without rehabilitation experience are more willing to adopt new technologies (t = -2.73, p = 0.02), and perform better in "Learnability" (t = 2.18, p = 0.04) and "Confidence" (t = -3.75, p < 0.001) with the SSWAD. In addition, the result of the semi-structured interview shows that the operation of the SSWAD is highly flexible, thus reducing older adult burden during the rehabilitation exercise and using them long-term. This novel SSWAD receives consistently positive feedback regardless of the gender or prior rehabilitation experience of elders. The SSWAD could be used as a novel way of home rehabilitation for elders, especially during the COVID-19 pandemic. Older adult can do rehabilitation exercises at home, and physicians could make proper judgments or adjust suitable treatments online according to the sEMG data, which older adult can know their rehabilitation progress at the same time. Most importantly, older adult do not have to go to the hospital every time for rehabilitation, which significantly reduces time and the risk of infection.

Effectiveness of Blackburn Exercise with Thoracic Extension Exercises Versus Thoracic Extension Exercise on Postural Hyper Kyphosis and Scapula Position in Young Asymptomatic Individuals - A Comparative Study

BACKGROUND: The spine is composed of two types of curvature: kyphosis and lordosis. Postural hyper kyphosis is the most common posture abnormality and can happen at any age. Causes are idiopathic, sedentary lifestyle, impairments, and aging. Abnormal posture has a detrimental effect on articular and muscular structures as it leads to muscular weakness and degenerative changes. It affects the muscular tension around the neck and shoulder; as it shifts the neck forward (muscle tightness) and the shoulder moves more internally, leading the upper back scapular muscle lengthening. This study uses a flexi-curve ruler to measure postural hyper kyphosis and lateral scapula slide test(LSST) to measure scapula distance. The Blackburn protocol is often used for shoulder and scapular impairments; in this study, the protocol is used to manage postural hyper kyphosis as it targets the same muscle groups that are in an altered state. OBJECTIVE: To compare the effect of Blackburn exercise along with thoracic extension exercise versus thoracic extension exercise on postural hyper kyphosis and scapula position in young asymptomatic individuals. METHODS: A comparative study included 70 samples, age between 18 and 28, divided into 2 groups. The degree of kyphosis was measured using a flexi curve ruler (fcr), and scapula distance was measured using a lateral scapula slide test (lsst) at three positions. Intervention was given for six weeks. RESULTS: After 6 weeks of data analysis, Group A's p-value for kyphosis angle is 0.5 and lateral scapula slide test at 0 degree is 0.735, at 45 degree is 0.1992, and at 90 degree is 0.536, showing significant improvement over another group. Conclusion: Blackburn exercises, along with thoracic extension exercises, were found to be effective in reducing the angle of kyphosis in the young population. Keywords: Hyper kyphosis, Flexi curve Ruler, LSST, Blackburn protocol.

The Effects of Combined Motor Control and Isolated Extensor Strengthening versus General Exercise on Paraspinal Muscle Morphology, Composition, and Function in Patients with Chronic Low Back Pain: A Randomized Controlled Trial.

Low back pain (LBP), a globally widespread and persistent musculoskeletal disorder, benefits from exercise therapy. However, it remains unclear which type leads to greater changes in paraspinal muscle health. This study aimed to (1) compare the effects of a combined motor control and isolated lumbar extension exercise (MC+ILEX) versus a general exercise (GE) intervention on paraspinal muscle morphology, composition, and function, and (2) examine whether alterations in paraspinal muscle health were correlated with improvements in pain, function, and quality of life. Fifty participants with chronic LBP were randomly assigned to each group and underwent a 12-week supervised intervention program. Magnetic resonance imaging and ultrasound assessments were acquired at baseline, 6 and 12 weeks to examine the impact of each intervention on erector spinae (ES) and multifidus (MF) muscle size (cross-sectional area, CSA), composition, and function at L4-L5 and L5-S1. Self-reported questionnaires were also acquired to assess participant-oriented outcomes. Our findings indicated that the MC+ILEX group demonstrated greater improvements in MF and ES CSA, along with MF thickness at both levels (all p < 0.01). Both groups significantly improved in pain, function, and quality of life. This study provided preliminary results suggesting that an MC+ILEX intervention may improve paraspinal morphology while decreasing pain and disability.

Short-Term L-Citrulline Supplementation Does Not Affect Blood Pressure, Pulse Wave Reflection, or Arterial Stiffness at Rest and during Isometric Exercise in Older Males.

Hypertension and arterial stiffness are significant factors contributing to cardiovascular disease. L-citrulline, a nitric oxide precursor, has been proposed as a nutritional, non-pharmacological blood pressure-lowering intervention. This study aimed to investigate the impact of L-citrulline on central and peripheral blood pressure, pulse wave reflection, and central arterial stiffness at rest and during an isometric knee extension exercise protocol. Twelve older males received 6 g of L-citrulline or a placebo for six days using a double-blind crossover design. Blood hemodynamics parameters (i.e., aortic and brachial systolic and diastolic blood pressure, mean arterial pressure, pulse pressure, heart rate), pulse wave reflection (i.e., augmented pressure, augmentation index, forward/backward wave pressure), and arterial stiffness (i.e., carotid-femoral pulse wave velocity) were measured at baseline, post-supplementation, and during isometric exercise. No significant effects of L-citrulline supplementation were observed at rest or during exercise on blood pressure, pulse wave reflection, or arterial stiffness. Both central and peripheral blood pressure were increased during the exercise, which is consistent with isometric contractions. The results of the present study do not support any blood pressure-lowering effect of short-term L-citrulline at rest or during low-intensity isometric exercise compared to the pre-exercise values in older males.

Improving Range of Motion through Leg Extension Exercise and Static Bike Exercise for Osteoarthritis Genu

Aging is identical with decreased functional abilities, such as prolonged standing, walking, squatting, running, or other activities. These decreases in functional ability can be caused by a degenerative disease, namely osteoarthritis (OA) genu resulting in a limited motion in the knee joint caused by a decrease in range of motion. Treatments for OA Genu cases include leg extension exercise and static bike exercise to maintain and to increase the range of motion (ROM) of knee joints. This study was a Quasi Experimental study. The study lasted for five weeks from May-June. The sample of this study were 24 people. The results of the study found that the ability to movement extension and knee flexion in both groups increased. Both groups obtained p value = 0.625 for extension and p value = 0.062 for flexion. The p value of extension and flexion is p0.05. Results showed that, after the intervention in both groups, the osteoarthritis patients at Siloam Hospitals Bali had improved flexion ROM and knee extension. Based on the difference value before and after treatment, the percentage increase in range of motion extension and flexion in the static bike group was slightly higher than the leg extension exercise group. It concludes that leg extension exercise and static bike exercise are equally good in increasing ROM of osteoarthritis patients. Leg extension exercises and static bike exercise can be used as alternative exercises to improve the ability to bend and to straighten knee joints experiencing limitations or stiffness.

Synergistic Dominance Induced by Hip Extension Exercise Alters Biomechanics and Muscular Activity During Sprinting and Suggests a Potential Link to Hamstring Strain.

Iguchi, J, Hojo, T, Fujisawa, Y, Kuzuhara, K, Yanase, K, Hirono, T, Koyama, Y, Tateuchi, H, and Ichihashi, N. Synergistic dominance induced by hip extension exercise alters biomechanics and muscular activity during sprinting and suggests a potential link to hamstring strain. J Strength Cond Res 37(9): 1770-1776, 2023-Hamstring strain is likely to occur during the late swing phase or the first half of the stance phase in sprinting. During the late swing phase, the hamstrings and gluteus maximus (Gmax) contract eccentrically to decelerate the lower limb. We hypothesized that, when the Gmax becomes dysfunctional because of delayed onset muscle soreness (DOMS), the hamstring workload is increased (i.e., there is synergetic dominance), which could lead to an increased risk of strain. A total of healthy 15 male undergraduate or graduate students (age 23.1 ± 1.28 years) were recruited to perform exercises and maximal sprints. On day 1, before subjects performing DOMS-causing exercises, and on day 3, while subjects were experiencing DOMS in the Gmax, lower-limb biomechanical and muscle activity data were recorded using a motion analysis system and electromyography (EMG), respectively. Data were analyzed and compared between day 1 and day 3. Hip flexion angle on day 3 was significantly lower than that on day 1, but the opposite was true for the knee flexion angle (P < 0.05). Vastus medialis (VM), biceps femoris (BF), and Gmax muscle activities on day 3 were significantly higher than those on day 1 (P < 0.05). Peak propulsive forces on day 3 were significantly higher than those on day 1 (P < 0.05). Kinematic changes such as decreased hip flexion angle and EMG changes such as increased BF EMG activity on day 3 to compensate for the loss of function of the Gmax may potentially increase the risk of hamstring strain.

The Effect of the Pyramid Exercise Method on the Maximum Strength of the Wrestler’s Arm Muscles

Study purpose. The purpose of this study was to determine the effect of reverse grip barbell curls and barbell triceps extension exercises on increasing the maximum strength of the arm muscles of wrestling athletes. Materials and methods. This type of research is quasi-experimental. The population in the study was 24 wrestling athletes. Sampling was carried out using purposive sampling techniques, namely 10 male wrestling athletes. The research instrument was carried out by lifting a load that was only able to be lifted 1 time or expressed ability (maximum strength) using a barbell. The data analysis technique used is hypothesis testing using the t-test formula. Results. The results of this study showed that the exercises of reverse grip barbell curls and barbell triceps extension have an effect on the increase in the maximum strength of the arm muscles of wrestling athletes; from the initial test and the final test results, there was an increase with a difference of 1.04, namely from an average score of 29.9 kg in the pre-test to 32.3 kg in the post-test. Conclusions. The conclusion in this study is that there is a significant influence of the reverse grip form of barbell curls and barbell triceps extension on the increase in maximum strength of the arm muscles in wrestling athletes.

Effects of acute resistance exercise on exhaled nitric oxide levels in non-asthmatic male

Fractional nitric oxide (FeNO) is an index of eosinophilic airway inflammation. However, the effect of acute resistance exercise on FeNO is not completely known, in non-asthmatics. In this study, we aimed to assess the effects of acute resistance exercise on FeNO levels in non-asthmatics. Ten participants completed both exercise and control sessions. The resistance exercise routine consisted of three sets of 10 repetitions, each at 75 % of the one-repetition maximum, including vertical chest press, lateral pull-down, leg press, leg extension, and abdominal exercises. Additionally, FeNO levels and respiratory impedance were measured, and blood samples were collected from each participant at baseline, immediately after exercise (post), and 30 min after exercise (post 30). At baseline, post, and post 30, the FeNO levels did not significantly differ between the exercise and control sessions (17.1 ± 4.7 vs. 18.5 ± 3.8 vs. 16.9 ± 3.8 ppb, respectively) and exercise sessions (16.6 ± 3.4 vs. 19.3 ± 7.6 vs. 18.3 ± 5.6 ppb, respectively). Therefore, acute resistance exercise lasting approximately 30 min did not exert an impact on FeNO levels.

Knee Extension Exercise Effects on Physiological and Psychophysical Performance: Normal Weight Versus Obese Office Workers.

Knee extension exercise is useful and practical for obese and overweight people as this form of exercise is effective in minimizing body weight loading on joints and improving the body's physiological function. This study aimed to compare the physiological and psychophysical parameters of office workers while computer-based working in an active workstation equipped with an active footrest (AFR) prototype with a mechanism for performing knee extension exercises in a sitting position, and also to compare the physiological and psychophysical parameters among normal-weight and obese office workers. In this quasi-experimental study, the physiological parameters of heart rate (HR) and energy expenditure (EE) (measured with the Fitbit Charge HR smartwatch) were measured in two cross-over random sessions for 32 office workers (16 normal-weight and 16 obese) aged 28 to 50 years (M = 42.72, standard deviation [SD] = 4.37) while performing office tasks in sitting and active workstations (equipped with AFR). Perceived physical exertion, comfort, fatigue, and liking were also measured by rating the participants. Short-term activity of the participants with AFR performing computer tasks significantly improved physiological and psychophysical parameters compared with the participants in sitting workstations. However, there was no significant difference in the effect of AFR on physiological and psychophysical parameters between normal-weight and obese participants. Given the significant increase in EE and HR resulting from exercise with AFR compared with the conventional workstation, the use of AFR can help office workers achieve the minimum standard of physical activity at their workplace.

Effect of Mckenzie lumbar extension exercise with TENS on lumbar radiculopathy

Effect of Mckenzie lumbar extension exercise with TENS on lumbar radiculopathy

Adaptive Sliding Mode Feedback Control Algorithm for a Nonlinear Knee Extension Model

Functional electrical stimulation (FES) has been widely used to treat spinal cord injury (SCI) patients. Many research studies employ a closed-loop FES system to monitor the stimulated muscle response and provide a precise amount of charge to the muscle. However, most closed-loop FES devices perform poorly and sometimes fail when muscle nonlinearity effects such as fatigue, time delay response, stiffness, spasticity, and subject change happen. The poor performance of the closed-loop FES device is mainly due to discrepancies in the feedback control algorithms. Most of the existing feedback control algorithms were not designed to adapt to new changes in patients with different nonlinearity effects, resulting in early muscle fatigue. Therefore, this research proposes an adaptive sliding mode (SM) feedback control algorithm that could adapt and fine-tune internal control settings in real-time according to the current subject’s nonlinear and time-varying muscle response during the rehabilitation (knee extension) exercise. The adaptive SM feedback controller consists mainly of system identification, direct torque control, and tunable feedback control settings. Employing the system identification unit in the feedback control algorithm enables real-time self-tuning and adjusting of the SM internal control settings according to the current patient’s condition. Initially, the patient’s knee trajectory response was identified by extracting meaningful information, which included time delay, rise time, overshoot, and steady-state error. The extracted information was used to fine-tune and update the internal SM control settings. Finally, the performance of the proposed adaptive SM feedback control algorithm in terms of system response time, stability, and rehabilitation time was analysed using a nonlinear knee model. The findings from the simulation results indicate that the adaptive SM feedback controller demonstrated the best control performance in accurately tracking the desired knee angle movement by having faster response times, smaller overshoots, and lower steady-state errors when compared with the conventional SM across four reference angle settings (20°, 30°, 40°, and 76°). The adaptive feedback SM controller was also observed to compensate for muscle nonlinearities, including fatigue, stiffness, spasticity, time delay, and other disturbances.

Early Rehabilitation with Exergame Which Muscle Groups are Addressed by Bedside-Based Knee Exercises?

Background. Knee exercises are generally recommended following knee-related operations. Nevertheless, compliance in performing self-administered exercises is varying. The use of exergames may alter patient compliance. These computer games encourage the user to exercise. Exergames are not yet used much in orthopedic rehabilitation. The aim of this study was to analyze the influence of different seating positions in electromyography while performing knee exercises with the exergame GenuSport.Material and methods. 72 healthy women and men were tested in 6 seating positions using an application-based knee-training device (KT). Positions were 1. user seated 90 upright with straight leg on KT, 2. 90 upright with leg exercising in external rotation on KT, 3. 90 upright with leg exercising in internal rotation on KT, 4. 90 upright with straight leg on 30mm elevated KT, 5. 45 upright with straight leg on KT and 6. 45 upright with straight leg on 30mm elevated KT. Electromyogram was recorded for biceps femoris, rectus femoris, semitendinosus, vastus medialis, adductor magnus and vastus lateralis.Results. No significant difference was shown in position 2, 3 or 4 compared to position 1. In position 5 and 6, EMG reported significantly higher values compared to positions 1 to 4 (ischiocrural: 130% and quadriceps: 90%). The quadriceps was activated significantly less in position 6 compared to 5.Conclusion. 1. Bedside-based knee extension exercises are most effective in a seated position of 45 trunk inclination. 2. A slightly more bent knee (KT elevation of 30mm) leads to a higher activation of the ischiocrural muscles.

Effects of the Addition of Hands-on Procedures to McKenzie Exercises on Pain, Functional Disability and Back Mobility in Patients with Low Back Pain: A Randomised Clinical Trial.

Low back pain (LBP) is a common musculoskeletal disorder that affects people of all ages. This study investigates the effects of the addition of hands-on procedures to McKenzie exercises on patients with LBP and derangement syndrome. Forty-eight female patients were randomly assigned to either the experimental group or control group. All the patients in both groups underwent McKenzie exercises, transcutaneous electrical nerve stimulation (TENS) and education for 35 min/session-45 min/ session, with three sessions/week for 2 weeks. Hands-on procedures were added to the McKenzie extension exercises only for the patients in the experimental group. A visual analogue scale (VAS), the Oswestry disability index (ODI), back range of motion (BROM) and body diagrams were used to measure pain, functional disability, BROM and the centralisation of symptoms, respectively. The mean values of VAS, ODI and BROM significantly improved after the interventions in both groups (P < 0.05), whereas the results of repeated measures ANOVA and Mann-Whitney U tests showed statistically non-significant differences between the two groups (P > 0.05). The addition of hands-on procedures to McKenzie exercises, TENS and education significantly alleviated back pain and functional disability and improved the back mobility and centralisation of symptoms in patients with LBP and derangement syndrome; however, these measures did not result in any significant additional benefits for such patients.

Comparison of McKenzie Extension v/s William’s Flexion Exercises in Mechanical Back Pain among Medical Students

Background This study compared the effects of McKenzie's Extension exercises versus William’s Flexion exercises on mechanical back pain in medical students aged 18-25. The high incidence of low back pain among medical students is attributed to stress, long hours of studying and working in a clinical setting, poor posture, and physical inactivity. Methods In a six-month randomized controlled trial, 30 participants were assigned to Group A (McKenzie Extension exercises) and Group B (William’s Flexion exercises). Pain levels were measured using the Numeric Pain Rating Scale before and after the study. Paired sample t-tests and independent t-tests were used for within-group and between-group analysis, respectively. Results The study demonstrated that both exercise groups experienced a reduction in pain levels after 3 weeks of home exercise. However, the McKenzie Extension group exhibited a more significant (p&lt;0.05) decrease than William’s Flexion group. Conclusion McKenzie’s Extension exercises were deemed more effective than William’s Flexion exercises in reducing mechanical back pain among medical students. Keywords Activities of Daily Living, Exercises, Low Back Pain, Medical students.

Musculoskeletal Model Capable of Reproducing Lumbar Extension Motion Strategy Based on the Equilibrium Point Hypothesis

We considered the change in joint stiffness as a motion strategy in human lumbar extension movement. We developed a musculoskeletal model that can reproduce this motion strategy and attempted to clarify the individual characteristics and differences in motion strategy. This model reproduces changes in lumbar joint stiffness during movement by appropriately adjusting parameters such that they represent the motion strategy. Using this model, we identified parameters in lumbar extension exercises for six participants with differences in lumbar joint stiffness and examined changes in lumbar joint stiffness and motion strategies. The results showed that participants with similar changes in joint stiffness had commonalities in their motion strategies.