Plantar Flexion Peak Torque Research Articles

Immediate effect of kinesiology taping on muscle strength, static balance and proprioception after eccentric muscle fatigue on ankle: a randomized cross-over trial

BackgroundKinesiology Taping(KT) is commonly used as a physical therapy to prevent exercise-induced fatigue. This study aims to evaluate the immediate effects of KT on muscle strength, static balance, and proprioception after eccentric muscle fatigue on ankle.MethodsTwenty healthy male university students were recruited. The experimental protocol was structured into four sessions, each separated by a one-week washout period to prevent carryover effects. Participants were randomly allocated to one of four intervention conditions in each session, ensuring no participant received the same intervention twice. These conditions were: no taping(NT),sham taping(ST),athletic taping(AT),and kinesiology taping(KT).Taping was applied immediately following an eccentric muscle fatigue protocol targeting the ankle, and assessments were conducted in the order of proprioception, muscle strength and static balance. Isometric muscle strength and proprioception were evaluated using the Biodex isokinetic system. Static balance was measured using the TecnoBody balance platform.ResultsKT had a significantly higher plantarflexion/dorsiflexion peak torque, dorsiflexion average peak torque, and plantarflexion/dorsiflexion average power at 60°/s compared with NT and ST in terms of isometric muscle strength (p < 0.05).Furthermore, the plantarflexion peak torque of KT was significantly greater than AT at 60°/s[p = 0.005,95% confidence interval(CI) = 3.39 to 18.20] and 180°/s[p = 0.006,95%CI(2.62,21.98)]. In terms of proprioception, KT showed a lower absolute error in 25° plantarflexion and 10° dorsiflexion compared to NT, ST and AT. For static balance with eyes-open and eyes-closed conditions, AT and KT had a lower total sway area than NT and ST (p < 0.05). Additionally, a significant difference in total sway length with eyes-open condition was observed between AT and KT[p < 0.001,95%CI(-431.81,-168.25)];total sway area and the center of pressure(COP) velocity in the mediolateral(ML) and anteroposterior(AP) directions with eyes-closed condition were significantly lower in AT compared to KT.ConclusionThis study suggests that KT is more effective than other taping conditions in improving muscle strength and proprioception after eccentric muscle fatigue on ankle. However, AT is more helpful in increasing static postural control ability after ankle muscle fatigue than KT.Trial registrationThis study was registered with www.chictr.org.cn (registration number: ChiCTR2300068278) on 13/2/2023.

Does spastic myopathy determine active movement and ambulation speed in chronic spastic paresis?-A cross-sectional study on plantar flexors.

Functional correlates of spastic myopathy, the muscle disorder of spastic paresis, are unknown. To explore reciprocal relationships between clinical and structural parameters of plantar flexors with i) ambulation speed, ii) dorsiflexion and plantarflexion torques in chronic hemiparesis. Cross-sectional trial in chronic stroke-induced hemiparesis (>6 months). Plantar flexors were quantified through i) the Five Step Assessment: maximal extensibility (XV1), active range of dorsiflexion (XA); ii) ultrasonography: fascicle length (Lf) and thickness (Th) of medial gastrocnemius (GAS) and soleus (SOL), knee extended in an isokinetic ergometer, ankle at 80% XV1-GAS. Maximal isometric torques in plantar flexion (PF) and dorsiflexion (DF) and maximal barefoot 10-meter ambulation speed were collected. Relationships between structural, biomechanical, clinical and functional parameters were explored using non-parametric testing (Spearman). Twenty-one subjects (age 58.0±8.4, mean±SD, time since lesion 7.8±5.7 years) were recruited, with the following characteristics: ambulation speed, 0.77±0.37m/sec; XV1-SOL 92.7±10.3°; XV1-GAS 91.3±9.6°; XA-SOL 86.9±10.0°; XA-GAS 7676±14.2°; LfGAS, 58.2±18.3mm; ThGAS, 17.1±3.6 mm; LfSOL, 36.0±9.6 mm; ThSOL, 13.8±3.3mm; PF peak-torque 46.5±34.1Nm, DF peak-torque, 20.1±19.1Nm. XA-SOL and XA-GAS strongly correlated with XV1-SOL and XV1-GAS respectively (ρ = 0.74, p = 4E-04; resp ρ = 0.60, p = 0.0052). Ambulation speed moderately correlated with LfGAS (ρ = 0.51, p = 0.054), ThGAS (ρ = 0.58, p = 0.02) and LfSOL (ρ = 0.63, p = 0.009). DF and PF peak-torques both correlated with LfGAS (ρ = 0.53, p = 0.04) a; resp. ρ = 0.71, p = 0.0015). In chronic hemiparesis, active dorsiflexion is mostly determined by plantar flexor extensibility. Plantar flexor fascicle shortening is associated with reduced ambulation speed and ankle torques. Attempts to restore plantar flexor extensibility might be important objectives for gait rehabilitation in chronic hemiparesis.

The Effects of a 12-Week-Long Sand Exercise Training Program on Neuromechanical and Functional Parameters in Type II Diabetic Patients with Neuropathy.

Studies have proven the effectiveness of different weight-bearing exercise interventions for diabetic patients with neuropathy; however, several adverse effects were reported using solid surfaces. Thus, in the present study, we investigated the effects of a novel sand exercise training intervention on biomechanical and functional parameters in seven diabetic patients (age = 62.7 ± 9.7 years) with neuropathy. Patients underwent a 12-week sand exercise training program, using strengthening, stretching, balance, and gait exercises. They were tested for ankle plantar- and dorsiflexion peak torque, active range of motion (ROM), timed up and go (TUG), and bilateral static balance. EMG activity of tibialis anterior (TA), gastrocnemius medialis (GM), and lateralis (GL) muscles were measured during unilateral isometric contraction in plantar- and dorsiflexion. In the intervention period, plantarflexion peak torque improved significantly (p = 0.033), while dorsiflexion torque remained unchanged. Plantar- and dorsiflexion ROM increased (p = 0.032) and (p = 0.021), respectively. EMG activity of GM (p = 0.005) and GL (p = 0.002) measured during dorsiflexion and postural sway in the balance test, as well as time to complete the TUG test, decreased significantly (p = 0.021) and (p = 0.002), respectively. No adverse effect was reported during the intervention period. We concluded that sand exercise training can be a safe and effective method to improve plantarflexion strength, ankle flexibility, and balance, which is reflected in better gait function in patients with diabetic peripheral neuropathy (DPN).

Muscle strength and spatiotemporal gait parameters in people with Parkinson´s disease. A pilot study.

Muscle weakness in persons with Parkinson disease (PD) has been frequently recognized as a nonspecific symptom. In other neurological conditions, lower limb weakness, specifically quadriceps weakness, is the factor that causes greater gait disability. Little research has evaluated the relationship between lower limb muscle strength, using objective tools, in PD persons and gait performance. The aim of this study was to analyze the correlation between lower limb muscle strength, using an isokinetic dynamometer, and the spatiotemporal gait parameters in PD, compared with age- and sex- matched healthy controls. The study was conducted with 7 persons with PD -Hoehn and Yahr (HY) between II-III- and 7 healthy controls. Isokinetic knee and ankle tests at 60 and 120°/s and the 10-meter walking test at comfortable and fast walking speed, were performed on all recruited subjects. Significant differences in lower limb strength-related measures and gait parameters were observed between persons with PD and controls. Gait parameters showed excellent correlations (rho = 0.7) for both lower limb: ankle plantar flexion work/body wearing at 180°/s with number of steps (indirect) and stride (direct) at both speeds, and between the ankle plantar flexion peak torque/ body wearing at 180°/s with number of steps (indirect) and stride (direct) at maximum speed; and between knee extension work/body wearing at 60°/s) with stride (direct) at self-selected speed. Persons with PD (HY II-III stages) lower limb muscle strength correlates excellently with gait pattern, showing lower isokinetic strength than healthy subjects of the same age and sex. This protocol showed safety to be performed in a larger sample.

The effects of using a combination of static stretching and aerobic exercise on muscle tendon unit stiffness and strength in ankle plantar-flexor muscles

ABSTRACT The purpose of the present study was to investigate the effects of using a combination of static stretching and aerobic exercise on muscle tendon unit stiffness and muscle strength in the ankle plantar-flexor muscles. Fifteen healthy males (23.3 ± 2.7 years, 170.3 ± 6.5 cm, 64.9 ± 8.7 kg) received three different interventions, in random order. Intervention 1 received 10 min of aerobic exercise after five cycles of one minute of static stretching. Intervention 2 received 10 min of aerobic exercise before the static stretching. Intervention 3 received 5 min of aerobic exercise both before and after the static stretching. The range of motion of ankle dorsiflexion, stretch tolerance, muscle tendon unit stiffness, peak torque of ankle plantarflexion, and the amplitude of electromyography were measured. In all interventions, the range of motion and stretch tolerance significantly increased (p < 0.05), but muscle tendon unit stiffness decreased significantly for all interventions (p < 0.05). Peak torque of ankle plantar flexion and amplitude of electromyography significantly increased for Interventions 1 and 3 (p < 0.05), while these significantly decreased for Intervention 2 (p < 0.05). These data indicated that range of motion and stretch tolerance were increased, but muscle tendon unit stiffness was decreased regardless of the order of static stretching and aerobic exercise. Aerobic exercise after static stretching increased the peak torque and amplitude of electromyography.

Influence of Aerobic Exercise After Static Stretching on Flexibility and Strength in Plantar Flexor Muscles.

Aerobic exercise could improve stretch-induced strength deficits. However, mechanisms of the improvement were unclear. The purpose of the study was to examine the effects of aerobic exercise after static stretching (SS) on flexibility and isometric strength in ankle plantar-flexor muscles. Fifteen healthy males received two interventions after SS of their ankle plantar-flexor muscles for 5 min. One was aerobic exercise for 10-min on a cycling ergometer, and the other was a 10-min rest as a control. Range of motion (ROM) of ankle dorsiflexion, passive torque at terminal ROM, muscle-tendon unit (MTU) stiffness, muscle tendon junction displacement, peak torque of ankle plantarflexion, and the amplitude of electromyography (EMG) were measured. Immediately after the SS, in both interventions, ROM, passive torque, and muscle tendon junction displacement increased significantly (p < 0.05), while MTU stiffness, peak torque, and the amplitude of EMG were significantly decreased (p < 0.05). After 10-min on a cycling ergometer, the decreased peak torque and amplitude of EMG indicated higher values than those before SS (p < 0.05), while MTU stiffness was no change. In conclusion, SS increased ROM because of the decreased MTU stiffness as well as increased tolerance for stretching. Aerobic exercise could increase the muscle strength and amplitude of EMG which decreased after static stretching.

Altered Strength Profile in Achilles Tendinopathy: A Systematic Review and Meta-Analysis.

Persistent strength deficits secondary to Achilles tendinopathy (AT) have been postulated to account for difficulty engaging in tendon-loading movements, such as running and jumping, and may contribute to the increased risk of recurrence. To date, little consensus exists on the presence of strength deficits in AT. Consequently, researchers are uncertain about the appropriate methods of assessment that may inform rehabilitation in clinical practice. To evaluate and synthesize the literature investigating plantar-flexion (PF) strength in individuals with AT. Two independent reviewers searched 9 electronic databases using an agreed-upon set of key words. Data were extracted from studies comparing strength measures (maximal, reactive, and explosive strength) between individuals with AT and healthy control participants or between the injured and uninjured sides of people with AT. The Critical Appraisal Skills Programme Case-Control Study Checklist was used to assess the risk of bias for the included studies. A total of 19 studies were eligible. Pooled meta-analyses for isokinetic dynamometry demonstrated reductions in maximal strength (concentric PF peak torque [PT] slow [Hedges g = 0.52, 44% deficit], concentric PF PT fast [Hedges g = 0.61, 38% deficit], and eccentric PF PT slow [Hedges g = 0.26, 18% deficit]). Reactive strength, particularly during hopping, was also reduced (Hedges g range = 0.32-2.61, 16%-35% deficit). For explosive strength, reductions in the rate of force development (Hedges g range = 0.31-1.73, 10%-21% deficit) were observed, whereas the findings for ground reaction force varied but were not consistently altered. Individuals with AT demonstrated strength deficits compared with the uninjured side or with asymptomatic control participants. Deficits were reported across the strength spectrum for maximal, reactive, and explosive strength. Clinicians and researchers may need to adapt their assessment of Achilles tendon function, which may ultimately help to optimize rehabilitation outcomes.

Neuromuscular Factors Contributing to Reductions in Muscle Force After Repeated, High-Intensity Muscular Efforts

Multiple neuromuscular processes contribute to the loss of force production following repeated, high-intensity muscular efforts; however, the relative contribution of each process is unclear. In Experiment 1, 16 resistance trained men performed six sets of unilateral isometric plantar flexor contractions of the right leg (3 s contraction/2 s rest; 85% maximal voluntary contraction torque; 90-s inter-set rest) until failure with and without caffeine ingestion (3 mg kg-1) on two separate days. Corticospinal excitability and cortical silent period (cSP) were assessed before and immediately, 10 and 20 min after the exercise. In Experiment 2, electrically evoked tetanic force and persistent inward current (PIC)-mediated facilitation of the motor neuron pool (estimated using neuromuscular electrical stimulation with tendon vibration) were assessed before and after the same exercise intervention in 17 resistance trained men. Results showed decreases in peak plantar flexion torque (Experiment 1: -12.2%, Experiment 2: -16.9%), electrically evoked torque (20 Hz -15.3%, 80 Hz -15.3%, variable-frequency train -17.9%), and cSP (-3.8%; i.e., reduced inhibition) post-exercise which did not recover by 20 min. Electromyographic activity (EMG; -6%), corticospinal excitability (-9%), and PIC facilitation (-24.8%) were also reduced post-exercise but recovered by 10 min. Caffeine ingestion increased torque and EMG but did not notably affect corticospinal excitability, PIC amplification, or electrically evoked torque. The data indicate that a decrease in muscle function largely underpins the loss of force after repeated, high-intensity muscular efforts, but that the loss is exacerbated immediately after the exercise by simultaneous decreases in corticospinal excitability and PIC amplitudes at the motor neurons.

Isokinetic functional outcomes of open versus percutaneous repair following Achilles tendon tears

Category: Sports Introduction/Purpose: Rupture of the Achilles Tendon (AT) is frequent in young recreational athletes. Conservative management, open surgery and percutaneous/minimally invasive approaches are all advocated, and conflicting data are available. This study compared functional and anthropometric outcomes of patients who underwent open or percutaneous repair. Methods: A retrospective comparative study, in which 38 patients underwent open and percutaneous techniques to manage AT ruptures. For functional assessment, the calf circumference of both injured and uninjured legs was evaluated. Isokinetic testing included total plantar flexion work, peak plantar flexion torque, total dorsiflexion work peak and dorsiflexion torque. The Achilles Tendon Rupture Score (ATRS) and the America Orthopedic Foot and Ankle Score (AOFAS) were evaluated at a final minimum follow-up of 12 months. Results: No major complications were observed. The average time to return to sport was 9 months. AOFAS and ATRS values did not differ statistically between groups. Isokinetic variables and circumference were similar in the operated and non-operated limb in both groups, and did not differ either when comparing open and percutaneous repair. Conclusion: Open and percutaneous repair of a torn Achilles tendon produced similar functional outcomes.

Static stretching program decrease the eccentric peak torque without changing the functional perfomance in healthy adults - A randomized controlled trial

To describe the Return to competition after Achilles Tendon rupture (ATR) in an elite soccer player.Case report.Return to sport (RTS) of a professional soccer player who suffered an ATR during a match. The RTS phase started 15 weeks after surgery and specific on-field activities were gradually introduced. Criteria used to monitor the transition through the different phases were strength and endurance of the calf muscle and ability to sustain specific on-field training loads (TL) monitored with Global Positioning System and heart-rate system. TLs were weekly compared to pre-injury values to evaluate recovery and to prescribe future sessions.A 39-year-old (height 178 cm, weight 75 kg) elite soccer defender player, playing in Italian Serie-A league.Days of absence were lower compared to a cohort presented in UEFA study (119 versus 161 ± 65 days, respectively). External-TL and Internal-TL were organized to gradually increase during RTS and resulted in higher values prior to return to competition compared to pre-injury values. Concentric plantar flexion peak torque increased till 9th months after surgery.Monitoring of the field activities allowed comparison with pre-injury values and provided a useful and functional criteria to pass return to team activity and competition.

Effect of Compression Garments on Physiological Responses After Uphill Running.

Limited practical recommendations related to wearing compression garments for athletes can be drawn from the literature at the present time. We aimed to identify the effects of compression garments on physiological and perceptual measures of performance and recovery after uphill running with different pressure and distributions of applied compression. In a random, double blinded study, 10 trained male runners undertook three 8 km treadmill runs at a 6% elevation rate, with the intensity of 75% VO2max while wearing low, medium grade compression garments and high reverse grade compression. In all the trials, compression garments were worn during 4 hours post run. Creatine kinase, measurements of muscle soreness, ankle strength of plantar/dorsal flexors and mean performance time were then measured. The best mean performance time was observed in the medium grade compression garments with the time difference being: medium grade compression garments vs. high reverse grade compression garments. A positive trend in increasing peak torque of plantar flexion (60º·s-1, 120º·s-1) was found in the medium grade compression garments: a difference between 24 and 48 hours post run. The highest pain tolerance shift in the gastrocnemius muscle was the medium grade compression garments, 24 hour post run, with the shift being +11.37% for the lateral head and 6.63% for the medial head. In conclusion, a beneficial trend in the promotion of running performance and decreasing muscle soreness within 24 hour post exercise was apparent in medium grade compression garments.

Isokinetic functional outcomes of open versus percutaneous repair following Achilles tendon tears

BackgroundRupture of the Achilles tendon (AT) is frequent in young recreational athletes. Conservative management, open surgery and percutaneous/minimally invasive approaches are all advocated, and conflicting data are available. This study compared functional and anthropometric outcomes of patients who underwent open or percutaneous repair. MethodsA retrospective comparative study, in which 38 patients underwent open and percutaneous techniques to manage AT ruptures. For functional assessment, the calf circumference of both injured and uninjured legs was evaluated. Isokinetic testing included total plantar flexion work, peak plantar flexion torque, total dorsiflexion work peak and dorsiflexion torque. The Achilles Tendon Rupture Score (ATRS) and the American Orthopedic Foot and Ankle Score (AOFAS) were evaluated at a final minimum follow-up of 12months. ResultsNo major complications were observed. The average time to return to sport was 9months. AOFAS and ATRS values did not differ statistically between groups. Isokinetic variables and circumference were similar in the operated and non-operated limb in both groups, and did not differ either when comparing open and percutaneous repair. ConclusionsOpen and percutaneous repair of a torn Achilles tendon produced similar functional outcomes.

The effects of motor adaptation on ankle isokinetic assessments in older drivers

OBJECTIVES:This study sought to analyze the extent of motor adaptation in ankle plantar flexors and dorsiflexors among older drivers during clinical isokinetic testing.METHODS:One hundred older adults (70.4±5.7 years) participated in two bilateral ankle plantar flexor and dorsiflexor isokinetic assessments at 30°/sec. Peak torque (PTQ), PTQ adjusted for body weight (PTQ/BW), and total work (TW) were analyzed.RESULTS:On the dominant side, PTQ/BW and TW were significantly greater for the second plantar flexion test than were those for the first such test (p<0.001), whereas PTQ, PTQ/BW, and TW (p<0.001) were significantly greater for the second dorsiflexion test than were those for the first such test. On the non-dominant side, plantar flexion PTQ and TW were significantly lower for the second test than were those for the first test (p<0.001).CONCLUSION:Older drivers demonstrated better performance with the dominant limb on the second test. The low variability in test execution showed the existence of a motor adaptation effect for the tested movements, despite the short recovery period between the assessments.

Management of chronic tendo achilles tear by various surgical techniques

Introduction: The common type of sports injury is Achilles tendon rupture and the most common cause of injury is sudden plantar flexion or dorsiflexion of the ankle. About 10-25% of acute ruptures is not diagnosed initially. Patients with Tendo Achilles rupture mostly report with functional deficits. Many procedures have been described in the literature for chronic Achilles tendon rupture reconstruction. All these surgical procedures have been shown to have satisfactory clinical results, although ankle plantar flexion strength and peak torque deficits persisted. Material and Method: A total of 22 cases of chronic Tendo Achillies rupture were included in the study over a period of 2 years from July 2015 to July 2017 at Dr. D. Y. Patil Medical College and Hospital, Pimpri, Pune. Result: Among the three operative procedures, the functional recovery was good in Gastrocnemius-Soleus fascia turn down graft procedure as assessed by the clinical examination of the plantar flexion and Karlsson and Petersson scoring.

Chronic Stretching During 2 Weeks of Immobilization Decreases Loss of Girth, Peak Torque, and Dorsiflexion Range of Motion.

Chronic plantarflexor (PF) stretching during ankle immobilization helps preserve calf girth, plantarflexion peak torque, and ankle dorsiflexion (DF) motion. Immobilization can lead to decreases in muscle peak torque, muscle size, and joint range of motion (ROM). Recurrent static stretching during a period of immobilization may reduce the extent of these losses. To investigate the effects of chronic static stretching on PF peak torque, calf girth, and DF ROM after 2 weeks of ankle immobilization. Randomized controlled clinical trial. Athletic training facility. A total of 36 healthy college-aged (19.81 [2.48]) females. Subjects were randomly assigned to one of 3 groups: control group, immobilized group (IM), and immobilized plus stretching (IM+S) group. Each group participated in a familiarization period, a pretest, and, 2 weeks later, a posttest. The IM group and IM+S group wore the Aircast Foam Pneumatic Walker for 2 weeks on the left leg. During this time, the IM+S group participated in a stretching program, which consisted of two 10-minute stretching procedures each day for the 14 days. One-way analysis of variance was used to determine differences in the change of ankle girth, PF peak torque, and DF ROM between groups with an α level of <.05. A significant difference was noted between groups in girth (F2,31 = 5.64, P = .01), DF ROM (F2,31 = 26.13, P < .001), and PF peak torque (F2,31 = 7.74, P = .002). Post hoc testing also showed a significance difference between change in calf girth of the control group compared with the IM group (P = .01) and a significant difference in change of peak torque in the IM+S group and the IM group (P = .001). Also, a significant difference was shown in DF ROM between the control group and IM+S group (P = .01), the control group and the IM group (P < .001), and the IM+S group and the IM group (P < .001). Chronic static stretching during 2 weeks of immobilization may decrease the loss of calf girth, ankle PF peak torque, and ankle DF ROM.

Effects of shoe collar height on sagittal ankle mechanics during weight-bearing dorsiflexion movement and lay-up jump

This study aims to investigate the effects of wearing high-top and low-top basketball shoes on the ankle joint kinematics, kinetics and performance in the sagittal plane during weight-bearing dorsiflexion (WB-DF) movement and lay-up jump. Twelve subjects performed WB-DF movement and lay-up jumps (LU) in two shoe conditions. Wearing HS can significantly reduce ankle joint excursion in WB-DF. No significant differences were found in jumping height and kinematics between the two shoes. In LU, peak plantarflexion torque and power were significantly lower in HS. The high-top shoes adopted in this study did not restrict the ankle dorsiflexion performance during actual jumping. But it is suggested that the greater power in LS during LU may have a greater potential in the actual game with different conditions, such as the distance of the shot and opposition. Thus, high shoe collar height would be applied to practical with the caution of affecting the partial kinetic characteristics of the ankle joint in the sagittal plane.

Return to competition after an Achilles tendon rupture using both on and off the field load monitoring as guidance: A case report of a top-level soccer player

ObjectivesTo describe the Return to competition after Achilles Tendon rupture (ATR) in an elite soccer player. DesignCase report. SettingReturn to sport (RTS) of a professional soccer player who suffered an ATR during a match. The RTS phase started 15 weeks after surgery and specific on-field activities were gradually introduced. Criteria used to monitor the transition through the different phases were strength and endurance of the calf muscle and ability to sustain specific on-field training loads (TL) monitored with Global Positioning System and heart-rate system. TLs were weekly compared to pre-injury values to evaluate recovery and to prescribe future sessions. ParticipantA 39-year-old (height 178 cm, weight 75 kg) elite soccer defender player, playing in Italian Serie-A league. ResultsDays of absence were lower compared to a cohort presented in UEFA study (119 versus 161 ± 65 days, respectively). External-TL and Internal-TL were organized to gradually increase during RTS and resulted in higher values prior to return to competition compared to pre-injury values. Concentric plantar flexion peak torque increased till 9th months after surgery. ConclusionsMonitoring of the field activities allowed comparison with pre-injury values and provided a useful and functional criteria to pass return to team activity and competition.

The application of contralateral acupuncture for rehabilitation after acute closed achilles tendon rupture

To observe the differences of affected-side ankle plantar flexors function and clinical efficacy between contralateral acupuncture combined with rehabilitation training and rehabilitation training alone for patients with acute closed achilles tendon rupture. Seventy-four patients with acute closed achilles tendon rupture were randomly assigned to an observation group and a control group, 37 cases in each group. Patients in the both groups were treated with routine rehabilitation training after the operation for 12 weeks; besides, patients in the observation group were treated with contralateral acupuncture at Zusanli (ST 36), Yanglingquan (GB 34), Chengshan (BL 57), Taixi (KI 3) before rehabilitation training in the first 6 weeks. The treatment were given once a day, 5 times as 1 course with 2 d at the interval. The Biodex System 4 multi-joint dynamometers system was applied to test and compare affected-side plantar flexion peak torque (PFPT), peak torque/body weight (PT/BW) and total work (TW) after 6 weeks, 8 weeks and 12 weeks. The efficacy evaluation was conducted after 6 weeks and 12 weeks, and the follow-up visit was conducted 12 weeks after end of treatment. The PFPT, PT/BW, TW in the observation group were significantly superior to those in the control group after 8 weeks and 12 weeks of treatment (all P<0.05); compared with those after 6 weeks, the PFPT, PT/BW, TW were significantly increased after 8 weeks of treatment (all P<0.05); compared with those after 6 weeks and 8 weeks, the PFPT, PT/BW, TW were significantly increased after 12 weeks of treatment (all P<0.05). After 12 weeks of treatment and at follow-up visit, the clinical excellent and effective rates in the observation group were higher than those in the control group[89.2% (33/37) vs 70.3% (26/37), 94.6% (35/37) vs 75.7% (28/37), both P<0.05]. During the postoperative rehabilitation of acute closed achilles tendon rupture, the contralateral acupuncture combined with rehabilitation training could improve ankle plantar flexors function and clinical efficacy better than rehabilitation training only.

Agonist muscle adaptation accompanied by antagonist muscle atrophy in the hindlimb of mice following stretch-shortening contraction training

BackgroundThe vast majority of dynamometer-based animal models for investigation of the response to chronic muscle contraction exposure has been limited to analysis of isometric, lengthening, or shortening contractions in isolation. An exception to this has been the utilization of a rat model to study stretch-shortening contractions (SSCs), a sequence of consecutive isometric, lengthening, and shortening contractions common during daily activity and resistance-type exercise. However, the availability of diverse genetic strains of rats is limited. Therefore, the purpose of the present study was to develop a dynamometer-based SSC training protocol to induce increased muscle mass and performance in plantarflexor muscles of mice.MethodsYoung (3 months old) C57BL/6 mice were subjected to 1 month of plantarflexion SSC training. Hindlimb muscles were analyzed for muscle mass, quantitative morphology, myogenesis/myopathy relevant gene expression, and fiber type distribution.ResultsThe main aim of the research was achieved when training induced a 2-fold increase in plantarflexion peak torque output and a 19% increase in muscle mass for the agonist plantaris (PLT) muscle. In establishing this model, several outcomes emerged which raised the value of the model past that of being a mere recapitulation of the rat model. An increase in the number of muscle fibers per transverse muscle section accounted for the PLT muscle mass gain while the antagonist tibialis anterior (TA) muscle atrophied by 30% with preferential atrophy of type IIb and IIx fibers. These alterations were accompanied by distinct gene expression profiles.ConclusionsThe findings confirm the development of a stretch-shortening contraction training model for the PLT muscle of mice and demonstrate that increased cross-sectional fiber number can occur following high-intensity SSC training. Furthermore, the TA muscle atrophy provides direct evidence for the concept of muscle imbalance in phasic non-weight bearing muscles, a concept largely characterized based on clinical observation of patients. The susceptibility to this imbalance is demonstrated to be selective for the type IIb and IIx muscle fiber types. Overall, the study highlights the importance of considering muscle fiber number modulation and the effect of training on surrounding muscles in exercise comprised of SSCs.

Triceps surae elasticity modulus measured by shear wave elastography is not correlated to the plantar flexion torque.

Supersonic Shear Imaging (SSI) is a technique which analyses quantitatively the tissue properties in real time. The relation between joint torque and Young's modulus (E) of the agonist muscles is important for obtaining stratification values and ranges of normality. The aim of this study was to evaluate the intra and intersessions reliability of the E values of the Achilles tendon and medial gastrocnemius muscle, bilaterally, during rest, and correlate them with the isometric plantarflexion peak torque. Shear modulus maps were acquired bilaterally in Achilles tendon (AT) and medial gastrocnemius (MG) muscle of 24 healthy male volunteers. Two 5-second plantarflexion maximal voluntary contractions were performed with a 40-seconds interval and correlated with E values. a good intrasession reliability (intraclass correlation coefficient- ICC= 0.821-0.986) and a weak Pearson's correlation was found between E values and peak torque (r= 0.022 to -0.202) for both limbs (P > .05). E values cannot be predictive of the triceps surae force production in untrained men. It could be helpful, otherwise, to monitor a chronic strength adaptation after an exercise intervention or rehabilitation program. IIb, individual cohort study.