Increasing cadence with a metronome and running barefoot changes the sagittal kinematics of the lower limbs and trunk.

The purpose was to compare two non-laboratory based running retraining programs on lower limb and trunk kinematics in recreational runners. Seventy recreational runners (30 ± 7.3 years old, 40% female) were randomised to a barefoot running group (BAR), a group wearing a digital metronome with their basal cadence increased by 10% (CAD), and a control group (CON). BAR and CAD groups included intervals from 15 to 40 min over 10 weeks and 3 days/week. 3D sagittal kinematics of the ankle, knee, hip, pelvis, and trunk were measured before and after the retraining program, at comfortable and high speeds. A 3 × 2 mixed ANOVA revealed that BAR and CAD groups increased knee and hip flexion at footstrike, increased peak hip flexion during stance and flight phase, decreased peak hip extension during flight phase, and increased anterior pelvic tilt at both speeds after retraining. In addition, BAR increased ankle plantar flexion at footstrike and increased anterior trunk tilt. Both retraining programs demonstrated significant moderate to large effect size changes in parameters that could reduce the mechanical risks of injury associated with excessive knee stress, which is of interest to coaches, runners and those prescribing rehabilitation and injury prevention programs.

Minimizing risk of iatrogenic nerve injury during peroneus longus tendon autograft harvest: a cadaveric study at different ankle or knee positions.

PURPOSE: To evaluate the distances using ultrasound between the superficial peroneal nerve (SPN) and sural nerve along the peroneus longus tendon (PLT) autograft harvest path at different ankle or knee positions in order to minimize risk of iatrogenic nerve injury during PLT autograft harvest. METHODS: Twenty-four fresh-frozen human cadaveric lower extremities were used to harvest a full-thickness PLT autograft with a tendon stripper. Four specimens were utilized to validate correct identification of nerves under ultrasound. Sonographically guided perineural injections were performed at the start point and end point of the PLT harvest path using coloured latex, followed by dissection with gross inspection. Using ultrasound, the distance from the peroneus brevis muscle to the sural nerve at different ankle positions (20° dorsiflexion, neutral, and 20° plantarflexion) was measured, and the distance from the end of the tendon stripper to the SPN at different knee positions (full extension and 90° flexion) was also measured. Measurements were performed by two separate observers using ImageJ software. RESULTS: Cadaveric dissection showed the presence of latex around nerves in all four specimens. The average distance from the brevis muscle to the sural nerve increased significantly from dorsiflexion to plantarflexion. The shortest distance from the tenodesis site to the sural nerve was 5.8 ± 1.7 mm. There was no significant difference from the end of the tendon stripper to the SPN between full extension or 90° flexion of the knee. CONCLUSION: When harvesting the PLT, it is recommended to place the ankle at plantarflexion. The knee at full extension or 90° flexion had no effect. Joint positions at the time of graft harvest should be monitored to reduce risks of iatrogenic nerve injury.

Ankle muscle strength influence on muscle activation during dynamic and static ankle training modalities.

Muscle weakness is considered a risk factor for ankle injury. Balance training and barefoot running have been used in an attempt to strengthen the muscles crossing the ankle. It is expected that training tasks that successfully strengthen the ankle would elicit increased muscular activity. However, it is unknown how an individual's ankle strength will influence the muscle activity used during a given task. Twenty-six participants performed dynamic (shod, barefoot running) and static tasks (squat on ground, squat on ®Bosu Ball) believed to strengthen the muscles surrounding the ankle. Electromyographic signals of the tibialis anterior, peroneus longus, gastrocnemius lateralis (GL) and gastrocnemius medialis (GM) were recorded and analysed using a non-linearly scaled wavelet analysis. Participants were divided into a strong group and a weak group according to their isometric plantar-flexion torque. The weak group required more relative GL and GM muscle activity during each training task compared to the strong group. No difference was observed between shod and barefoot running. There was a significant effect of training task on muscle activation level for the weak group. Differences in ankle strength had a significant impact on muscle activation.

Effects of Ankle Kinesio Taping on Postural Control in Stroke Patients.

BACKGROUND: To investigate the effects of kinesio taping on postural control in stroke patients. MATERIALS AND METHODS: Forty stroke patients aged 30 to 60 years were randomly divided into an experimental and a control group. In the experimental group, kinesio tape (KT) was applied directly on the skin over the affected ankle in the direction of dorsiflexion and eversion to correct the equinovarus deformity. The tape was kept on the ankle for 1 day. The results were measured with the forward reach test, lateral reach test, Berg Balance Scale (BBS), and timed up and go test. Center of pressure (COP) displacement and velocity were also measured while the patients stood on a force plate. All variables were measured on the first day immediately after taping and 24 hours later in the KT group, and on the first day and also 24 hours later in the control group. RESULTS: There was a statistically significant difference in BBS between the first day and 24 hours later in the KT group (P = .01). The forward reach test and mediolateral displacement of the COP differed significantly after taping in the experimental group compared to the control group (P = .04). Immediately after taping, BBS improved significantly in the KT group (P = .02). CONCLUSIONS: The application of KT improved forward reach test results and displacement of the COP in stroke patients.

Greater lower limb flexion in gymnastic landings is associated with reduced landing force: a repeated measures study.

High impact forces during gymnastic landings are thought to contribute to the high rate of injuries. Lower limb joint flexion is currently limited within gymnastic rules, yet might be an avenue for reduced force absorption. This study investigated whether lower limb flexion during three gymnastic landings was related to force. Differences between landings were also explored. Twenty-one elite women's artistic gymnasts performed three common gymnastic techniques: drop landing (DL), front and back somersaults. Ankle, knee, and hip angles, and vertical ground reaction force [(vGRF) magnitude and time to peak], were measured using three-dimensional motion analysis and force platform. The DL had significantly smaller peak vGRF, greater time to peak vGRF and larger lower limb flexion ranges than landing from either somersault. Peak vGRF and time to peak vGRF were inversely related. Peak vGRF was significantly reduced in gymnasts who landed with greater hip flexion, and time to peak was significantly increased with increasing ankle, knee, and hip flexion. Increased range of lower limb flexion should be encouraged during gymnastic landings to increase time to peak vGRF and reduce high impact force. For this purpose, judging criteria limitations on lower limb flexion should be reconsidered.

Measuring kinematic changes of the foot using a gyro sensor during intense running.

Gyro sensor has been used to measure foot pronation during running with reliable results in previous studies, and the signals were not affected by the vibration of heel strikes. The purpose of this study was to observe the kinematic changes of the foot during intense running using a 3-axis gyro sensor. Fifteen male participants (average age: 24.5 ± 1.7 years; mean height: 174.1 ± 3.3 cm; mean body weight: 71.0 ± 5.5 kg) were recruited in this study. Foot kinematic changes were observed in 30-min intense running protocols. The comparisons of the signals from gyro and motion analysis system were also performed to determine the accuracy of the gyro and showed positive results. In the main experiment, the ankle range of motion (ROM) in the frontal plane, measured using a motion system, showed a significant increase over time. Accordingly, peak angular velocity in the frontal plane also showed a significant increase. The correlation between ankle ROM and peak angular velocity in the frontal plane is significantly high (r = 0.975). Moreover, peak angular velocity in the frontal plane is also significantly correlated with both rate of perceived exertion (RPE) (r = 0.911) and heart rate (r = 0.960). This study concluded that an alarm system for foot kinematic changes related to running injuries can be built based on the peak angular velocity of the foot in the frontal plane.

Effects of 6 weeks of whole-body vibration training on ankle motor control: a randomized controlled trial.

BACKGROUND: Interventions on ankle motor control are important to prevent recurrent ankle sprains. Training using whole-body vibration may easily and effectively improve ankle motor control, but the effects have not been investigated. Therefore, this study aimed to clarify the effects of 6 weeks of training with whole-body vibration on ankle motor control in a dynamic movement task among healthy participants. METHODS: Twenty healthy university students (6 males and 14 females) were randomly allocated to whole-body vibration training and control groups, with 10 participants in each group. The training was performed twice a week for 6 weeks in both groups. Primary outcome was mean ankle angular jerk cost in the star excursion balance test. Secondary outcomes were maximum ankle motion angle and maximum reach distance in the star excursion balance test, ankle proprioception, and range of ankle dorsiflexion motion in the loaded position. RESULTS: There was a significant group × period (pre- and postintervention) interaction for mean ankle angular jerk cost in the direction of ankle abduction/adduction during posterolateral reaching, which was significantly lower at postintervention than that at preintervention in the whole-body vibration group In the whole-body vibration group, the maximum ankle dorsiflexion motion angle during anterior and posterolateral reaching was significantly higher at postintervention than that at preintervention. CONCLUSIONS: Training with whole-body vibration improves ankle motor control in dynamic movement tasks, although the direction of reach and plane of motion are limited. Additionally, training with whole-body vibration is also effective in increasing the ankle dorsiflexion angle during dynamic movement tasks.

In vivo graft tension in anatomic double-bundle anterior cruciate ligament reconstruction during active leg-raising motion with the knee splinted.

PURPOSE: The purpose of this study was to measure the in vivo graft tension in anatomic 2-bundle anterior cruciate ligament (ACL) reconstruction during active leg-raising exercise with the knee immobilized. METHODS: Anatomic double-bundle ACL reconstruction was performed with autogenous semitendinosus tendons in 7 patients while under general anesthesia. Two grafts were fixed with 2 EndoButton-CL devices (Smith & Nephew Endoscopy, Andover, MA) on the femur and were temporarily fixed to 2 tension-adjustable force gauges on the anterior tibial cortex. Then, a knee brace in semi-flexion was put around the knee, and 10 N of initial tension was applied to each graft at 20° of flexion. The tension on the anteromedial (AM) and posterolateral (PL) grafts was continuously measured during active leg-raising motion with the knee immobilized after patients had awoken from anesthesia. Then, the tension measurement was repeated during active leg-raising motion with the knee immobilized while a 2-kg weight was fitted around the ankle. RESULTS: In situ graft tension during active leg-raising motion with a knee brace was 10.9 ± 4.0 N for the AM graft and 8.6 ± 5.1 N for the PL graft, whereas the tension with a 2-kg weight around the ankle was 10.9 ± 3.4 N for the AM graft and 9.9 ± 3.6 N for the PL graft. There was no significant difference between each graft in the 2 motions with a paired t test. CONCLUSIONS: Graft tension with the knee immobilized with a semi-flexed knee brace during active leg-raising motion was 19.5 N with no weight and 20.8 N with additional weight, both of which were almost equal to the initial graft tension at the time of fixation at 20°. Thus the leg-raising exercise can be recommended as safe when a semi-flexed knee brace is worn after ACL reconstruction. CLINICAL RELEVANCE: These findings will help to plan postoperative rehabilitation programs with security.

Is the inverted surface landing more suitable in evaluating ankle braces and ankle inversion perturbation?

OBJECTIVE: To investigate biomechanical (kinematic) differences between 2 ankle brace testing protocols: landing on an inverted surface (IS) and inversion drop on an inversion platform. DESIGN: Five trials in each of 4 dynamic movement conditions were performed: inversion drop and drop landing from 0.45 m onto an IS without and with an ankle brace. A 7-camera motion analysis system was used to obtain the 3-dimensional kinematics. A 2 × 2 (brace × movement) repeated measures analysis of variance was used to evaluate selected variables for inversion drop and IS landing. SETTING: Research laboratory. PATIENTS: Eleven healthy subjects participated in the study. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Maximum ankle frontal plane and sagittal plane joint angles, range of motion, and maximum angular velocity. RESULTS: The IS landing resulted in significantly earlier maximum inversion, inversion velocities, dorsiflexion range of motion (ROM), contact dorsiflexion velocity, and maximum dorsiflexion velocity compared with the inversion drop. The ankle brace application during the IS landing reduced the contact plantarflexion angle, dorsiflexion ROM and maximum dorsiflexion velocity, and maximum inversion. CONCLUSIONS: The results from this study showed that the IS landing protocol produced significantly earlier maximum inversion angle and velocity and inversion velocities compared with the inversion drop protocol. These results showed that the IS landing is more demanding and should be considered in future investigations of ankle braces and lateral ankle performance/injury mechanisms.

Active robotic training improves locomotor function in a stroke survivor.

BACKGROUND: Clinical outcomes after robotic training are often not superior to conventional therapy. One key factor responsible for this is the use of control strategies that provide substantial guidance. This strategy not only leads to a reduction in volitional physical effort, but also interferes with motor relearning. METHODS: We tested the feasibility of a novel training approach (active robotic training) using a powered gait orthosis (Lokomat) in mitigating post-stroke gait impairments of a 52-year-old male stroke survivor. This gait training paradigm combined patient-cooperative robot-aided walking with a target-tracking task. The training lasted for 4-weeks (12 visits, 3 × per week). The subject's neuromotor performance and recovery were evaluated using biomechanical, neuromuscular and clinical measures recorded at various time-points (pre-training, post-training, and 6-weeks after training). RESULTS: Active robotic training resulted in considerable increase in target-tracking accuracy and reduction in the kinematic variability of ankle trajectory during robot-aided treadmill walking. These improvements also transferred to overground walking as characterized by larger propulsive forces and more symmetric ground reaction forces (GRFs). Training also resulted in improvements in muscle coordination, which resembled patterns observed in healthy controls. These changes were accompanied by a reduction in motor cortical excitability (MCE) of the vastus medialis, medial hamstrings, and gluteus medius muscles during treadmill walking. Importantly, active robotic training resulted in substantial improvements in several standard clinical and functional parameters. These improvements persisted during the follow-up evaluation at 6 weeks. CONCLUSIONS: The results indicate that active robotic training appears to be a promising way of facilitating gait and physical function in moderately impaired stroke survivors.

Which Frequency of Ankle Pump Exercise Should Be Chosen for the Prophylaxis of Deep Vein Thrombosis?

INTRODUCTION: Ankle pump exercise (APE) is an effective method to prevent deep vein thrombosis (DVT) in the lower extremities. However, traditional APE at a frequency of 3 times/min applied in the clinic lacked high compliance, and individuals were found to prefer an APE of 30 times/min. This study aimed to compare the effects of APEs with the above two different frequencies on the venous hemodynamics and fatigue of lower extremities. METHODS: The study applied a randomized cross-over design, and 307 healthy adults were randomly assigned into two groups, whose left feet performed 5 minutes of traditional APE (3 times/min, after 10 minutes of rest) and 5 minutes of selected APE (30 times/min, after 10 minutes of rest) in different orders. The diameters and blood flow velocities of the external iliac vein, femoral vein, and popliteal vein of the left extremities were recorded with the color doppler ultrasound when participants were at rest and after 5 minutes of traditional or selected APE. The fatigue of lower extremities was assessed with the Rating of Perceived Exertion (RPE) after the participants performed 5 minutes of different APEs. RESULTS: After both traditional APE and selected APE, the diameters and blood flow (peak systolic) velocities of the external iliac vein, femoral vein, and popliteal vein increased significantly in the participants (P<.01), and the effects of the two APEs on venous hemodynamics of the lower extremities had no significant difference (P>.05). However, participants reported that traditional APE caused higher fatigue, and 252 (82.1%) participants preferred APE at 30 times/min. CONCLUSION: Both traditional and selected APE could increase venous blood flow in the lower extremity. Despite the equivalent effects, the selected APE of 30 times/min may cause less fatigue than the traditional one of 3 times/min.

Leg Dominance Does Not Influence Maximal Force, Force Steadiness, or Motor Unit Discharge Characteristics.

PURPOSE: The aim of our study was to compare maximal force, force steadiness, and discharge characteristics of motor units in tibialis anterior during contractions with the dorsiflexors of the dominant and nondominant legs at low-to-moderate target forces and three ankle angles. METHODS: Twenty young adults performed maximal and submaximal isometric contractions (5%, 10%, 20%, 40%, and 60% of maximal voluntary contraction (MVC)) with the dorsiflexors of the dominant and nondominant legs at three ankle angles (75°, short length; 90°, intermediate length; 105°, long length). High-density EMG signals from the tibialis anterior muscle of each leg were recorded. RESULTS: Maximal force (average dominant, 182.9 ± 64.5 N; nondominant, 179.0 ± 58.8 N) and the fluctuations in force, quantified as absolute (SD) and normalized amplitudes (coefficient of variation (CoV)), were similar between the two legs across the three ankle angles (average CoV for dominant, 1.5% ± 1.0%; nondominant, 1.7% ± 1.3%). The CoV for force for both legs decreased from 5% to 20% MVC force, and then it plateaued at 40% and 60% MVC force. EMG amplitude, mean discharge rate of motor units, discharge variability (interspike interval), and the variability in neural drive (filtered cumulative spike train) were similar between the two legs across the submaximal contractions. CONCLUSIONS: MVC force and force steadiness were similar across ankle angles and target forces between the dominant and nondominant legs. The attributes that underlie the self-reported identification of a dominant leg were not associated with the force capacity or the control of force for the dorsiflexor muscles, at least during isometric contractions.

Effects of the FIFA 11+ on ankle evertors latency time and knee muscle strength in amateur futsal players.

Background: The FIFA 11+ has shown to increase muscle strength and reduce injury risk. The purpose of this study was to assess the short and long-term effects of the FIFA 11+ on knee strength, and muscle latency after sudden inversion of amateur futsal players.Methods: Seventy-one male futsal players were recruited and randomized to a FIFA 11+ (n = 37, age: 27.0 ± 5.1 years) and a control group (n = 34, age: 26.0 ± 5.1 years). The FIFA 11+ programme was executed twice a week, for 10 weeks, followed-up after 10 weeks where both groups executed regular warm-ups. Concentric and eccentric isokinetic knee muscle strength was tested and latency time of the evertor muscles after sudden inversion of the ankle was executed with a trapdoor mechanism following an EMG protocol of selected leg muscles (peroneus brevis and peroneus longus).Results: No significant difference were observed between groups for short-term changes in isokinetic strength after adjustment for baseline differences. At long-term, significant gains were obtained after adjustment for baseline differences in eccentric strength for both lower limbs as for the H/Q ratios for the dominant limb. No changes between groups were observed in the peroneus brevis and peroneus longus latency time.Conclusions: Performing FIFA 11+ did not have short-term effects on knee strength and muscle latency after sudden inversion in amateur futsal players. However, significant long-term benefits were observed for eccentric strength and H/Q ratios.

Ankle taping can reduce external ankle joint moments during drop landings on a tilted surface.

Ankle taping is commonly used to prevent ankle sprains. However, kinematic assessments investigating the biomechanical effects of ankle taping have provided inconclusive results. This study aimed to determine the effect of ankle taping on the external ankle joint moments during a drop landing on a tilted surface at 25°. Twenty-five participants performed landings on a tilted force platform that caused ankle inversion with and without ankle taping. Landing kinematics were captured using a motion capture system. External ankle inversion moment, the angular impulse due to the medio-lateral and vertical components of ground reaction force (GRF) and their moment arm lengths about the ankle joint were analysed. The foot plantar inclination relative to the ground was assessed. In the taping condition, the foot plantar inclination and ankle inversion angular impulse were reduced significantly compared to that of the control. The only component of the external inversion moment to change significantly in the taped condition was a shortened medio-lateral GRF moment arm length. It can be assumed that the ankle taping altered the foot plantar inclination relative to the ground, thereby shortening the moment arm of medio-lateral GRF that resulted in the reduced ankle inversion angular impulse.

Multicomponent Training Program with High-Speed Movement Execution of Ankle Muscles Reduces Risk of Falls in Older Adults.

The purpose of this study was to investigate the effects of multicomponent training program, designed to improve the torque around the ankle joint performing high-speed movement execution, on healthy older adults. Participants were balanced by torque around the ankle joint and randomly allocated to either exercise (n = 12, 69.7 ± 4.8 years, 74.6 ± 16.8 kg, 1.63 ± 0.10 m) or control group (CG) (n = 14, 70.86 ± 6.48 years; 73.5 ± 13.4 kg, 1.56 ± 0.05 m). The exercise group (EG) performed a multicomponent training of resistance, agility, and coordination exercises, focusing on the plantar flexor muscles during 12 weeks (3 days per week). Outcome measures were torque (plantar flexion and extension), reactive capacity (Step test), and functional mobility (gait and timed up and go [TUG] test). The training program was induced to increase peak torque of extensor muscles around the ankle joint to EG (Δ = 50%; d = 1.59) compared to the CG. Such improvement was converted to reactive capacity improvements considering the decrease in the execution time of the Swing phase and in the Total time of the Step test (Δ = 19%; d = 0.93, Δ = 14%; d = 1.02, respectively). Gains in functional mobility were verified by the increase of the walking speed (Δ = 15%; d = 1.37) and by the smaller time of execution of TUG test (Δ = 17%; d = 1.73) in the EG. Therefore, the multicomponent training was effective to reduce or to reverse muscular age-related declines, which are associated with functional capacity and reduction of fall risk in older adults.

An integrated core training program improves joint symmetry and metabolic economy in trained runners.

BACKGROUND: Over 60 million Americans participate in running as a form of exercise or sport annually, making it the most popular form of physical activity in the country. Although there are numerous health benefits from a regular running routine, it is also an activity associated with a high risk of injury. Multiple factors, such as core muscle weakness and stride asymmetry, contribute to running injuries and loss of performance. The aim of this study was to assess how an integrated, functional core training intervention affects the components of performance (metabolic economy and speed) as well as a risk factor associated with injury (range of motion joint asymmetry). We hypothesized that economy, 5-km speed, and range of motion symmetry would increase in runners who added a 6-week integrated core-training intervention to their routine compared to a control group who simply maintained their current running routine. METHODS: Twelve, healthy adult runners participated in the study and six of these participants completed the exercise intervention. Heart rate data were collected to estimate metabolic economy while kinematic data were collected to calculate joint range of motion asymmetry. RESULTS: Our data demonstrated that running asymmetry decreased by a statistically significant 60% at the ankle in the sagittal plane while economy was 3% greater on both level and incline surfaces. CONCLUSIONS: In summary, runners who completed the 6-week integrated, functional training intervention improved economy, 5-km speed, and range of motion symmetry in comparison to the runners who simply maintained their current training routine.

Altered Neural Control Reduces Shear Forces and Ankle Impedance on a Slippery Surface.

OBJECTIVE: This study investigated the consequences of reduced ankle muscle activity on slippery surfaces. We hypothesized that reduced activation would reduce shear forces and ankle impedance to improve contact and reduce slip potential. METHODS: Data were collected from unimpaired adults walking across non-slippery and slippery walkways. Set within the walkway was a robotic platform with an embedded force plate for collecting shear forces and estimating the mechanical impedance of the ankle; impedance was characterized by a model with stiffness, damping, and inertia. RESULTS: We found a significant reduction in shear force due to reduced muscle activity in late mid-stance. We found no significant difference in stiffness between the surfaces. However, the muscle activation changes that contributed to shear force modulation occurred in late mid-stance, where reliable impedance estimates could not be made due to the foot leaving the measurement platform. When impedance could be measured, we found that a change in muscle activity predicted a change in stiffness, providing indirect estimates that stiffness was likely reduced later in stance. CONCLUSION: These results suggest that reduced muscle activity on slippery surfaces serves to reduce shear forces, and possibly also stiffness, during late mid-stance. SIGNIFICANCE: These results have implications for identifying and training likely fallers, and possibly for designing prosthetic systems that help prevent falls when walking across different terrains.

High Plantar Force Loading After Achilles Tendon Rupture Repair With Early Functional Mobilization.

BACKGROUND: Mechanical loading is essential for tendon healing and may explain variability in patient outcomes after Achilles tendon rupture (ATR) repair. However, there is no consensus regarding the optimal postoperative regimen, and the actual amount of loading during orthosis immobilization is unknown. PURPOSE: The primary aim of this study was to assess the number of steps and the amount of loading in a weightbearing orthosis during the first 6 weeks after surgical ATR repair. A secondary purpose was to investigate if the amount of loading was correlated to fear of movement and/or experience of pain. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Thirty-four patients (mean ± SD age, 38.8 ± 8.7 years) with ATR repair were included. Early functional mobilization was allowed postoperatively in an orthosis with adjustable ankle range of motion. During the first postoperative 2 weeks, patient-reported loading and pain were assessed with a visual analog scale and step counts with a pedometer. At the 2- and 6-week follow-up, a mobile force sensor was used for measuring plantar force loading, and the Tampa Scale for Kinesiophobia was used to examine fear of movement. RESULTS: Between the first and second weeks, there was a significant increase in the mean number of daily steps taken (from 2025 to 2753, P < .001) as well as an increase in self-reported loading (from 20% to 53%, P < .001). Patient self-reported loading was significantly associated with the plantar force measurement (rho = 0.719, P < .001). At 6 weeks, loading was 88.2% on the injured limb versus the uninjured limb. Fear of movement was not correlated with pedometer data, subjective loading, pain, or force data. Patients with less pain during activity, however, reported significantly higher subjective load and took more steps ( P < .05). CONCLUSION: This is the first study to demonstrate the actual loading patterns during postoperative functional mobilization among patients with surgically repaired ATR. The quick improvements in loading magnitude and frequency observed may reflect improved tendon loading essential for healing. Pain, rather than fear of movement, was associated with the high variability in loading parameters. The data of this study may be used to improve ATR rehabilitation protocols for future studies. REGISTRATION: NCT02318472 (ClinicalTrials.gov).

Effect of Compression Garments on the Development of Delayed-Onset Muscle Soreness: A Multimodal Approach Using Contrast-Enhanced Ultrasound and Acoustic Radiation Force Impulse Elastography.

BACKGROUND: Delayed-onset muscle soreness (DOMS) is one of the most common reasons for impaired muscle performance in sports. However, little consensus exists regarding which treatments may be most effective, and the underlying mechanisms are poorly understood. OBJECTIVES: To investigate the influence of compression garments on the development of DOMS, focusing on changes in muscle perfusion and muscle stiffness. METHODS: In this controlled laboratory study with repeated measures, muscle perfusion and stiffness, calf circumference, muscle soreness, passive ankle dorsiflexion, and creatine kinase levels were assessed in participants before (baseline) a DOMS-inducing eccentric calf exercise intervention and 60 hours later (follow-up). After DOMS induction, a sports compression garment (18-21 mmHg) was worn on 1 randomly selected calf until follow-up, while the contralateral calf served as an internal control. Muscle perfusion was assessed using contrast-enhanced ultrasound (peak enhancement and wash-in area under the curve), while muscle stiffness was assessed using acoustic radiation force impulse (shear-wave velocities). A magnetic resonance imaging scan of both lower legs was also performed during the follow-up testing session to characterize the extent of exercise-induced muscle damage. Comparisons were made between limbs and over time. RESULTS: Shear-wave velocity values of the medial gastrocnemius showed a significant interaction between time and treatment (P = .006), with the noncompressed muscle demonstrating lower muscle stiffness values at follow-up compared to baseline or to the compressed muscle. No significant differences in soleus muscle stiffness were noted between limbs or over time, as was the case for muscle perfusion metrics (peak enhancement and wash-in area under the curve) for the medial gastrocnemius and soleus muscles. Further, compression had no significant effect on passive ankle dorsiflexion, muscle soreness, calf circumference, or injury severity, per magnetic resonance imaging. CONCLUSION: Continuous wearing of compression garments during the inflammation phase of DOMS may play an important role in regulating muscle stiffness; however, compression garments have no significant effects on intramuscular perfusion or other common clinical assessments. J Orthop Sports Phys Ther 2018;48(11):887-894. Epub12 Jun 2018. doi:10.2519/jospt.2018.8038.

Effects of a group-based exercise program on the physical performance, muscle strength and quality of life in older women.

This study was aimed at determining the effect of a group-based exercise program on the physical performance, muscle strength and quality of life (QoL) in older women. Twenty women performed an exercise program for 8 weeks, at the rehabilitation unit. Outcome measures included a 4-m and 20-m walk test, a 6-min walk test, stair climbing and chair rise time, timed up and go test, isokinetic muscle testing of the knee and ankle, and the short form-36 (SF-36) and geriatric depression scale (GDS) questionnaires. The mean age of the study group was 70.3+/-6.5 years. After the completion of the exercise program, all of the physical performance tests and the SF-36 scores for the participants showed statistically significant improvements (p<0.05). In the isokinetic evaluations, most of angular velocities showed a significant increase in the peak torque (PT) values for knee extension and flexion, and for ankle plantar flexion (p<0.05). We concluded that this exercise program, when applied to older women, resulted in improved physical performance, increased muscle strength measured in both the knee and ankle, and improvement in the scores, estimating the QoL. We have shown that this exercise program is both effective and reliable for this age group of women.