scholarly journals Can Eccentric Exercise of The Lower Limb Be Made More Efficiently, A Pilot Study.

2019 ◽  
pp. 1-8

Abstract Background: Eccentric Exercise has been shown to be more effective in building muscle and healing damaged tissue than concentric or isometric exercise. It has also been shown to be effective in increasing motor control. But the duration of therapeutic exercise in physical therapy is limited by insurance to 30-60 minutes a day. Objectives: Four standard therapy eccentric exercises of the lower limbs were compared (toe raise, ball exercise, side lying eccentric exercise and incline board exercise) to a trainer called the BTE Eccentron to see if the efficiency of exercise could be increased using one exercise session to meet or beat the four individual exercises. Subjects and Methods: The study examined eight randomly selected participants with no known medical conditions (neurological or orthopedic) that would preclude their participation (age=24.1+/-2.1 years height=168.9+/-6.4 cm BMI=23.2+/-3.2). EMG was used to assess muscle recruitment in each exercise. The muscles studies were the gastrocnemius, hamstring, hip adductors, and quadriceps muscles. Results: Muscle use on the eccentron was almost double that of the other exercises. Thus, making therapy more efficient. One single exercise bout showed more muscle activation during eccentric exercise than the other four exercises, with an average muscle use almost 4 times higher on the eccentron. Conclusion: The Eccentron offers a considerable advantage for clinical treatment making exercise and neuromuscular training more efficient.

2021 ◽  
Vol 6 (1) ◽  
pp. 16
Author(s):  
Kara B. Bellenfant ◽  
Gracie L. Robbins ◽  
Rebecca R. Rogers ◽  
Thomas J. Kopec ◽  
Christopher G. Ballmann

The purpose of this study was to investigate the effects of how limb dominance and joint immobilization alter markers of physical demand and muscle activation during ambulation with axillary crutches. In a crossover, counterbalanced study design, physically active females completed ambulation trials with three conditions: (1) bipedal walking (BW), (2) axillary crutch ambulation with their dominant limb (DOM), and (3) axillary crutch ambulation with their nondominant limb (NDOM). During the axillary crutch ambulation conditions, the non-weight-bearing knee joint was immobilized at a 30-degree flexion angle with a postoperative knee stabilizer. For each trial/condition, participants ambulated at 0.6, 0.8, and 1.0 mph for five minutes at each speed. Heart rate (HR) and rate of perceived exertion (RPE) were monitored throughout. Surface electromyography (sEMG) was used to record muscle activation of the medial gastrocnemius (MG), soleus (SOL), and tibialis anterior (TA) unilaterally on the weight-bearing limb. Biceps brachii (BB) and triceps brachii (TB) sEMG were measured bilaterally. sEMG signals for each immobilization condition were normalized to corresponding values for BW.HR (p < 0.001) and RPE (p < 0.001) were significantly higher for both the DOM and NDOM conditions compared to BW but no differences existed between the DOM and NDOM conditions (p > 0.05). No differences in lower limb muscle activation were noted for any muscles between the DOM and NDOM conditions (p > 0.05). Regardless of condition, BB activation ipsilateral to the ambulating limb was significantly lower during 0.6 mph (p = 0.005) and 0.8 mph (p = 0.016) compared to the same speeds for BB on the contralateral side. Contralateral TB activation was significantly higher during 0.6 mph compared to 0.8 mph (p = 0.009) and 1.0 mph (p = 0.029) irrespective of condition. In conclusion, limb dominance appears to not alter lower limb muscle activation and walking intensity while using axillary crutches. However, upper limb muscle activation was asymmetrical during axillary crutch use and largely dependent on speed. These results suggest that functional asymmetry may exist in upper limbs but not lower limbs during assistive device supported ambulation.


2020 ◽  
Vol 13 (5) ◽  
pp. 133-143
Author(s):  
Luciana Oliveira Dos Santos ◽  
Andréia Abud da Silva Costa ◽  
Renato Moraes

Background. Depending on the dimensions of a hole, the characteristics of the walking surface, and the position of the hole relative to normal walking, individuals may need to step into the hole with the dominant or non-dominant limb. Aim. We investigated the effect of the lower limb dominance in walking adaptations in the presence of a hole on the ground. Methods: Twenty young adults walked and stepped into a hole positioned in the middle of the pathway using the dominant and non-dominant lower limbs. Results. For the trailing limb, the impulses were not affected by the lower limb dominance, but for the leading limb, the non-dominant leg increased the braking and propulsive impulses compared to the dominant leg. On the other hand, toe-off velocity increased when the non-dominant leg was used as trailing and leading limbs. Stride speed increased when the non-dominant leg was the trailing limb. Interpretation. Our results were consistent with asymmetrical behavior between dominant and non-dominant legs. Although the differences between the dominant and non-dominant legs have not affected the success in the task, they can put the individual at higher risk of stumbling and consequently a fall when stepping with the non-dominant leg into the hole.


Author(s):  
Petr Hedbávný ◽  
Miriam Kalichová ◽  
Michal Rabenseifner ◽  
Adam Borek

In women’s artistic gymnastics, the balance beam belongs among the disciplines with the heaviest lower limbs load. The aim of our research was to disclose a lower limbs weekly load volume regarding load asymmetry, and to determine the take-off and landing reaction forces between landing ground and foot in selected gymnastic elements. In 9 female artistic gymnasts of junior and senior category one training week was video-recorded and analysed. The reaction forces were measured using 5 Bertec force plates in one female Czech nation-al team member. Based on the training video recordings 12 jump and acrobatic elements were analysed. Among the total of 422 recorded take-offs and landings 41% were performed from both legs, (BL), 44.5% from one lower limb (HL) and 14.5% from the other lower limb (LL). The maximum reaction force of the landing ground during take-offs was 2.4 BW in av-erage, 3.1 BW in landings. In asymmetrical elements, one leg was loaded three times more (538.3 BW) than the other (174.1 BW) in one training day in total. We recommend to record the load asymmetry in the course of the gymnastic trainings in order to choose and person-alise the appropriate regeneration process and compensational exercise.


2020 ◽  
Vol 28 (5) ◽  
pp. 521-532 ◽  
Author(s):  
Wei Li ◽  
Zhongli Li ◽  
Shuyan Qie ◽  
Huaqing Yang ◽  
Xuemei Chen ◽  
...  

BACKGROUND: Walking is a basic human activity and many orthopedic diseases can manifest with gait abnormalities. However, the muscle activation intervals of lower limbs are not clear. OBJECTIVE: The aim of this study was to explore the contraction patterns of lower limb muscles by analyzing activation intervals using surface electromyography (SEMG) during walking. METHODS: Four muscles including the tibialis anterior (TA), lateral gastrocnemius (LG), medial gastrocnemius (MG), and rectus femoris (RF) of bilateral lower extremity of 92 healthy subjects were selected for SEMG measurements. The number of activations (activation intervals) and the point of the highest root mean square (RMS) EMG signal in the percentage of the gait cycle (GC) were used to analyze muscle activities. RESULTS: The majority of TA and RF showed two activation intervals and both gastrocnemius parts three activation intervals during walking. The point of the highest RMS EMG signal in the percentage of the GC for TA, LG, MG and RF are 5%, 41%, 40%, and 8%, respectively. The activation intervals were mostly affected by age, height, different genders and bilateral limbs. CONCLUSION: This study identified the different activation intervals (four for each muscle) and the proportion of healthy adults in which they occurred during the normal gait cycle. These different activation intervals provided a new insight to evaluate the function of nerves and muscles. In addition, the activation interval and RMS peak time proposed in this study can be used as new parameters for gait analysis.


2021 ◽  
Author(s):  
Jack Martin

Aims In recent years there has been a significant rise in the popularity of muscle gun devices. However, the current research regarding handheld muscle gun devices is unclear. Therefore, this literature review will explore the current literature regarding the effect of muscle gun device on lower limb range of motion, muscle activation, force output and the possibility of reducing delayed onset muscle soreness. Methods Four databases were used along with two academic search engines to search for studies that satisfied the inclusion criteria. To fulfil the inclusion criteria studies had to be of a pre-post design with a focus on the use of percussion massage devices on lower limbs. Studies exploring range of motion and muscle force output were of particular interest. Results Thirty-nine included studies were used in this literature review. It was found that handheld percussive massage devices are the most effective method of increasing lower limb range of motion compared to foam rolling and other self-myofascial protocols. The use of handheld percussive massage devices directly after exercise reduces delayed onset muscle soreness. However, there was no reported significant increase in muscle activation or force output following the usage of a handheld percussive massage device. Conclusion The use of muscle gun devices is recommended as part of a structured warm-up pre-exercise due to an increase in range of motion, reduction in perceived muscle soreness whilst having no negative impact on muscle activation and force output. Muscle guns may also be implemented as part of a rehabilitation programme post injury due to their ability to increase range of motion and reduce perceived pain and muscle soreness.


2019 ◽  
Vol 121 (1) ◽  
pp. 163-176 ◽  
Author(s):  
Magdalena Zych ◽  
Ian Rankin ◽  
Donal Holland ◽  
Giacomo Severini

Motor adaptations are useful for studying the way in which the lower limbs are controlled by the brain. However, motor adaptation paradigms for the lower limbs are typically based on locomotion tasks, where the necessity of maintaining postural stability is the main driver of adaptation and could possibly mask other underlying processes. In this study we investigated whether small temporal or spatial asymmetries can trigger motor adaptations during stationary cycling, where stability is not directly compromised. Fourteen healthy individuals participated in two experiments: in one of the experiments, the angle between the crank arms of the pedals was altered by 10° to induce a temporal asymmetry; in the other experiment, the length of the right pedal was shortened by 2.4 cm to induce a spatial asymmetry. We recorded the acceleration of the crank arms and the electromographic signals of 16 muscles (8 per leg). The analysis of the accelerometer data was used to investigate the presence of motor adaptations. Muscle synergy analysis was performed on each side to quantify changes in neuromuscular control. We found that motor adaptations are present in response to temporal asymmetries and are obtained by progressively shifting the activation patterns of two synergies on the right leg. Spatial asymmetries, on the other hand, appear to trigger a feedback-driven response that does not present an aftereffect. This response is characterized by a steplike decrease in activity in the right gastrocnemius when the asymmetry is present and likely reflects the altered task demands. NEW & NOTEWORTHY The processes driving lower limb motor adaptations are not fully clear, and previous research appears to indicate that adaptations are mainly driven by stability. We show that lower limb adaptations can be obtained also in the absence of an explicit balance threat. We also show that adaptations are present when kinematic error cannot be compensated for, suggesting the presence of intrinsic error measures regulating the timing of activation of the two legs.


2019 ◽  
Vol 32 ◽  
Author(s):  
Jaqueline Santos Silva Lopes ◽  
Aryane Flauzino Machado ◽  
Allysiê Priscila Cavina ◽  
Jéssica Kirsch Michelletti ◽  
Aline Castilho de Almeida ◽  
...  

Abstract Introduction: Muscle injuries show an incidence associated with extreme stretching, or even a high-intensity eccentric contraction. Such injuries cause severe damage to athletes, including lower performance, withdrawal, and psychological distress. In this scenario, the study of effective preventive methods is an indispensable factor in the routine of professional athletes, to reduce the incidence of injuries. Objective: To verify the effectiveness of three different interventions (warm-up, neuromuscular training, and eccentric exercise) to prevent muscle injuries in the lower limbs. Method: We searched the Cochrane Library, EMBASE, SPORTDiscus, PEDro, and PubMed databases from the earliest records until January 20, 2018. The search was performed from word combinations such as clinical trial, muscle strain, injury prevention. The data related to the outcome of prevention were grouped in meta-analysis and described in Risk Ratio (RR) with 95% confidence interval. Results: Sixteen studies were included: five assessed eccentric exercise, three investigated neuromuscular training, and eight observed warm-up. The eccentric exercise (RR = 3.49, 95% CI 2.36, 5.16, p < 0.00001) and the neuromuscular training (RR = 2.73, 95% CI 2.03, 2.68, p < 0.00001) showed significant effects on the prevention of muscle injuries in lower limbs. On the other hand, warm-up (RR = 1.57, 95% CI 0.92, 2.7, p = 0.10) was irrelevant in reducing the incidence of injuries in the body segment investigated. Conclusion: The outcomes presented provide clinical relevance inherent in the field practices, with intrinsic potential for practical application in the management of specific preventive techniques.


Trials ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Natália Camin Silva ◽  
Matheus de Castro Silva ◽  
Morisa Garcia Guimarães ◽  
Manoela Beatriz de Oliveira Nascimento ◽  
Lilian Ramiro Felicio

Abstract Background Patellofemoral pain (PFP) often affects young women, and the etiology is multifactorial and poorly understood. Conservative intervention has been focused on risk factors or aggravating factors and is composed of hip- and knee-strengthening exercises, as this population often has muscle weakness and poor motor control during daily and sports activities. The objective of this study was to evaluate the additional effects of neuromuscular training in a conservative treatment of trunk-, hip-, and knee-muscle strengthening on pain, function, and kinematics of the trunk, pelvis, and lower limb in women with PFP. Methods This is a randomised clinical trial, controlled, blinded. Ninety women who are active and engage in physical activity up to twice a week will be recruited. All participants will undergo an individual physiotherapy assessment and then will be allocated randomly into two groups. Thereafter, both groups will undergo a 12-week intervention protocol: group 1 will perform strengthening exercises for the trunk, hip, and knee muscles, while group 2 will receive the same treatment, with the inclusion of neuromuscular training exercises on the fourth week. At the end of the intervention, the volunteers will be evaluated. The primary outcomes will be pain intensity (using a Visual Analog Scale: over the last month, squat 90°, and step of 26 cm during 1 min), functional capacity (Anterior Knee Pain Scale and Activities of Daily Living Scale), and 2D kinematics of the trunk, pelvis, and lower limb during the single-leg squat. The secondary outcomes correspond to the isometric muscular strength of the lower limb and the level of satisfaction from the intervention. Discussion The present study was initiated on 28 January 2018 and is currently in progress, scheduled for completion in July 2019. The results of this study should contribute to the physiotherapeutic treatment of women with PFP by aggregating information on the benefits of adding neuromuscular training to strengthening of the trunk and lower-limb muscles. Trial registration Registro Brasileiro de Ensaios Clínicos, ID: RBR-8c7267. Registered on 2 August 2017.


Author(s):  
Fan Li ◽  
Wei Huang ◽  
Xingsheng Wang ◽  
Xiaojiang Lv ◽  
Fuhao Mo

Accident data shows that driver’s kinematics response in real accidents can be significantly different from that in dummy or cadaver tests because of driver’s muscle contraction. In this study, a finite element human-body model consisting of an upper body of a dummy model and a lower limb–pelvis biomechanical model with three-dimensional active muscles was developed to investigate in depth the lower-limb injuries. Driver’s emergency reaction during frontal impact was simulated by modelling muscle active contraction based on a series of volunteer experimental tests. Besides, a realistic impact environment with the response of the restraint system and the invasion of the driver’s compartment was established in this study. The results show that muscle contraction can cause extra loads on lower limbs during the impact, which can increase the injury risk of lower limbs. As for the femur injury, muscle contraction caused an additional 1 kN axial load on the femur, and the femur resultant bending moment of active models was also higher by about 10–40 N m. Besides, the tibial index of the model with muscle activation was about 0.1 higher. In addition, the results indicate that the femur injury is strongly related to the combined action of both axial force and bending moment. The variation of the injury tolerance along the tibia shaft should be considered when evaluating the tibia injury. Overall, the current lower-limb injury criteria can be still the lack of robustness.


Healthcare ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 465
Author(s):  
Ukadike C. Ugbolue ◽  
Emma L. Yates ◽  
Kerensa Ferguson ◽  
Scott C. Wearing ◽  
Yaodong Gu ◽  
...  

Only a small number of muscle activation patterns from lower limbs have been reported and simultaneous muscle activation from several lower limb muscles have not yet been investigated. The purpose of this study was to examine any gender differences in surface electromyography (EMG) activity from six recorded lower limb muscles of the dominant limb at baseline (i.e., with the foot placed flat on the floor and in the neutral position), and during concentric and eccentric phases when performing a heel raise task. In total, 10 females and 10 males performed a standing heel raise task comprising of three continuous phases: baseline, unloading (concentric muscle action), and loading (eccentric muscle action) phases. Muscle activation from six muscles (gastrocnemius medialis, gastrocnemius lateralis, soleus, tibialis anterior, peroneus longus, and peroneus brevis) were measured using the Myon 320 EMG System. Root mean squared values of each muscle were calculated for each phase. Descriptive and inferential statistics were incorporated into the study. Statistically significant p values were set at 0.05. The results showed no significant differences between baseline, concentric, and eccentric phases with respect to each of the muscles investigated. Except for the gastrocnemius medialis at baseline and concentric phases, no significant differences were observed between genders or contractions. The data suggests that gender does not significantly influence the eccentric phase during the standing heel raise task.


Sign in / Sign up

Export Citation Format

Share Document