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Results for “Muscle Strength Dynamometer”

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At least 19 recordsLinked to original sources

PubMed2004

Long-term outcome of muscle strength in ulnar and median nerve injury: comparing manual muscle strength testing, grip and pinch strength dynamometers and a new intrinsic muscle strength dynamometer.

OBJECTIVE: To compare the outcome of muscle strength with manual muscle strength testing grip and pinch strength measurements and a dynamometer which allows for measurements of the intrinsic muscles of the hand in isolation (the Rotterdam Intrinsic Hand Myometer, RIHM). METHODS: Thirty-four patients more than 2 years after ulnar and/or median nerve injury. Muscle strength was evaluated using manual muscle strength testing (MMST), grip, pinch and intrinsic muscle strength measurements. RESULTS: Manual muscle strength testing showed that most muscles recover to grade 3 or 4. Average grip strength recovery, as percentage of the uninjured hand, was 83%. Pinch strength recovery was 75%, 58% and 39% in patients with ulnar, median and combined nerve injuries, respectively. The RIHM measurements revealed a poor recovery of the ulnar nerve innervated muscles in particular (26-37%). No significant correlation (Pearson) was found between the measurements of the RIHM and grip strength. Pinch strength was significantly correlated with strength of the abduction of thumb and opposition of the thumb strength (r 0.55 and 0.72, p = 0.026, 0.002) as measured with the RIHM. CONCLUSION: While manual muscle strength testing and grip strength measurements show a reasonable to good recovery, measurements of the intrinsic muscles by means of the RIHM showed poor recovery of intrinsic muscle strength after peripheral nerve injury. No correlation was found between the recovery of intrinsic muscle strength and grip strength measurements.

Adolescent↗

PubMed2001

Reliability of stationary dynamometer muscle strength testing in community-dwelling older adults.

OBJECTIVES: To determine the 1-week test-retest reliability of stationary dynamometer scores in the measurement of muscle strength in older adults and to determine the reliability of composite scores obtained by combining right and left lower limb strength scores for each muscle group. DESIGN: In separate sessions, 1 therapist performed repeated measurements of muscle force production. SETTING: Outpatient physical therapy clinic of a large teaching hospital. PARTICIPANTS: A convenience sample of 25 volunteers aged 70 to 87 years residing independently in the community and who did not have significant health problems. INTERVENTION: On 2 separate occasions, 1 week apart, bilateral isometric force measurements were obtained for the flexor and extensor muscle groups of the ankle, knee, and hip joints. MAIN OUTCOME MEASURES: For test-retest reliability of individual and composite scores, the intraclass correlation coefficients (ICCs) and 90% confidence intervals were determined. RESULTS: The mean scores for ankle dorsiflexion, knee flexion and extension, and hip flexion exhibited excellent reliability with ICCs ranging from.90 to.76 for the individual lower limb scores and.91 to.84 for the composite scores. Scores for the remaining muscle groups exhibited good reliability with ICCs ranging from.74 to.71 for the composite scores. CONCLUSION: The stationary dynamometer is a reliable tool to use in determining lower limb muscle force production in elderly adults.

Aged↗

PubMed2006

Patterns and correlates of muscle strength loss in older women.

BACKGROUND: The aging process is associated with progressive declines in muscle strength, resulting in functional disability and reduced quality of life. OBJECTIVE: The purpose of this epidemiological study was to examine the age-related loss of grip strength both cross-sectionally and longitudinally and the risk factors associated with the decline in muscle strength in a large population of community-living older women (aged 65-91 years). METHODS: Clinical visits, including physical examinations and lifestyle assessment, were conducted at baseline and biennially afterwards for a total of 10 years of follow-up. The upper-body muscle strength was measured by grip strength using a hand-held dynamometer. RESULTS: The muscle strength decreased cross-sectionally (n = 9,372) as well as longitudinally (n = 5,214), as age increased, and the decline in muscle strength measured during follow-up was greater than that measured cross-sectionally at baseline. The average loss of grip strength during 10 years of follow-up was 5.1 kg, equivalent to a rate of 2.4% decline per year, with the greatest loss seen in the oldest age group (80 years or older). Cross-sectional analysis revealed that the correlates of lower muscle strength included older age, greater weight, greater height loss since age 25 years, lower protein intake, difficulties in functional tasks, and lower physical activity. In longitudinal analysis, older age, baseline strength, weight and height loss during follow-up, difficulties in functional tasks, and lower physical activity were found to be significantly and independently associated with greater loss in grip strength during follow-up. CONCLUSIONS: Cross-sectional and longitudinal analyses of age-related loss of muscle strength yielded different rates of decline. In addition to older age and difficulties in functional tasks, a number of modifiable factors, including weight and physical activity, are associated with increased decline in muscle strength among older women.

Age Factors↗

PubMed2006

Dynamometry of intrinsic hand muscles in patients with Charcot-Marie-Tooth disease.

BACKGROUND: Several problems are associated with manual muscle testing and dynamometry in the hands of patients with Charcot-Marie-Tooth (CMT) disease. OBJECTIVE: To evaluate the efficacy of the Rotterdam Intrinsic Hand Myometer (RIHM) to directly measure intrinsic hand muscle strength in CMT disease. METHODS: We measured hand muscle strength and hand function in 41 patients with CMT disease. RESULTS: RIHM measurement of intrinsic strength had excellent reliability. We found overlapping RIHM strength values in Medical Research Council grades 3 to 5. High grip and pinch strength could be found in patients with severe intrinsic muscle weakness. RIHM measurements were more strongly correlated with fine motor skills of the hand than grip and pinch strength. CONCLUSIONS: The Rotterdam Intrinsic Hand Myometer is a reliable instrument to measure intrinsic hand muscles strength in patients with Charcot-Marie-Tooth disease, providing more detailed information than manual muscle testing and a more direct assessment of intrinsic muscle loss than grip and pinch dynamometers.

Adolescent↗

PubMed1998

Pain and disability in patients with osteoarthritis of hip or knee: the relationship with articular, kinesiological, and psychological characteristics.

OBJECTIVE: To determine to what extent articular, kinesiological, and psychological factors each contribute to pain and disability in patients with osteoarthritis (OA), after controlling for other factors. METHODS: Cross sectional study among 200 patients with OA of the hip or knee. Dependent variables include pain (visual analog scale), self-reported disability (questionnaire), and observed disability (performance of standardized tasks). Independent variables include joint degeneration (radiographs), muscle strength (dynamometer), range of joint motion (goniometer), pain coping (behavioral and cognitive strategies), and psychological well being (depression, anxiety, cheerfulness). Multiple regression analysis was used. RESULTS: Pain was found to be associated with muscle weakness and pain coping (p < 0.05). Disability was associated with muscle weakness, range of joint motion, pain, pain coping, and psychological well being (all p < 0.05). Both pain and disability were most strongly associated with kinesiological characteristics and pain coping. CONCLUSION: After controlling for the other characteristics, kinesiological and psychological characteristics in patients with OA are each associated with disability. The association with pain is less clear. Future research on mechanisms underlying these associations is warranted.

Adult↗

PubMed2007

Influence of lever arm and stabilization on measures of hip abduction and adduction torque obtained by hand-held dynamometry.

OBJECTIVE: To examine the reliability of clinical techniques for testing hip abductor and adductor muscle performance. DESIGN: Repeated measures. SETTING: Academic laboratory. PARTICIPANTS: A sample of 21 healthy subjects (12 men, 9 women) between 22 and 31 years of age. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Reliability of repeated measures was estimated by calculating intraclass correlation coefficients. Torque production capability was calculated by multiplying force output obtained with a hand-held dynamometer by the length of the resistance lever arm. RESULTS: The reliability of abduction testing was greatest in the long-lever condition. Adduction test reliability was greatest in the long-lever condition with bench stabilization. The maximal hip abduction torque tested in the long-lever position was significantly greater (t(20)=9.21, P<.001) than that in the short-lever position. The maximal hip adduction torque occurred using a long lever for resistance application and a bench to stabilize the nontest leg (F(1,20)=15.64, P=.001). CONCLUSIONS: Muscle performance testing of hip abductors and adductors with a hand-held dynamometer can be performed with good to excellent intratester and intertester reliability. Hip abduction testing is best performed with a long lever. Hip adduction is best performed with a long lever and a bench to stabilize the nontest extremity.

Adult↗

PubMed2006

Effects of baseline serum levels of Se on markers of eccentric exercise-induced muscle injury.

Inflammation and oxidative stress have been implicated in the mechanism of eccentric exercise-induced muscle injury. This study examined whether baseline serum levels of selenium (Se), a trace element that participates in both antioxidant and anti-inflammatory systems, affects the overall response to injury. Thirteen males performed 36 maximal eccentric actions with the elbow flexors of the non-dominant arm on a motorized dynamometer. Venous blood samples were collected immediately before and after exercise at 2, 24, 48, 72 and 96 hours. Established indicators of muscle damage such as maximum isometric torque (MIT), range of motion (ROM), relaxed arm angle (RANG), flexed arm angle (FANG), arm circumference (CIRC), muscle soreness and serum levels of creatine kinase (CK) and lactate dehydrogenase (LDH) were determined at the same time points. Baseline serum levels of Se were also measured. Complementary data regarding assessment of Se status were retrieved by the use of a semi-quantitative food frequency questionnaire. All measures changed significantly (p<0.05) after exercise. The main finding of this study was that baseline Se serum levels were associated inversely with CK, LDH and FANG and positively with MIT and ROM (p<0.05). These data suggest that beyond overt Se deficiency, suboptimal Se status possibly worsens muscle functional decrements subsequent to eccentric muscle contractions.

Adult↗

PubMed2006

Mechanical and morphological properties of the triceps surae muscle-tendon unit in old and young adults and their interaction with a submaximal fatiguing contraction.

The purposes of this study were to examine (a) whether the morphological properties of the muscle gastrocnemius medialis (GM) contribute to the known enhanced muscle fatigue resistance during submaximal sustained isometric plantar flexion contraction of old compared to young adults and (b) whether a submaximal fatiguing contraction differently affects the mechanical properties of the GM tendon and aponeurosis of old and young adults. Fourteen old and 12 young male subjects performed maximal voluntary isometric plantar flexions (MVC) on a dynamometer before and after a submaximal fatiguing task (40% MVC). Moments and EMG signals from the gastrocnemius medialis and lateralis, soleus and tibialis anterior muscles were measured. The elongation of the GM tendon and aponeurosis and the morphological properties of its contractile element were examined by means of ultrasonography. The old adults showed lower maximal ankle joint moment, stiffness and fascicle length in both tested conditions. The submaximal fatiguing contraction did not affect the force-strain relationship of the GM tendon and aponeurosis of either young or old adults. The time to task failure was longer for the old adults and was strongly correlated with the fascicle length (r(2)=0.50, P<0.001). This provides evidence on that the lower ratio of the active muscle volume to muscle force for the old adults might be an additional mechanism contributing to the known age related increase in muscle fatigue resistance.

Adult↗

PubMed2006

Limiting factors of exercise performance 1 year after lung transplantation.

BACKGROUND: After lung transplantation (LTx) exercise capacity frequently remains limited, despite significantly improved pulmonary function. The aim of this study was to evaluate maximal exercise capacity and peripheral muscle force before and 1 year after LTx, and to determine whether peripheral muscle force and lactate threshold (LT) limit exercise capacity 1 year after LTx. METHODS: Twenty-five subjects (mean age 43 years, 8 women and 17 men, 4 single-lung transplantations) were included in the study. Measurements included maximal exercise capacity, lactate threshold (symptom-limited bicycle ergometer test) and muscle force test (hand-held dynamometer) were performed before and 1 year after LTx. RESULTS: Before LTx, all patients showed severe exercise intolerance (mean +/- SD): work capacity (W(peak)), 11.6 +/- 18 W; peak oxygen uptake (Vo(2)), 8.6 +/- 3.6 ml/min/kg. After LTx, exercise capacity improved significantly: W(peak), 69 +/- 27 W (p < 0.001); peak Vo(2), 15.7 +/- 4.3 ml/min/kg (p < 0.001). Ventilatory factors did not appear to limit exercise capacity. Quadriceps muscle force pre- vs post-LTx was: 248 +/- 73 N vs 281 +/- 68 N (p < 0.05). Post-LTx, a significant correlation was found between LT and exercise capacity (r = 0.76, p < 0.001), between muscle force and exercise capacity (r = 0.41, p < 0.05) and between the LT and muscle force (r = 0.53, p < 0.01). CONCLUSIONS: The occurrence of an early and pathologic LT and peripheral muscle weakness contributes to the limitation of exercise capacity and reflects a peripheral deficit post-LTx.

Adolescent↗

PubMed2007

Mechanomyographic and electromyographic responses to stimulated and voluntary contractions in the dorsiflexors of young and old men.

The effect of age on mechanomyography (MMG) has not been examined for electrically evoked contractions. Similar to torque, we expected that postactivation potentiation of the MMG would differ between young and old subjects. Additionally, under voluntary conditions, we compared normalized MMG and electromyographic (EMG) signals in relation to torque, and expected that MMG, unlike EMG, would be affected by age. In 10 young and 10 old men, electrical stimulation was delivered before and after a 10-s maximal voluntary contraction (MVC) to assess potentiation of contractile (twitch torque; Pt), electrical (M-wave amplitude), and mechanical (MMG amplitude) properties of the dorsiflexors. Subsequently, subjects performed voluntary contractions at 20%, 40%, 60%, 80%, and 100% MVC for calculation of normalized MMG-torque and EMG-torque relationships. Following the MVC, Pt and evoked MMG were larger than at rest in both groups, but M-wave amplitude was unchanged. Twitch potentiation was greater in young than old, whereas evoked MMG was unaffected by age. Under voluntary conditions, values for MMG and EMG were similar between groups, except for greater MMG at MVC in young men. The shape of MMG and EMG relationships to torque was similar only in young men. Using the aging model, our results indicate that potentiation of the mechanical components (MMG) differ from those of twitch torque. Furthermore, the comparison of normalized voluntary MMG with age provides additional support for the concept of age-related motor unit remodeling.

Action Potentials↗

PubMed2007

The effect of eccentric exercise on position sense and joint reaction angle of the lower limbs.

Impaired position sense and impaired joint reaction angle of the lower limbs after muscle-damaging activities is a serious functional limitation that may lead to an increased risk of injury, particularly in older populations. The purpose of the present study was to examine whether position sense and joint reaction angle to release can be affected by eccentric exercise-induced muscle damage. Twelve women underwent an isokinetic exercise session of the lower limb. Isometric peak torque, delayed-onset muscle soreness, serum creatine kinase, position sense, and knee joint reaction angle to release were examined before, immediately after, and 24, 48, and 72 h post-exercise. Due to the effect of eccentric exercise, subjects persistently placed their lower limb at a more extended position, representing a shorter knee extensor muscle. Eccentric exercise increased the knee reaction angle of the lower limb after release from 0 degrees and 15 degrees but not from 30 degrees and 45 degrees . Position sense and joint reaction to release were similarly affected by eccentric exercise and independently of visual feedback. Position sense was impaired only immediately post-exercise (probably due to muscle fatigue), whereas impairment of the reaction angle to release persisted up to 3 days post-exercise (probably due to muscle damage). Attenuation of position sense and joint reaction angle of the lower limbs after damaging activities is a serious functional limitation that may lead to an increase risk of injury, particularly in older populations.

Adult↗

PubMed2006

Adjustments of prehension synergies in response to self-triggered and experimenter-triggered load and torque perturbations.

Humans are known to show anticipatory adjustments in the grip force prior to a self-generated or predictable action or perturbation applied to a hand-held object. We investigated whether humans can also adjust covariation of individual finger forces (multi-finger synergies) prior to self-triggered perturbations. To address this issue, we studied adjustments in multi-digit synergies associated with applied load/torque perturbations while the subjects held a customized handle steadily. The main hypothesis was that the subjects would be able to demonstrate the phenomenon of anticipatory covariation, that is changes in covariation patterns among digit forces and moments of force in anticipation of a perturbation, but only when the perturbation was triggered by the subjects themselves. Based on the principle of superposition (decoupled grasping force and resultant torque control), we also expected to see different adjustments in indices of multi-digit synergies stabilizing the total gripping force and the total moment of force. The task for the subjects (n = 8) was to return the initial handle position as quickly as possible after a perturbation, which consisted of removing one of three loads hanging from the handle. There were six experimental conditions: two types of perturbations (self-triggered and experimenter-triggered) by three positions of the load (left, center, and right). Three-dimensional forces and moments of force recorded from each digit contact were used for the analysis. Indices of covariation among digit forces and among moments of force, previously employed for studying motor synergies, were computed across trials. Positive values of the indices reflected negative covariations of individual digit forces and moments of force (their inter-compensatory changes) to stabilize the total force and moment acting on the handle. In steady-state conditions, subjects showed strong positive indices for both digit forces and digit moments. Under the self-triggered conditions, changes in the indices of digit force and moment covariation were seen about 150 ms prior to the perturbation, while such changes were observed only after the perturbation under the experimenter-triggered conditions. Immediately following a perturbation, the indices of force and moment covariation rapidly changed to negative revealing the lack of inter-compensation among the individual digit forces and moments. Later, both indices showed a recovery to positive values; the recovery was faster in the self-triggered conditions than in the experimenter-triggered ones. During the steady-state phase after the perturbation, the indices of force and moment covariation decreased and increased, respectively, as compared to their values during the steady-state phase prior to the perturbation. We conclude that humans are able to adjust multi-digit synergies involved in prehensile tasks in anticipation of a self-triggered perturbation. These conclusions speak against hypotheses on the organization of multi-element actions based on optimal control principles. Different changes in the indices of force and moment covariation after a perturbation corroborate the principle of superposition. We discuss relations of anticipatory covariation to anticipatory postural adjustments.

Adult↗

PubMed2006

Development of a position-specific index of muscle strength to be used in stroke evaluation.

OBJECTIVE: To develop a position-specific index of muscle strength for individuals with stroke. DESIGN: Cross-sectional design. SETTING: A major teaching hospital in a Canadian urban city. PARTICIPANTS: Sixty-three patients with poststroke onset between 3 and 12 months. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: The muscle strength of the lower-extremity muscles was tested bilaterally in multiple positions using hand-held dynamometry. RESULTS: A principal components analysis resulted in grouping the muscles of the affected and unaffected sides of the gravity related and gravity eliminated positions into 5 indices. The 5 indices were moderately to highly correlated (r2 range, .59-.81) with each other and so were combined into 1 global index. The gravity related muscle strength on the affected side was, on average, 85% of the unaffected side (range, 37%-157%); the gravity eliminated muscle strength of the affected side was, on average, 92% of the unaffected side (range, 53%-121%). CONCLUSIONS: This study resolves the methodologic issue of how to summarize multiple data points that relate to one construct, namely, strength of different muscle groups assessed in several positions.

Aged↗

PubMed2006

Evaluation of spastic muscle in stroke survivors using magnetic resonance imaging and resistance to passive motion.

OBJECTIVE: To assess the feasibility of using magnetic resonance imaging (MRI) and resistance to passive movement to evaluate spastic muscle. DESIGN: T2-weighted MRI scans of the upper arm were obtained at rest and after the performance of upper-arm exercise. In addition, resistance to passive movement was measured subjectively (Modified Ashworth Scale [MAS]) and objectively by an isokinetic device while the arm was moved at varying speeds (stretch reflex torque). SETTING: Research laboratory. PARTICIPANTS: Six hemiplegic stroke survivors (single group) with spasticity in the elbow flexors and extensors. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Strength, stretch reflex torque, MAS, MRI-derived muscle cross-sectional area (CSA), and transverse relaxation time (T2). RESULTS: The affected sides exhibited spasticity (as assessed through MAS), with the extensors displaying a range of 0 to 3, and the flexors between 1 and 1+. The affected muscle groups were significantly weaker than the unaffected muscle groups (extensors: 61% less, flexors: 65% less; P< or =.05). The affected CSA of the triceps was 25% smaller than that of the unaffected side (P=.01), but the biceps muscle group was similar (5% less on the affected side, P> or =.05). There was a tendency (P=.07; effect size, .48) for the resting T2 to be higher in affected versus unaffected biceps, but triceps values were similar (P> or =.05). Both muscle groups showed an increase in T2 after exercise ( approximately 30%, P< or =.05); however, the affected sides did not show an increase (P> or =.05). For both muscle groups, the affected side had a greater stretch reflex torque, with the range of torque values being greater than the range of MAS scores. CONCLUSIONS: MRI and quantitative resistance to passive movement may be useful in the evaluation of spasticity. This is clinically relevant for the development and evaluation of antispasticity treatments.

Arm↗

PubMed2006

The effects of muscle damage following eccentric exercise on gait biomechanics.

To examine the effects of knee extensors muscle damage on walking and running biomechanics in healthy males. Muscle damage was caused by 60 (6x10) maximal eccentric knee flexions of both legs, selected in a random order, at an angular velocity of 1.05rad/s in 10 volunteers (mean age 20+/-1.0 years). Muscle damage indicators (creatine kinase (CK), lactate dehydrogenase (LDH), delayed onset muscle soreness (DOMS), eccentric and isometric (110 degrees knee flexion) peak torque), pelvic three dimensional (3D) orientation, as well as hip, knee and ankle-joint flexion/extension angles during gait (walking at 1.2m/s and running at 2.8m/s) were assessed pre- and 48h post-eccentric exercise. All muscle damage indicators revealed significant changes post- compared to pre-exercise data (P<0.05) confirming that muscle damage did occur. Kinematic analysis revealed that muscle damage significantly decreased the knee-joint angle range of movement at the stance and swing phases during walking (P<0.05) and running (P<0.05), respectively. These changes were accompanied by corresponding increases of pelvic rotation (P<0.05) and decrease of pelvic tilt (P<0.05). The present data demonstrate that damage of knee extensors result in changes of treadmill walking and running kinematics at both knee joint and pelvis. The fact that these alterations occur at different gait phases could be attributed to the speed of movement and to a self-protection mechanism to prevent further damage.

Adult↗

PubMed2006

Agonist and antagonist muscle activation during maximal and submaximal isokinetic fatigue tests of the knee extensors.

The purpose of this study was to examine the differences in electromyographic activity of agonist and antagonist knee musculature between a maximal and a submaximal isokinetic fatigue protocol. Fourteen healthy males (age: 24.3+/-2.5 years) performed 25 maximal (MIFP) and 60 submaximal (SIFP) isokinetic concentric efforts of the knee extensors at 60 degrees s(-1), across a 90 degrees range of motion. The two protocols were performed a week apart. The EMG activity of vastus medialis (VM), vastus lateralis (VL) and biceps femoris (BF) were recorded using surface electrodes. The peak torque (PT) and average EMG (aEMG) were expressed as percentages of pre-fatigue maximal value. One-way analysis of variance indicated a significant (p<0.05) decline of PT during the maximal (45.7%) and submaximal (46.8%) protocols. During the maximal test, the VM and VL aEMG initially increased and then decreased. In contrast, VM and VL aEMG continuously increased during submaximal testing (p<0.05). The antagonist (BF) aEMG remained constant during maximal test but it increased significantly and then declined during the submaximal testing. The above results indicate that agonist and antagonist activity depends on the intensity of the selected isokinetic fatigue test.

Adult↗

PubMed2006

Muscular utilization of the plantarflexors, hip flexors and extensors in persons with hemiparesis walking at self-selected and maximal speeds.

Gait performance secondary to a stroke is partially dependent on residual muscle strength. However, to pinpoint more precisely the mechanism of this relationship, biomechanical models, such as the muscular utilization ratio (MUR) that integrates both muscle strength and gait parameters into the concept of level of effort, are warranted. The aim of the present study was to evaluate the MUR of plantarflexors, hip flexors and extensor muscles during their concentric action in 17 chronic hemiparetic participants walking at self-selected and maximal speeds. Results revealed that peak MUR increased with gait speed. At self-selected speed (0.73+/-0.27 m/s), peak MUR values on the paretic side were 64% (+/-18.7), 46% (+/-27.6) and 33% (+/-25.6) for the plantarflexors, hip flexors and extensor muscles, respectively. At maximal speed (1.26+/-0.39 m/s), corresponding values were 77% (+/-23.6), 72% (+/-33.0) and 58% (+/-32.1). Peak MUR showed negative associations (-0.33 -0.68), although not all significant, with voluntary muscle strength. The results of this study indicated that the peak MUR increased with gait speed. The plantarflexors were the most used muscle group at self-selected speed, whereas at maximal speed the three muscle groups showed similar peak MUR values. This last finding suggested an important role of the hip muscles in reaching a faster speed. Lastly, because moderate associations were found between peak MUR values and the voluntary muscle strength of hip flexors and extensors, it can be concluded that the weakest paretic muscle groups show, in general, the highest level of effort during gait.

Acceleration↗

PubMed2007

Resistance training and locomotor recovery after incomplete spinal cord injury: a case series.

STUDY DESIGN: Longitudinal intervention case series. OBJECTIVE: To determine if a 12-week resistance and plyometric training program results in improved muscle function and locomotor speed after incomplete spinal cord injury (SCI). SETTING: University research setting. METHODS: Three ambulatory individuals with chronic (18.7+/-2.2 months post injury) motor incomplete SCI completed 12 weeks of lower extremity resistance training combined with plyometric training (RPT). Muscle maximum cross-sectional area (max-CSA) of the knee extensor (KE) and plantar flexor (PF) muscle groups was determined using magnetic resonance imaging (MRI). In addition, peak isometric torque, time to peak torque (T (20-80)), torque developed within the initial 220 ms of contraction (torque(220)) and average rate of torque development (ARTD) were calculated as indices of muscle function. Maximal as well as self-selected gait speeds were determined pre- and post-RPT during which the spatio-temporal characteristics, kinematics and kinetics of gait were measured. RESULTS: RPT resulted in improved peak torque production in the KE (28.9+/-4.4%) and PF (35.0+/-9.1%) muscle groups, as well as a decrease in T(20-80), an increased torque(220) and an increase ARTD in both muscle groups. In addition, an increase in self-selected (pre-RPT=0.77 m/s; post-RPT=1.03 m/s) and maximum (pre-RPT=1.08 m/s; post-RPT=1.47 m/s) gait speed was realized. Increased gait speeds were accompanied by bilateral increases in propulsion and hip excursion as well as increased lower extremity joint powers. CONCLUSIONS: The combination of lower extremity RPT can attenuate existing neuromuscular impairments and improve gait speed in persons after incomplete SCI.

Adolescent↗