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At least 1,315 records · Page 73Linked to original sources
PubMed1997

Acute effects of oral glibenclamide on blood pressure and forearm vascular resistance in diabetics.

1. To determine the effects of an acute oral dose of glibenclamide on blood pressure (BP), basal forearm vascular resistance (FVR) and FVR responses to the K+ATP channel activating vasodilator diazoxide, a placebo-controlled, double-blind cross-over study was performed in eight male volunteers with non-insulin-dependent diabetes mellitus. 2. Changes in vascular responses to progressively increasing concentrations of diazoxide (3.75-30 mg/kg per min) and noradrenaline (25-100 ng/kg per min) were measured by venous occlusion plethysmography. 3. Glibenclamide significantly lowered plasma glucose levels compared with placebo (P < 0.02) and attenuated the decrease in FVR (P < 0.05) and the decrease in systolic BP (P < 0.05) that followed a meal. However, vasodilator responses to diazoxide were potentiated by the administration of oral glibenclamide (P < 0.01). 4. Acute administration of oral glibenclamide attenuates the normal decrease in FVR and systolic BP that follows a meal and potentiates rather than inhibits forearm vasodilator responses to intra-arterial diazoxide, probably via indirect humoral effects. These results suggest that glibenclamide has direct or indirect vasoconstrictor effects that antagonize the normal increase in forearm blood flow that follows a meal and that the inhibition of vascular K+ATP channels following acute oral glibenclamide administration is clinically insignificant compared with other indirect vascular effects of the drug.

Adenosine Triphosphate↗
PubMed1998

Acute effects of oral glibenclamide on blood pressure and forearm vascular resistance in diabetics.

1. To determine the effects of an acute oral dose of glibenclamide on blood pressure (BP), basal forearm vascular resistance (FVR) and FVR responses to the K+(ATP) channel activating vasodilator diazoxide, a placebo-controlled, double-blind cross-over study was performed in eight male volunteers with non-insulin-dependent diabetes mellitus. 2. Changes in vascular responses to progressively increasing concentrations of diazoxide (3.75-30 mg/kg per min) and noradrenaline (25-100 ng/kg per min) were measured by venous occlusion plethysmography. 3. Glibenclamide significantly lowered plasma glucose levels compared with placebo (P < 0.02) and attenuated the decrease in FVR (P < 0.05) and the decrease in systolic BP (P < 0.05) that followed a meal. However, vasodilator responses to diazoxide were potentiated by the administration of oral glibenclamide (P < 0.01). 4. Acute administration of oral glibenclamide attenuates the normal decrease in FVR and systolic BP that follows a meal and potentiates rather than inhibits forearm vasodilator responses to intra-arterial diazoxide, probably via indirect humoral effects. These results suggest that glibenclamide has direct or indirect vasoconstrictor effects that antagonize the normal increase in forearm blood flow that follows a meal and that the inhibition of vascular K+(ATP) channels following acute oral glibenclamide administration is clinically insignificant compared with other indirect vascular effects of the drug.

Adult↗
PubMed1989

Replantation of an excised segment of radial forearm tissue.

A report on a case of successful replantation of an excised segment of forearm tissue is presented. An 18 year old man was admitted to hospital with a completely excised segment of the radial side of his forearm and wrist as a result of a circular saw injury. The best reconstructive option was replantation of the excised radial forearm tissue thus providing both soft tissue cover and bony stabilization.

Accidents, Occupational↗
PubMed2006

Forearm vascular response to nitric oxide and calcitonin gene-related peptide: comparison between migraine patients and control subjects.

The forearm vascular response to nitric oxide (NO) and calcitonin gene-related peptide (CGRP) was investigated in 10 migraine patients and 10 matched control subjects. Changes in forearm blood flow (FBF) during intrabrachial infusion of: (i) serotonin (releasing endogenous NO), (ii) sodium nitroprusside (SNP, exogenous NO-donor), and (iii) CGRP were measured using venous occlusion plethysmography. Flow-mediated dilation (FMD) of the brachial artery, a measure for the endogenous release of NO reactive to occlusion, was measured using ultrasound and expressed as percentage change vs. baseline diameter. FBF ratio (i.e. FBF in the infused over the control arm) at baseline (1.1 +/- 0.1) did not differ between both populations. Serotonin, SNP and CGRP induced a dose-dependent increase (P < 0.001) in FBF ratio in controls (to 2.8 +/- 0.3, 6.7 +/- 1.4 and 6.9 +/- 1.2 at the highest dose, respectively) and migraineurs (2.5 +/- 0.4, 5.6 +/- 0.8 and 6.5 +/- 1.3, respectively); these ratios did not differ between both groups. FMD was comparable in control subjects (5.8 +/- 1%) and migraine patients (5.2 +/- 1%). Based on the forearm vascular response to NO and CGRP, migraine patients do not display generalized changes in vascular function.

Adult↗
PubMed1998

Role of spinal premotoneurones in mediating corticospinal input to forearm motoneurones in man.

1. Evidence was sought to support the suggestion that corticospinal input can be relayed to motoneurones (MNs) via a population of interneurones (premotoneurones) in the cervical cord, and that this pathway operates in parallel with the direct monosynaptic pathway. 2. Single motor units were recorded in forearm muscles and post-stimulus time histograms (PSTHs) of their firing pattern were constructed during voluntary activation. Weak transcranial magnetic stimulation of the contralateral motor cortex was used to produce a small facilitation in the PSTH. We then examined how the size of this peak was affected by low threshold electrical stimulation of either the homonymous muscle nerve or the musculo-cutaneous nerve at various interstimulus intervals (ISIs). 3. Homonymous nerve stimulation had the following characteristics: (a) the cortical peak was facilitated when stimuli were timed so that both inputs arrived simultaneously at the MN; (b) the amount of facilitation was only slightly greater than the sum of the effects of each stimulus given alone; and (c) facilitation affected even the earliest bins of the cortically evoked peak. These three features are consistent with a monosynaptic input onto the MN from both sources. 4. Stimulation of the musculo-cutaneous nerve (which has no monosynaptic connections with forearm MNs) had no effect at similar timings. It (a) produced facilitation only at longer intervals corresponding to an extra central delay of 4-6 ms; (b) always gave a significantly larger facilitation than expected from the algebraic sum of the effects of each stimulus given alone; and (c) never affected the earliest bins of the cortical peak. These features are compatible with interaction of peripheral and cortical inputs at a population of premotoneurones. 5. These results confirm the suggestion that premotoneurones mediate part of the cortical command to MNs innervating forearm muscles. 6. Excitation is followed by an inhibition which may almost completely suppress the cortical peak. It is suggested that cortical and musculo-cutaneous volleys also converge onto inhibitory interneurones projecting to the premotoneuronal pool.

Adult↗
PubMed1998

Detection of movements of the human forearm during and after co-contractions of muscles acting at the elbow joint.

1. We report here observations on the effects of muscle contraction history on thresholds for the detection of movements at the elbow joint of human subjects. Detection thresholds were measured in the direction of flexion or extension to movements of the relaxed forearm at a speed of 0.2 deg s-1 with the elbow at 90 deg. 2. As reported previously, thresholds for movements in the direction of extension were lower than in the direction of flexion after a conditioning co-contraction of elbow muscles with the arm flexed by 30 deg from its mid-position (hold-short). After a co-contraction with the arm held extended by 30 deg (hold-long), thresholds were lower in the direction of flexion. 3. Here we have made two additional observations. Thresholds for movements of the passive forearm after a co-contraction at the 90 deg test position (hold-test) were low, both in the direction of flexion and extension. Secondly, when thresholds were measured while subjects were carrying out a co-contraction of forearm muscles (15-20 % maximum voluntary contraction), thresholds were much higher. 4. It is concluded that muscle contraction history is an important factor to consider when making measurements of movement thresholds at the relaxed elbow joint. It is speculated that during an active contraction increases in muscle spindle discharges evoked by fusimotor activity lead to the rise in movement detection threshold.

Adult↗
PubMed2000

Monosynaptic Ia projections from intrinsic hand muscles to forearm motoneurones in humans.

Heteronymous Ia excitatory projections from intrinsic hand muscles to human forearm motoneurones (MNs) were investigated. Changes in firing probability of single motor units (MUs) in the flexor carpi radialis (FCR), flexor carpi ulnaris (FCU), flexor digitorum superficialis (FDS), extensor carpi radialis (ECR), extensor carpi ulnaris (ECU) and extensor digitorum communis (EDC) were studied after electrical stimuli were applied to the median and ulnar nerve at wrist level and to the corresponding homonymous nerve at elbow level. Homonymous facilitation, occurring at the same latency as the H reflex, and therefore attributed to monosynaptic Ia EPSPs, was found in all the sampled units. In many MUs an early facilitation was also evoked by heteronymous low-threshold afferents from intrinsic hand muscles. The low threshold (between 0.5 and 0.6 times motor threshold (MT)) and the inability of a pure cutaneous stimulation to reproduce this effect indicate that it is due to stimulation of group I muscle afferents. Evidence for a similar central delay (monosynaptic) in heteronymous as in homonymous pathways was accepted when the difference in latencies of the homonymous and heteronymous peaks did not differ from the estimated supplementary afferent conduction time from wrist to elbow level by more than 0.5 ms (conduction velocity in the fastest Ia afferents between wrist and elbow levels being equal to 69 m s-1). A statistically significant heteronymous monosynaptic Ia excitation from intrinsic hand muscles supplied by both median and ulnar nerves was found in MUs belonging to all forearm motor nuclei tested (although not in ECU MUs after ulnar stimulation). It was, however, more often found in flexors than in extensors, in wrist than in finger muscles and in muscles operating in the radial than in the ulnar side. It is argued that the connections of Ia afferents from intrinsic hand muscles to forearm MNs, which are stronger and more widely distributed than in the cat, might be used to provide a support to the hand during manipulatory movements.

Adult↗
PubMed1989

Plasma concentrations of adrenaline, noradrenaline and dopamine during forearm dynamic exercise.

In six healthy volunteers plasma concentrations of adrenaline, noradrenaline and dopamine were measured at rest and during dynamic forearm exercise at submaximal and maximal intensities. Arterial and venous concentrations of adrenaline and noradrenaline increased with forearm exercise at all workloads. Dopamine concentrations did not change. The increases in adrenaline and noradrenaline were almost linearly related to the increase in heart rate with no levelling off at maximal exercise intensities. It is concluded that dynamic exercise with the forearm muscle group causes a small but significant activation of the sympatho-adrenal system as reflected by increases in plasma concentrations of adrenaline and noradrenaline.

Adult↗
PubMed1990

The effect of calcitonin gene-related peptide (CGRP) on human forearm blood flow.

The effect of intravenous and intra-arterially administered calcitonin gene-related peptide (CGRP) on the human forearm blood flow and cutaneous blood flow were investigated by means of venous occlusion plethysmography and laser-Doppler flowmetry, respectively. Infusion of CGRP (11-216 pmol min-1) into the brachial artery resulted in a dose-dependent increase in forearm blood flow and cutaneous blood flow which persisted for up to 90 min after the infusion was stopped. Repeated infusions resulted in an identical response. Systemic intravenous infusion of CGRP (104-520 pmol min-1) resulted in a dose-dependent flush in the face, neck, upper trunck and upper arms, and an increase in the forearm blood flow. The cutaneous blood flow was dramatically increased on the forehead, whereas on the hand only a slight increase was noted. By intravenous infusions a significant drop in blood pressure and increase in heart rate were seen at 520 pmol min-1. Thus, it is possible to give CGRP in doses that increase the blood flow in muscle and skin without resulting in a fall in systemic arterial blood pressure and tachycardia, suggesting that CGRP may be used as a tool for the treatment of various conditions in man with compromised blood flow.

Adolescent↗
PubMed1995

Phosphoramidon inhibition of the in vivo conversion of big endothelin-1 to endothelin-1 in the human forearm.

1. The vasoconstrictor peptide, endothelin-1 (ET-1) and a biologically inactive C-terminal fragment (CTF) are generated from an intermediate big ET-1 by a putative ET converting enzyme, sensitive to phosphoramidon. We have developed a procedure using selective solid-phase extraction and specific radioimmunoassays to measure the levels of immunoreactive (IR) big ET-1 and the products of conversion (ET-1 and CTF) in human plasma. These techniques have been used to determine the levels of the three peptides in venous plasma following local infusions of ET-1 and big ET-1, both alone and together with phosphoramidon. 2. Infusion of ET-1 into the brachial artery (5 pmol min-1) significantly increased (P < 0.05) IR ET levels from a basal level of 2.3 pM to 55.2 pM in plasma from the infused arm after 60 min of infusion. This corresponded with a marked decrease in forearm blood flow from a basal level of 2.6 ml dl-1 min-1 to 1.7 ml dl-1 min-1. The levels of IR big ET-1 and CTF were unchanged. Co-infusion of phosphoramidon (30 nmol min-1) with ET-1 had no significant effect on the plasma IR levels of ET, big ET-1, CTF, or blood flow. 3. Big ET-1 (50 pmol min-1) significantly increased (P < 0.05) venous concentrations of all three IR peptides after 60 min compared to basal (ET: from 2.2 to 7.7 pM, big ET-1; from 0 to 386.0 pM, CTF: from 0.2 to 37.0 pM). Forearm blood flow decreased significantly (P<0.05) from a basal level of 3.0 ml dl-1 min-1 to 1.6 ml dl-1 min-1.4. When phosphoramidon was co-infused with big ET-1, both the rise in IR ET and associated vasoconstriction were abolished. However, IR CTF was still detected, suggesting that either some conversion by phosphoramidon-insensitive enzyme(s) was occurring, and/or that CTF was being protected from further degradation by phosphoramidon.5. These data show that in the human forearm the activity of a phosphoramidon-sensitive ET converting enzyme is at least in part responsible for the vasoconstrictor properties of exogenous big ET-1. Furthermore, because measurable levels of newly synthesized ET-1 are likely to be rapidly reduced in the blood/plasma through receptor binding, assay of IR big ET-1 and CTF may be a more sensitive measure of ET-1 generation in disease.

Adult↗
PubMed1980

Effect of age on glucose utilization and responsiveness to insulin in forearm muscle.

To determine the effect of age on responsiveness to insulin, 35 healthy subjects (age range, 22--73 years) were studied. A glucose-clamp technique was used to obtain a range of values for steady-state arterial glucose and arterial insulin concentrations; total body glucose utilization was estimated from the rate of glucose infusion needed to maintain the steady state; and the uptake of glucose and insulin by forearm muscle was determined by a forearm perfusion procedure. The results were examined by multiple regression analyses. The rate of glucose utilization by the whole body as well as by forearm muscle was dependent upon the insulin concentration. Age had no apparent effect on body glucose utilization, the uptake of glucose or insulin by muscle, or the steady-state insulin concentration in response to hyperglycemia. It is concluded that the abnormal glucose tolerance commonly associated with increased age is not due to a decrease in either insulin secretion or insulin stimulation of glucose uptake.

Adult↗
PubMed1997

Evaluation of ketorolac in children with forearm fractures.

OBJECTIVES: To evaluate ketorolac for pain relief and an opioid-sparing effect in children with forearm fractures necessitating reduction. METHODS: A prospective, randomized, double-blind study was conducted at an urban children's hospital ED. A convenience sample of children aged 3-18 years with isolated forearm fractures was studied. None received prior pain medication. A 10-point visual analog scale (VAS) was used to assess pain at the time of study entry and prior to sedation/analgesia. The Children's Hospital of Eastern Ontario's Pain Score (CHEOPS), a 13-point behavioral score, was used to assess pain during sedation. Patients received either IV ketorolac (K), 1 mg/kg, or saline (S) after entry into the study. After a minimum of 20 minutes, pain was reassessed and supplemental analgesia/sedation administered. A standard dose of midazolam, 0.1 mg/kg to a maximum of 6 mg, was given to all patients, and fentanyl was titrated at 1-microgram/kg increments based on patient need. Once the patient was comfortable, reduction was performed and a reduction CHEOPS score assigned. RESULTS: For the 34 study children (17 K, 17 S), there was no difference in sex or mean age between the groups. Mean total doses of fentanyl were 2.26 micrograms/kg in the K group and 2.85 micrograms/kg in the S group (p = 0.07). The median changes in VAS score before and after receiving the study drug were -1.13 K and -0.18 S (p = 0.06). The median CHEOPS score was 10 for both groups. Seven of the 17 patients in the S group required the maximum fentanyl dose (4 micrograms/kg), compared with 2 of 17 in the K group (p = p.06). CONCLUSIONS: Although ketorolac seems to add to patient comfort in children with forearm fractures, it does not have a significant opioid-sparing effect. Ketorolac showed a trend toward pain relief, but statistical significance was not reached.

Adolescent↗
PubMed1979

Human forearm and kidney conversion of arachidonic acid to prostaglandins.

The capacity of the human forearm and kidney to synthetize different prostaglandins (PGs) was studied, together with the quantitative relationship between the various PGs formed in these organs. 14C-labelled arachidonic acid (14C-AA) was infused in healthy male volunteers at a constant rate into the brachial or the renal artery, with simultaneous sampling of regional venous blood. The venous plasma content of 14C-PGs was extracted, separated with thin-layer chromatography (TLC) and quantified using fractionated liquid scintillation spectrometry. Most of the 14C-AA infused was metabolized and radiopeaks parallel to unlabelled standards of PGD2, PGE2, PGF2 alpha, 6-keto-PGF1 alpha and 13,14-dihydro-15-keto-PGE2 (Me) were obtained. The chromatograms of both the forearm and the kidney plasma contained all the peaks described, but the relative distribution of the 14C-PGs differed between the two tissues. In the cubital venous plasma, the main PG (apart from Me) was 6-keto-PGF1 alpha, indicating a considerable synthesis of PGI2 in the forearm. In the renal venous plasma, on the other hand, PGD2 accounted for the largest part of the authentic 14C-PGs found. Besides the tissue differences, large inter-individual variations were observed. The results demonstrate the existence of both a considerable tissue specificity and an appreciable inter-individual variation in the local conversion of AA to PGs in man.

Adult↗
PubMed1992

Changes in muscle sympathetic nerve activity and calf blood flow during combined leg and forearm exercise.

In order to examine efferent sympathetic nerve control of the peripheral circulation during exercise, muscle sympathetic nerve activity (MSNA), calf blood flow (CBF), heart rate (HR), blood pressure (BP) and oxygen uptake were measured during combined foot and forearm exercise. An initial period of rhythmic foot exercise (RFE) (60 min-1 at 10% of maximal voluntary contraction (MVC) was followed by the addition of rhythmic handgrip exercise (RFE + OCCL) (60 min at 30% of MVC) and by forearm ischaemia after handgrip exercise while continuing RFE (RFE + OCCL). During RFE, CBF in the working leg, HR and oxygen increased respectively by 560%, 121% and 144% when compared with the control rest period, but MSNA (burst rate) was reduced by 13% (P > 0.05) and BP was unchanged. During RFE + RHG, HR, BP and oxygen uptake were greater than during RFE alone. There was no change in CBF, but a significant increase occurred in calf vascular resistance (CVR) and MSNA increased to 121% of the control level. During RFE + OCCL, MSNA, CVR and BP were all higher than during RFE alone, whereas HR and oxygen uptake decreased slightly, although they remained higher than the control values. The increase in CVR in the working leg and the rise in BP during RFE + RHG or RFE + OCCL might be linked to enhancement of MSNA, which may have been reflexly evoked by input from muscle metabolic receptors in the working forearm.

Adult↗
PubMed2006

Forearm plethysmography in the assessment of vascular tone and resistance vasculature design: new methodological insights.

AIM: High peripheral resistance and structural alteration in resistance arteries are central phenomena in essential hypertension and have been widely examined by forearm venous occlusion plethysmography; at rest for studying vascular tone, and during reactive hyperaemia for studying vascular structure. This work concerns the influence of venous pressure on hyperaemic vascular resistance (Rmin), the reproducibility of hyperaemic and resting vascular resistances (Rrest) and the relation between forearm and total peripheral vascular resistance (TPR). METHODS: In four healthy subjects, intravenous and intra-arterial blood pressures were measured simultaneously with plethysmographic recordings of hyperaemic and resting forearm blood flows. Reproducibility was examined in 15 young and 14 middle-aged healthy subjects and in 21 untreated hypertensive patients. RESULTS: Rmin remained low in the first recorded cardiac cycle, but rose in the second, even though corrected for the venous pressure rise, suggesting vascular tone recovery along with venous congestion. Between-day reproducibility of Rmin was high in middle-aged normotensive (8.7%) and hypertensive subjects (10.6%), but Rmin fell significantly between successive days in the young subjects. Rrest correlated with TPR, but required up to 40 min to reach steady state and showed high day-to-day variation in young (21.8%) and hypertensive subjects (16.2%). CONCLUSIONS: During hyperaemia, vascular resistance should be measured in the first cardiac cycle following venous occlusion to minimize influences of venous pressure rise and possible tone recovery. Rrest seems to reflect TPR. About 20 subjects may be needed to detect 15% changes between days in Rrest, fewer when concerning Rmin and TPR.

Adult↗
PubMed1966

The effect of beta adrenergic receptor blockade on the vasodilator response in the forearm to voluntary hyperventilation.

1. Blood flow was simultaneously measured by venous-occlusion plethysmography in both forearms of ten healthy men. 2. Voluntary overbreathing to produce about 8 times the resting ventilation caused a vasodilatation similar in both forearms. 3. When one forearm was treated with an intra-arterialinfusion of propranolol, a beta adrenergic blocking agent, the vasodilator response was reduced by an average of 28%, the reduction was significant (P < 0-01). 4. The failure of propranolol to abolish the vasodilator response was not due to incomplete block of beta adrenergic receptors since the dose of propranolol used reversed the vasodilator response to an intravenous infusion of adrenaline. 5. The results suggest that the vasodilator response to voluntary hyperventilation can be explained partly, but not entirely, by the release to the circulation of an adrenaline-like substance.

Adrenergic beta-Antagonists↗
PubMed2005

Impaired modulation of sympathetic alpha-adrenergic vasoconstriction in contracting forearm muscle of ageing men.

Recent evidence indicates that older healthy humans demonstrate greater vasoconstrictor tone in their active muscles during exercise compared with young adults. Therefore, we tested the hypothesis that the normal ability of muscle contractions to blunt sympathetic alpha-adrenergic vasoconstriction (functional sympatholysis) is impaired with age in healthy humans. We measured forearm blood flow (FBF; Doppler ultrasound) and calculated the forearm vascular conductance (FVC) responses to alpha-adrenergic receptor stimulation during rhythmic handgrip exercise (15% maximum voluntary contraction) and during a control non-exercise vasodilator condition (intra-arterial adenosine infusion) in seven young (25 +/- 2 years) and eight healthy older men (65 +/- 2 year). FVC responses to intra-arterial tyramine (evokes endogenous noradrenaline release), phenylephrine (alpha1-agonist) and clonidine (alpha2-agonist) were assessed. In young men, the vasoconstrictor responses to tyramine (-25 +/- 1 versus -56 +/- 6%), phenylephrine (-11 +/- 4 versus -39 +/- 4%) and clonidine (-12 +/- 4 versus -38 +/- 5%; all P < 0.005) were blunted during exercise compared with adenosine. In contrast, exercise did not significantly blunt the response to tyramine (-30 +/- 2 versus -36 +/- 7%; P = 0.4) or phenylephrine (-16 +/- 2 versus -19 +/- 3%; P = 0.3) in older men, but did attenuate the response to clonidine (-22 +/- 3 versus -37 +/- 6%; P < 0.05). The magnitude of functional sympatholysis, calculated as the difference in the vasoconstrictor responses during adenosine infusion and exercise, was significantly lower in older compared with young men in the presence of tyramine (-6 +/- 7 versus -31 +/- 6%), phenylephrine (-3 +/- 3 versus -28 +/- 4%) and clonidine (-15 +/- 4 versus -26 +/- 3%; all P < 0.05). We conclude that ageing is associated with impaired functional sympatholysis in the vascular beds of contracting forearm muscle in healthy men. These findings might help explain the greater skeletal muscle vasoconstrictor tone and reduced blood flow during large muscle dynamic exercise in older adults.

Adenosine↗
PubMed1999

Identification of time-varying stiffness, damping, and equilibrium position in human forearm movements.

Knowledge of how stiffness, damping, and the equilibrium position of specific limbs change during voluntary motion is important for understanding basic strategies of neuromotor control. Presented here is an algorithm for identifying time-dependent changes in joint stiffness, damping, and equilibrium position of the human forearm. The procedure requires data from only a single trial. The method relies neither on an analysis of the resonant frequency of the arm nor on the presence of an external bias force. Its validity was tested with a simulated forward model of the human forearm. Using the parameter estimations as forward model input, the angular kinematics (model output) were reconstructed and compared to the empirically measured data. Identification of mechanical impedance is based on a least-squares solution of the model equation. As a regularization technique and to improve the temporal resolution of the identification process, a moving temporal window with a variable width was imposed. The method's performance was tested by (a) identifying a priori known hypothetical time-series of stiffness, damping, and equilibrium position, and (b) determining impedance parameters from recorded single-joint forearm movements during a hold and a goal-directed movement task. The method reliably reconstructed the original angular kinematics of the artificial and human data with an average positional error of less than 0.05 rad for movement amplitudes of up to 0.9 rad, and did not yield hypermetric trajectories like previous procedures not accounting for damping.

Acceleration↗