SEARCH · PubMed Health

Results for “DOMS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 829 records · Page 46Linked to original sources

PubMed2001

Highly proliferative fibroblasts forming fibrotic focus govern metastasis of invasive ductal carcinoma of the breast.

We have already reported that invasive ductal carcinomas (IDCs) with fibrotic focus (FF) have more aggressive characteristics than those without FF. FF is composed of a mixture of fibroblasts and various amounts of collagen fibers, suggesting that highly proliferative fibroblasts forming FF increase the malignant potential of IDCs with FF. The purpose of this study was to examine whether there is a difference of proliferative activity of fibroblasts forming and not forming FF, which plays an important role in the tumor progression of IDCS: Two hundred three consecutive cases of IDC of the breast surgically treated at the National Cancer Center Hospital East formed the basis for this study. The proliferative activity of the fibroblasts forming the FF was immunohistochemically evaluated by using mouse MIB-1 monoclonal antibody against Ki-67 antigen. The MIB-1 labeling index (LI) is the percentage of fibroblasts forming FF that have positively stained nuclei, and 300 fibroblasts were counted in each FF. The significance of the proliferative activity of fibroblasts forming FF with regard to lymph node metastasis (LNM) or distant-organ metastasis (DOM) was compared with well-known prognostic parameters. Multivariate analysis demonstrated that high MIB-1 LI of fibroblasts forming FF significantly increased the relative risk of LNM and the hazard rate of DOM (P < .001 and P = .009). The present study indicated that the metastatic ability of IDCs with FF is highly dependent on the proliferative activity of the fibroblasts forming FF.

Adult↗

PubMed1998

SOX10 mutations in patients with Waardenburg-Hirschsprung disease.

Waardenburg syndrome (WS; deafness with pigmentary abnormalities) and Hirschsprung's disease (HSCR; aganglionic megacolon) are congenital disorders caused by defective function of the embryonic neural crest. WS and HSCR are associated in patients with Waardenburg-Shah syndrome (WS4), whose symptoms are reminiscent of the white coat-spotting and aganglionic megacolon displayed by the mouse mutants Dom (Dominant megacolon), piebald-lethal (sl) and lethal spotting (ls). The sl and ls phenotypes are caused by mutations in the genes encoding the Endothelin-B receptor (Ednrb) and Endothelin 3 (Edn3), respectively. The identification of Sox10 as the gene mutated in Dom mice (B.H. et al., manuscript submitted) prompted us to analyse the role of its human homologue SOX10 in neural crest defects. Here we show that patients from four families with WS4 have mutations in SOX10, whereas no mutation could be detected in patients with HSCR alone. These mutations are likely to result in haploinsufficiency of the SOX10 product. Our findings further define the locus heterogeneity of Waardenburg-Hirschsprung syndromes, and point to an essential role of SOX10 in the development of two neural crest-derived human cell lineages.

Amino Acid Sequence↗

PubMed2000

Fluorescent screening of phytoplankton and organic compounds in sea water.

The flow-through spectrofluorometers, FLUO-IMAGER, were developed to measure the abundance of phytoplankton, including the analysis of pigment composition and concentration of organic pollution and dissolved organic matter (DOM), in continuous mode. The measurements can be carried out without the time-consuming pretreatment of water samples. The analytical concept uses the technique of spectral fluorescent signatures (SFS), based on the systematized spectral library comprising the SFS of major phytoplankton species and chemical pollution. The SFS technique has been applied for several years in qualitative and quantitative screening of organic compounds and phytoplankton in the Baltic, North and Norwegian Seas. The results of the analysis of phytoplankton pigments, the dynamic processes of bloom development, DOM and oil pollution are presented.

Environmental Monitoring↗

PubMed2002

Complexities in ETS-domain transcription factor function and regulation: lessons from the TCF (ternary complex factor) subfamily. The Colworth Medal Lecture.

The ETS-domain transcription factor family can be divided into a series of subfamilies. Elk-1 represents the founding member of the ternary complex factor (TCF) subfamily. By focusing on the TCF subfamily, we can demonstrate the complexities that exist in the function and regulation of ETS-domain transcription factors. This article focuses on Elk-1 in detail and summarizes the functions of other TCFs. The key themes covered include the domain structure of the TCFs, the mechanisms of complex formation with serum response factor, regulation of TCFs by mitogen-activated protein kinase cascades, and transcriptional regulatory properties of the TCFs. Finally, the emerging role of the TCFs in vivo is discussed. A picture is developing indicating that, while these proteins exhibit significant sequence and functional conservation, key differences in their structure and regulation are being identified which may relate to unique functions of these proteins in vivo.

Amino Acid Sequence↗

PubMed2003

Functional study of rat 5-HT2A receptors using antisense oligonucleotides.

We studied the effects in rats of a 6-day intracerebroventricular (i.c.v) infusion of four different end-capped phosphorothioate-modified antisense oligonucleotides (AOs), specifically targeting different regions of the 5-hydroxytryptamine2A (5-HT2A) receptor mRNA, on central 5-HT2A receptor expression and 5-HT2A receptor-mediated behaviours. Only one of the AOs (sequence 4), directed against the 5'-untranslated region (from + 557 to + 577), specifically affected central 5-HT2A receptor expression and receptor-mediated behaviour. This AO (sequence 4) reduced binding of the 5-HT2A agonist 1-(2,5-dimethoxy-4-[125I]iodophenyl)-2-aminopropane ([125I]DOI) up to 25% in cortical areas, as measured by quantitative autoradiography. Cortical binding of the antagonist [3H]ketanserin was not affected. As the specific AO treatment presumably affects the synthesis of new receptor, we hypothesize that this newly synthesized receptor represents the major part of the functionally active, G protein coupled receptor. A 5-day infusion of AO (sequence 4) resulted in profound inhibition of the head-twitch response (HTR) to 1-(2,5-dimethoxy-4-methylphenyl)-2-aminopropane (DOM). In contrast, treatment with vehicle, sense oligonucleotides (SOs) and other AOs (sequences 1, 2 and 3) caused an increased DOM-induced HTR as well as a spontaneous HTR. The latter was abolished by treatment with the 5-HT2 receptor antagonist, ritanserin. Systematic investigation of the surgical and infusion procedures revealed that the enhanced HTR already appeared following drilling of the skull. This wounding can probably damage the blood-brain barrier and cause a stress-induced increase in serotonergic transmission. AO (sequence 4) treatment also abolished the spontaneous HTR. AO (sequence 4) treatment allowed the identification of specific central 5-HT2A receptor-mediated behaviours in the complex serotonergic syndrome induced by tryptamine in rats. Only bilateral convulsions and body tremors were significantly inhibited. The backward locomotion, hunched back and Straub tail were not affected, nor was cyanosis, an index of vasoconstriction induced by peripheral 5-HT2A receptor activation. Labelling of central 5-HT2C receptors by [3H]mesulergine, and 5-HT2C receptor-mediated anxiety were not attenuated by AO or SO treatment. Rats treated with AO (sequence 4) showed increased locomotor activity and a strong reactivity towards touching. We hypothesize that the down-regulation of functional 5-HT2A receptors may shift the balance between various 5-HT receptor subtypes. Our analysis of the behavioural consequences of AO treatment and the use of different AOs and SOs has shown that specific receptor-mediated behaviour can be identified.

Animals↗

PubMed2002

Interferential therapy: lack of effect upon experimentally induced delayed onset muscle soreness.

This study was designed to assess the analgesic effects of interferential therapy (IFT) on experimentally induced muscular pain under randomized, double-blind, placebo-controlled conditions. After ethical approval and written consent were obtained, 40 healthy human volunteers (20 males: 20 females) aged 18-25 years were recruited and randomly assigned to one of four experimental groups (n = 10 per group: male = female): IFT 1, IFT 2, control or placebo. Delayed onset muscle soreness (DOMS) was induced in the elbow flexors of the non-dominant arm of each subject using a single bout of eccentric exercises to exhaustion. Measurements of isometric peak torque, resting angle, mechanical pain threshold and visual analogue scales were performed at set time points. Treatment was applied for 30 min daily over the biceps brachii muscle, for five consecutive days, according to group allocation. IFT 1 received 10-20 Hz, whilst subjects in IFT 2 were treated with 80-100 Hz (bi-pole; carrier frequency: 4 kHz; pulse duration: 125 microseconds). For the placebo group, the procedure was identical to that in the active treatment groups; however, no interferential current was delivered. The control group received no treatment. No significant between group difference was identified at any time point (P > or = 0.14). However, some inconsistent, yet significant differences in daily treatment effects, interactive effects and effects over time were detected. Based on the results of this study it can be concluded that application of IFT at the parameters used here, had no overall beneficial effect on DOMS.

Adolescent↗

PubMed2000

Direct regulation of the Microphthalmia promoter by Sox10 links Waardenburg-Shah syndrome (WS4)-associated hypopigmentation and deafness to WS2.

The transcription factor Sox10 is genetically linked with Waardenburg syndrome 4 (WS4) in humans and the Dominant megacolon (Dom) mouse model for this disease. The pigmentary defects observed in the Dom mouse and WS4 are reminiscent of those associated with mutations in the microphthalmia (Mitf) gene, which encodes a transcription factor essential for the development of the melanocyte lineage. We demonstrate here that wild type Sox10 directly binds and activates transcription of the MITF promoter, whereas a mutant form of the Sox10 protein genetically linked with WS4 acts as a dominant-negative repressor of MITF expression and can reduce endogenous MITF protein levels. The ability of Sox10 to activate transcription of the MITF promoter implicates Sox10 in the regulation of melanocyte development and provides a molecular basis for the hypopigmentation and deafness associated with WS4.

Animals↗

PubMed1995

Cardiorespiratory, hormonal and haematological responses to submaximal cycling performed 2 days after eccentric or concentric exercise bouts.

Eccentric muscle actions are known to induce delayed-onset muscle soreness (DOMS) and muscle weakness (reduced static strength and dynamic peak power output) that may persist for several days. The aim of the present study was to determine whether DOMS-inducing exercise affects physiological responses to subsequent submaximal dynamic exercise. Physiological and metabolic responses to a standardized exercise task were measured 2 days after the performance of an eccentric or concentric exercise bout. Six healthy, untrained male subjects aged 30 +/- 7 years (mean +/- S.D.) performed repeated eccentric contractions during 30 min of bench stepping (47-cm step, 15 steps min-1). On another occasion, they performed concentric contractions by walking uphill (8% incline) for 30 min at 5 km h-1, which elicited a similar heart rate response to bench stepping. Two days after the eccentric or concentric exercise, the subjects cycled for 15 min on an electrically braked cycle ergometer at a work rate (172 +/- 37 W) equivalent to 80% VO2 max. The order of the preceding treatments was randomized and the treatments were carried out 2 weeks apart. Two days after the eccentric exercise, all subjects reported leg muscle soreness and exhibited elevated levels of serum creatine kinase activity (P < 0.01) and plasma cortisol concentration (P < 0.05). After uphill walking, the subjects were not sore and serum creatine kinase activity was unchanged. Minute volume, breathing frequency, respiratory exchange ratio, heart rate, rating of perceived exertion, venous blood lactate concentration and plasma cortisol concentration were all higher (P < 0.05) during cycling after eccentric exercise compared with after uphill walking. Increases in plasma catecholamine concentrations and numbers of circulating leucocytes after cycling at 80% VO2 max for 15 min were similar under both experimental conditions, but the delayed leucocytosis (at 150 min post-exercise) was significantly greater (P < 0.01) for the post-eccentric exercise condition. We conclude that dynamic submaximal exercise performed 2 days following exercise with a large eccentric component produces physiological responses that are indicative of a higher relative exercise stress. It is likely that such effects will significantly limit the level and duration of exercise that can be achieved in subsequent training bouts over several days.

Adult↗

PubMed1987

Metabolic fate and elimination in milk, urine and bile of deoxynivalenol following administration to lactating sheep.

Using a combination of radioisotopic counting and chromatographic detection techniques, the kinetics and metabolic fate of deoxynivalenol (DON) in plasma, urine and bile were studied in lactating sheep, as was the transmission of residues to milk. Following intravenous administration, the plasma clearance of 14C-DON-derived radioactivity was rapid and followed a tri-phasic decay curve comprised of a bi-exponential decrease in DON (rapid distribution phase, t1/2 alpha = 16.2 min; slower elimination phase t1/2 beta = 66.5 min) and the formation and elimination (t1/2 beta = 188.0 min) of its major plasma metabolite, DON-glucuronide conjugate, which accounted for 13% of the plasma radioactivity levels. DON was rapidly cleared from the body by metabolism to 7 possible metabolites, which were excreted essentially in the urine (91%) and to a lesser extent in the bile (6%). Most (67%) of the recovered radioactivity was in the form of the glucuronide conjugates of DON (54%) and the de-epoxide metabolite, DOM-1 (13%). Excretion of unmetabolized DON accounted for 11%. The remaining recovered dose (18%) comprised of minor amounts of DOM-1 (6%), DON-sulfate conjugate (2%) and 3 unidentified radioactive components (10%). Studies on the presence of DON-derived residues in milk indicated that, relative to the dose, only trace amounts were transmitted following either oral or iv administration of the toxin.

Animals↗

PubMed2006

Development of a rapid infiltration system for wastewater and river water treatment in Japan using granulated materials.

A rapid infiltration (RI) system using granulated materials was developed for wastewater and river water treatment. Granules were processed by optimized procedures from soil and waste materials with high sorption of recalcitrant dissolved organic matter (DOM) and phosphorus. Granule performance was examined by laboratory column and pilot-scale tests. During the first year of the pilot test, removal of phosphorus was removed from livestock-farm effluent at the hydraulic loading rate of 2 m/day was 50-70% and that of refractory DOM was 10-30%.

Adsorption↗

PubMed1990

Studies on the evaluation of feed protein for ruminants. 1. Passage of nitrogen fractions to the duodenum of dairy cows fed different protein and carbohydrate sources.

The duodenal passages of non-ammonia nitrogen (NAN), amino acid N (AA-N) and microbial N (MN) were measured in seven duodenal fistulated dairy cows (6130 kg FCM/305 d) during lactation receiving 30 different rations similar to those used in dairy practice. The rations consisted of roughage (protein-rich silages, hay) and concentrate mixture (corn, barley, oat) in a ratio of 60:40 on a DM basis or roughage/concentrate mixture/fodder beets in the proportions 60:20:20 or 60:0:40 respectively. N supplements consisted of soya bean meal and peas meal (untreated or treated with formaldehyde in each case), rapeseed meal, fish meal and urea. DM intake varied between 9.6 and 19.1 kg/d, the crude fibre content between 166 and 270 g/kg DM, the crude protein (CP) content between 111 and 184 g/kg DM, the AA content (N basis) of the CP between 51 and 82%, the unfermentable CP content of the CP between 23 and 49% and the organic matter digestibility between 70 and 79%. The duodenal passage of NAN was 24.2 +/- 2.7 g/kg DM intake, 34.9 +/- 4.1 g/kg apparently digestible organic matter (in total tract, DOM), 43.3 +/- 5.5 g/kg apparently digestible carbohydrates or 4.2 +/- 0.5 g/MJ net energy fat, (y +/- s, n = 90). The value measured for AA-N was 16.8 +/- 2.9 g/kg DM intake, and that for RNA-labelled microbial CP was 146 +/- 26 g/kg DOM. NAN passage (g/kg DM intake) correlated more closely with the duodenal digesta flow rate (DFR) (kg digesta/kg DM intake) as an intrinsic animal factor (r = 0.78) and with the rumen content dilution rate (RDR) (passage of microbial-free organic matter at duodenum/kg BW0.75.h) as a ration dependent factor (r = 0.64) than with the UDP fraction (% of ration CP) (r = 0.50) or other ration parameters. It was concluded that the specific effect of protein concentrates in mixed rations on duodenal NAN yields in lactating dairy cows is lower than hitherto assumed. The duodenal NAN yield of a single feedstuff or ration (g/kg DM) in cows is dependent on animal and feeding factors. The DFR could represents a suitable target for breeding activities.

Animal Feed↗

PubMed1999

Calculation of utilizable crude protein at the duodenum of cattle by two different approaches.

The duodenal flow of utilizable crude protein (crude protein minus endogenous protein) in cows was estimated using dietary parameters, first by multiple regression and secondly by the addition of microbial protein and undegraded feed protein. These estimates were compared with 327 results from experiments conducted with fistulated cows in Braunschweig-Völkenrode and Rostock-Dummerstorf. The regressions and the measurements for microbial protein synthesis as well as feed protein degradation and organic matter fermentation in the rumen were based on the same experimental data set. The prediction of utilizable crude protein (uCP) at the duodenum by regression with digested organic matter (kg DOM) and undegraded feed protein (g UDP) as predicting variables, was more accurate than the value given by microbial protein synthesis and rumen protein degradability. The regression model [g uCP = [188.5-(116.5 (UDP/CP))] DOM + 1.03 UDP] had the highest coefficient of determination (r2 = 0.91) and the lowest coefficient of variation (cv = 8.6); indicating the model's superiority over the other method of estimation.

Animals↗

PubMed2004

Evidence of underestimation in PAH sorption/desorption due to system nonequilibrium and interaction with soil constituents.

The hypothesis evaluated was that sorption/desorption experiments conducted under nonequilibrium conditions would sorb/desorb smaller amounts of polycyclic aromatic hydrocarbons (PAHs) in comparison to those conducted under an equilibrium condition. The magnitude of phenanthrene's (PHEs) sorption coefficient was approximately the same for both equilibrium and nonequilibrium conditions. However, when the initial PHE concentrations were varied, sorption nonequilibrium resulted in a 1.4-4.8% decrease in the actual PHE sorbed than those obtained under equilibrium conditions. Similarly, thermodynamic nonequilibrium led to a smaller pyrene (PYR) desorption. For example, when PYR was initially spiked at 10 mg/L, a total of 3.1 mg PYR/kg was desorbed under desorption nonequilibrium, whereas 3.6 mg/kg when equilibrium had been achieved. Mechanistic analysis of sorptive phenomena with respect to soil organic matter (SOM), clay minerals, and dissolved organic matter (DOM) demonstrated that both expandable clays and aliphatic SOM served as main sorbents for PAH sorption/desorption; that DOM was not a primary desorptive factor; and the interaction with clay minerals were stronger than that with SOM.

Adsorption↗

PubMed2002

A genomewide screen for autism-spectrum disorders: evidence for a major susceptibility locus on chromosome 3q25-27.

To identify genetic loci for autism-spectrum disorders, we have performed a two-stage genomewide scan in 38 Finnish families. The detailed clinical examination of all family members revealed infantile autism, but also Asperger syndrome (AS) and developmental dysphasia, in the same set of families. The most significant evidence for linkage was found on chromosome 3q25-27, with a maximum two-point LOD score of 4.31 (Z(max )(dom)) for D3S3037, using infantile autism and AS as an affection status. Six markers flanking over a 5-cM region on 3q gave Z(max dom) >3, and a maximum parametric multipoint LOD score (MLS) of 4.81 was obtained in the vicinity of D3S3715 and D3S3037. Association, linkage disequilibrium, and haplotype analyses provided some evidence for shared ancestor alleles on this chromosomal region among affected individuals, especially in the regional subisolate. Additional potential susceptibility loci with two-point LOD scores >2 were observed on chromosomes 1q21-22 and 7q. The region on 1q21-22 overlaps with the previously reported candidate region for infantile autism and schizophrenia, whereas the region on chromosome 7q provided evidence for linkage 58 cM distally from the previously described autism susceptibility locus (AUTS1).

Adolescent↗

PubMed1993

Impaired visual motion perception in the contralateral hemifield following unilateral posterior cerebral lesions in humans.

Contrast thresholds for a number of tasks were measured in the contralateral and ipsilateral upper quadrants of the visual field (eccentricity = 10 degrees) before and after an occipito-parietal surgical resection, in one patient, carried out for intractable epilepsy. Postoperatively the contrast thresholds for discriminating the speed of movement of drifting sine-wave gratings were elevated by greater than a log unit in the contralateral field with little or no change in the detection thresholds for the same stimuli. Contrast thresholds for opposite direction-of-motion (DOM) discrimination of a contrast modulated (CMod) grating (a 'non-Fourier' motion stimulus) were also elevated by about a log unit in the contralateral hemifield but thresholds for DOM discrimination of a sine-wave (luminance modulated, LMod) grating were unaffected. Contrast thresholds for orientation discrimination of stationary gratings (a non-motion task) were unaffected. This general pattern of results was found in two other patients following lateral occipital surgical resections. Eight other patients with occipito-temporal (two cases), parietal (three cases) and medial occipital lobe lesions (three cases) showed no difference between the two hemifields on any of the tasks. Comparison of the location of the lesions leads to the conclusion that damage to the lateral occipital gyri is responsible for the pattern of visual deficit observed. Damage to an extra-striate visual area concerned with motion perception (the human homologue of primate V5-MT) may have occurred. There has been no previous description of impairment of motion perception localized to a hemifield in humans. The characteristics of the residual motion perception in these cases is described further in the accompanying article [Plant and Nakayama (1993), Brain, 116, 1337-1353].

Adult↗

PubMed2006

Nutraceutical effects of branched-chain amino acids on skeletal muscle.

BCAA catabolism in skeletal muscle is regulated by the branched-chain alpha-keto acid dehydrogenase (BCKDH) complex, located at the second step in the BCAA catabolic pathway. The activity of the BCKDH complex is regulated by a phosphorylation/dephosphorylation cycle. Almost all of BCKDH complex in skeletal muscle under normal and resting conditions is in an inactive/phosphorylated state, which may contribute to muscle protein synthesis and muscle growth. Exercise activates the muscle BCKDH complex, resulting in enhanced BCAA catabolism. Therefore, exercise may increase the BCAA requirement. It has been reported that BCAA supplementation before exercise attenuates the breakdown of muscle proteins during exercise in humans and that leucine strongly promotes protein synthesis in skeletal muscle in humans and rats, suggesting that a BCAA supplement may attenuate muscle damage induced by exercise and promote recovery from the damage. We have examined the effects of BCAA supplementation on delayed-onset muscle soreness (DOMS) and muscle fatigue induced by squat exercise in humans. The results obtained showed that BCAA supplementation prior to squat exercise decreased DOMS and muscle fatigue occurring for a few days after exercise. These findings suggest that BCAAs may be useful for muscle recovery following exercise.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗

PubMed2000

Hyperbaric oxygen therapy does not affect recovery from delayed onset muscle soreness.

PURPOSE: This study investigated whether hyperbaric oxygen therapy (HBOT) improves recovery after exercise-induced muscle injury. METHODS: Healthy male subjects (N = 24) were randomly assigned to either a placebo group or a HBOT group. Subjects were tested for maximal isometric strength (preexercise) of their right elbow flexors. Each subject then completed a high-force eccentric workout of the elbow flexor muscle group to induce delayed onset muscle soreness (DOMS). On the seven successive days after this workout, the subjects were exposed to a hyperbaric environment of 2.5 ATA for 60 min, inspiring either a normoxic mixture (P(I)O2 = 0.2 ATA; placebo group) or a hyperoxic gas mixture (P(I)O2 = 2.5 ATA; HBOT group). Before the eccentric workout and daily for the next 10 d, measurements were obtained regarding: maximal isometric muscle strength of the elbow flexor muscles, right upper arm circumferences, and rating of the perceived muscle soreness. RESULTS: Isometric strength decreased significantly from preexercise levels of 25.1 +/- 3.8 kp to postexercise levels of 12.0 +/- 4.6 kp, for the HBOT group, and from 24.6 +/- 3.4 kp to 12.5 +/- 3.7 kp, respectively, for the placebo group. Over the 10-d recovery period, there was no difference in the rate of recovery of muscle strength between the two groups. Perceived soreness peaked at about 48 h after exercise with no difference between groups. Also, the exercise-induced increases in arm circumference were similar in the two groups. CONCLUSIONS: These results indicate that HBOT is not an effective therapy for the treatment of DOMS.

Adult↗

PubMed2001

The effects of eccentric velocity on activation of elbow flexors: evaluation by magnetic resonance imaging.

PURPOSE: To compare magnetic resonance imaging (MRI) signal intensity changes in the primary elbow flexors during two isotonic exercise protocols varying in eccentric velocity and the ratio of eccentric to concentric activity. METHODS: Twelve men performed two exercise protocols. The right and left arms were randomly assigned to one of two protocols that had the same workload (60% 1RM) and same total time of exercise (144 s) but differed in the velocity and ratio of eccentric to concentric activity (1:1 and 5:1 for the fast and slow protocols, respectively). MRI signal intensity changes were quantified pre- and post-exercises using an inversion recovery sequence with a 1.5T MRI system (TR = 2500 ms, TE = 90 ms, TI = 140 ms). Percent change in MRI signal intensity, rate of perceived exertion (RPE), and delayed onset muscle soreness (DOMS) were recorded and analyzed. RESULTS: The biceps brachii was found to be preferentially recruited during the fast protocol compared with the brachialis, whereas the brachialis was found to be preferentially recruited during the slow protocol (P < 0.05). The fast exercise protocol was perceived as being more strenuous (RPE = 8.3 +/- 2.1) than the slow (RPE = 5.4 +/- 1.5, P < 0.05) and produced DOMS in 58% of the tested subjects. CONCLUSIONS: These results suggest that agonists respond to various loading conditions nonhomogeneously. These findings may have implications with respect to exercise prescriptions for specific muscles.

Adult↗