RESUMO
The purpose of this study was to determine the effect of respiratory muscle training (RMT) on intermittent exercise performance, respiratory muscle strength (PI (max)), respiratory muscle fatigue (RMF), and dyspnea in soccer athletes. Collegiate soccer athletes (20 male, 7 female) were randomly divided into either a RMT or control condition during off-season conditioning. The RMT group performed a 30RM protocol (10 times weekly) for 5 weeks using a commercially-available training device, while the controls received no RMT. Performance was evaluated utilizing Level 1 of the Yo-Yo Intermittent Recovery Test (IRT) and dyspnea was assessed during and immediately following the IRT. RMF was quantified within 2 minutes (RMF2) and 10 minutes (RMF10) after completing the IRT. Following training, the RMT group significantly increased IRT performance by 216.6 +/- 231.0 meters (p = .008) while the 49.2 +/- 75.1 meter increase observed in the controls was not significant. PI (max) in the RMT group increased from 138.1 +/- 19.6 to 165.3 +/- 23.5 cmH (2)O (p < .001), with no significant change observed in the controls. RMT did not significantly affect RMF or dyspnea. In conclusion, RMT improved intermittent exercise performance in these soccer athletes. The mechanisms by which RMT improves performance warrant further study.
Assuntos
Desempenho Atlético/fisiologia , Exercícios Respiratórios , Força Muscular/fisiologia , Músculos Respiratórios/fisiologia , Adolescente , Dispneia/prevenção & controle , Feminino , Humanos , Masculino , Fadiga Muscular/fisiologia , Resistência Física/fisiologia , Futebol , Adulto JovemRESUMO
The aim of this study was to assess the value of rigid endoscopy in patients presenting with globus symptoms. We conducted a retrospective analysis of 250 patients who underwent rigid endoscopy for globus symptoms over a 12-month period. In 217 patients (86.8 per cent) the examination of the larynx, pharynx and upper oesophagus was entirely normal. Abnormal findings included cricopharyngeal spasm in 12 patients (4.8 per cent), reflux in 11 (4.4 per cent), pharyngitis in two (0.8 per cent), web in two (0.8 per cent), and retention cyst in three (1.2 per cent). The 95 per cent confidence interval (CI) for the mean number of persons with malignancy based on the Poisson distribution is 0 and 3.7 (0 and 14.8 as rates per 1000). The relationship between the clinical diagnosis and endoscopic findings was examined using the chi-square test, with a p value of 0.0001. These results suggest that patients presenting with globus sensation are unlikely to harbour neoplastic lesions and therefore rigid endoscopy may well be an inappropriate investigation in this group. The risks, costs and discomfort associated with this intervention can often be avoided.
Assuntos
Transtornos de Deglutição/diagnóstico , Endoscopia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sulfato de Bário , Transtornos de Deglutição/cirurgia , Esofagoscopia/métodos , Feminino , Humanos , Laringoscopia/métodos , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios/métodos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The term electronic nose describes an electronic system that is able to mimic the human sense of smell. Electronic noses have been developed over the last 10 or more years to perform a variety of identification tasks in various industries. More recently electronic noses have attracted new interest in their application in the field of medical diagnosis. The aim of this study is to explore the use of an electronic nose to identify and classify pathogens associated with ear, nose and throat (ENT) infections. In this study 90 bacterial swab samples were collected from 90 patients with ENT infections. Some of these samples were analysed immediately with a commercial electronic nose (Cyranose C320). Similar numbers of swabs were also taken from the same site of infection and were sent for microbiology culture and sensitivity. The electronic nose diagnosis was compared with the microbiology diagnosis and it was found that the electronic nose diagnosis was correct in 88.2 per cent of the cases, which is an encouraging result.
Assuntos
Infecções Bacterianas/diagnóstico , Eletrônica Médica/instrumentação , Odorantes/análise , Otorrinolaringopatias/diagnóstico , Infecções Bacterianas/microbiologia , Técnicas de Tipagem Bacteriana/métodos , Humanos , Otite Externa/microbiologia , Otite Média Supurativa/microbiologia , Otorrinolaringopatias/microbiologia , Sensibilidade e Especificidade , Manejo de Espécimes/métodosRESUMO
The purpose of this study was to quantify interrelationships among thigh muscle co-contraction, quadriceps muscle strength, and the aerobic demand of walking in 13 children with spastic hemiplegic cerebral palsy (CP). During Session 1, subjects were familiarized with testing procedures, given five minutes of treadmill walking practice, and completed quadriceps muscle strength testing. In Session 2, subjects performed three 5-min walking bouts on the treadmill at 0.67 m x s(-1) to further accommodate to treadmill ambulation. During Session 3, resting VO2 was measured and subjects walked at 0.67, 0.89, and 1.12 m x s(-1) for five minutes while oxygen uptake (VO2) and thigh muscle co-contraction data were collected. Results demonstrated that no significant relationship existed between net VO2 and measures of thigh muscle co-contraction or quadriceps muscle strength. In addition, thigh muscle co-contraction was not shown to be associated with quadriceps muscle strength. Collectively, thigh muscle co-contraction and quadriceps muscle strength explained 13. 5%, 6.2%, and 2.2% of the variance in VO2 at 0.67, 0.89, and 1.12 m x s(-1), respectively. Viewed in concert, these results suggest that the walking energy expenditure of children with spastic hemiplegic CP is not influenced by the level of thigh muscle co-contraction or quadriceps muscle strength.
Assuntos
Paralisia Cerebral/fisiopatologia , Metabolismo Energético/fisiologia , Contração Muscular/fisiologia , Músculo Esquelético/fisiopatologia , Caminhada/fisiologia , Criança , Feminino , Hemiplegia/fisiopatologia , Humanos , Masculino , Debilidade Muscular/fisiopatologia , Coxa da Perna/fisiopatologiaRESUMO
Matrix metalloproteinases (MMPs) and cyclooxygenase-2 (COX-2) are expressed in both sporadic and familial adenomatous colonic polyps and tumours and have been independently shown to play causal roles in intestinal tumour formation in mouse models of colon cancer. The apparent roles of these enzymes in intestinal tumorigenesis led us to examine, in the Min mouse model of colon cancer, if selective COX-2 and MMP inhibitors provide additive or synergistic therapeutic benefits in intestinal tumour prevention. The broad-spectrum MMP inhibitor (A-177430; MMPI) and the selective COX-2 inhibitor (A-285969; COX-2I) both showed dose-dependent inhibition of the number of adenomas in Min mice. Using suboptimal doses, the MMPI reduced tumour multiplicity by 32%, the COX-2I by 48% and, both agents in combination resulted in a 67% decrease compared to control demonstrating a cooperative effect on intestinal tumorigenesis. Apoptosis, proliferation, and angiogenesis were assayed in tumors from each treatment group. These agents in combination allowed for a lowered dosage to be administered to achieve significant biological effects. Clinically, this could potentially reduce side effects associated with currently used MMP and COX-2 inhibitors. Together, these compounds could represent an easily tolerated chemopreventive approach.
Assuntos
Adenoma/tratamento farmacológico , Inibidores de Ciclo-Oxigenase/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Neoplasias Intestinais/tratamento farmacológico , Isoenzimas/metabolismo , Inibidores de Metaloproteinases de Matriz , Peptídeos Cíclicos/uso terapêutico , Prostaglandina-Endoperóxido Sintases/metabolismo , Adenoma/patologia , Animais , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Neoplasias Intestinais/patologia , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Snoring is a significant problem with both social and medical manifestations. This article addresses the current management of the simple snorer from initial out-patient assessment to definitive treatment.
Assuntos
Apneia Obstrutiva do Sono/complicações , Ronco/etiologia , Endoscopia/métodos , Humanos , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Oximetria/métodos , Polissonografia/métodos , Respiração , Sono/fisiologia , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/terapia , Ronco/fisiopatologia , Ronco/terapiaRESUMO
The aim of this study was to retrospectively survey patients who had undergone radiofrequency ablation of the soft palate for snoring complaints. Fifty-nine patients who had undergone radiofrequency ablation were sent an anonymous questionnaire to assess snoring (using visual analogue scales), pain and satisfaction with the procedure. Sixty-one per cent of the group returned the questionnaire. The mean time since operation was 17.5 months. Taking an improvement in snoring of 50 per cent or greater as a successful operation, snoring improvement occurred in 22 per cent. Post-operative pain was minimal with a median pain score of zero. Information was requested on whether the patient would undergo this procedure again, 50 per cent responded that they would and 44 per cent would advise a friend in the same situation to have this procedure. Radiofrequency ablation of the soft palate, as in other forms of surgery for snoring, seems to have a relapse rate over the long-term.
Assuntos
Ablação por Cateter/métodos , Palato Mole/cirurgia , Ronco/cirurgia , Humanos , Medição da Dor , Dor Pós-Operatória/etiologia , Satisfação do Paciente , Estudos Retrospectivos , Resultado do TratamentoRESUMO
It is common to see cholesterol granuloma in the mastoid air cells, less common in the orbit, and uncommon in the paranasal sinuses. Cholesterol granuloma is thought to be due to an interruption to normal aeration with impaired lymphatic drainage, resulting in a closed cavity where it may form. These expanding cysts cause bone destruction and compression of the surrounding structures that lead to clinical symptoms. Diagnosis and management of cholesterol granuloma cysts can be challenging. Magnetic resonance imaging (MRI) and computed tomographic (CT) scans are usually diagnostic. We present a rare case of cholesterol granuloma in the frontal sinus, few cases have been reported in the literature.
Assuntos
Colesterol , Seio Frontal/patologia , Granuloma de Corpo Estranho/patologia , Doenças dos Seios Paranasais/patologia , Idoso , Humanos , Masculino , Tomografia Computadorizada por Raios XRESUMO
Maffucci's syndrome is a rare congenital non-inherited condition, characterized by multiple enchondromata, cutaneous haemangiomata and more recently spindle-cell haemangioma-endotheliomata. It is associated with an increased risk of malignancy including intracranial chondrosarcomas. Early diagnosis is crucial; screening patients with Ollier's disease is recommended. The treatment of choice for these intracranial cartilaginous tumours is complete surgical excision but this is often difficult to achieve due to difficult access and relationships with neurovascular structures. An alternative treatment is proton-beam therapy. We report a case of Maffucci's syndrome; illustrating the typical clinical and radiological features as well as the known complications of the condition.
Assuntos
Encondromatose , Encondromatose/diagnóstico , Dedos/diagnóstico por imagem , Humanos , Úmero/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Radiografia , Escápula/diagnóstico por imagem , Crânio/patologiaRESUMO
Cystic fibrosis (CF) patients receive repeated courses of aminoglycoside therapy. These patients would consequently be expected to be more susceptible to cochleotoxicity, a recognized side effect with single courses of aminoglycoside therapy. The primary aim of this retrospective study was to establish the incidence and severity of auditory deficit in CF patients. Standard (0.25- to 8-kHz) and high-frequency (10- to 16-kHz) pure-tone audiometry was carried out in 70 CF patients, and the results were compared with the results from 91 control subjects. These subjects were further divided into pediatric and adult groups. Of 70 CF patients, 12 (1 pediatric) displayed hearing loss considered to be caused by repeated exposure to aminoglycosides. There was a nonlinear relationship between the courses of therapy received and the incidence of hearing loss. The severity of the loss did not appear to be related to the number of courses received. Assuming the risk of loss to be independent for each course, preliminary estimates of per course risk of hearing loss were less than 2%. Upon comparison with previous clinical studies and experimental work, these findings suggest that the incidence of cochleotoxicity in CF patients is considerably lower than would be expected, suggesting that the CF condition may confer protection against aminoglycoside cochleotoxicity.
Assuntos
Antibacterianos/efeitos adversos , Fibrose Cística/tratamento farmacológico , Surdez/induzido quimicamente , Gentamicinas/efeitos adversos , Tobramicina/efeitos adversos , Adolescente , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Antibacterianos/uso terapêutico , Audiometria de Tons Puros , Criança , Fibrose Cística/sangue , Overdose de Drogas , Quimioterapia Combinada , Uso de Medicamentos/tendências , Gentamicinas/administração & dosagem , Gentamicinas/sangue , Gentamicinas/uso terapêutico , Audição/efeitos dos fármacos , Humanos , Ondas de Rádio , Tobramicina/administração & dosagem , Tobramicina/sangue , Tobramicina/uso terapêuticoRESUMO
A novel series of biaryl ether reverse hydroxamate MMP inhibitors has been developed. These compounds are potent MMP-2 inhibitors with limited activity against MMP-1. Select members of this series exhibit excellent pharmacokinetic properties with long elimination half-lives (7 h) and high oral bioavailability (100%).
Assuntos
Ácidos Hidroxâmicos/síntese química , Inibidores de Metaloproteinases de Matriz , Administração Oral , Animais , Antineoplásicos/sangue , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Disponibilidade Biológica , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Meia-Vida , Ácidos Hidroxâmicos/química , Concentração Inibidora 50 , Injeções Intravenosas , Macaca fascicularisRESUMO
Modification of the biphenyl portion of MMP inhibitor 2a gave analogue 2i which is greater than 1000-fold selective against MMP-2 versus MMP-1. The stereospecific synthesis of both enantiomers of 2i was achieved beginning with (S)- or (R)-benzyl glycidyl ether. The (S)-enantiomer, 11 (ABT-770), is orally bioavailable and efficacious in an in vivo model of tumor growth.
Assuntos
Compostos de Bifenilo/farmacocinética , Ácidos Hidroxâmicos/farmacocinética , Inibidores de Metaloproteinases de Matriz , Administração Oral , Animais , Antineoplásicos/sangue , Antineoplásicos/síntese química , Antineoplásicos/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Compostos de Bifenilo/sangue , Compostos de Bifenilo/síntese química , Divisão Celular/efeitos dos fármacos , Cães , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Meia-Vida , Haplorrinos , Ácidos Hidroxâmicos/sangue , Ácidos Hidroxâmicos/síntese química , Concentração Inibidora 50 , Injeções Intravenosas , Taxa de Depuração Metabólica , Neoplasias Experimentais/tratamento farmacológico , Ratos , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
A case of an intracochlea acoustic neuroma that was diagnosed radiologically is presented and discussed.
Assuntos
Imageamento por Ressonância Magnética , Neuroma Acústico/diagnóstico , Adulto , Audiometria de Tons Puros , Técnicas de Diagnóstico Otológico , Orelha Interna , Seguimentos , Perda Auditiva/diagnóstico , Perda Auditiva/etiologia , Humanos , Masculino , Monitorização Fisiológica , Neuroma Acústico/complicações , Zumbido/diagnóstico , Zumbido/etiologiaRESUMO
A retrospective case notes review using pain visual analogue scale (VAS) and assessment of analgesia required by patients in the post-operative period at 1, 3, 6, 12 and over 12 months following acoustic neuroma resection was performed. Glasgow Benefit Inventory (GBI) score was used to assess the change of quality of life and its relationship to pain following surgery. Questionnaires of 71 patients were included in the study, 23 of whom underwent wide craniotomy including dissection of upper cervical musculature (CE), 25 wide craniotomy with replacement of bone flap (CO) and 23 minimally invasive, approximately 2 x 2 cm, minicraniectomy (MCE). The minicraniectomy resulted in significantly diminished pain from third month post surgery as compared with wide craniectomy (p < 0.05) and patients required less analgesia. Similarly, CO patients have experienced significantly less pain than CE patients (p < 0.05), but only after 12 months following surgery. Although consistently less in absolute visual analogue scores, there was no statistically significant difference between the amount of pain recorded by CO and MCE patients. There was no correlation between gender or age and the VAS pain score. The mean Glasgow Benefit Inventory score for all patients was -6.6, and there was no significant difference between operation types, genders or age. Although bone flap replacement appears to diminish the amount of post-operative pain, minimal invasive technique resulted in least pain following acoustic neuroma resection in our patients.
Assuntos
Cefaleia/diagnóstico , Neuroma Acústico/cirurgia , Procedimentos Cirúrgicos Otológicos , Complicações Pós-Operatórias/diagnóstico , Feminino , Cefaleia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Occipital , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Inquéritos e QuestionáriosRESUMO
Few data exist concerning the reproducibility of stable oxygen uptake (VO(2)) values during level treadmill walking in young able-bodied children. To address this issue, 41 able-bodied 6-year-olds (19 boys, 22 girls, X height=117.2+/-4.7 cm, X body mass=21.8+/-2.5 kg) were tested on two occasions. In session 1, subjects were familiarized with the laboratory environment and performed 5 min of level treadmill walking at 1.34 m s(-1). During session 2, each child completed 30 min (three 10-min trials) of level treadmill walking at 1.34 m s(-1). For each 10-min trial, mean VO(2) was determined by averaging VO(2) values obtained from analysis of two 2-min expired gas samples. While the mean VO(2) for trial 1 was higher than values recorded for trials 2 and 3, effect sizes corresponding to these differences were low (=0.16). Average within subject coefficient of variation and intraclass reliability coefficient values for VO(2) across the three walking trials were 2. 0+/-1.5% and 0.96, respectively. Viewed collectively, these results suggests that among young able-bodied children, acceptably and reproducible stable VO(2) values during level treadmill walking can be obtained within 10 min if data collection is preceded by exposure to testing procedures and a brief period of treadmill walking practice.
Assuntos
Metabolismo Energético , Caminhada/fisiologia , Criança , Teste de Esforço , Feminino , Humanos , Masculino , Consumo de Oxigênio , Prática Psicológica , Reprodutibilidade dos Testes , Fatores de TempoRESUMO
The objective of this investigation was to determine the individual contributions of perceived daily, major, and total stressors to blood pressure in early adolescent children. Toward this goal, cardiovascular risk factors were assessed in 74 6th-grade students. Height and body weight, measured in standard fashion, were used to calculate body mass index (BMI). Waist and hip circumferences and triceps and calf skinfolds were taken to determine the distribution and percentage of body fat, respectively. Seated resting blood pressure was obtained using a mercury sphygmomanometer. The dietary sodium-to-potassium ratio was calculated from a food intake questionnaire. Family history of hypertension was self-reported by participant's parents, and physical activity and perceived stress levels were determined by questionnaire. When added to the hierarchical regression models, the perceived stress variables did not significantly predict any additional variance in systolic or diastolic blood pressure in this early adolescent sample. Additionally, bivariate correlations between the stress variables and blood pressure were nonsignificant. The nonpsychological hypertension risk factors accounted for 25%-35% of the total variance in systolic and diastolic blood pressure. Further, regression analyses revealed that with the exception of BMI and the sodium-to-potassium ratio, no other risk factors were independent predictors of systolic or diastolic blood pressure. Further identification and understanding of environmental precursors of childhood hypertension is recommended.
Assuntos
Hipertensão/psicologia , Estresse Psicológico/fisiopatologia , Adolescente , Determinação da Pressão Arterial , Índice de Massa Corporal , Criança , Comportamento Alimentar , Feminino , Predisposição Genética para Doença , Humanos , Hipertensão/diagnóstico , Hipertensão/etiologia , Hipertensão/prevenção & controle , Masculino , North Carolina , Potássio na Dieta/administração & dosagem , Escalas de Graduação Psiquiátrica , Análise de Regressão , Fatores de Risco , Estudos de Amostragem , Instituições Acadêmicas , Sódio na Dieta/administração & dosagem , Inquéritos e QuestionáriosRESUMO
Members of the matrix metalloprotease (MMP) family are implicated in the progression of several malignancies including prostate cancer due to their ability to break down extracellular matrix (ECM) components. In this study, we have evaluated the ability of a synthetic MMP inhibitor (A-177430) to block tumor growth and metastases in a syngeneic model of rat prostate cancer. In an in vitro substrate assay, A-177430 exhibited nanomolar potency (IC(50) 2-6 nM) against the enzymatic activity of several MMPs. For in vivo studies, male Copenhagen rats were injected s.c. with Mat Ly Lu rat prostate cancer cells (1 x 10(6) cells ) into the right flank and animals were administered i.p.with different doses (10-100 mg/kg per day) of A-177430 for 16 days. Administration of A-177430 resulted in a dose-dependent decrease in tumor volume as compared to a control group of animals receiving vehicle alone. The maximum dose (100 mg/kg per day) of A-177430 exhibited complete arrest in tumor growth and prevented the development of macroscopic tumor metastases to lungs without exhibiting any noticeable side effects. Histologic examination of primary tumors from experimental animals showed extensive tumor necrosis and decreased tumor angiogenesis as determined by factor VIII staining of primary tumors following A-177430 treatment. These primary tumors from experimental animals also exhibited a significant increase in tumor cell DNA fragmentation as determined by TUNEL assay. Collectively, these results demonstrate the ability of MMP inhibitors to block tumor growth and metastases by blocking ECM degradation and by inhibiting tumor angiogenesis and promotion of prostate cancer cell apoptosis in vivo.
Assuntos
Inibidores Enzimáticos/farmacologia , Inibidores de Metaloproteinases de Matriz , Metástase Neoplásica , Peptídeos Cíclicos/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Animais , Divisão Celular/efeitos dos fármacos , Colágeno/metabolismo , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Laminina/metabolismo , Masculino , Transplante de Neoplasias , Peptídeos Cíclicos/química , Proteoglicanas/metabolismo , Ratos , Ratos Endogâmicos , Fatores de Tempo , Distribuição Tecidual , Células Tumorais CultivadasRESUMO
Twenty-six adult cystic fibrosis patients were studied to compare nasal disease with their laboratory correlates including skin testing, immunoglobulin and Aspergillus fumigatus precipitin levels, saccharin testing and sputum cultures. Six patients were asymptomatic and all of these had negative skin tests, normal IgE levels and negative Aspergillus fumigatus precipitins. Thirteen patients had rhinitis, 12 had positive skin-testing for common allergens, 10 elevated IgE levels and nine positive Aspergillus fumigatus precipitins. Seven patients had polyps, all had normal IgE levels and negative Aspergillus fumigatus precipitins, six had positive skin testing for common allergens. There also appeared to be a relationship between Pseudomonas spp. colonization and positive skin testing.
Assuntos
Fibrose Cística/complicações , Doenças Nasais/complicações , Infecções Oportunistas/complicações , Adolescente , Adulto , Aspergilose/complicações , Aspergillus fumigatus/imunologia , Feminino , Humanos , Masculino , Pólipos Nasais/complicações , Doenças Nasais/microbiologia , Estudos Prospectivos , Infecções por Pseudomonas/complicações , Rinite/complicações , Testes CutâneosRESUMO
The case history is presented of a patient with acute respiratory failure complicated by nasal obstruction resulting in intolerance of nasal ventilation. Urgent insertion of nasal stents permitted restoration of ventilation with resolution of breathlessness and stabilisation of arterial blood gases.
Assuntos
Fibrose Cística/complicações , Ventilação com Pressão Positiva Intermitente/instrumentação , Insuficiência Respiratória/terapia , Stents , Adulto , Humanos , Masculino , Obstrução Nasal/terapia , Insuficiência Respiratória/etiologiaRESUMO
Few studies have been conducted documenting the length of time required for young children to achieve stable measures of running economy. Hence the purpose of this study was to quantify within- and between-day stability in running economy among young children. To address this issue, 30 6-year olds (16 girls, 14 boys) completed three test sessions within a 2 wk period. During Sessions 1 and 2 subjects performed three 5 min level treadmill runs at 2.23 m x sec(-1). During Session 2 expired air was collected during the last 2 min of each 5 min run (R1, R2, R3) and analyzed to determine VO2. In Session 3 subjects completed a single 5 min run (R4) at 2.23 m x sec(-1) and VO2 was measured during the last 2 min of running. Data analysis revealed no significant difference (p>0.05) in absolute or relative VO2 across trials. The average coefficient of variation for both absolute and relative VO2 among runs completed in Session 2 was 2.17 %, and the mean coefficient of variation for VO2 between R4 and the average VO2 of R1, R2, and R3 was 2.51 % and 2.35% for absolute and relative VO2, respectively. Moreover intraclass correlation coefficients for absolute and relative VO2 across all runs were 0.99 and 0.96, respectively. Viewed in concert, these results suggest that following 15 minutes of level treadmill running practice, stable within- and between-day measures of running economy can be obtained in young, prepubescent children.