[Barriers and facilitators of colorectal cancer screening access]. / Barreras y facilitadores del acceso al tamizaje de cáncer colorrectal.

INTRODUCTION: Colorectal cancer (CRC) is a global health problem. In the public sector of Bahía Blanca, CRC screening is opportunistic, through the request of fecal occult blood test (FOBT). The objective of this study is to describe access to CRC screening for the population with exclusive public coverage residing in the programmatic area 2 of the city between 2019 and 2021, and to identify the barriers and facilitators that determine it. METHODS: The annual and cumulative usage rate was estimated based on the number of patients who requested FOBT. The barriers and facilitators were studied through 41 semi-structured individual interviews to healthcare staff from the area, the Municipal Hospital, Health Secretariat and users/non-users of the system. RESULTS: The cumulative usage rate of FOBT during the period was less than 5%. Among the perceived barriers to screening, we found: the difficulties in accessing more complex studies for patients with positive FOBT, the lack of population awareness and perception of CRC as a health problem, the low adherence of professionals to guidelines. The territoriality and link of health centers with the population, as well as the willingness of users and professionals to incorporate screening, emerge as facilitators. CONCLUSION: The identification of barriers and facilitators will allow the design of context-adapted strategies that will strengthen screening in the future.

Introducción: El cáncer colorrectal (CCR) es un problema de salud a nivel global. En el sector público de Bahía Blanca, el tamizaje de CCR es oportunista, por solicitud de sangre oculta en materia fecal (SOMF). El objetivo de este trabajo es describir el acceso al tamizaje de CCR de la población con cobertura pública exclusiva que reside en el área programática 2 de la ciudad entre 2019 y 2021, y relevar las barreras y facilitadores que lo determinan. Métodos: Se estimó la tasa de uso anual y acumulada de SOMF. Las barreras y facilitadores se relevaron a través de 41 entrevistas individuales semi-estructuradas al personal de salud del área programática, el Hospital Municipal, Secretaría de Salud y usuarios/no usuarios del sistema. Resultados: La tasa acumulada de uso de SOMF en el período fue 4.8%. Entre las barreras al tamizaje percibidas se destacan: la dificultad en el acceso a estudios de mayor complejidad para pacientes con SOMF+, el desconocimiento y falta de percepción del CCR como un problema de salud por parte de la población y la baja adherencia de los profesionales a los lineamientos. La territorialidad y el vínculo de los centros de salud con la población, y la predisposición de usuarios y profesionales a incorporar el tamizaje surgen como facilitadores del mismo. Conclusiones: El relevamiento de las barreras orientará el diseño de estrategias adaptadas al contexto que permitan en el futuro reforzar el tamizaje.

[Effectiveness of strategies to increase adherence to colorectal cancer screening: a systematic review]. / Efectividad de estrategias para incrementar la adherencia al tamizaje de cáncer colorrectal: una revisión sistemática.

INTRODUCTION: Coverage for colorectal cancer screening in Argentina is very low. The objective of this review is to assess and synthesize the evidence on the effectiveness of strategies aimed at increasing adherence to colorectal cancer screening among healthcare personnel and the general population at average risk. METHODS: A review of systematic reviews (SRs) that evaluated the effectiveness of these strategies was conducted. Searches were performed in electronic databases, meta-search engines, the Cochrane Library, and through manual searching. Eligibility and inclusion criteria were applied, with assessment of the quality of the SRs using AMSTAR II and the certainty of evidence using the GRADE approach. Thematic synthesis was conducted based on the taxonomy of strategies proposed by Dougherty (patient/community-targeted, professionaltargeted, and other types of strategies). RESULTS: A total of 635 studies were identified, with 36 deemed eligible and 11 excluded due to insufficient quality, resulting in the inclusion of 10 SRs. A multiplicity of strategies with varying effectiveness were identified, with the majority targeting the population. Among these, education, self-testing with specimen collection at specific locations, and reminders stood out. For professionals, only education and reminders showed effectiveness. Combined strategies demonstrated greater effectiveness than isolated strategies. CONCLUSIONS: There is more evidence on strategies targeting the population than professionals. Combined strategies showed greater effectiveness, highlighting the need to explore barriers in both the population and professionals in each specific context in order to prioritize and combine those that have proven effective and would have a greater impact.

Introducción: En Argentina la cobertura al tamizaje de cáncer colorrectal (CCR) es muy baja. El objetivo de esta revisión fue relevar y sintetizar la evidencia sobre la efectividad de estrategias dirigidas a incrementar la adherencia al tamizaje de CCR del personal de salud y población con riesgo promedio. Métodos: Revisión de revisiones sistemáticas (RS) que evaluaron la efectividad de dichas estrategias. Búsqueda en bases de datos electrónicas, meta-buscadores, biblioteca Cochrane y búsqueda manual. Aplicación de criterios de elegibilidad e inclusión; con evaluación de la calidad de las RS a través del AMSTAR-II y la certeza de la evidencia por el método GRADE. Síntesis temática sobre la base de la taxonomía de estrategias propuesta por Dougherty (dirigidas al paciente/comunidad; a profesionales; otro tipo de estrategias). Resultados: Se identificaron 635 estudios; 36 fueron elegibles y 11 se descartaron por no contar con calidad suficiente, incluyéndose 10 RS. Se identificó una multiplicidad de estrategias de efectividad variada, la mayoría dirigida a la población. Entre estas, destacan la educación, el auto-test con recolección en lugares específicos y recordatorios. En el caso de profesionales, solo educación y recordatorios mostraron ser efectivas. La combinación de estrategias mostró tener mayor efectividad que las estrategias aisladas. Conclusiones: Es mayor la evidencia sobre estrategias dirigidas a la población que a profesionales. Las estrategias combinadas demostraron tener mayor efectividad, lo que destaca la necesidad de explorar, en cada contexto, las barreras en la población y en los profesionales para priorizar y combinar aquellas que demostraron ser efectivas y tendrían mayor impacto.

Identification of a Dexamethasone Mediated Radioprotection Mechanism Reveals New Therapeutic Vulnerabilities in Glioblastoma.

(1) Background: Despite the indisputable effectiveness of dexamethasone (DEXA) to reduce inflammation in glioblastoma (GBM) patients, its influence on tumour progression and radiotherapy response remains controversial. (2) Methods: We analysed patient data and used expression and cell biological analyses to assess effects of DEXA on GBM cells. We tested the efficacy of tyrosine kinase inhibitors in vitro and in vivo. (3) Results: We confirm in our patient cohort that administration of DEXA correlates with worse overall survival and shorter time to relapse. In GBM cells and glioma stem-like cells (GSCs) DEXA down-regulates genes controlling G2/M and mitotic-spindle checkpoints, and it enables cells to override the spindle assembly checkpoint (SAC). Concurrently, DEXA up-regulates Platelet Derived Growth Factor Receptor (PDGFR) signalling, which stimulates expression of anti-apoptotic regulators BCL2L1 and MCL1, required for survival during extended mitosis. Importantly, the protective potential of DEXA is dependent on intact tyrosine kinase signalling and ponatinib, sunitinib and dasatinib, all effectively overcome the radio-protective and pro-proliferative activity of DEXA. Moreover, we discovered that DEXA-induced signalling creates a therapeutic vulnerability for sunitinib in GSCs and GBM cells in vitro and in vivo. (4) Conclusions: Our results reveal a novel DEXA-induced mechanism in GBM cells and provide a rationale for revisiting the use of tyrosine kinase inhibitors for the treatment of GBM.

In-SEM micro-machining reveals the origins of the size effect in the cutting energy.

High-precision metal cutting is increasingly relevant in advanced applications. Such precision normally requires a cutting feed in the micron or even sub-micron dimension scale, which raises questions about applicability of concepts developed in industrial scale machining. To address this challenge, we have developed a device to perform linear cutting with force measurement in the vacuum chamber of an electron microscope, which has been utilised to study the cutting process down to 200 nm of the feed and the tool tip radius. The machining experiments carried out in-operando in SEM have shown that the main classical deformation zones of metal cutting: primary, secondary and tertiary shear zones-were preserved even at sub-micron feeds. In-operando observations and subsequent structural analysis in FIB/SEM revealed a number of microstructural peculiarities, such as: a substantial increase of the cutting force related to the development of the primary shear zone; dependence of the ternary shear zone thickness on the underlaying grain crystal orientation. Measurement of the cutting forces at deep submicron feeds and cutting tool apex radii has been exploited to discriminate different sources for the size effect on the cutting energy (dependence of the energy on the feed and tool radius). It was observed that typical industrial values of feed and tool radius imposes a size effect determined primarily by geometrical factors, while in a sub-micrometre feed range the contribution of the strain hardening in the primary share zone becomes relevant.

[Cross-cultural validation and telephonic reliability of modified "VIDA" questionnaire]. / Validación transcultural y confiabilidad telefónica del cuestionario "vida diaria del anciano" modificado.

Instrumental activities scales allow the assessment of the functional status of the elderly; however, those currently used have gender bias and insufficient cross-cultural validation. The main objectives of this study were to perform the cross-cultural validation of the modified "VIDA: Daily living of the elderly questionnaire", created in Spain, into the Spanish spoken language in the City of Buenos Aires, and to evaluate its telephonic reliability. The secondary objective was to assess the concurrent validity of the modified VIDA questionnaire with the Lawton and Brody scale. The experts discussion group assessed the questionnaire vocabulary and proposed modifications according to the local language. We performed a pilot study to evaluate its comprehension, vocabulary and length. Afterwards we interviewed patients in person and after 14 days by telephone. We analyzed the global, inter and intra-observer reliability in both, the in person and the telephonic questionnaire, obtaining intra-class correlation coefficients of 0.95 (CI 95% 0.91-0.99), 0.99 (CI 95% 0.97-1.00) and 0.94 (IC 95% 0.87-1.00) respectively. Additionally, we obtained a very good correlation in both modalities between the modified VIDA questionnaire and the Lawton and Brody scale, with no differences regarding the patient's gender. In conclusion, the modified VIDA questionnaire was cross-culturally adapted in Buenos Aires City. Its implementation is reliable and valid both in person and by telephone.

Validación transcultural y confiabilidad telefónica del cuestionario "vida diaria del anciano" modificado / Cross-cultural validation and telephonic reliability of modified "VIDA" questionnaire

Las escalas que evalúan las actividades instrumentales de la vida diaria permiten la valoración del estado funcional de los ancianos; sin embargo, las utilizadas habitualmente presentan sesgo de género e insuficiente validación transcultural. El objetivo principal de este estudio fue efectuar la validación transcultural del “Cuestionario VIDA: Vida Diaria del anciano” modificado, creado en España, al castellano de habla usual en la Ciudad de Buenos Aires y la evaluación de su confiabilidad en forma telefónica. Como objetivo secundario, evaluamos su validez concurrente con respecto a la escala de Lawton y Brody, tanto en forma presencial como telefónica. El grupo de discusión de expertos evaluó el vocabulario original del cuestionario y propuso modificaciones de acuerdo a la cultura local. Realizamos una prueba piloto para valorar el vocabulario, su comprensión y su longitud. Posteriormente encuestamos pacientes de manera presencial y a los 14 días de manera telefónica. Analizamos la confiabilidad global, inter e intraobservador, del cuestionario presencial y re-test telefónico, obteniéndose coeficientes de correlación intraclase de 0.95 (IC 95% 0.91 - 0.99), 0.99 (IC 95% 0.97-1.00) y 0.94 (IC 95% 0.87-1.00) respectivamente. Adicionalmente, obtuvimos muy buena correlación en ambas modalidades entre el cuestionario VIDA modificado y la escala de Lawton y Brody, sin diferencias en cuanto al género de los pacientes. En conclusión, el cuestionario VIDA modificado fue adaptado transculturalmente en la Ciudad de Buenos Aires. Su implementación es confiable y válida tanto de manera presencial como telefónica.

Instrumental activities scales allow the assessment of the functional status of the elderly; however, those currently used have gender bias and insufficient cross-cultural validation. The main objectives of this study were to perform the cross-cultural validation of the modified “VIDA: Daily living of the elderly questionnaire”, created in Spain, into the Spanish spoken language in the City of Buenos Aires, and to evaluate its telephonic reliability. The secondary objective was to assess the concurrent validity of the modified VIDA questionnaire with the Lawton and Brody scale. The experts discussion group assessed the questionnaire vocabulary and proposed modifications according to the local language. We performed a pilot study to evaluate its comprehension, vocabulary and length. Afterwards we interviewed patients in person and after 14 days by telephone. We analyzed the global, inter and intra-observer reliability in both, the in person and the telephonic questionnaire, obtaining intra-class correlation coefficients of 0.95 (CI 95% 0.91-0.99), 0.99 (CI 95% 0.97-1.00) and 0.94 (IC 95% 0.87-1.00) respectively. Additionally, we obtained a very good correlation in both modalities between the modified VIDA questionnaire and the Lawton and Brody scale, with no differences regarding the patient´s gender. In conclusion, the modified VIDA questionnaire was cross-culturally adapted in Buenos Aires City. Its implementation is reliable and valid both in person and by telephone.

Structure solution with ARCIMBOLDO using fragments derived from distant homology models.

Molecular replacement, one of the general methods used to solve the crystallographic phase problem, relies on the availability of suitable models for placement in the unit cell of the unknown structure in order to provide initial phases. ARCIMBOLDO, originally conceived for ab initio phasing, operates at the limit of this approach, using small, very accurate fragments such as polyalanine α-helices. A distant homolog may contain accurate building blocks, but it may not be evident which sub-structure is the most suitable purely from the degree of conservation. Trying out all alternative possibilities in a systematic way is computationally expensive, even if effective. In the present study, the solution of the previously unknown structure of MltE, an outer membrane-anchored endolytic peptidoglycan lytic transglycosylase from Escherichia coli, is described. The asymmetric unit contains a dimer of this 194 amino acid protein. The closest available homolog was the catalytic domain of Slt70 (PDB code 1QTE). Originally, this template was used omitting contiguous spans of aminoacids and setting as many ARCIMBOLDO runs as models, each aiming to locate two copies sequentially with PHASER. Fragment trimming against the correlation coefficient prior to expansion through density modification and autotracing in SHELXE was essential. Analysis of the figures of merit led to the strategy to optimize the search model against the experimental data now implemented within ARCIMBOLDO-SHREDDER (http://chango.ibmb.csic.es/SHREDDER). In this strategy, the initial template is systematically shredded, and fragments are scored against each unique solution of the rotation function. Results are combined into a score per residue and the template is trimmed accordingly.

Exploiting tertiary structure through local folds for crystallographic phasing.

We describe an algorithm for phasing protein crystal X-ray diffraction data that identifies, retrieves, refines and exploits general tertiary structural information from small fragments available in the Protein Data Bank. The algorithm successfully phased, through unspecific molecular replacement combined with density modification, all-helical, mixed alpha-beta, and all-beta protein structures. The method is available as a software implementation: Borges.

Practical structure solution with ARCIMBOLDO.

Since its release in September 2009, the structure-solution program ARCIMBOLDO, based on the combination of locating small model fragments such as polyalanine α-helices with density modification with the program SHELXE in a multisolution frame, has evolved to incorporate other sources of stereochemical or experimental information. Fragments that are more sophisticated than the ubiquitous main-chain α-helix can be proposed by modelling side chains onto the main chain or extracted from low-homology models, as locally their structure may be similar enough to the unknown one even if the conventional molecular-replacement approach has been unsuccessful. In such cases, the program may test a set of alternative models in parallel against a specified figure of merit and proceed with the selected one(s). Experimental information can be incorporated in three ways: searching within ARCIMBOLDO for an anomalous fragment against anomalous differences or MAD data or finding model fragments when an anomalous substructure has been determined with another program such as SHELXD or is subsequently located in the anomalous Fourier map calculated from the partial fragment phases. Both sources of information may be combined in the expansion process. In all these cases the key is to control the workflow to maximize the chances of success whilst avoiding the creation of an intractable number of parallel processes. A GUI has been implemented to aid the setup of suitable strategies within the various typical scenarios. In the present work, the practical application of ARCIMBOLDO within each of these scenarios is described through the distributed test cases.

Crystallographic ab initio protein structure solution below atomic resolution.

Ab initio macromolecular phasing has been so far limited to small proteins diffracting at atomic resolution (beyond 1.2 A) unless heavy atoms are present. We describe a general ab initio phasing method for 2 A data, based on combination of localizing model fragments such as small á-helices with Phaser and density modification with SHELXE. We implemented this approach in the program Arcimboldo to solve a 222-amino-acid structure at 1.95 A.

Plasma lactate concentration and muscle blood flow during dynamic exercise with negative-pressure breathing.

This study assessed the hypothesis that increasing cardiac filling pressure (CFP) would enhance contracting muscle blood flow (MBF) by stretching cardiopulmonary baroreceptors and attenuate the increase in plasma lactate concentration ([Lac(-)](p)) during dynamic exercise. Continuous negative-pressure breathing (CNPB) (-15 cmH(2)O) was used to increase the CFP by accelerating the venous return to the heart. In the first series of experiments, 10 men performed a graded exercise seated on a cycle ergometer with (N1) and without CNPB (C1). The increase in [Lac(-)](p) for N1 was attenuated at 60%, 90%, and 100% of maximal exercise intensity compared with that in C1 (P < 0.001). Also, the increases in mean arterial pressure (MAP) and plasma catecholamine concentrations were attenuated in N1 compared with those in C1 throughout the graded exercise (P < 0.05). However, heart rate and pulse pressure were not significantly influenced by CNPB. Second, we studied the impact of CNPB on forearm MBF during a rhythmic handgrip exercise in 5 of the 10 subjects. Forearm MBF was measured immediately after cessation of the exercise by venous occlusion plethysmography at rest, 30%, 50%, and 70% of maximal work load (WL(max)) with (N2) and without CNPB (C2). Forearm MBF and vascular conductance for both trials increased with the increase in intensity, but forearm skin blood flow measured by laser-Doppler flowmetry remained unchanged. MBF and vascular conductance in N2, however, increased more than in C2 at every intensity (P < 0.01) except for MBF at 70% WL(max), whereas the increase in MAP for N2 was attenuated compared with that in C2 (P < 0.05). Thus augmented active muscle vasodilation occurred in N2 with a lower increase in MAP compared with that in C2. These findings suggest that the stretch of intrathoracic baroreceptors, such as cardiopulmonary mechanoreceptors, by CNPB increased MBF by suppressing sympathetic nerve activity. The attenuation of the increase in [Lac(-)](p) might be caused, at least partially, by the increased MBF.

Changes in surface EMG parameters during static and dynamic fatiguing contractions.

The effect of contraction types on muscle fiber conduction velocity (MFCV), median frequency (MDF) and mean amplitude (AMP) of surface electromyography was examined in the vastus lateralis of 19 healthy male adults. The subjects performed knee extension both statically and dynamically until they were exhausted. The static contraction was a sustained isometric extension of the knee at a joint angle of 90 degrees with 50% of the maximum voluntary contraction (MVC) load. The dynamic contraction was a repetitive isotonic extension of the knee between the angles of 90 degrees and 180 degrees with the same 50% MVC load at a frequency of 10 times per minute. MFVC during the static contraction significantly decreased during the exercise (p < 0.01). On the other hand, MFVC during the dynamic contraction did not significantly change throughout the exercise. MDF decreased and AMP increased during both types of contractions (p < 0.01). Because the blood flow within the muscle is maintained during the dynamic contraction by enhanced venous return from the contracting muscle, these results suggested that MFVC is affected by the metabolic state in the muscle and the changes in MDF cannot be explained only by that of MFVC.

Control of the rate of phosphocreatine resynthesis after exercise in trained and untrained human quadriceps muscles.

We examined the effect of differences in exercise intensity on the time constant (tc) of phosphocreatine (PCr) resynthesis after exercise and the relationships between tc and maximal oxygen uptake (VO2max) in endurance-trained runners (n = 5) and untrained controls (n = 7) (average VO2max = 66.2 and 52.0 ml.min-1.kg-1, respectively). To measure the metabolism of the quadriceps muscle using phosphorus nuclear magnetic resonance spectroscopy, we developed a device which allowed knee extension exercise inside a magnet. All the subjects performed four types of exercise: light, moderate, severe and exhausting. The end-exercise PCr: [PCr+inorganic phosphate (P(i))] ratio decreased significantly with the increase in the exercise intensity (P < 0.01). Although there was little difference in the end-exercise pH, adenosine diphosphate concentration ([ADP]) and the lowest intracellular pH during recovery between light and moderate exercise, significant changes were found at the two higher intensities (P < 0.01). These changes for runners were smaller than those for the controls (P < 0.05). The tc remained constant after light and moderate exercise and then lengthened in proportion to the increase in intensity (P < 0.05). The runners had a lower tc at the same PCr and pH than the controls, particularly at the higher intensity (P < 0.05). There was a significant correlation between tc and [ADP] in light exercise and between tc and both end-exercise PCr and pH in severe and exhausting exercise (P < 0.05). The threshold of changes in pH and tc was a PCr: (PCr+P(i)) ratio of 0.5. There was a significant negative correlation between the VO2max and tc after all levels of exercise (P < 0.05). However, in the controls a significant correlation was found in only light and moderate exercise (P < 0.05). These findings suggest the validity of the use of tc at an end-exercise PCr: (PCr+P(i)) ratio of more than 0.5 as a stable index of muscle oxidative capacity and the correlation between local and general aerobic capacity. Moreover, endurance-trained runners are characterized by the faster PCr resynthesis at the same PCr and intracellular pH.

Muscle energetics in short-term training during hypoxia in elite combination skiers.

Four well-trained combination skiers were studied through pre- and post-training for the effects of short-term intermittent training during hypoxia on muscle energetics during submaximal exercise as measured by Phosphorus-31 nuclear magnetic resonance and maximal aerobic power (VO2max). The hypoxia and training in the cold was conducted in a hypobaric chamber and comprised 60-min aerobic exercise (at an intensity equivalent to the blood lactate threshold), using a cycle ergometer or a treadmill twice a day for 4, consecutive days at 5 degrees C, in conditions equivalent to an altitude of 2000 m (593 mm Hg). No change in VO2max was observed over the training period, while in the muscle energetics during submaximal exercise, the values of phosphocreatine/(phosphocreatine+inorganic phosphate) and intracellular pH were found to be significantly increased by training during hypoxia. During recovery, the time constant of phosphocreatine was found to have been significantly reduced [pre, 27.9 (SD 6.7) s; post, 22.5 (SD 4.7) s, P < 0.01]. The observed inhibition of phosphocreatine as well as that of intracellular pH changes after training during hypoxia and quicker recovery of phosphocreatine in submaximal exercise tests, may indicate improved oxidative capacity (i.e. a high adenosine 5'-triphosphate formation rate) despite the short-term hypoxia training.

Changes in magnetic resonance images in human skeletal muscle after eccentric exercise.

To investigate the time-course of changes in transverse relaxation time (T2) and cross-sectional area (CSA) of the quadriceps muscle after a single session of eccentric exercise, magnetic resonance imaging was performed on six healthy male volunteers before and at 0, 7, 15, 20, 30 and 60 min and 12, 24, 36, 48, 72 and 168 h after exercise. Although there was almost no muscle soreness immediately after exercise, it started to increase 1 day after, peaking 1-2 days after the exercise (P < 0.01). Immediately after exercise, T2 increased significantly in the rectus femoris, vastus lateralis and intermedius muscles (P < 0.05) and decreased quickly continuing until 60 min after exercise. At and after the 12th h, a significant increase was perceived again in the T2 values of the vastus lateralis and intermedius muscles (P < 0.01) [maximum 9.3 (SEM 2.8)% and 10.9 (SEM 2.2)%, respectively]. The maximal values were exhibited at 24-36 h after exercise. In contrast, the rectus femoris muscle showed no delayed-stage increase. Also, in CSA, an increase after 12 h was observed in addition to the one immediately after exercise in the vastus lateralis, intermedius and medialis and quadriceps muscles as a whole (P < 0.01), reaching the maximal values at 12-24 h after exercise. The plasma creatine kinase activity remained unchanged up to 24 h after and then increased significantly 48 h after exercise (P < 0.05). Beginning 12 h after exercise, the subjects whose T2 and CSA increased less than the others displayed a faster decrease in muscle soreness.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of endurance training on excessive CO2 expiration due to lactate production in exercise.

We attempted to determine the change in total excess volume of CO2 output (CO2 excess) due to bicarbonate buffering of lactic acid produced in exercise due to endurance training for approximately 2 months and to assess the relationship between the changes of CO2 excess and distance-running performance. Six male endurance runners, aged 19-22 years, were subjects. Maximal oxygen uptake (VO2max), oxygen uptake (VO2) at anaerobic threshold (AT), CO2 excess and blood lactate concentration were measured during incremental exercise on a cycle ergometer and 12-min exhausting running performance (12-min ERP) was also measured on the track before and after endurance training. The absolute magnitudes in the improvement due to training for CO2 excess per unit of body mass per unit of blood lactate accumulation (delta la-) in exercise (CO2 excess.mass-1.delta la-), 12-min ERP, VO2 at AT (AT-VO2) and VO2max on average were 0.8 ml.kg-1.l-1.mmol-1, 97.8 m, 4.4 ml.kg-1. min-1 and 7.3 ml.kg-1.min-1, respectively. The percentage change in CO2 excess.mass-1.delta la- (15.7%) was almost same as those of VO2max (13.7%) and AT-VO2 (13.2%). It was found to be a high correlation between the absolute amount of change in CO2 excess.mass-1.delta la-, and the absolute amount of change in AT-VO2 (r = 0.94, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)