The goal of this study was to assess the effects of repeated running bouts with end-expiratory breath holding (EEBH) up to the breaking point on muscle oxygenation. Eight male runners participated in three randomised sessions each including two exercises on a motorised treadmill. The first exercise consisted in performing 10–12 running bouts with EEBH of maximum duration either (separate sessions) at 60% (active recovery), 80% (passive recovery) or 100% (passive recovery) of the maximal aerobic velocity (MAV). Each repetition started at the onset of EEBH and ended at its release. In the second exercise of the session, subjects replicated the same procedure but with normal breathing (NB). Arterial oxygen saturation (SpO2), heart rate (HR) and the change in vastus lateralis muscle deoxy-haemoglobin/myoglobin (Δ[HHb/Mb]) and total haemoglobin/myoglobin (Δ[THb/Mb]) were continuously monitored throughout exercises. On average, the EEBHs were maintained for 10.1 ± 1.1 s, 13.2 ± 1.8 s and 12.2 ± 1.7 s during exercise at 60%, 80% and 100% of MAV, respectively. In the three exercise intensities, SpO2 (mean nadir values: 76.3 ± 2.5 vs 94.5 ± 2.5%) and HR were lower with EEBH than with NB at the end of the repetitions; whereas, the mean Δ[HHb/Mb] (12.6 ± 5.2 vs 7.7 ± 4.4 µm) and Δ[THb/Mb] (− 0.6 ± 2.3 vs 3.8 ± 2.6 µm) were, respectively, higher and lower with EEBH (p < 0.05). This study showed that performing repeated bouts of running exercises with EEBH up to the breaking point induced a large and early drop in muscle oxygenation compared with the same exercise with NB. This phenomenon was probably the consequence of the strong arterial oxygen desaturation induced by the maximal EEBHs.

La tomodensitométrie haute-résolution (TDM-HR) est essentielle au diagnostic positif de fibrose pulmonaire idiopathique (FPI). Nous avons étudié l’apport de différentes mesures morphologiques dans l’estimation du pronostic (Fig. 1). Dans ce travail prospectif monocentrique mené à l’hôpital Avicenne entre 2005 et 2010, 55 patients avec FPI incidente ont effectué une TDM-HR avec quantification de la fibrose et de l’emphysème, et mesure du diamètre de l’artère pulmonaire rapporté à la surface corporelle (AP/SC). Des explorations fonctionnelles respiratoires et une échocardiographie ont été réalisées. Le Composite Physiologic Index (CPI) a été calculé. Les paramètres fonctionnels respiratoires et morphologiques ont été corrélés entre eux, et leur impact pronostique sur la survie sans transplantation a été évalué. L’âge moyen était de 65 ± 11,7 ans. La capacité pulmonaire totale (CPT) était à 73,6 ± 13,36 % de la théorique, et la diffusion du CO (DLCO) à 43,8 ± 15,88 %. L’extension de la fibrose était bien corrélée à la diminution de la CPT (r = −0,38) et de la DLCO (r = −0,56), ainsi qu’au CPI (r = 0,58). Le rapport AP/SC était également corrélé à la DLCO (r = −0,41) et au CPI (r = 0,38), mais pas à la pression artérielle pulmonaire systolique (PAPs) estimée à l’échographie (r = 0,12), ni à l’extension de l’emphysème. Le rapport AP/SC, l’extension de la fibrose et de l’emphysème étaient tous trois prédictifs de survie sans transplantation dans un modèle de Cox univarié. Le meilleur modèle multivarié faisait ressortir le rapport AP/SC (HR = 1,19 [1,04–1,35] ; p = 0,014), l’extension de la fibrose (HR = 1,71 [1,25–2,37] ; p = 0,0007) et la PAPs (HR = 1,27 [1,05–1,53] ; p = 0,011), au détriment des paramètres fonctionnels. L’extension de la fibrose est un facteur pronostique important dans les FPI incidentes. Le rapport AP/SC possède une valeur pronostique indépendante, probablement car c’est un paramètre composite prenant en compte des mécanismes physiopathologiques multiples.

L'altération du transfert est constante et progressive au cours de la fibrose pulmonaire idiopathique (FPI), de mécanisme souvent complexe, pouvant impliquer un trouble de diffusion alvéolocapillaire et/ou une hypertension pulmonaire. La mesure combinée des capacités de diffusion du CO (DLCO) et du NO (DLNO) permet de décomposer les deux étapes du transfert en facteur membranaire (Dm) et volume capillaire (Vc) (Fig. 1). Dans cette étude prospective monocentrique menée à l'hôpital Avicenne entre 2005 et 2010, 55 patients avec FPI incidente ont effectué des explorations fonctionnelles respiratoires avec double diffusion, une tomodensitométrie haute-résolution et une échocardiographie. Le Composite Physiologic Index (CPI) a été calculé. Les paramètres fonctionnels respiratoires et morphologiques ont été corrélés entre eux, et leur impact pronostique sur la survie sans transplantation a été évalué. L'âge moyen à l'inclusion était de 65 ± 11,7 ans. Les valeurs fonctionnelles, en pourcentage de la théorique, étaient : CVF 77,2 ± 17,69 % ; DLCO 43,8 ± 15,88 % ; DLNO 39,0 ± 16,20 % ; Dm 53,3 ± 21,88 % ; Vc 42,1 ± 17,60 %. Le Dm était bien corrélé à la capacité vitale (r = 0,45), à la désaturation à la marche (r = −0,52), au score de fibrose tomodensitométrique (r = −0,60) et au CPI (r = −0,83). Le Vc possédait le même profil, mais ne corrélait pas avec la pression artérielle pulmonaire systolique estimée à l'échocardiographie (r = −0,08). La préservation du Dm était le paramètre fonctionnel le plus prédictif de survie sans transplantation dans un modèle de Cox univarié, et le seul restant significatif en multivarié (HR = 0,74 [0,56–0,97] ; p = 0,031). Les deux composantes du transfert sont diminuées chez nos patients avec FPI incidente. Ces résultats n'apportent pas d'explication physiopathologique supplémentaire concernant l'altération du transfert. En revanche, la mesure de Dm est le paramètre fonctionnel possédant la valeur pronostique la plus puissante, meilleure que la DLCO.

Les sténoses laryngo-trachéales dans les pemphigoïdes des muqueuses (PM) sont mal connues. Nous rapportons une série de 11 cas de PM avec sténose laryngo-trachéale. Cette étude rétrospective porte sur les patients suivis pour une PM dans notre centre du 01/01/2005 au 30/06/2012. Tous les patients ayant des symptômes ORL et/ou une atteinte OPH sévère ont eu au moins une endoscopie nasolaryngée. Si une sténose laryngée/trachéale était notée, les cas étaient inclus dans l'étude. Onze cas (3 % de l'ensemble des PM) dont 4 épidermolyses bulleuses acquises (EBA) ont été inclus. Tous avaient une PM sévère caractérisée par ≥ 3 sites atteints (n = 10) et/ou 1 fibrose conjonctivale sévère (≥ stade IIIA de Foster ; n = 3) et/ou 1 atteinte œsophagienne (n = 3). Le délai moyen entre les diagnostics (dg) de PM et de sténose était de 5,8 ans. Lors de la dernière visite avant le dg de sténose, 3 patients étaient en rémission quasi complète, 1 contrôlé, 5 non contrôlés et 2 en rechute. Lors du dg de sténose, étaient notés des symptômes laryngés (n = 5, dyspnée/dysphonie : 4/4) et/ou ORL autres (n = 9) ou aucun symptôme (n = 2). Les traitements en cours étaient dapsone (n = 8), immunosuppresseurs classiques (n = 2) et rituximab (RTX) (dernière perfusion < 1 an) (n = 5). L'examen endoscopique montrait une sténose supra-glottique (n = 9), sous-glottique (1 EBA) et trachéale (1 EBA). Le scanner confirmait le dg clinique dans 8/11 cas (73 %). La longueur moyenne de la sténose était de 19,4 mm, son calibre réduit de 22 à 50 %. Les EFR montraient une altération des débits aériens expiratoires et inspiratoires dans 5/8 cas (62 %). Les modifications thérapeutiques ont été l'introduction du cyclophosphamide (n = 2) ou du RTX (n = 2) ou l'intensification du RTX (n = 4). Un patient a eu une trachéotomie et un autre des dilatations trachéales. Avec un recul moyen de 5,4 ans, sur des critères clinico-radiologiques et fonctionnels, les lésions se sont améliorées, stabilisées et aggravées dans 6, 2 et 3/11 cas. Il s'agit de la plus grande série de sténoses trachéo-laryngées dans les PM. Celles-ci sont très rares et surviennent tardivement au cours de PM sévères, notamment dans les EBA (36,4 % de notre série). Elles sont le plus souvent asymptomatiques (55 %) et supra-glottiques (82 %), inconstamment objectivées par le scanner (73 %) et les EFR (62 %). La majorité des cas est améliorée ou stabilisée par les traitements systémiques (72 % des cas). Ces résultats indiquent l'importance d'un suivi au long cours des PM sévères avec des examens ORL réguliers associés à un scanner et des EFR pour le dépistage et la surveillance des sténoses laryngo-trachéales, même en l'absence de signe clinique trachéo-laryngé. Le traitement systémique pourrait permettre d'éviter la trachéotomie.

This study used an innovative technique of pulse oximetry to investigate whether swimmers can train under hypoxic conditions through voluntary hypoventilation (VH). Ten trained subjects performed a front crawl swimming series with normal breathing (NB), VH at high (VHhigh) and low pulmonary volume (VHlow). Arterial oxygen saturation was continuously measured via pulse oximetry (SpO2) with a waterproofed forehead sensor. Gas exchanges were recorded continuously and lactate concentration ([La]) was assessed at the end of each test. In VHlow, SpO2 fell down to 87% at the end of the series whereas it remained above 94% in VHhigh during most part of the series. Ventilation, oxygen uptake and end-tidal O2 pressure were lower in both VHhigh and VHlow than in NB. Compared to NB, [La] significantly increased in VHlow and decreased in VHhigh. This study demonstrated that swimmers can train under hypoxic conditions at sea level and can accentuate the glycolytic stimulus of their training if they perform VH at low but not high pulmonary volume.

Chronic beryllium disease: azathioprine as a possible alternative to corticosteroid treatmentTo the Editor: Chronic beryllium disease (CBD) is a chronic granulomatous disease that mainly affects the lungs.It occurs after beryllium exposure in genetically susceptible individuals with, most commonly, the HLA-DPb1 (Glu69) polymorphism [1].Beryllium particles are slowly washed out, causing delayed onsets of the disease and flare ups long after exposure to beryllium [2,3].

Background: Lactose malabsorption occurs frequently and the variable consequent intolerance may seriously impair quality of life. No reliable and convenient test method is in routine clinical practice. A recent animal study showed that the respiratory quotient changed significantly after ingestion of sucrose and lactose in naturally lactase-deficient rats.Aims: This exploratory study evaluated the relevance of monitoring the respiratory quotient after lactose ingestion to detect malabsorption.Methods: Healthy volunteers were identified and classified lactose absorbers and malabsorbers by a lactose tolerance test (25 g). After an overnight fast, a second lactose challenge was performed to monitor hydrogen excretion and respiratory quotient kinetics over 4 h. Participants also completed questionnaires to score and localise their gastrointestinal symptoms.Results: 20 subjects were enrolled (10 per group, 60% males, mean age 34 +/- 4 years). Respiratory quotient kinetics were different between absorbers and malabsorbers during the first 100 min after lactose ingestion (p < 0.01) and during the initial 30-50 min period. Respiratory quotient was significantly, positively correlated to peak glycaemia (R = 0.74) and negatively correlated to hydrogen excretion (R = -0.51) and symptoms score (R = -0.46).Conclusions: Indirect calorimetry could improve the reliability of lactose malabsorption diagnosis. Studies on larger populations are needed to confirm the validity of this test and propose a simplified measurement. (c) 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Darbepoetin (DAR), with or without granulocyte colony-stimulating factor (G-CSF), has proved effective in treating anemia in patients with lower-risk myelodysplastic syndrome (MDS), but its effects on quality of life (QoL) and exercise functioning are less well established. In this phase II study (no. NCT00443339), lower-risk MDS patients with anemia and endogenous erythropoietin (EPO) level <500 IU/L received DAR 500 μg once every 2 weeks for 12 weeks, with G-CSF added at week 12 in non-responders. Physical performance was assessed with the 6-min walking test and, for fit patients, maximal oxygen consumption (VO2max). QoL was evaluated using SF-36 and FACT-An tests. In 99 patients, erythroid response rate according to IWG 2006 criteria was 48 and 56 % at 12 and 24 weeks, respectively. Addition of G-CSF rescued 22 % of non-responders. In 48 % of the responders, interval between darbepoetin injections could be increased for maintenance treatment. Serum EPO level was the only independent predictive factor of response at 12 weeks, and its most discriminant cutoff value was 100 IU/L. QoL and VO2max showed improvement over time in responders, compared with non-responders. With a median follow-up of 52 months, median response duration was not reached, and 3-year cumulative incidence of acute myeloid leukemia and overall survival (OS) was 14.5 and 70 %, respectively. Baseline transfusion dependence, International Prognostic Score System (IPSS), and Revised IPSS accurately predicted OS from treatment onset. Tolerance of darbepoetin was good. In conclusion, this regimen of darbepoetin every 2 weeks yielded high response rates and prolonged response duration. Objective improvement in exercise testing and in patient-reported QoL confirms the clinical relevance of anemia correction with erythropoiesis-stimulating agents.

Imaging has a prominent role in the assessment of sarcoidosis diagnosis and outcome, which are extremely variable. Chest radiography staging helps predict the probability of spontaneous remission, and stage IV is associated with higher mortality. However, the reproducibility of reading is poor and changes in radiography and lung function are inconsistently correlated, which may be problematic for the monitoring of disease and treatment response. Chest computed tomography (CT) makes a great diagnostic contribution in difficult cases. Bilateral hilar lymphadenopathy with peri-lymphatic micronodular pattern is highly specific for sarcoidosis. CT is important for the investigation of pulmonary complications, including aspergilloma and pulmonary hypertension. CT improves the yield of bronchoscopy for obtaining a positive endobronchial or transbronchial biopsy. CT findings may also discriminate between active inflammation and irreversible fibrosis, with occasional influence on therapeutic decisions. Three CT patterns of fibrotic sarcoidosis are identified, with different functional profiles: predominant bronchial distortion is associated with obstruction; honeycombing is associated with restriction and lower diffusing capacity of the lung for carbon monoxide; whereas functional impairment is relatively minor with linear pattern. The clinical impact of correlations between CT severity scores and functional impairment is uncertain, except for its utility elucidating the mechanisms of airflow limitation, which include bronchial distortion, peribronchovascular thickening, air-trapping and bronchial compression by lymphadenopathy.

In July 2009, the patient’s condition worsened with PFT results comparable to those at first presentation (fig. 1). Treatment with azathioprine (150 mg?day) was then started as hydroxychloroquine was withdrawn. This treatment allowed a significant gradual clinical, radiological and functional improvement (fig. 2), with almost normalised PFTs by December 2011 (fig 1). SACE level also normalised. Only stable fibrotic chest CT lesions and DL,CO abnormalities persisted. Treatment efficacy and tolerance were still excellent after 17 months and a reduction of azathioprine (100 mg?day) was initiated.

This study aimed to determine the cardiovascular responses during a prolonged exercise with voluntary hypoventilation (VH). 7 men performed 3 series of 5-min exercise at 65% of normoxic maximal O (2) uptake under 3 conditions: (1) normal breathing (NB) in normoxia (NB (0.21)), (2) VH in normoxia (VH (0.21)), (3) NB in hypoxia (NB (0.157), inspired oxygen fraction=0.157). In both VH (0.21) and NB (0.157), there was a similar drop in arterial oxygen saturation and arterial O (2) content (CaO (2)) which were lower than in NB (0.21). Heart rate (HR), stroke volume, and cardiac output (-) were higher in VH (0.21) than in NB (0.21) during most parts of exercise whereas there was no difference between NB (0.157) and VH (0.21) or NB (0.21). HR variability analysis suggested an increased sympathetic modulation in VH (0.21) only. O (2) transport and oxygen uptake were generally not different between interventions. Mixed venous O (2) content (C-O (2)) was lower in NB (0.157) than in both VH (0.21) and NB (0.21) and not different between the latter. CaO (2)-C-O (2) was not different between NB (0.157) and NB (0.21) but lower in VH (0.21). This study shows that a prolonged exercise with VH leads to a greater cardiac activity, independent from the hypoxic effect. The greater - in VH compared to normal breathing seems to be the main factor for compensating the drop of arterial oxygen content.

Eight men performed three series of 5-min exercise on a cycle ergometer at 65% of normoxic maximal O(2) consumption in four conditions: (1) voluntary hypoventilation (VH) in normoxia (VH(0.21)), (2) VH in hyperoxia (inducing hypercapnia) (inspired oxygen fraction [F(I)O(2)] = 0.29; VH(0.29)), (3) normal breathing (NB) in hypoxia (F(I)O(2) = 0.157; NB(0.157)), (4) NB in normoxia (NB(0.21)). Using near-infrared spectroscopy, changes in concentration of oxy-(Delta[O(2)Hb]) and deoxyhemoglobin (Delta[HHb]) were measured in the vastus lateralis muscle. Delta[O(2)Hb - HHb] and Delta[O(2)Hb + HHb] were calculated and used as oxygenation index and change in regional blood volume, respectively. Earlobe blood samples were taken throughout the exercise. Both VH(0.21) and NB(0.157) induced a severe and similar hypoxemia (arterial oxygen saturation [SaO(2)] < 88%) whereas SaO(2) remained above 94% and was not different between VH(0.29) and NB(0.21). Arterialized O(2) and CO(2) pressures as well as P50 were higher and pH lower in VH(0.21) than in NB(0.157), and in VH(0.29) than in NB(0.21). Delta[O(2)Hb] and Delta[O(2)Hb - HHb] were lower and Delta[HHb] higher at the end of each series in both VH(0.21) and NB(0.157) than in NB(0.21) and VH(0.29). There was no difference in Delta[O(2)Hb + HHb] between testing conditions. [La] in VH(0.21) was greater than both in NB(0.21) and VH(0.29) but not different from NB(0.157). This study demonstrated that exercise with VH induced a lower tissue oxygenation and a higher [La] than exercise with NB. This was caused by a severe arterial O(2) desaturation induced by both hypoxic and hypercapnic effects.

Abstract Abstract 3812 Poster Board III-748 Background. DAR is a hyperglycosylated erythroblastic stimulating agent (ESA) with prolonged half life. Previous studies have shown high erythroid response rates with DAR +/− G-CSF in anemia of lower risk MDS (Mannone et al, Br J Haem 2006) with improvement in quality of life (QoL) (Greenberg et al, Blood 2009). In addition, treatment with ESAs in lower risk MDS does not increase progression to AML and may improve survival (Park, Grabar, Kelaidi et al, Blood 2008; Jadersten et al, JCO 2008). To better document the clinical relevance of erythroid response in those pts, we explored whether physical performance was also improved, using a new regimen of DAR+/− G-CSF. Patients and methods. In this phase II study (clinicaltrials.gov n° NCT00443339), low and int-1 MDS pts with anemia and endogenous EPO level <500 IU/L received DAR 500μg once every 2 weeks for 12 weeks. G-CSF could be added in the absence of response at week 12, and response reevaluated at week 24. Responders at week 12 or 24 could continue treatment. Some of the recruiting centers accepted to participate in an additional part of the study that included for patients (pts) at treatment onset, and at weeks 12 and 24 (i) Six minute Walk Test (6-min WT), a standardized test to evaluate global exercise capacity (distance walked in 6 minutes) (ii) In pts with no history of cardiac ischemia or heart failure and that could physicaly perform the test: peak oxygen consumption (VO2peak) evaluation on ergocycle, the reference method to assess physical performance (Albouaini et al, Heart 2007) (iii) QoL using SF-36 and FACT-AN tests. Results 99 pts were included by 17 centers. Median age was 72 (41-88), M/F 56/43, WHO distribution: RA 27%, RCMD 17%, RARS 41%, RAEB-1 15%. Karyotype was favorable in 80%, intermediate in 20%. IPSS was low in 60%, int-1 in 40%. Median Hb was 92 g/L and 30% of the pts were RBC transfusion dependent (median 2 RBC units/month). Median endogenous EPO level was 60 IU/L. At the date of analysis, 77 and 65 pts were evaluable at weeks 12 and 24, respectively. Erythroid response rate at 12 weeks (according to IWG 2006 criteria) was 53% and reached 65% (after addition of G-CSF) at 24 weeks. Multivariate analysis for predicting response revealed that endogenous EPO level <100 IU but not IPSS or transfusion dependence, was significantly associated with response (RR 78% vs. 52% for EPO<100 vs. >100 IU/L, resp, P=0.04). 48 of the pts evaluated for response belonged to the 6 centers that participated in the QoL and exercise capacity part of the trial. All had the 6-min WT and QoL, and VO2peak evaluation could be assessed in 20 of them. Mean VO2peak was 1067 mL/min before treatment and 1157 mL/min at week 24 (p=0.15). Mean 6-min WT was 382 m at onset and 418 m at week 24 (p=0.06). A significant improvement in VO2 and 6-min WT at week 24 (vs baseline) was observed in 60% (p=0.058) and 70% (p=0.052) of responders compared to 0% and 19% of non responders, resp. Significant improvement of exercise capacity was associated with achievement of Hb level >110g/L. QoL tests were also improved in responders at week 24 compared to non responders at week 24 (p=0.04). No severe adverse events of treatment were reported. Conclusion This regimen of DAR every 2 weeks yielded high response rates. An objective improvement in exercise testing with treatment was seen in 60 to 70% of responders, depending on the test used. This finding, and the QoL improvement also observed in responders, confirm the clinical relevance of anemia correction in that elderly population with lower-risk MDS. Disclosures: Off Label Use: Darbepoetin, off-label use in anemia related with lower-risk myelodysplastic syndromes.

Objective: To investigate airway involvement in patients with pulmonary sarcoidosis and airflow obstruction (AO) using high-resolution computed tomographyMethods: Forty-two sarcoidosis patients with AO and 42 matched sarcoidosis patients Without AO were retrospectively analyzed. High-resolution Computed tomographic patterns of airway involvement were bronchial distortion, peribronchovascular thickening, small airway obstruction, and bronchial compression by enlarged lymph nodes.Results: Interobserver agreement was good (kappa > 0.8). High-resolution computed tomographic patterns of airway involvement were found more frequently, scored higher, and were more often multiple (P < 0.05) in patients with AO than those without. Functional improvement tinder treatment was observed more frequently in patients with predominant peribronchovascular thickening compared with patients with predominant bronchial distortion (P < 0.03).Conclusions: In pulmonary sarcoidosis patients with AO, high-resolution computed tomography is a reliable tool to identify underlying airways involvements, which are often Multiple, and enables prediction of the therapeutic response.

Chronic beryllium disease (CBD) is a granulomatous disorder that affects the lung after exposure to beryllium. The present study reports short- and long-term evolution of granulomatous and fibrotic components in eight patients with severe CBD receiving corticosteroid therapy. Eight patients with confirmed CBD were studied at baseline, after initial corticosteroid treatment (4-12 months), at relapse and at the final visit. Beryllium exposure, Glu(69) (HLA-DPB1 genes coding for glutamate at position beta69) polymorphism, symptoms, pulmonary function tests (PFT), serum angiotensin-converting enzyme (SACE) and high-resolution computed tomography (HRCT) quantification of pulmonary lesions were analysed. The CBD patients were observed for a median (range) of 69 (20-180) months. After stopping beryllium exposure, corticosteroids improved symptoms and PFT (vital capacity +26%, diffusing capacity of the lung for carbon monoxide +15%), and decreased SACE level and active lesion HRCT score. In total, 18 clinical relapses occurred after the treatment was tapered and these were associated with SACE and active lesion HRCT score impairment. At the final visit, corticosteroids had completely stabilised all parameters including both HRCT scores of active lesions and fibrotic lesions in six out of eight patients. Corticosteroids were beneficial in chronic beryllium disease. They were effective in suppressing granulomatosis lesions in all cases and in stopping the evolution to pulmonary fibrosis in six out of eight patients.

This study investigated the effects of training with voluntary hypoventilation (VH) at low pulmonary volumes. Two groups of moderately trained runners, one using hypoventilation (HYPO, n=7) and one control group (CONT, n=8), were constituted. The training consisted in performing 12 sessions of 55 min within 4 weeks. In each session, HYPO ran 24 min at 70% of maximal O(2) consumption ( [V(02max)) with a breath holding at functional residual capacity whereas CONT breathed normally. A V(02max) and a time to exhaustion test (TE) were performed before (PRE) and after (POST) the training period. There was no change in V(O2max), lactate threshold or TE in both groups at POST vs. PRE. At maximal exercise, blood lactate concentration was lower in CONT after the training period and remained unchanged in HYPO. At 90% of maximal heart rate, in HYPO only, both pH (7.36+/-0.04 vs. 7.33+/-0.06; p<0.05) and bicarbonate concentration (20.4+/-2.9 mmolL(-1) vs. 19.4+/-3.5; p<0.05) were higher at POST vs. PRE. The results of this study demonstrate that VH training did not improve endurance performance but could modify the glycolytic metabolism. The reduced exercise-induced blood acidosis in HYPO could be due to an improvement in muscle buffer capacity. This phenomenon may have a significant positive impact on anaerobic performance.