Brain oxygenation declines in elite Kenyan runners during a maximal interval training session.

PURPOSE: The purpose of this study was to characterise the cerebral oxygenation (Cox) response during a high-intensity interval training session in Kenyan runners, and to examine any relationship with running performance. METHODS: 15 Kenyan runners completed a 5-km time trial (TT) and a Fatigue Training Test on a treadmill (repeated running bouts of 1-km at a pace 5% faster than their mean 5-km TT pace with a 30-s recovery until exhaustion). Changes in Cox were monitored via near-infrared spectroscopy through concentration changes in oxy- and deoxy-haemoglobin (Δ[O2Hb] and Δ[HHb]), tissue oxygenation index (TOI), and total hemoglobin index (nTHI). RESULTS: The number of 1-km repetitions achieved by the participants was 5.5 ± 1.2 repetitions at a mean pace of 20.5 ± 0.7 km h-1. Δ[O2Hb] measured at the end of each running repetition declined progressively over the course of the trial (p = 0.01, ES = 4.59). Δ[HHb] increased during each running bout until the end of the Fatigue Training Test (p < 0.001; ES = 6.0). TOI decreased significantly from the beginning of the test (p = 0.013, ES = 1.83), whereas nTHI remained stable (ES = 0.08). The Cox decline in the Fatigue Training Test was negatively correlated with the speed at which the test was completed (p = 0.017; r = -0.61), suggesting that the best performers were able to defend their Cox better than those of lower running ability. CONCLUSIONS: In conclusion, this study suggests that elite Kenyan runners cannot defend cerebral oxygenation when forced to exercise to their physiological limits. This emphasises the critical importance of pacing in their racing success.

Are gait characteristics and ground reaction forces related to energy cost of running in elite Kenyan runners?

The aim of this study was to determine whether gait cycle characteristics are associated with running economy in elite Kenyan runners. Fifteen elite Kenyan male runners completed two constant-speed running sets on a treadmill (12 km ·h-1 and 20 km ·h-1). VO2 and respiratory exchange ratio values were measured to calculate steady-state oxygen and energy cost of running. Gait cycle characteristics and ground contact forces were measured at each speed. Oxygen cost of running at different velocities was 192.2 ± 14.7 ml· kg-1· km-1 at 12 km· h-1 and 184.8 ± 9.9 ml· kg-1· km-1 at 20 km· h-1, which corresponded to a caloric cost of running of 0.94 ± 0.07 kcal ·kg-1·km-1 and 0.93 ± 0.07 kcal· kg-1· km-1. We found no significant correlations between oxygen and energy cost of running and biomechanical variables and ground reaction forces at either 12 or 20 km· h-1. However, ground contact times were ~10.0% shorter (very large effect) than in previously published literature in elite runners at similar speeds, alongside an 8.9% lower oxygen cost (very large effect). These results provide evidence to hypothesise that the short ground contact times may contribute to the exceptional running economy of Kenyan runners.

C34T mutation of the AMPD1 gene in an elite white runner.

The case is reported of an elite, male, white endurance runner (28 years of age), who is one of the best non-African runners in the world despite carrying the C34T mutation in the gene (AMPD1) that encodes the skeletal muscle specific isoform of AMP deaminase, an enzyme that plays an important role in muscle metabolism. The frequency of the mutant allele in sedentary white people is 8-11%. Previous research has shown that this mutation, at least in homozygotes, can impair the exercise capacity of untrained people and their trainability. The maximum oxygen uptake of the study subject was exceptionally high (83.6 ml/kg/min), whereas his ammonia and lactate concentrations at high submaximal running speeds were lower than those of other world class runners who are not carriers of the mutation. The partial metabolic deficiency of the study subject is possibly compensated for by his exceptionally favourable anthropometric characteristics (body mass index 18.2 kg/m2).

Prevalence of diabetes and impaired glucose tolerance in Aragón, Spain.

OBJECTIVE: To determine the prevalence of diabetes and impaired glucose tolerance (IGT) and to investigate their associated cardiovascular risk factors in Aragón, Spain. RESEARCH DESIGN AND METHODS: We performed a population-based cross-sectional study with stratified and purposive sampling of residents aged 10-74 years. A sample of 935 subjects (427 men and 508 women) was selected. All except those with a previous history of diabetes underwent an oral glucose tolerance test (OGTT), and World Health Organization (WHO) criteria were used for diagnosis of undiagnosed diabetes and IGT. Plasma lipid levels, blood pressure, BMI, and waist-to-hip ratio were also measured. RESULTS: The prevalence of diagnosed and undiagnosed diabetes and IGT was 3.1, 3.0, and 7.2%, respectively. In the age range of 30-64 years, the age-adjusted prevalence of diabetes (using the world population of Segi) was 7.1% in men and 5.6% in women. Both diabetes and IGT were associated with high blood pressure, high triglyceride levels, low HDL cholesterol levels, and overweight and upper-body fat distribution. Only upper-body fat distribution in women was significantly higher in subjects with diabetes than in subjects with IGT. CONCLUSIONS: The prevalence of diabetes in Aragón was moderately high (6.1%) and comparable with that reported in other white populations around the world. The proportion of unknown cases of diabetes was nearly 50%. Cardiovascular risk factors associated with diabetes and IGT supported the existence of an insulin resistance or metabolic syndrome, but there were not sufficient differences between diabetes and IGT to suggest a possible pathogenetic relation of hyperinsulinemia and associated risk factors.

Maintained cerebral oxygenation during maximal self-paced exercise in elite Kenyan runners.

The purpose of this study was to analyze the cerebral oxygenation response to maximal self-paced and incremental exercise in elite Kenyan runners from the Kalenjin tribe. On two separate occasions, 15 elite Kenyan distance runners completed a 5-km time trial (TT) and a peak treadmill speed test (PTS). Changes in cerebral oxygenation were monitored via near-infrared spectroscopy through concentration changes in oxy- and deoxyhemoglobin (Δ[O2Hb] and Δ[HHb]), tissue oxygenation index (TOI), and total hemoglobin index (nTHI). During the 5-km TT (15.2 ± 0.2 min), cerebral oxygenation increased over the first half (increased Δ[O2Hb] and Δ[HHb]) and, thereafter, Δ[O2Hb] remained constant (effect size, ES = 0.33, small effect), whereas Δ[HHb] increased until the end of the trial (P < 0.05, ES = 3.13, large effect). In contrast, during the PTS, from the speed corresponding to the second ventilatory threshold, Δ[O2Hb] decreased (P < 0.05, ES = 1.51, large effect), whereas Δ[HHb] continued to increase progressively until exhaustion (P < 0.05, ES = 1.22, large effect). Last, the TOI was higher during the PTS than during the 5-km TT (P < 0.001, ES = 3.08; very large effect), whereas nTHI values were lower (P < 0.001, ES = 2.36, large effect). This study shows that Kenyan runners from the Kalenjin tribe are able to maintain their cerebral oxygenation within a stable range during a self-paced maximal 5-km time trial, but not during an incremental maximal test. This may contribute to their long-distance running success.

Increased plasma pancreastatin-like immunoreactivity levels in non-obese patients with essential hypertension.

DESIGN: Pancreastatin, a novel peptide, is known to inhibit insulin secretion and to have a glycogenolytic effect, and is present in many endocrine and chromaffin cells. Both the plasma insulin levels and the adrenergic activity accompanying insulin resistance have been shown to be increased in hypertensive subjects. Our working hypothesis was that pancreastatin might play a role in these pathological phenomena. METHODS: We studied the plasma pancreastatin level in non-obese essential hypertensive patients in response to an intravenous glucose load. We further measured the responses to the glucose challenge of insulin, glucagon, catecholamines and free fatty acids, as well as other factors related to insulin resistance (i.e. lipoproteins and apolipoproteins). We separated the hypertensive patients into three groups according to their response to an oral glucose-tolerance test: normoinsulinaemic, hyperinsulinaemic and glucose-intolerant. Matched normotensive control subjects were also studied. RESULTS: Pancreastatin levels did not change in the control group after the glucose challenge. However, all hypertensive patients showed an increase in plasma pancreastatin levels after glucose loading. The normoinsulinaemic hypertensive patients also had elevated basal pancreastatin levels. The increase in pancreastatin levels was in the ranking: normoinsulinaemic > hyperinsulinaemic > glucose-intolerant. The pancreastatin: insulin ratio showed that the secretion of pancreastatin and insulin may be regulated differently. Basal free fatty acid and glucagon levels were found to be elevated both in the hyperinsulinaemic and in the glucose-intolerant group. Fasting triglycerides levels were increased in all of the hypertensive patients. Other risk factors for coronary artery disease were also found to be altered: elevated very low-density lipoprotein-cholesterol and decreased high-density lipoprotein-cholesterol, with ranking: normoinsulinaemic < hyperinsulinaemic < glucose-intolerant. CONCLUSIONS: These results show an increase in pancreastatin levels in hypertensive patients, suggesting that pancreastatin might play a role in the pathophysiology of essential hypertension.

Normal pancreastatin-like and increased post-glucose insulin levels in young offspring of insulin-resistant non-obese essential hypertensive patients.

Pancreastatin is a regulatory peptide known to inhibit insulin secretion and insulin action with a glycogenolytic effect in the liver. This peptide is present in and secreted by many endocrine and chromaffin cells. Abnormalities of glucose, insulin and lipoprotein metabolism are common in patients with hypertension, as well as their first-degree relatives. We have recently studied a group of non-obese hypertensive subjects in which pancreastatin-like levels were increased compared with controls, and correlated with norepinephrine levels. We hypothesized that pancreastatin alongside the sympathoadrenal system might have a part in the insulin resistance of these patients, and this metabolic syndrome could play a role in the pathogenesis and complications of hypertension. In this article, we studied the normotensive offspring of these nonobese hypertensive patients and looked for metabolic abnormalities as well as plasma pancreastatin, glucagon and catecholamine levels. The subjects were separated into two groups: (1) offspring from non-insulin-resistant patients and (2) offspring from insulin-resistant patients. We found that after an intravenous glucose load, offspring from insulin-resistant patients were already hyperinsulinemic, although glucose clearance was normal, suggesting an early alteration in insulin sensitivity, whereas pancreastatin and catecholamine levels were normal compared with matched controls. However, offspring from non-insulin-resistant patients had no differences with controls. These results suggest that pancreastatin and catecholamines may not play an important role in triggering insulin resistance, although they may be important once the syndrome is established.

Regression of left ventricular hypertrophy in patients with essential hypertension. Results of 6 month treatment with indapamide.

Left ventricular hypertrophy (LVH) is a major risk factor for cardiovascular morbidity in hypertensive patients. The effects of diuretics on LVH have raised controversies, but recent studies suggest that diuretics are able to reduce LVH in hypertensive patients, mainly through a reduction in ventricular diameter. The present multicenter open study was designed to test the effects of indapamide, a widely used nonthiazide diuretic, on LVH in patients with essential hypertension. Patients had to have mild-to-moderate essential hypertension (supine diastolic blood pressure [sDBP] 95 to 115 mm Hg) with echocardiographic evidence of LVH (left ventricular mass index [LVMI] > 130 g/m2 for men and > 110 g/m2 for women). After a 2 week placebo run-in period, eligible patients underwent a 6 month treatment with 2.5 mg indapamide daily. All echograms were performed by the same investigator before and after 6 months of indapamide. Clinical and biological acceptability and quality of life (visual analog scale) were also studied. One hundred and thirty patients were included in the study and 112 completed the trial. Indapamide induced a significant reduction i systolic and diastolic blood pressures. Indapamide induced a marked reduction in posterior wall thickness (from 12.1 +/- 2.0 to 11.2 +/- 1.6 mm) and in interventricular wall thickness (from 12.7 +/- 1.7 to 11.8 +/- 1.9 mm; each P < .001) and a slight decrease in left ventricular diameter (P = .049). This resulted in a 13% reduction in LVMI (from 161.9 +/- 37.9 to 140.7 +/- 33.8 g/m2, P < .001). Left ventricular fractional shortening remained unchanged. There was no significant relation between changes in LVMI and changes in systolic, diastolic, or mean blood pressure. No significant adverse clinical or biological effects were reported during the study. The increased score of the visual analog scale indicated that overall well-being was improved (P < .001). Our study indicates that indapamide, in addition to blood pressure control, is able to reduce LVH. This effect was achieved mainly through a reduction in wall thicknesses rather than in internal cavity diameter.

Comparison of the antihypertensive effects of the fixed dose combination enalapril 10 mg/nitrendipine 20 mg vs losartan 50 mg/hydrochlorothiazide 12.5 mg, assessed by 24-h ambulatory blood pressure monitoring, in essential hypertensive patients.

Fixed combinations of calcium channel blockers and angiotensin converting enzyme inhibitors represent an alternative to diuretic-based combination therapy. The aim of the present study was to compare the antihypertensive efficacy of the combination enalapril 10 mg/nitrendipine 20 mg (E/N) vs losartan 50 mg/hydrochlorothiazide 12.5 mg (L/H), assessed by 24-h ambulatory blood pressure monitoring. This multicentre, double-blind, parallel study included 97 hypertensive patients (office diastolic blood pressure (DBP) 90-109 mmHg and daytime DBP > 85 mmHg). After a 2- to 3-week period of single-blind placebo, they were randomized to receive double-blind treatment with E/N (n = 48) or L/H (n = 49) for a 4-week period. The primary outcome measure was the difference in 24-h DBP reduction between treatments from randomization to the end of the double-blind period. Secondary efficacy variables included differences in 24-h systolic (S) BP reduction, daytime, night-time and office SBP and DBP reduction, proportion of responders and controlled patients, trough-to-peak ratio and smoothness indexes. Safety was assessed by the proportion of patients with adverse events and the detection of laboratory abnormalities. No significant differences were observed in the primary outcome measure. The group receiving E/N tended to show greater reductions in most measures (24 h, daytime and office SBP and DBP) and higher BP control rates, but only the difference in the rate of office SBP control (< 140 mmHg) reached statistical significance (42.2 vs 22.4%; P = 0.048). The trough-to-peak ratios and smoothness indexes were similar in both groups. The incidence of adverse events related to the treatment was 27.1% (95% CI 14.5-39.6%) in E/N-treated patients and 14.3% (95% CI 4.5-45.8%) in the L/H group, but differences were not significant. The kind of event more frequently observed were flushing and headache in E/N, and dizziness and asthenia in L/H; all observed adverse events were mild. We conclude that E/N and L/H have a similar antihypertensive efficacy, assessed by office or ambulatory blood pressure monitoring. E/N achieved a significantly higher office SBP control rate, but this was accompanied by an apparently higher proportion of mild adverse events.

Yield point in prediction of compressive behavior of lumbar vertebral body by dual-energy x-ray absorptiometry.

The aims of the present study were to evaluate the influence of bone mineral content (BMC) and density on the behavior of the lumbar vertebra during compression and to determine critical points during compression. Dual-energy X-ray absorptiometry (DXA) and compression tests were performed on 44 vertebral bodies obtained from 22 cadavers. The results of the study indicate that bone mineral content measured by DXA were strongly correlated with ultimate failure load (r = 0.53, p < 0.001), ultimate failure stress (r = 0.581, p < 0.001), and toughness (r = 0.632, p < 0.001). Correlation with the yield point (r = 0.543, p < 0.001) was also significant. Bone mineral density showed similar results with ultimate failure load (r = 0.742, p < 0.001), ultimate failure stress (r = 0.742, p = 0.001), toughness (r = 0.673, p < 0.001), and yield point (r = 0.693, p < 0.001). The correlation between elastic parameters and DXA were suggestive but not quite significant. BMC was not related significantly with stiffness or Young's modulus. There was no correlation between bone mass and vertebral deformation parameters. In conclusion, bone mass and bone density appear to have a clear relationship to ultimate parameters and yield point. The relation with the yield point might be critical because it marks the beginning of the plastic region and signals the appearance of the first trabecular fractures.

[Radioactive phosphorus uptake test in ophthalmology]. / Test de captation du phosphore radio-actif en ophtalmologie.

The ophthalmology radioactive phosphorus uptake test has been utilized in the differential diagnosis of intra ocular lesions in 21 patients. In the majority of the cases the diagnosis was histologically confirmed. When the lesion is located in the anterior part of the globe, it is not necessary to make an incision of the conjunctiva to perform the test. If the lesion is located in the posterior segment, the test is performed by the transscleral route, with surgical incision of the conjunctiva and with indirect ophthalmoscopy control when possible. In 3 patients with choroidal hemangioma were results false-positives, observed with inferior P32 uptake to that in patients with choroidal melanomas. One false-negative result was obtained in a patient with a clinical diagnosis of uveal malignant melanoma, histologically confirmed after enucleation of the globe. In all others patients with uveal malignant melanoma results were highly positive.

[Importance of morphostructural changes observed in cortical micro-vessels in patients who died after a severe head injury]. / Relevancia de las alteraciones morfoestructurales detectadas en la microvascularización de la corteza cerebral en pacientes fallecidos por traumatismo craneoencefálico grave.

INTRODUCTION: The development of secondary lesions in traumatic head injuries seems to be a determinative factor for the survival of these patients. Endothelium damage of cortical microvessels could be fundamental in the main secondary lesions as cerebral ischemia and intracranial hypertension. OBJECTIVES: To investigate which are the main morphological changes that can be observed in cortical microvessels from these patients. MATERIAL AND METHODS: We have studied 15 fresh human brains from subjects died after a severe head injury. The study has been carried out by scanning electron microscopy of vascular corrosion casts and confocal microscopy of histological sections after immunocytochemistry, as well as detection of apoptosis by TUNEL technique. RESULTS AND CONCLUSIONS: The most significant structural alterations were observed mainly on arterioles and capillaries of the middle and deep vascular zones of the cerebral cortex. Corrosion casts showed vessels with longitudinal folds, sunken surface with craters and flattened vessels with reduced lumen. Histological sections immunostained with MAS-336 also showed vessels with longitudinal folds and thinning of their vascular lumen, the presence of cytoplasmic round bodies and a thickening of endothelial cell membrane. TUNEL method revealed a positive staining of some endothelial cells. The structural alterations observed seem to reveal a situation of cellular damage of endothelium in the human cortical microvessels from these patients. It can be thought that this kind of lesions, as well as the secondary functional injury of the blood brain barrier, could play an important role in the development of secondary damage.

[Urinary continence after radial prostatectomy. Prognostic factors and recovery time]. / Continencia urinaria tras prostatectomía radical. Factores pronósticos y tiempo de recuperación.

OBJECTIVES: To assess the urinary continence after radical prostatectomy and its evolution over time. To analyse possible prognosis factors. MATERIAL AND METHODS: We have reviewed 101 patients that have undergone radical prostatectomy. We define "continent patient" as that one who doesn't require any type of urinary protection. By means of Kaplan-Meier method, we evaluate the recovery of continence along time. We analyze potential conditional factors (age, stage, surgery technique, surgery experience,...). The statistical tools used are: chi-square, Fisher, Cox regression, T-test and Kaplan-Meier. RESULTS: Median monitoring time: 27.33 months. 80% are continent patients, 48.7% of which reach maximum continence before the 3rd, month is due and 17.5% after the 6 months (2.5% between 9-12 months). Their probability of becoming "continents" during the first 4 months es 0.4692. patients under 70 years old recover continence before those who are over 70 years old (medians: 3.51 months and 5.67 months respectively, p = 0.0211). CONCLUSIONS: The recovery of continence takes place progressively and a 17.5% of patients reach plain recovery in the 6-12 months period after surgery. The evaluation of the surgery treatment to correct incontinence should consider the possibility of "spontaneous" recovery in a 2.5% of patients in the 9-12 months period after surgery. Age affects negatively the recovery time; it is significantly less for patients under 70.

[Central serous choroidopathy. Long term study]. / Coroidopatía central serosa. Estudio a largo plazo.

PURPOSE: To investigate the demographic characteristics, clinical findings and long-term outcome of central serous chorioretinopathy (CSC). METHODS: This study examined retrospectively the clinical stories and fluorescein angiographies of 113 patients with CSC and a minimum follow-up of 12 months. RESULTS: A total of 113 patients was examined; 90 were men and 23 women. Bilateral involvement was found in 13 cases. In 85.7% of the eyes (Group I) resolution was completed in months and mean final visual acuity (VA) was 79.3/100, while 14.3% of the eyes (Group II) showed a chronic evolution, with diffuse retinal pigment epithelipathy and mean final VA of 47.2/100. The mean age of the patients in Group II was significantly higher; male:female ratio was also higher in this Group. Bilateral involvement occurred in 6% of patients from Group I and in 46.6% in Group II. CONCLUSIONS: Chronic CSC affected less than 15% of the patients. Mean age in this group of patients was higher than in patients with a classic CSC, most of the cases were men, bilateral involvement was present in nearly 50% of the cases and 50% of them suffered a significant visual permanent impairment.

[Effect of the treatment with amlodipine on left ventricular hypertrophy in hypertensive patients]. / Efecto del tratamiento con amlodipino sobre la hipertrofia ventricular izquierda en pacientes hipertensos.

BACKGROUND: Left ventricular hypertrophy (LVH) is one of the physiopathological effects of hypertension and one of the main risk factors for sudden death, myocardial infarction and congestive heart failure. Drugs to treat hypertension must not only reduce blood pressure, but also modify the facts which lead to ventricular hypertrophy. This study has been designed to assess the effect of amlodipine, a calcium-antagonist, on LVH in hypertensive patients. METHODS: 20 hypertensive patients (mild to moderate, both sexes, mean age 45.0 yr) were included in a single-blind study. After an initial, four weeks placebo period, active treatment was given (amlodipine 5 mg a day). Dose titration was made after 4-8 weeks to 10 mg a day if necessary and continued until the end of the study. Systolic (SBP) and diastolic blood pressure (DBP), as well as pulse rate (PR) and adverse events were recorded at every visit. Blood and urine analysis, catecholamine, plasmatic renin activity and Mode M echocardiography were made at the beginning and the end of the study. RESULTS: Only one patient was excluded. SBP and DBP showed a significantly fall (p < 0.001). In 80% of patients DBP fell under 90 mm Hg. Every echocardiographic parameter, but left ventricular diastolic dimension, showed significantly reductions at the end of the study: septum thickness (p = 0.001), posterior wall thickness (p = 0.001), left ventricular systolic dimension (p = 0.014), wall relative thickness (p = 0.015), shortening fraction (p = 0.009), left ventricular mass (p = 0.001) and corrected left ventricular mass (p = 0.001). Blood parameters did not modify. CONCLUSIONS: Amlodipine has a beneficial effect on LVH and also is an effective and safe drug to treat mild to moderate hypertension.

[Intestinal calcium and vitamin D absorption in essential arterial hypertension]. / Absorción intestinal de calcio y vitamina D en la hipertensión arterial esencial.

The intestinal absorption of calcium and seric levels of calcifediol and calcitriol were studied in 27 patients with essential blood hypertension (BH) and 20 normal patients in a control group. The hypertensive patients were divided in three groups depending on the plasmatic renin activity (PRA), (high, normal, low). We found a significantly higher rate of intestinal calcium absorption in the group of patients with BH and low PRA than in the control group (22.73 +/- 19.05 and 10.7 +/- 17.13% respectively) (p less than 0.025). The seric levels of calcitriol (1,25 (OH) 2D3) were significantly higher in the group of patients with hypertension and low PRA than in the control group (48.16 +/- 5.25 and 33.13 +/- 2.9 pg/ml respectively) (p less than 0.025). The seric levels of calcifediol (25-OH-D3) were significantly lower in low PRA patients than those patients in the control group (12.37 +/- 2.44 and 21.94 +/- 2.82 ng/ml respectively) (p less than 0.025). We concluded that patients with essential blood hypertension and low PRA have significantly lower calcitriol levels than any other group, probably conditioning the greater intestinal calcium absorption shown in this group.

[Comparative study of soft diet or clear liquids in the resumption of oral intake in the postoperative period]. / Análisis comparativo entre reinstalar la vía oral en el postoperatorio con dieta blanda o líquidos claros.

BACKGROUND: The reinstitution of oral intake in patients who have undergone intraabdominal surgery has traditionally progressed in a stepwise fashion beginning with clear liquids, liquid diet and after an adequate tolerance regular diet. OBJECTIVE: To determine if the reinstitution of oral intake after major abdominal surgery with regular diet offers benefits into which it's not harmful for patients and reduce the in-hospital stay. TYPE OF STUDY: Prospective, randomized, open study conducted between October 1996 to May 1997. MATERIAL AND METHODS: Patients aged 18 and older submitted to elective or urgent surgery of the abdomen and pelvis were included with the exception of: bariatric surgery, esophageal resection, pyloroplasty, pancreato-duodenal resection, laparoscopic surgery and patients under ventilatory support or with enteral or parenteral nutrition. As soon as postoperative ileus disappeared patients were randomly assigned to receive regular diet (group 1) or clear liquids (group 2) as the first oral intake. Oral diet tolerance was evaluated as well as the caloric and protein intake, the in-hospital stay and the cost. RESULTS AND MEASUREMENTS: Group 1 was conformed by 63 patients, and group 2 for 69 patients. There was no difference between, sex, age, kind of surgery (elective or emergency) and the type of pathology. 96.6% of patients in group 1 tolerated regular diet and 96.9% of patients in group 2 tolerated clear liquids. Only two patients of each group required oral intake suspension. The in-hospital stay was 2.6 +/- 2.0 days in group 1 against 3.4 +/- 2.6 in group 2 (P = < 0.005), the cost of the in-hospital stay period after the beginning of oral intake was 2726 +/- 2107 pesos in group 1 against 3547 +/- 2690 in group 2 (P = < 0.005), the caloric and protein intake were 1307 +/- 523 Kcals with 55.9 +/- 23.2 grams of proteins in group 1 and 651 +/- 204 Kcals and 0 grams of proteins in group 2 (P = < 0.00001). CONCLUSIONS: No difference was found in adverse reactions with the use of regular diet as the first meal. The in-hospital stay and the cost were reduced significantly and the calories and grams of proteins are higher in group 1. These results suggest that the routine use of clear liquids as the initial postoperative diet may be unnecessary and nutritionally suboptimal when compared with regular diet.