Rupture of the papillary muscle after percutaneous transvenous mitral commissurotomy (PTMC)--a case report

We experienced a rare case of the mitral regurgitation due to papillary muscle rupture after percutaneous transvenous mitral commissurotomy (PTMC). This case was a seventy years old female who underwent PTMC. The cardiac tamponade and mitral regurgitation occurred after PTMC. Pericardial drainage was done immediately, and the next day the emergency operation was required. Rupture of the posterior papillary muscle was found at the operation, and mitral valve replacement was performed. Her postoperative course was uneventful and she discharged on the 26th day after the operation. We should take the papillary muscle rupture into consideration if there are severe sub-valvular lesion and shorting of the chorda.     

Effects of percutaneous balloon mitral valvuloplasty and exercise training on the kinetics of recovery oxygen consumption after exercise in patients with mitral stenosis

AIMS: Kinetics of recovery oxygen consumption after exercise plays an important role in determining exercise capacity. This study was performed to assess the kinetics of recovery oxygen consumption in mitral stenosis and evaluate the effects of percutaneous balloon mitral valvuloplasty and exercise training on the kinetics. METHODS AND RESULTS: Thirty patients with mitral stenosis (valve area < or =1.0 cm2) and same sized age- and size-matched healthy volunteers were included for this study. All subjects performed maximal upright graded bicycle exercise. Thirty consecutive patients who underwent successful percutaneous balloon mitral valvuloplasty (valve area > or =1.5 cm2 and mitral regurgitation grade < or =2), were randomized to an exercise training group or non-training group. The exercise group performed daily exercise training for 3 months. Half-recovery time of peak oxygen consumption was significantly delayed in mitral stenosis as compared to normal subjects (120+/-42 s vs 59+/-5, P<0.01). Peak oxygen consumption (ml x min(-1) x kg(-1)) was significantly increased in both the training (16.8+/-4.9 to 25.3+/-6.9) and non-training groups (16.3+/-5.1 to 19.6+/-6.0) 3 months after percutaneous balloon mitral valvuloplasty. Half-recovery time of peak oxygen consumption was significantly shortened in the training group (124+/-39 to 76+/-13, P<0.01), but not in the non-training group (114+/-46 to 109+/-44 s, P=0.12) at 3 months follow-up. The degrees of symptomatic improvement after percutaneous balloon mitral valvuloplasty were more closely correlated with the changes of the half-recovery time of peak oxygen consumption than those of peak oxygen consumption. CONCLUSION: Kinetics of recovery oxygen consumption was markedly delayed in mitral stenosis, which was improved after exercise training but not after percutaneous balloon mitral valvuloplasty alone. These results suggest that adjunctive exercise training may be useful for improvement of recovery kinetics and subjective symptoms after percutaneous balloon mitral valvuloplasty.     

Effect of moderate hyperglycaemia on left-ventricular systolic time intervals during submaximal exercise of steady workload in healthy subjects

The effect of submaximal exercise at steady workload on left-ventricular systolic time intervals (STI) was studied in healthy subjects. In group I (22 subjects) 20% glucose solution was injected intravenously in a dose of 2.5 ml/kg of body weight before the exercise. In group II (20 subjects) the same exercise was preceded by intravenous injection of normal saline 2.5 ml/kg of body weight. The left ventricular systolic time intervals were determined by the polycardiographic metod of Blumberger modified by Holldack and Weissler. It was found that glucose administration before the exercise improved myocardial contractility during the exercise. During hyperglycaemia the secondary impairment of myocardial contractility was less pronounced than in the control group. Postexercise changes in left ventricular systolic function regressed more rapidly in the group receiving glucose than in controls.     

Prediction of blood lactate accumulation from excess CO2 output during constant exercise

To determine the predictability of blood lactate accumulation from excess CO2 output derived from bicarbonate buffering of lactic acid during constant exercise, eight normal active volunteers were studied during three stages of constant exercise on a cycle ergometer. Three work rates consisted of 100% (stage I), 120% (stage II) and 150% (stage III) of each subject's anaerobic threshold (AT), each of which was lasted for 4 min. Excess CO2 output (Ex CO2, ml) at each stage of constant exercise was estimated form the integral of difference between total VCO2 and aerobic VCO2 (from regression line for VCO2 and VO2 at exercise intensities below the AT obtained in incremental exercise test). Ex CO2 per body mass (Ex CO2-mass-1) was increased progressively with blood lactate (La) accumulation from rest to each stage of constant exercise. Mean values (+/-SD) in the measured La accumulation (delta La,measured) and predicted La accumulation (delta La,predicted) at three stages of constant exercise were 1.82 +/- 0.83 vs 3.19 +/- 1.70 for stage 1, 5.58 +/- 3.47 vs 7.09 +/- 3.28 for stage II and 12.19 +/- 2.36 vs 12.74 +/- 1.83 mmol.l-1 for stage III, respectively. There was a significant difference between delta La,measured and delta La,predicted at stage I (p < 0.05), but no significant differences between these two variables at stage II and III. The averaged difference from delta La,predicted to delta La,measured at stage III (0.55 mmol.l-1) showed a tendency to be smaller than stage I (1.38 mmol.l-1) and II (1.50 mmol.l-1). On the other hand, delta La,predicted was found to correlate very closely with delta La,measured (r = 0.954, P < 0.001, n = 20). The results of this study suggest that the changes of La accumulation could be predicted from excess CO2 output generated in constant exercises above the AT.     

Muscle oxygenation kinetics measured by near-infrared spectroscopy during recovery from exercise in chronic heart failure

The aim of the present study was to determine the kinetics of recovery of muscle oxygenation (MO) from comparable levels of exercise in chronic heart failure (CHF) patients and normal subjects and to relate MO kinetics to the level of exercise intolerance. The rationale is based on the observation that the O2 debt is increased in patients with heart failure and repayment of the debt is relatively slow. Ten patients with stable CHF (mean age 47 +/- 10 years) and nine healthy control subjects (47 +/- 6 years) were studied. All patients had ischemic cardiomyopathy (ejection fraction 33 +/- 7%). On different days, all subjects performed an upright incremental cycle ergometer exercise test with gas-exchange analysis to determine peak VO2, and a 6-minute constant work-rate (CWR) protocol at 60% of peak VO2. Oxygenation of the vastus lateralis muscle was continuously monitored during exercise and recovery using near-infrared spectroscopy (NIRS). Both MO and VO2 responses to recovery were described by a monoexponential model with a time delay. The time constant and time delay were combined to calculate a mean response time (MRT). Recovery VO2 and MO MRTs for the incremental and constant work rate exercise test were longer in CHF patients than in control subjects (p < 0.05). Both VO2 and MO MRTs were inversely related to peak VO2 (r = -0.73 and -0.52, respectively; p < 0.05 for both). However, both kinetics were not significantly different within each group between the two exercise intensities. In conclusion, the greater the cardiac dysfunction, as assessed by peak VO2, the more the recovery of muscle and total body oxygenation from both maximal and submaximal exercise is delayed.     

Effect of ventilation distribution on aerosol bolus dispersion and recovery

It has been speculated that convective ventilatory inhomogeneities are an important factor influencing aerosol bolus behavior in the compromised lung. Multiple-breath 133Xe washout (MBWXe) is a commonly accepted test of ventilation distribution. By comparing aerosol bolus parameters to MBWXe in 9 healthy subjects and 14 cystic fibrosis patients with mild-to-moderate airway obstruction, we have attempted to discern the effect of altered ventilation distribution on aerosol bolus dispersion and recovery. Aerosol boluses (150-ml width) were delivered to the volumetric penetrations of 250 and 500 ml. Similar tidal volumes (approximately 1.25 liters) and flow rates (0.4 l/s) were used for aerosol bolus and MBWXe maneuvers. Associations between bolus parameters and ventilation distribution were only observed in the cystic fibrosis patients. We conclude that aerosol bolus dispersion and recovery are both influenced by convective ventilatory inhomogeneities induced by airway obstruction in these patients.     

Four-year follow-up of patients undergoing percutaneous balloon mitral commissurotomy. A report from the National Heart, Lung, and Blood Institute Balloon Valvuloplasty Registry

OBJECTIVES: This study reports the long-term outcome of patients undergoing percutaneous balloon mitral commissurotomy who were enrolled in the National Heart, Lung, and Blood Institute (NHLBI) Balloon Valvuloplasty Registry. BACKGROUND: The NHLBI established the multicenter Balloon Valvuloplasty Registry in November 1987 to assess both short- and long-term safety and efficiency of percutaneous balloon mitral commissurotomy. METHODS: Between November 1987 and October 1989, 736 patients > or = 18 years old underwent percutaneous balloon mitral commissurotomy at 23 registry sites in North America. The maximal follow-up period was 5.2 years. RESULTS: The actuarial survival rate was 93 +/- 1% (mean +/- SD), 90 +/- 1.2%, 87 +/- 1.4% and 84 +/- 1.6% at 1, 2, 3 and 4 years, respectively. Eighty percent of the patients were alive and free of mitral surgery or repeat balloon mitral commissurotomy at 1 year. The event-free survival rate was 80 +/- 1.5% at 1 year, 71 +/- 1.7% at 2 years, 66 +/- 1.8% at 3 years and 60 +/- 2.0% at 4 years. Important univariable predictors of actuarial mortality at 4 years included age > 70 years (51% survival), New York Heart Association functional class IV (41% survival) and baseline echocardiographic score > 12 (24% survival). Multivariable predictors of mortality included functional class IV, higher echocardiographic score and higher postprocedural pulmonary artery systolic and left ventricular end-diastolic pressures (p < 0.01). CONCLUSIONS: Percutaneous balloon mitral commissurotomy has a favorable effect on the hemodynamic variables of mitral stenosis, and long-term follow-up data suggest that it is a viable alternative with respect to surgical commissurotomy in selected patients.     

Exchangeability of actin in cardiac myocytes and fibroblasts as determined by fluorescence photobleaching recovery

OBJECTIVE: To assess whether hypertension is a risk factor for hysterectomy performed for benign diseases. METHODS: Self-report questionnaires were collected from 77% of 2301 Danish women aged 30, 40, 50, or 60 years selected at random in 1982 for a prevalence study. Information about cardiovascular diseases, hypertension, use of medicine, weight and dieting history, life-styles, psychologic factors, gynecologic history (including history of hysterectomy), and social background were recorded. Weight, height, and blood pressure were measured. In an incidence study, the cohort was followed during 1982-1990 via central registers to assess the incidence of hysterectomy. Logistic and Cox regressions were used to analyze data. RESULTS: In the prevalence study, history of hypertension partly explained the relation between hysterectomy and cardiovascular diseases. In the incidence study, history of hypertension and use of diuretics were significant risk factors for hysterectomy. After confounder control, use of diuretics was explained by weight-related variables, and hypertension was a risk factor for hysterectomy in educated women (adjusted relative risk [RR] 2.88, 95% confidence interval [CI] 1.07, 7.76) and in women with weight fluctuations (adjusted RR 3.31, 95% CI 1.35, 8.14). Weight cycling and lack of education remained significant risk factors for hysterectomy in women with and without hypertension, respectively. CONCLUSION: History of hypertension, weight cycling, and lack of education are closely related risk factors for premenopausal hysterectomy. These three risk factors contribute to women undergoing hysterectomy having an increased risk for cardiovascular diseases. We proposed that hypertension might be a plausible biological cause of menorrhagia and an indication for hysterectomy.     

Effect of altered vision on constant load exercise performance while wearing a respirator

Previous testing has shown that visual acuity greatly influences task performance at light work rate levels. At moderate to heavy work rates, however, the Performance Rating Table (PRT) predicts almost no visual acuity effect. This experiment was performed to determine if the PRT value is realistic. Ten subjects walked on a treadmill at 75-80% of their maximum heart rates until their voluntary end points. Subjects wore various masks of the same kind, each with a different set of clouded lenses. Visual acuities, as measured on the Snellen eye chart, were measured before, during, and after exercise. It was found that visual acuity did not influence performance time, and that an average value for a performance rating of 91 must have been influenced by other mask factors besides visual acuity. These other factors are most likely respiratory stress, thermal stress, and other vision elements. The full-facepiece masks used in this study adversely affected visual acuity by about three-quarters of a Snellen line during exercise. Postexercise visual acuities were found to first decrease below pre-exercise values, then become better than pre-exercise values, then decline asymptotically to pre-exercise values.     

Effects of cardiac output on blood and tissue pH during general anesthesia with constant ventilation

We investigated the effects of cardiac output on blood and tissue pH in 106 adult patients undergoing cardiac or non-cardiac surgery under general anesthesia. After anesthetic induction, the minute ventilation volume was kept constant at 10 ml.kg-1 x 10 cycles.min-1. A pulmonary artery catheter and a nasogastric tube incorporating a tonometer were inserted. During surgery, cardiac index (CI), pH, Pco2, BE, So2 and Hb of arterial and mixed venous blood as well as gastric intramucosal pH (pHi) were measured simultaneously. Oxygen uptake index (Vo2I) and blood CO2 contents were calculated. The measurements were repeated every 10 to 20 minutes during surgery or during the prebypass period. Two patients with preoperative cardiogenic shock were excluded from data analysis because of development of severe acidosis and 624 sets of data from 104 patients were analyzed. Arterial and mixed venous pH correlated negatively with CI. Blood Pco2 and base excess (BE) correlated positively and negatively, respectively, with CI. Blood lactate concentration measured 142 times in the last 30 patients correlated positively with CI. Vo2I correlated positively with CI and Paco2 correlated positively with Vo2I. Veno-arterial differences in Pco2 and Cco2 correlated negatively with CI. Due to the difference, Caco2 correlated positively with CI, while Cvco2 did not correlate with CI. pHi correlated negatively with CI but only marginally. By multiple regression analysis, pHi was not affected significantly by CI, while it showed positive correlation with pHa, Hb, Sao2 and negative correlation with blood temperature. When cardiac output increased, blood pH decreased due to increased Pco2 and decreased BE. An increase in Paco2 might result from both an increase in Vo2 or Vco2 and decreased ventilation-to-perfusion ratio. A decrease in BE might result from increased washout of acids (e.g. lactate) from the tissue to the central circulation. In contrast to blood pH, pHi or tissue pH was not affected significantly by cardiac output unless patients were in cardiogenic shock.     

Effect of theophylline on substrate metabolism during exercise

We tested the hypothesis that adenosine is involved in regulating substrate metabolism during exercise. Seven trained cyclists were studied during 30 minutes of exercise at approximately 75% maximal oxygen uptake (VO2max). Lipid metabolism was evaluated by infusing [2H5]glycerol and [1-13C]palmitate, and glucose kinetics were evaluated by infusing [6,6-2H]glucose. Fat and carbohydrate oxidation were also measured by indirect calorimetry. The same subjects performed two identical exercise tests, but in one trial theophylline, a potent adenosine receptor antagonist, was infused for 1 hour before and throughout exercise. Theophylline did not increase whole-body lipolysis (glycerol rate of appearance [Ra]) or free fatty acid (FFA) release during exercise, but fat oxidation was lower than control values (9.5 +/- 3.0 v 18.0 +/- 4.2 micromol x min(-1) x kg(-1), P < .01). Glucose Ra was not affected by theophylline infusion, but glucose uptake was lower (31.6 +/- 4.1 v 40.4 +/- 5.0 micromol x min(-1) x kg(-1), P < .05) and glucose concentration was higher (6.4 +/- 0.6 v 5.8 +/- 0.4 mmol/L, P < .05) than in the control trial. Total carbohydrate oxidation (302.3 +/- 26.2 v 265.5 +/- 11.7 micromol x min(-1) x kg(-1), P < .06), estimated muscle glycogenolysis (270.7 +/- 23.1 v 225.1 +/- 9.7 micromol x min(-1) x kg(-1), P < .05), and plasma lactate concentration (7.9 +/- 1.6 v 5.9 +/- 1.1 mmol/L, P < .001) were also higher during the theophylline trial. These data suggest that adenosine may play a role in stimulating glucose uptake and restraining glycogenolysis but not in limiting lipolysis during exercise.     

Effect of supplemental oxygen on supramaximal exercise performance and recovery in cystic fibrosis

The effects of supplemental O2 on recovery from supramaximal exercise and subsequent performance remain unknown. If recovery from exercise could be enhanced in individuals with chronic lung disease, subsequent supramaximal exercise performance could also be improved. Recovery from supramaximal exercise and subsequent supramaximal exercise performance were assessed after 10 min of breathing 100% O2 or room air (RA) in 17 cystic fibrosis (CF) patients [25 +/- 10 (SD) yr old, 53% men, forced expired volume in 1 s = 62 +/- 21% predicted] and 17 normal subjects (25 +/- 8 yr old, 59% men, forced expired volume in 1 s = 112 +/- 15% predicted). Supramaximal performance was assessed as the work of sustained bicycling at a load of 130% of the maximum load achieved during a graded maximal exercise. Peak minute ventilation (VE) and heart rate (HR) were lower in CF patients at the end of each supramaximal bout than in controls. In CF patients, single-exponential time decay constants indicated faster recovery of HR (tau HR = 86 +/- 8 and 73 +/- 6 s in RA and O2, respectively, P < 0.01). Similarly, fast and slow time constants of two-exponential equations providing the best fit for ventilatory recovery were improved in CF patients during O2 breathing (tau 1VE = 132.1 +/- 10.5 vs. 82.5 +/- 10.4 s; tau 2VE = 880.3 +/- 300.1 vs. 368.6 +/- 107.1 s, P < 0.01). However, no such improvements occurred in controls. Supramaximal performance after O2 improved in CF patients (109 +/- 6% of the 1st bout after O2 vs. 94 +/- 6% in RA, P < 0.01). O2 supplementation had no effect on subsequent performance in controls (97 +/- 3% in O2 vs. 93 +/- 3% in RA). We conclude that supplemental O2 after a short bout of supramaximal exercise accelerates recovery and preserves subsequent supramaximal performance in patients with CF.     

次亚磷酸盐在电解铜氰废液同时回收铜和氰过程中的作用

以高浓度铜氰溶液为研究对象,通过添加次亚磷酸盐,进行了高碱条件下电积回收铜与氰化物的研究.研究了次亚磷酸盐用量、温度对铜和氰化物沉积过程的影响;利用线性循环伏安、恒电位电解并结合X射线衍射分析阳极沉淀物的物相,分析了阳极反应机理和次亚磷酸盐抑制氰化物分解的机理;采用电解后余液进行金的氰化浸出实验.结果表明：次亚磷酸盐可有效抑制电沉积过程中氰化物的分解,其抑制效果随温度升高而增强.电解过程中阳极表面生成的Cu²⁺是造成氰化物分解的主要原因;次亚磷酸盐通过优先与Cu²⁺发生氧化还原反应从而抑制氰化物的分解.处理后余液对金的氰化浸出无不良影响,通过电解可综合回收铜氰废水中金属与氰化物,处理后废水可循环利用.     

Effect of beverage osmolality on intestinal fluid absorption during exercise

To determine how osmolality of an orally ingested fluid-replacement beverage would alter intestinal fluid absorption from the duodenum and/or jejunum during 85 min of cycle exercise (63.3 +/- 0.9% peak O2 uptake) in a cool environment (22 degreesC), seven subjects (5 men, 2 women, peak O2 uptake = 54.5 +/- 3.8 ml . kg-1 . min-1) participated in four experiments separated by 1 wk in which they ingested a water placebo (WP) or one of three 6% carbohydrate (CHO) beverages formulated to give mean osmolalities of 197, 295, or 414 mosmol/kgH2O. CHO solutions also contained 17-18 meq Na+ and 3.2 meq K+. Nasogastric and multilumen tubes were fluoroscopically positioned in the gastric antrum and duodenojejunum, respectively. Subjects ingested a total of 23 ml/kg body mass of the test solution, 20% (370 +/- 9 ml) of this volume 5 min before exercise and 10% (185 +/- 4 ml) every 10 min thereafter. By using the rate of gastric emptying as the rate of intestinal perfusion (G. P. Lambert, R. T. Chang, D. Joensen, X. Shi, R. W. Summers, H. P. Schedl, and C. V. Gisolfi. Int. J. Sports Med. 17: 48-55, 1996), intestinal absorption was determined by segmental perfusion from the duodenum (0-25 cm) and jejunum (25-50 cm). There were no differences (P > 0.05) in gastric emptying (mean 18.1 +/- 1.3 ml/min) or total fluid absorption (802 +/- 109, 650 +/- 52, 674 +/- 62, and 633 +/- 74 ml . 50 cm-1 . h-1 for WP, hypo-, iso-, and hypertonic solutions, respectively) among beverages; but WP was absorbed faster (P < 0.05) from the duodenum than in the jejunum. Of the total volume of fluid ingested, 82 +/- 14, 74 +/- 6, 76 +/- 5, and 68 +/- 7% were absorbed for WP, hypo-, iso-, and hypertonic beverages, respectively. There were no differences in urine production or percent change in plasma volume among solutions. We conclude that total fluid absorption of 6% CHO-electrolyte beverages from the duodenojejunum during exercise, within the osmotic range studied, is not different from WP.     

Effect of fluid ingestion on muscle metabolism during prolonged exercise

Five trained men were studied during 2 h of cycling exercise at 67% peak oxygen uptake at 20-22 degrees C to examine the effect of fluid ingestion on muscle metabolism. On one occasion, the subjects completed this exercise without fluid ingestion (NF) while on the other they ingested a volume of distilled deionized water that prevented loss of body mass (FR). No differences in oxygen uptake during exercise were observed between the two trials. Heart rate was lower (P < 0.01) throughout exercise when fluid was ingested, and rectal temperature after 2 h of exercise was lower (38.0 +/- 0.2 and 38.6 +/- 0.2 degrees C for FR and NF, respectively; P < 0.01), as was muscle (vastus lateralis) temperature (38.5 +/- 0.4 and 39.1 +/- 0.5 degrees C for FR and NF, respectively; P < 0.05). Resting muscle ATP, creatine phosphate, creatine, glycogen, and lactate levels were similar in the two trials, as were the postexercise ATP, creatine phosphate, and creatine levels. In contrast, muscle glycogen was higher (P < 0.05) and muscle lactate was lower (P < 0.05) after 2 h of exercise in FR compared with NF. Net muscle glycogen utilization during exercise was reduced by 16% when fluid was ingested (318 +/- 46 and 380 +/- 53 mmol/kg dry weight for FR and NF, respectively; P < 0.05). These results indicate that fluid ingestion reduces muscle glycogen use during prolonged exercise, which may account, in part, for the improved performance previously observed with fluid ingestion.     

Effect of epinephrine on muscle glycogenolysis during exercise in trained men

To test the hypothesis that an elevation in circulating epinephrine increases intramuscular glycogen utilization, six endurance-trained men performed two 40-min cycling trials at 71 +/- 2% of peak oxygen uptake in 20-22 degrees C conditions. On the first occasion, subjects were infused with saline throughout exercise (Con). One week later, after determination of plasma epinephrine levels in Con, subjects performed the second trial (Epi) with an epinephrine infusion, which resulted in a twofold higher (P < 0.01) plasma epinephrine concentration in Epi compared with Con. Although oxygen uptake was not different when the two trials were compared, respiratory exchange ratio was higher throughout exercise in Epi compared with Con (0.93 +/- 0.01 vs. 0.89 +/- 0.01; P < 0.05). Muscle glycogen concentration was not different when the trials were compared preexercise, but the postexercise value was lower (P < 0.01) in Epi compared with Con. Thus net muscle glycogen utilization was greater during exercise with epinephrine infusion (224 +/- 37 vs. 303 +/- 30 mmol/kg for Con and Epi, respectively; P < 0.01). In addition, both muscle and plasma lactate and plasma glucose concentrations were higher (P < 0.05) in Epi compared with Con. These data indicate that intramuscular glycogen utilization, glycolysis, and carbohydrate oxidation are augmented by elevated epinephrine during submaximal exercise in trained men.     

Effect of hypohydration on gastric emptying and intestinal absorption during exercise

Dehydration and hyperthermia may impair gastric emptying (GE) during exercise; the effect of these alterations on intestinal water flux (WF) is unknown. Thus the purpose of this study was to determine the effect of hypohydration ( approximately 2.7% body weight) on GE and WF of a water placebo (WP) during cycling exercise (85 min, 65% maximal oxygen uptake) in a cool environment (22 degrees C) and to also compare GE and WF of three carbohydrate-electrolyte solutions (CES) while the subjects were hypohydrated. GE and WF were determined simultaneously by a nasogastric tube placed in the gastric antrum and via a multilumen tube that spanned the duodenum and the first 25 cm of jejunum. Hypohydration was attained 12-16 h before experiments by low-intensity exercise in a hot (45 degrees C), humid (relative humidity 50%) environment. Seven healthy subjects (age 26.7 +/- 1.7 yr, maximal oxygen uptake 55.9 +/- 8.2 ml . kg-1 . min-1) ingested either WP or a 6% (330 mosmol), 8% (400 mosmol), or a 9% (590 mosmol) CES the morning following hypohydration. For comparison, subjects ingested WP after a euhydration protocol. Solutions ( approximately 2.0 liters total) were ingested as a large bolus (4.6 ml/kg body wt) 5 min before exercise and as small serial feedings (2.3 ml/kg body wt) every 10 min of exercise. Average GE rates were not different among conditions (P > 0.05). Mean (+/-SE) values for WF were also similar (P > 0.05) for the euhydration (15.3 +/- 1.7 ml . cm-1 . h-1) and hypohydration (18.3 +/- 2.6 ml . cm-1 . h-1) experiments. During exercise after hypohydration, water absorption was greater (P < 0.05) with ingestion of WP (18.3 +/- 2. 6) and the 6% CES (16.5 +/- 3.7), compared with the 8% CES (6.9 +/- 1.5) and the 9% CES (1.8 +/- 1.7). Mean values for final core temperature (38.6 +/- 0.1 degrees C), heart rate (152 +/- 1 beats/min), and change in plasma volume (-5.7 +/- 0.7%) were similar among experimental trials. We conclude that 1) hypohydration to approximately 3% body weight does not impair GE or fluid absorption during moderate exercise when ingesting WP, and 2) hyperosmolality (>400 mosmol) reduced WF in the proximal intestine.