The effect of exercise on gastric mucosal energy status has not been fully elucidated. The aim of this study was to evaluate the impact of submaximal cycling on gastric mucosal energy balance and its relationship to changes in systemic energy status. Ten healthy volunteers (age 20-40 years) were investigated at rest (BL), during 30 min of submaximal exercise (E) on bicycle ergometry and during the 30 min after the completion of cycling. Gastric mucosal PCO(2) ( P(gm)CO(2)) was measured by air tonometry at 10-min intervals and the gastric mucosal-arterial PCO(2) difference ( PCO(2)gap) was calculated. Hemodynamics, arterial blood gases, lactate and pyruvate were also measured. PCO(2)gap significantly increased throughout exercise [BL: 0.2 kPa (median), -0.1-0.6 kPa (25th-75th percentiles); E(10 min): 1.0 kPa, 0.8-1.7 kPa; E(20 min): 1.35 kPa, 0.8-1.8 kPa; E(30 min): 1.5 kPa, 0.9-2.0 kPa]. The early changes in PCO(2)gap ( PCO(2)gap at E(10 min) minus PCO(2)gap at BL) correlated significantly and positively with corresponding changes in arterial lactate ( r(2)=0.58, P<0.05) and lactate-to-pyruvate ratio ( r(2)=0.72, P<0.05). On recovery, all metabolic parameters normalized within 30 min. We conclude that submaximal cycling in volunteers leads to the early derangement of gastric mucosal energy balance. The time course of PCO(2)gap parallels changes in systemic energy status.

• MeSH
• Exercise physiology   MeSH
• Adult MeSH
• Energy Metabolism physiology   MeSH
• Blood Pressure physiology   MeSH
• Lactic Acid metabolism   MeSH
• Pyruvic Acid metabolism   MeSH
• Humans MeSH
• Carbon Dioxide blood   MeSH
• Splanchnic Circulation physiology   MeSH
• Heart Rate physiology   MeSH
• Gastric Mucosa blood supply   metabolism   MeSH
• Exercise Test MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Male MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Lactic Acid MeSH
• Pyruvic Acid MeSH
• Carbon Dioxide MeSH

The authors evaluate the long-term fate of 1,254 conservatively treated patients suffering from ischaemic heart disease (IHD), in dependence on the results of submaximal ECG exercise test and coronary angiography. Survival rate was closely related to the heart rate achieved during exercise, the duration of exercise, presence or absence of subjective or ECG signs of coronary insufficiency during exercise, and on the degree of impairment of coronary circulation. Comparison of invasively and non-invasively obtained data confirms that submaximal ECG exercise test can contribute to a more accurate assessment of prognosis in patients with double- or triple-vessel coronary heart disease.

• MeSH
• Angiography * MeSH
• Electrocardiography MeSH
• Coronary Angiography * MeSH
• Coronary Disease diagnosis   diagnostic imaging   mortality   MeSH
• Middle Aged MeSH
• Humans MeSH
• Follow-Up Studies MeSH
• Prognosis MeSH
• Exercise Test * MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

BACKGROUND: Aortic stiffening and reduced nitric oxide (NO) availability may contribute to the pathophysiology of heart failure with preserved ejection fraction (HFpEF). OBJECTIVES: This study compared indices of arterial stiffness at rest and during exercise in subjects with HFpEF and hypertensive control subjects to examine their relationships to cardiac hemodynamics and determine whether exertional arterial stiffening can be mitigated by inorganic nitrite. METHODS: A total of 22 hypertensive control subjects and 98 HFpEF subjects underwent hemodynamic exercise testing with simultaneous expired gas analysis to measure oxygen consumption. Invasively measured radial artery pressure waveforms were converted to central aortic waveforms by transfer function to assess integrated measures of pulsatile aortic load, including arterial compliance, resistance, elastance, and wave reflection. RESULTS: Arterial load and wave reflections in HFpEF were similar to those in control subjects at rest. During submaximal exercise, HFpEF subjects displayed reduced total arterial compliance and higher effective arterial elastance despite similar mean arterial pressures in control subjects. This was directly correlated with higher ventricular filling pressures and depressed cardiac output reserve (both p < 0.0001). With peak exercise, increased wave reflections, impaired compliance, and increased resistance and elastance were observed in subjects with HFpEF. A subset of HFpEF subjects (n = 52) received sodium nitrite or placebo therapy in a 1:1 double-blind, randomized fashion. Compared to placebo, nitrite decreased aortic wave reflections at rest and improved arterial compliance and elastance and central hemodynamics during exercise. CONCLUSIONS: Abnormal pulsatile aortic loading during exercise occurs in HFpEF independent of hypertension and is correlated with classical hemodynamic derangements that develop with stress. Inorganic nitrite mitigates arterial stiffening with exercise and improves hemodynamics, indicating that arterial stiffening with exercise is at least partially reversible. Further study is required to test effects of agents that target the NO pathway in reducing arterial stiffness in HFpEF. (Study of Exercise and Heart Function in Patients With Heart Failure and Pulmonary Vascular Disease [EXEC]; NCT01418248. Acute Effects of Inorganic Nitrite on Cardiovascular Hemodynamics in Heart Failure With Preserved Ejection Fraction; NCT01932606. Inhaled Sodium Nitrite on Heart Failure With Preserved Ejection Fraction; NCT02262078).

• Keywords
• HFpEF, aortic stiffness, exercise, heart failure, hypertension,
• MeSH
• Exercise physiology   MeSH
• Nitrates pharmacology   MeSH
• Double-Blind Method MeSH
• Ventricular Function, Left physiology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Rest physiology   MeSH
• Prospective Studies MeSH
• Aged MeSH
• Heart Failure drug therapy   physiopathology   MeSH
• Stroke Volume physiology   MeSH
• Vascular Stiffness physiology   MeSH
• Exercise Test MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Randomized Controlled Trial MeSH
• Names of Substances
• Nitrates MeSH
• sodium nitrate MeSH Browser

The exercise-induced increase and post-exercise decrease of plasma hyaluronan concentration were studied in human subjects. Six well trained men performed incremental exercise until exhaustion (MAX), intensive (submaximal, SUB) and extensive exercise (moderate, MOD) on a bicycle ergometer, defined as work at 100, 77 and 50% of maximal oxygen consumption. Hyaluronan was analyzed using a high-sensitivity, proteoglycan-dependent time-resolved immunoassay and hemoglobin, hematocrit and plasma protein levels were assessed using standard laboratory procedures. Compared to resting control levels, the plasma hyaluronan concentration (pHA) increased (p < 0.05) by 76% (65.0 +/- 6.1 vs. 37.0 +/- 1.0 microg/l) during 15 min MAX, by 44% (56.4 +/- 2.6 vs. 39.2 +/- 3.8 microg/l) during 30 min SUB and by 27% (46.3 +/- 7.8 vs. 36.4 +/- 4.3 microg/l) during 90 min MOD. The increase with time averaged 4.03%.min(-1) during MAX, 1.35%.min(-1) during SUB and 0.35%.min during MOD. After exercise (15 and 30 min), pHA decreased by 43% below resting levels after MAX (p < 0.05) and by 36% after SUB, respectively. In conclusion, pHA steadily rose with time during physical exertion, with a non-linear increase of concentration/time slope with exercise intensity; second, the magnitude of the post-exercise pHA decrease was proportional to the exercise-induced pHA increase, suggesting elevated hyaluronan clearance with rising plasma levels after physical exertion.

• MeSH
• Exercise physiology   MeSH
• Adult MeSH
• Blood Volume MeSH
• Hyaluronic Acid biosynthesis   blood   MeSH
• Humans MeSH
• Lymph physiology   MeSH
• Exercise Test MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Male MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Hyaluronic Acid MeSH

BACKGROUND: A warmup period of priming exercise has been shown to improve peripheral oxygen transport in older adults. We sought to determine the acute effects of priming exercise on central hemodynamics at rest and during a repeat exercise in heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS: This is a post hoc analysis from 3 studies. Patients with HFpEF (n = 42) underwent cardiac catheterization with simultaneous expired gas analysis at rest and during exercise (20 W for 5 minutes, priming exercise). Measurements were then repeated at rest and during a second bout of exercise at a 20-W workload (second exercise). During the priming exercise, patients with HFpEF displayed dramatic increases in biventricular filling pressures and exercise-induced pulmonary hypertension. After the priming exercise at rest, biventricular filling pressures and pulmonary artery (PA) pressures were lower and lung tidal volume was increased. During the second bout of exercise, biventricular filling (PA wedge pressure, 29 ± 8 mm Hg at second exercise vs 32 ± 7 mm Hg at first exercise, P = .0003) and PA pressures were lower, and PA compliance increased. CONCLUSIONS: This study shows that short duration, submaximal priming exercise attenuates the pathologic increases in filling pressures, improving pulmonary vascular hemodynamics at rest and during repeat exercise in patients with HFpEF.

• Keywords
• Hemodynamics, diastolic function, exercise, heart failure,
• MeSH
• Ventricular Function, Left MeSH
• Hemodynamics MeSH
• Humans MeSH
• Aged MeSH
• Heart Failure * therapy   MeSH
• Stroke Volume MeSH
• Exercise Tolerance MeSH
• Exercise Test MeSH
• Check Tag
• Humans MeSH
• Aged MeSH
• Publication type
• Journal Article MeSH

In the evaluation of the general functional fitness and/or work capacity of subjects for the purpose of exercise diagnostics, physical fitness enhancement in untrained healthy subjects or sportsmen and exercise rehabilitation of patients, two types of ergometers are generally used: a bicycle ergometer and a treadmill. To facilitate the conversion of results of functional examinations made in the laboratory to field conditions, where, as a rule, physical activity is performed, the intensity of exercise assessed on the bicycle ergometer must be converted to that on a treadmill and vice versa. Measurements on a bicycle ergometer and treadmill in differently trained groups of men can be supplemented with data from the literature to develop a general equation which relates exercise intensity on the bicycle ergometer P (W.kg-1) and running speed on the treadmill v (km.h-1) as v = 3.544.P +/- 0.625. In the submaximal range of exercise intensities (20-80% of maximal aerobic power) this relationship is independent on the training status, age, body weight, strength and speed capacity of the subjects examined. The above equation may be used in the submaximal exercise intensity range with a maximum error of about 12% or less.

• MeSH
• Energy Metabolism MeSH
• Adaptation, Physiological MeSH
• Humans MeSH
• Oxygen Consumption MeSH
• Physical Education and Training MeSH
• Physical Fitness physiology   MeSH
• Exercise Test * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH

In order to describe the kinetics of the reaction of the heart rate (HR) to the onset of exercise of constant intensity, the half-time (t1/2) of HR can be used. First in a study of exercise of intensity corresponding to 2 W kg-1 on a cycle ergometer, the t1/2 in 15 trained male rowers and 11 untrained male students was determined. In the trained subjects t1/2 was smaller than in untrained students, mean (+/- S.D.) values being 24.10 (+/- 3.36) s and 47.12 (+/- 4.08) s respectively. In both groups t1/2 was positively correlated with resting HR, r = 0.774 and 0.846 and negatively correlated with maximal oxygen uptake (VO2max), r = -0.728 and -0.871 respectively (P less than 0.01). The regulation of HR in the transition range was concluded to be very similar to the regulation of VO2 and energy requirements. The second part of this work was concerned with responses to graded exercise. The linearity of the HR-exercise intensity relationship is maintained up to a submaximal exercise intensity beyond which the increase in exercise intensity exceeds the increase in HR. It was hypothesized that the point where HR departs from linearity in an incremental exercise test may be employed as a predictor of the ventilatory threshold (Tvent). To examine this, 28 trained male long-distance runners were tested on a treadmill and 17 untrained young male subjects were tested on a cycle ergometer using a continuous incremental protocol. The Tvent was determined from the dependence of VE on VO2 and/or VCO2. The VO2, HR and exercise intensity at Tvent were compared with the same parameters determined from the dependence of HR on exercise intensity. No significant differences were found between Tvent and HR break point levels. It was concluded from this second study that the HR break point level coincides with Tvent.

• MeSH
• Running MeSH
• Adult MeSH
• Adaptation, Physiological * MeSH
• Kinetics MeSH
• Humans MeSH
• Respiratory Function Tests MeSH
• Sports MeSH
• Oxygen Consumption MeSH
• Heart Rate * MeSH
• Physical Exertion * MeSH
• Exercise Test MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Publication type
• Journal Article MeSH

IMPORTANCE: Impaired exercise capacity is a cardinal manifestation of obstructive hypertrophic cardiomyopathy (HCM). The Phase 3 Trial to Evaluate the Efficacy and Safety of Aficamten Compared to Placebo in Adults With Symptomatic Obstructive HCM (SEQUOIA-HCM) is a pivotal study characterizing the treatment effect of aficamten, a next-in-class cardiac myosin inhibitor, on a comprehensive set of exercise performance and clinical measures. OBJECTIVE: To evaluate the effect of aficamten on exercise performance using cardiopulmonary exercise testing with a novel integrated measure of maximal and submaximal exercise performance and evaluate other exercise measures and clinical correlates. DESIGN, SETTING, AND PARTICIPANTS: This was a prespecified analysis from SEQUOIA-HCM, a double-blind, placebo-controlled, randomized clinical trial. Patients were recruited from 101 sites in 14 countries (North America, Europe, Israel, and China). Individuals with symptomatic obstructive HCM with objective exertional intolerance (peak oxygen uptake [pVO2] ≤90% predicted) were included in the analysis. Data were analyzed from January to March 2024. INTERVENTIONS: Randomized 1:1 to aficamten (5-20 mg daily) or matching placebo for 24 weeks. MAIN OUTCOMES AND MEASURES: The primary outcome was change from baseline to week 24 in integrated exercise performance, defined as the 2-component z score of pVO2 and ventilatory efficiency throughout exercise (minute ventilation [VE]/carbon dioxide output [VCO2] slope). Response rates for achieving clinically meaningful thresholds for change in pVO2 and correlations with clinical measures of treatment effect (health status, echocardiographic/cardiac biomarkers) were also assessed. RESULTS: Among 282 randomized patients (mean [SD] age, 59.1 [12.9] years; 115 female [40.8%], 167 male [59.2%]), 263 (93.3%) had core laboratory-validated exercise testing at baseline and week 24. Integrated composite exercise performance improved in the aficamten group (mean [SD] z score, 0.17 [0.51]) from baseline to week 24, whereas the placebo group deteriorated (mean [SD] z score, -0.19 [0.45]), yielding a placebo-corrected improvement of 0.35 (95% CI, 0.25-0.46; P <.001). Further, aficamten treatment demonstrated significant improvements in total workload, circulatory power, exercise duration, heart rate reserve, peak heart rate, ventilatory efficiency, ventilatory power, and anaerobic threshold (all P <.001). In the aficamten group, large improvements (≥3.0 mL/kg per minute) in pVO2 were more common than large reductions (32% and 2%, respectively) compared with placebo (16% and 11%, respectively). Improvements in both components of the primary outcome, pVO2 and VE/VCO2 slope throughout exercise, were significantly correlated with improvements in symptom burden and hemodynamics (all P <.05). CONCLUSIONS AND RELEVANCE: This prespecified analysis of the SEQUOIA-HCM randomized clinical trial found that aficamten treatment improved a broad range of exercise performance measures. These findings offer valuable insight into the therapeutic effects of aficamten. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05186818.

• MeSH
• Double-Blind Method MeSH
• Cardiomyopathy, Hypertrophic * physiopathology   drug therapy   MeSH
• Middle Aged MeSH
• Humans MeSH
• Aged MeSH
• Oxygen Consumption physiology   MeSH
• Cardiac Myosins MeSH
• Exercise Tolerance * physiology   MeSH
• Exercise Test * methods   MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Clinical Trial, Phase III MeSH
• Multicenter Study MeSH
• Randomized Controlled Trial MeSH
• Names of Substances
• Cardiac Myosins MeSH

The aim of this study was to assess the effects of increasing specific (paddling ergometer) and non-specific (cycle ergometer) exercise on parameters relating to the ventilatory threshold (Th(vent)) and work efficiency in 11 young female flat-water kayakists. When these trained subjects were tested using non-specific workloads, their oxygen uptake (VO2) values at Th(vent), as a percentage of VO2max (%VO2max), were close to those of untrained subjects [74.2 (5.6) % VO2max, mean (SD)]. However, when we tested the same subjects using specific exercise, we recorded values typical of highly trained athletes [84.8 (4.7) % VO2max). For the non-specific exercise on the cycle ergometer, we recorded work efficiency values close to those of untrained subjects [22.3 (2.5) %]; however, for the specific exercise on the paddling ergometer, we recorded much lower values [13.4 (3.0) %] both at the level of Th(vent). The work efficiency at two warm-up submaximal exercise loads on the paddling ergometer was non-significantly lower than values at Th(vent) [12.3 (2.8) % and 12.9 (2.9) % respectively]. Significant correlations were found between maximal-performance VO2 (ml.kg-1.min-1) and performance at Th(vent) during paddling and race performance (0.623, 0.630 and 0.648 respectively, all P < 0.05). Because the results of both specific and non-specific submaximal exercise tests are different, we suggest caution in the interpretation of physiological variables that may be sensitive to training status. The evaluation of Th(vent) and work efficiency as supplementary parameters during laboratory studies enables the determination of the effectiveness of the training process and the specific adaptation of the subjects.

• MeSH
• Exercise physiology   MeSH
• Bicycling physiology   MeSH
• Work of Breathing physiology   MeSH
• Adaptation, Physiological MeSH
• Humans MeSH
• Respiratory Mechanics physiology   MeSH
• Adolescent MeSH
• Sports physiology   MeSH
• Oxygen Consumption physiology   MeSH
• Physical Education and Training MeSH
• Exercise Test MeSH
• Check Tag
• Humans MeSH
• Adolescent MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

The purpose of the study was to evaluate non-invasively the response of the isovolumic relaxation period to different types of exercise--dynamic supine bicycle exercise (DSBE) and handgrip (HGP), in a selected healthy population. From simultaneous echo-polygraphic recordings, obtained in 30 young subjects at rest, during submaximal DSBE, during one minute of HGP (75% of maximal heart rate) and in the recovery period, the true isovolumic relaxation period (IRP) was determined. Systolic (SBP) and diastolic (DBP) blood pressure, aortic closing pressure (AoCP) and heart rate (HR) were also recorded. HR increased more markedly in DSBE (delta HR = +85% at peak load) than in HGP (delta HR = +29% at peak), while a greater rise of DBP (delta DBP = +25%) was observed in HGP. IRP shortened at both exercises as the workload progressively increased, with a maximum decrease by 54% in DSBE and by 42% in HGP. Moreover, at both exercises, an exponential correlation between IRP and HR was found. Correlating IRP with HR and AoCP by multiple regression analysis, it was found that IHP in HGP was equally affected by HR and AoCP, while during DSBE heart rate had a greater influence than AoCP.

• MeSH
• Adult MeSH
• Isometric Contraction * MeSH
• Myocardial Contraction * MeSH
• Humans MeSH
• Adolescent MeSH
• Muscle Contraction * MeSH
• Exercise Test * MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Adolescent MeSH
• Male MeSH
• Publication type
• Journal Article MeSH