J. Drigny

EFFECT OF INTERVAl TRAININg ON COgNITIVE FUNCTIONINg AND CEREBRAl OxygENATION IN OBESE PATIENTS: A PIlOT STUDy

OBJECTIVE To assess the effect of a 4-month high-intensity interval training programme on cognitive functioning, cerebral oxygenation, central haemodynamic and cardiometabolic parameters and aerobic capacity in obese patients. METHODS Cognitive functioning, cerebral oxygenation, central haemodynamic, cardiometabolic and exercise para-meters were measured before and after a 4-month high-intensity interval training programme in 6 obese patients (mean age 49 years (standard deviation 8), fat mass percentage 31 ± 7%). RESULTS Body composition (body mass, total and trunk fat mass, waist circumference) and fasting insulin were improved after the programme (p < 0.05). V. O2 and power output at ventilatory threshold and peak power output were improved after the programme (p < 0.05). Cognitive functioning, including short-term and verbal memory, attention and processing speed, was significantly improved after training (p < 0.05). Cerebral oxygen extraction was also improved after training (p < 0.05). CONCLUSION These preliminary results indicate that a 4-month high-intensity interval training programme in obese patients improved both cognitive functioning and cere-bral oxygen extraction, in association with improved exercise capacity and body composition.

Long-term high-intensity interval training associated with lifestyle modifications improves QT dispersion parameters in metabolic syndrome patients

BACKGROUND QT dispersion (QTd) is a marker of myocardial electrical instability, and is increased in metabolic syndrome (MetS). Moderate intensity continuous exercise (MICE) training was shown to improve QTd in MetS patients. OBJECTIVES To describe long-term effects of MICE and high-intensity interval exercise training (HIIT) on QTd parameters in MetS. METHODS Sixty-five MetS patients (53 ± 9 years) were assigned to either a MICE (60% of peak power output [PPO]), or a HIIT program (alternating phases of 15-30 s at 80% of PPO interspersed by passive recovery phases of equal duration), twice weekly during 9 months. Ventricular repolarization indices (QT dispersion=QTd, standard deviation of QT = sdQT, relative dispersion of QT = rdQT, QT corrected dispersion = QTcd), metabolic, anthropometric and exercise parameters were measured before and after the intervention. RESULTS No adverse events were noted during exercise. QTd decreased significantly in both groups (51 vs 56 ms in MICE, P < 0.05; 34 vs 38 ms in HIIT, P < 0.05). Changes in QTd were correlated with changes in maximal heart rate (r = -0.69, P < 0.0001) and in heart rate recovery (r = -0.49, P < 0.01) in the HIIT group only. When compared to MICE, HIIT training induced a greater decrease in weight, BMI and waist circumference. Exercise capacity significantly improved by 0.82 and 1.25 METs in MICE and HIIT groups respectively (P < 0.0001). Lipid parameters also improved to the same degree in both groups. CONCLUSION In MetS, long-term HIIT and MICE training led to comparable effects on ventricular repolarization indices, and HIIT might be associated with greater improvements in certain cardiometabolic risk factors.

Muscle VO2 and forearm blood flow repeatability during venous and arterial occlusions in healthy and coronary heart disease subjects

This study aims were: 1) to assess forearm blood flow (FBF) and muscle oxygen consumption (mVO2) repeatability assessed with near-infra red spectroscopy (NIRS) during venous occlusions (VO) in middle aged healthy subjects and patients with stable coronary heart disease (CHD), 2) to assess the agreement between mVO2 calculated from NIRS signals during VO and arterial occlusion (AO) in 18 middle aged healthy subjects and 12 patients with CHD. FBF and mVO2 were measured using NIRS during 2 successive VO (1-min duration), followed by a 5-min AO. Repeatability for FBF and mVO2 during VO was assessed with intra class correlation (ICC), coefficient of variation (CV %) and agreement between VO and AO mVO2 was assessed with a Bland and Altman analysis. FBF and mVO2 during VO were highly reproducible in healthy (FBF: ICC 0.73, CV% 9.75; mVO2: ICC 0.89, CV% 12.6) and CHD subjects (FBF: ICC 0.95, CV% 10.26; mVO2: ICC 0.98, CV% 7.92). VO and AO mVO2 were in agreement in healthy (mean bias: 0.002 mL O2.min-1.100g-1) and CHD subjects (mean bias: 0.014 mL O2.min-1.100g-1). FBF and mVO2 measured with NIRS during VO and/or AO are highly reproducible methods to assess microvascular function in healthy subjects and stable CHD patients.

Cognitive function in patients with stable coronary heart disease: Related cerebrovascular and cardiovascular responses

Chronic exercise has been shown to prevent or slow age-related decline in cognitive functions in otherwise healthy, asymptomatic individuals. We sought to assess cognitive function in a stable coronary heart disease (CHD) sample and its relationship to cerebral oxygenation-perfusion, cardiac hemodynamic responses, and V˙O2 peak compared to age-matched and young healthy control subjects. Twenty-two young healthy controls (YHC), 20 age-matched old healthy controls (OHC) and 25 patients with stable CHD were recruited. Cognitive function assessment included short term—working memory, perceptual abilities, processing speed, cognitive inhibition and flexibility and long-term verbal memory. Maximal cardiopulmonary function (gas exchange analysis), cardiac hemodynamic (impedance cardiography) and left frontal cerebral oxygenation-perfusion (near-infra red spectroscopy) were measured during and after a maximal incremental ergocycle test. Compared to OHC and CHD, YHC had higher V˙O2 peak, maximal cardiac index (CI max), cerebral oxygenation-perfusion (ΔO2 Hb, ΔtHb: exercise and recovery) and cognitive function (for all items) (P<0.05). Compared to OHC, CHD patients had lower V˙O2 peak, CI max, cerebral oxygenation-perfusion (during recovery) and short term—working memory, processing speed, cognitive inhibition and flexibility and long-term verbal memory (P<0.05). V˙O2 peak and CI max were related to exercise cerebral oxygenation-perfusion and cognitive function (P<0.005). Cerebral oxygenation-perfusion (exercise) was related to cognitive function (P<0.005). Stable CHD patients have a worse cognitive function, a similar cerebral oxygenation/perfusion during exercise but reduced one during recovery vs. their aged-matched healthy counterparts. In the all sample, cognitive functions correlated with V˙O2 peak, CI max and cerebral oxygenation-perfusion.

Long-term lifestyle intervention and optimized high intensity interval training program improve body composition, cardiovascular risk and exercise capacity in obese patients with or without metabolic syndrome

bjectives.– To evaluate the feasibility at rest with reproducibility of the ntra-operator and inter-operator measurement of CO and to compare with easurements obtained by transthoracic echocardiography (TTE). To estimate he feasibility during effort and during the recovery effort. To determine the iagnostic, therapeutic and prospective implication. ethods.– Observational study based on 142 consecutive outpatients included rom cardiac rehabilitation (CHU Dijon). IGR was performed before and/or uring and/or after the cardiac stress test by photoacoustic analysis using two nert gases: 0.5% nitrous oxide and 0.1% sulfur hexafluoride (indirect oxyen Fick Method Innocor®). Statistical analysis based on correlation analysis, land and Altman, and standardization. esults.– At rest, the correlation coefficient was 0.91 (P< 0.001) between two O in intra-operator in 26 patients, 0.89 (P< 0.001) between two CO in interperator in 30 patients, 0.38 (P= 0.039) between the CO measured by IGR and TE in 30 patients. Using the method of Bland and Altman, the range of variation f repeatability was respectively± 27%, ± 33%± 42%. During the effort in 45 atients, formulas of standardization were used to assess components: stroke olume (SV) and heart rate (HR). Two populations were isolated: preferential ncrease in SV or HR. onclusion.– At rest, feasibility, repeatability and reproducibility of the meaurements are correct (despite the dispersion related to measurement of CO). t submaximal exercise, feasibility is good. The measurement to quantify the emodynamic changes during rehabilitation is valid and applicable in various athological conditions (heart failure in high CO at rest, etc), and could help to dapt the use of chronotopic drug. eferences 1] Goda A et al. Usefulness of non-invasive measurement of cardiac output uring sub-maximal exercise to predict outcome in patients with chronic heart ailure. AM J Cardiol 2009; 104(Suppl. 11):1556–60. 2] Follath F. Challenging the dogma of high target doses in the treatment of eart failure: is more always better? Arch Cardiovasc Dis 2009;102:785–9.

260: Cognitive performance, cerebral oxygenation, exercise capacity and cardiac output in patients with coronary heart disease

Objectives Recent data suggested that coronary heart disease (CHD) is associated with non-amnesic mild cognitive impairment. Our purpose was to assess cognitive performances at rest, VO2max, cardiac output (CO), and cerebral hemodynamic changes during maximal exercise in patients with stable CHD. Methods 22 stable fit CHD patients (70,9±9,3 years), 10 healthy age-matched (68,6±8,6 years), 10 middle aged controls and 10 young controls ( Results There was no intergroup difference in VO2max or maximal CO between cardiac and healthy age-matched individuals. Some cognitive tests, especially for executive functioning, were significantly better for the healthy matched group (Trail Making Test-B; Inhibition/Flexibility Stroop Task and Backward Digit Span, p differences were observed with lower amplitudes in HHb signalss for less fit subjects. In control groups, middle aged and young subjects had significant higher performances in VO2max, most of cognitive tests and higher amplitudes changes for NIRS indices while exercising. Conclusion Despite comparable maximal exercise tolerances and CO, CHD individuals presented reduced cognitive performances compared to healthy age-matched subjects. We evidenced an inter-individual variability among CHD patients for cerebral NIRS signals changes, especially with age and fitness. These results suggest that variations in HHb are much more related to exercise capacity than O2Hb in CHD patients.