Clinical Practice & Epidemiology in Mental Health, 2015
Motor commands to perform exercise tasks may also induce activation of cardiovascular centres to ... more Motor commands to perform exercise tasks may also induce activation of cardiovascular centres to supply the energy needs of the contracting muscles. Mental stressors per se may also influence cardiovascular homeostasis. We investigated the cardiovascular response of trained runners simultaneously engaged in mental and physical tasks to establish if aerobically trained subjects could develop, differently from untrained ones, nervous facilitation in the brain cardiovascular centre. Methods : Cardiovascular responses of 8 male middle-distance runners (MDR), simultaneously engaged in mental (colour-word interference test) and physical (cycle ergometer exercise) tasks, were compared with those of 8 untrained subjects. Heart rate, cardiac (CI) and stroke indexes were assessed by impedance cardiography while arterial blood pressures were assessed with a brachial sphygmomanometer. Results : Only in MDR simultaneous engagement in mental and physical tasks induced a significant CI increase which was higher (p<0.05) than that obtained on summing CI values from each task separately performed. Conclusion : Aerobic training, when performed together with a mental effort, induced a CI oversupply which allowed a redundant oxygen delivery to satisfy a sudden fuel demand from exercising muscles by utilizing aerobic sources of ATP, thus shifting the anaerobic threshold towards a higher work load. From data of this study it may also be indirectly stated that, in patients with major depressive disorder, the promotion of regular low-intensity exercise together with mental engagement could ameliorate the perceived physical quality of life, thus reducing their heart risk associated with physical stress.
American Journal of Physiology - Heart and Circulatory Physiology, 2015
Patients suffering from obesity and metabolic syndrome (OMS) manifest a dysregulation in hemodyna... more Patients suffering from obesity and metabolic syndrome (OMS) manifest a dysregulation in hemodynamic response during exercise, with an exaggerated systemic vascular increase. However, it is not clear whether this is the consequence of metabolic syndrome per se or whether it is due to concomitant obesity. The aim of the present investigation was to discover whether OMS and noncomplicated obesity resulted in different hemodynamic responses during the metaboreflex. Twelve metabolically healthy but obese subjects (MHO; 7 women), 13 OMS patients (5 women), and 12 normal age-matched controls (CTL; 6 women) took part in this study. All participants underwent a postexercise muscle ischemia protocol to evaluate the metaboreflex activity. Central hemodynamics were evaluated by impedance cardiography. The main result shows an exaggerated increase in systemic vascular resistance from baseline during the metaboreflex in the OMS patients as compared with the other groups (481.6 ± 180.3, -0.52 ± 177.6, and -60.5 ± 58.6 dynes·s(-1)·cm(-5) for the OMS, the MHO, and the CTL groups, respectively; P < 0.05). Moreover, the MHO subjects and the CTL group showed an increase in cardiac output during the metaboreflex (288.7 ± 325.8 and 703.8 ± 276.2 ml/m increase with respect to baseline), whereas this parameter tended to decrease in the OMS group (-350 ± 236.5 ml/m). However, the blood pressure response, which tended to be higher in the OMS patients, was not statistically different between groups. The results of the present investigation suggest that OMS patients have an exaggerated vasoconstriction in response to metaboreflex activation and that this fact is not due to obesity per se.
The aim of the present investigation was to assess the role of aging on the contribution of diast... more The aim of the present investigation was to assess the role of aging on the contribution of diastolic function during metaboreflex activation. In particular, it aimed to determine whether age-related impairment in diastolic function would produce a different hemodynamic response in elderly subjects (EG) as compared to young controls (CTL). Hemodynamic response to metaboreflex activation obtained by post-exercise muscle ischemia (PEMI) was gathered in 22 EG and 20 healthy CTL. Subjects also performed a control exercise recovery (CER) test to compare data from the PEMI test. The main results showed that the EG group reached higher mean arterial blood pressure (MAP) increment than the CTL group during the PEMI test (+11.2 ± 8.6 vs 6.1 ± 6.4 mmHg in the EG and CTL group, respectively). Moreover, the mechanism by which this response was achieved was different between the two groups. In detail, EG reached the target MAP by increasing systemic vascular resistance (+235.2 ± 315.1 vs -44.4 ± 167.7 dynes s(-1) cm(-5) for the EG and the CTL group, respectively), whereas MAP response in the CTL was the result of an increase in cardiac pre-load (-1.5 ± 11.2 vs 14 ± 13.7 ml in end-diastolic volume for the EG and the CTL group, respectively), which led to a rise in stroke volume and cardiac output. Moreover, early filling peak velocities showed a higher response in the CTL than EG group. This study demonstrates that diastolic function is important for normal hemodynamic adjustment during the metaboreflex and to avoid excessive vasoconstriction.
Exercise training for subjects over 65 should be applied to improve quality of life. However, phy... more Exercise training for subjects over 65 should be applied to improve quality of life. However, physiological adaptations are transitory and disappear after training reduction or cessation (Bousquet et all, 2013 - Mujika & Bousquet, 2010). Beside detraining exerts well known effects in young athletes, while limited information is available for elderly individuals. PURPOSE: The aim of this study was to investigate the effects of 8 weeks of detraining in elderly subjects (age > 65 yrs), after 12 weeks of exercise prescription at vigorous intensity. METHODS: 17 healthy participants (69.3 ± 4.3 yrs) performed a randomized controlled trial on training program about 12 weeks at vigorous intensity (range 64-85% of Heart Rate Reserve) followed by 8 weeks of detraining. Before and after the training cessation period, subjects underwent an exercise test on a cycle Ergometer test until exhaustion to assess VO2max. Heart Rate Recovery HRR, Waist-Hip ratio (WHR) and Body Mass Index (BMI) were a...
Exercise training for subjects over 65 should be applied to improve quality of life. However, phy... more Exercise training for subjects over 65 should be applied to improve quality of life. However, physiological adaptations are transitory and disappear after training reduction or cessation (Bousquet et all, 2013 -Mujika & Bousquet, 2010. Beside detraining exerts well known effects in young athletes, while limited information is available for elderly individuals. PURPOSE: The aim of this study was to investigate the effects of 8 weeks of detraining in elderly subjects (age > 65 yrs), after 12 weeks of exercise prescription at vigorous intensity. METHODS: 17 healthy participants (69.3 ± 4.3 yrs) performed a randomized controlled trial on training program about 12 weeks at vigorous intensity (range 64-85% of Heart Rate Reserve) followed by 8 weeks of detraining. Before and after the detraining period, subjects underwent an exercise test on a cycle Ergometer test until exhaustion to assess VO2max. Heart Rate Recovery HRR, Waist-Hip ratio (WHR) and Body Mass Index (BMI) were also assessed. Paired t-test were used to compare the detraining effects on all variables before and after 8 detraining weeks. RESULTS:VO2max decreased by 6,65% during the detraining period (24.2 ± 4.7 to 22.6 ± 4.5 ml/kg/min p=0.32). However, BMI decreased by 5,3% (26.5 ± 3.5 to 25.1 ± 3.9 kg/m2 p = 0.24). Conversely HRR increased by 7% (62.1 ± 8.8 to 67.1 ± 9.2 bpm p=0.15 ) these decrement were not significant. WHR increased significantly by 9% (0.92 ± 0.06 to 1.01 ± 0.09 p<0.05 ) CONCLUSIONS:In the present investigation, after the detraining period following a vigorous training program, subjects were able to maintain a level of VO2max without a negative effect. Training exercise at vigorous intensity, instead of moderate intensity which is more commonly applied, were more positive also for BMI and HRR, otherwise the WHR were significantly different. Previous studies, employing moderate intensity (<64% Heart Rate Reserve) showed high tendencies to return back to the pre-training level during detraining. The Medical Doctors could consider also vigorous intensity exercise on the prescription of physical exercise for elderly. :
Spinal cord injured (SCI) individuals show an altered hemodynamic response to metaboreflex activa... more Spinal cord injured (SCI) individuals show an altered hemodynamic response to metaboreflex activation due to a reduced capacity to vasoconstrict the venous and arterial vessels below the level of the lesion. Exercise training was found to enhance circulating catecholamines and to improve cardiac preload and venous tone in response to exercise in SCI subjects. Therefore, training would result in enhanced diastolic function and capacity to vasoconstrict circulation. The aim of this study was to test the hypothesis that one year of training improves hemodynamic response to metaboreflex activation in these subjects. Nine SCI individuals were enrolled and underwent a metaboreflex activation test at the beginning of the study (T0) and after one year of training (T1). Hemodynamics were assessed by impedance cardiography and echocardiography at both T0 and T1. Results show that there was an increment in cardiac output response due to metaboreflex activity at T1 as compared to T0 (545.4 ± 68...
While VO 2max has been widely investigated, there is few research on anaerobic capacity (AC) in s... more While VO 2max has been widely investigated, there is few research on anaerobic capacity (AC) in soccer players. Previous studies reported that AC is age-dependent and that young individuals had lower AC compared with adults. Thus, we wondered whether AC would have proven more useful than VO 2max in differentiating adult soccer players from young players. A total of 37 male athletes from a professional team were recruited and divided into two sub-groups: the adult (AD, n = 20) group, older than 19 years, and the young (YO, n = 17) group, ranged from 16 to 18 years. Each participant underwent an incremental test on a treadmill to assess maximal velocity (V max ), anaerobic threshold (AT) and VO 2max and a supramaximal exercise at a velocity 10 % higher than V max to measure AC. The AD group reached higher AT and VO 2max with respect to the YO group (55.23 ± 4.65 vs. 51.48 ± 4.73 mL min -1 kg -1 ), whereas no difference was found in parameters related to the AC. In conclusion, young soccer players had the same AC as adult, but they displayed a lower VO 2max . These findings indicated that AC in professional players is fully developed already when they are young while aerobic capacity is still to be developed.
The beneficial effects of beetroot juice supplementation (BJS) have been tested during cycling, w... more The beneficial effects of beetroot juice supplementation (BJS) have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO₂), carbon dioxide production (VCO₂), pulmonary ventilation (VE), and aerobic energy cost (AEC) of swimming were measured. One was a control swimming test (CSW) and the other a swimming test after six days of BJS (0.5 l/day organic beetroot juice containing about 5.5 mmol of NO₃⁻). Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively). Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg⁻¹1·h⁻¹ during the BJS test). The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold.
This study aimed at comparing maximal oxygen uptake (VO 2max ), maximal heart rate (HR max ), and... more This study aimed at comparing maximal oxygen uptake (VO 2max ), maximal heart rate (HR max ), and anaerobic threshold (AT) obtained from tethered swimming (SW) and three other testing procedures: cycling (CY), running (RU), and arm cranking (AC). Variables were assessed in 12 trained male swimmers by a portable gas analyzer connected to a modified snorkel system to allow expired gases collection during swimming. Athletes exhibited a higher VO 2max during the SW test as compared to the CY and the AC tests. There was no significant difference in VO 2max between the SW and the RU test, but the Bland and Altman plot highlighted a poor agreement between results. Moreover, AT occurred at higher workloads during SW in comparison to the other tests. These results do not support the use of any unspecific testing procedures to estimate VO 2max , HR max , and AT for swimming.
Crisafulli A, Tocco F, Milia R, Angius L, Pinna M, Olla S, Roberto S, Marongiu E, Porcu M, Concu ... more Crisafulli A, Tocco F, Milia R, Angius L, Pinna M, Olla S, Roberto S, Marongiu E, Porcu M, Concu A. Progressive improvement in hemodynamic response to muscle metaboreflex in heart transplant recipients. Exercise capacity remains lower in heart transplant recipients (HTRs) following transplant compared with normal subjects, despite improved cardiac function. Moreover, metaboreceptor activity in the muscle has been reported to increase. The aim of the present investigation was to assess exercise capacity together with metaboreflex activity in HTR patients for 1 yr following heart transplant, to test the hypothesis that recovery in exercise capacity was paralleled by improvements in response to metaboreflex. A cardiopulmonary test for exercise capacity and V O2max and hemodynamic response to metaboreflex activation obtained by postexercise ischemia were gathered in six HTRs and nine healthy controls (CTL) four times: at the beginning of the study (T0, 42 Ϯ 6 days after transplant), at the 3rd, 6th, and 12th month after TO (T1, T2, and T3). The main results were: 1) exercise capacity and V O2max were seen to progressively increase in HTRs; 2) at T0 and T1, HTRs achieved a higher blood pressure response in response to metaboreflex compared with CTL, and this difference disappeared at T2 and T3; and 3) this exaggerated blood pressure response was the result of a systemic vascular resistance increment. This study demonstrates that exercise capacity progressively improves in HTRs after transplant and that this phenomenon is accompanied by a progressive reduction of the metaboreflex-induced increase in blood pressure and systemic vascular resistance. These facts indicate that, despite improved cardiac function, resetting of cardiovascular regulation in HTRs requires months.
Applied Physiology, Nutrition, and Metabolism, 2014
Fencing is an Olympic sport in which athletes fight one against one using bladed weapons. Contest... more Fencing is an Olympic sport in which athletes fight one against one using bladed weapons. Contests consist of three 3-min bouts, with rest intervals of 1 min between them. No studies investigating oxygen uptake and energetic demand during fencing competitions exist, thus energetic expenditure and demand in this sport remain speculative. The aim of this study was to understand the physiological capacities underlying fencing performance. Aerobic energy expenditure and the recruitment of lactic anaerobic metabolism were determined in 15 athletes (2 females and 13 males) during a simulation of fencing by using a portable gas analyzer (MedGraphics VO2000), which was able to provide data on oxygen uptake, carbon dioxide production and heart rate. Blood lactate was assessed by means of a portable lactate analyzer. Average group energetic expenditure during the simulation was (mean ± SD) 10.24 ± 0.65 kcal·min −1 , corresponding to 8.6 ± 0.54 METs. Oxygen uptakeand heart rate were always below the level of anaerobic threshold previously assessed during the preliminary incremental test, while blood lactate reached its maximum value of 6.9 ± 2.1 mmol·L −1 during the final recovery minute between rounds. Present data suggest that physical demand in fencing is moderate for skilled fencers and that both aerobic energy metabolism and anaerobic lactic energy sources are moderately recruited. This should be considered by coaches when preparing training programs for athletes.
Marongiu E, Piepoli M, Milia R, Angius L, Pinna M, Bassareo P, Roberto S, Tocco F, Concu A, Crisa... more Marongiu E, Piepoli M, Milia R, Angius L, Pinna M, Bassareo P, Roberto S, Tocco F, Concu A, Crisafulli A. Effects of acute vasodilation on the hemodynamic response to muscle metaboreflex. The aim of the present study was to test the contribution of stroke volume (SV) in hemodynamic response to muscle metaboreflex activation in healthy individuals. We hypothesized that an acute decrease in cardiac afterload and preload due to the administration of a vasodilating agent could reduce postexercise muscle ischemia (PEMI)-induced SV response. Ten healthy males (age 33.6 Ϯ 1.3 yr) were enrolled and randomly assigned to the following study protocol: 1) PEMI session, 2) control exercise recovery (CER) session, 3) PEMI after sublingual administration of 5 mg of isosorbide dinitrate (ISDN), and 4) CER after ISDN. Central hemodynamics were evaluated by means of impedance cardiography. The main findings were a blunted SV response during metaboreflex following acute arterial and venous vasodilation, associated with a reduction in cardiac diastolic time and filling, and a decrement of systemic vascular resistance. These hemodynamic changes restrain blood pressure response during metaboreflex activation. Our results indicate that hemodynamic response to metaboreflex activation is a highly integrated phenomenon encompassing complex interplay between heart rate, cardiac performance, preload, and afterload and that impairment of one or more of these parameters leads to altered hemodynamic response to metaboreflex.
Roberto S, Marongiu E, Pinna M, Angius L, Olla S, Bassareo P, Tocco F, Concu A, Milia R, Crisaful... more Roberto S, Marongiu E, Pinna M, Angius L, Olla S, Bassareo P, Tocco F, Concu A, Milia R, Crisafulli A. Altered hemodynamics during muscle metaboreflex in young type 1 diabetes patients.
Clinical Practice & Epidemiology in Mental Health, 2015
Motor commands to perform exercise tasks may also induce activation of cardiovascular centres to ... more Motor commands to perform exercise tasks may also induce activation of cardiovascular centres to supply the energy needs of the contracting muscles. Mental stressors per se may also influence cardiovascular homeostasis. We investigated the cardiovascular response of trained runners simultaneously engaged in mental and physical tasks to establish if aerobically trained subjects could develop, differently from untrained ones, nervous facilitation in the brain cardiovascular centre. Methods : Cardiovascular responses of 8 male middle-distance runners (MDR), simultaneously engaged in mental (colour-word interference test) and physical (cycle ergometer exercise) tasks, were compared with those of 8 untrained subjects. Heart rate, cardiac (CI) and stroke indexes were assessed by impedance cardiography while arterial blood pressures were assessed with a brachial sphygmomanometer. Results : Only in MDR simultaneous engagement in mental and physical tasks induced a significant CI increase which was higher (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.05) than that obtained on summing CI values from each task separately performed. Conclusion : Aerobic training, when performed together with a mental effort, induced a CI oversupply which allowed a redundant oxygen delivery to satisfy a sudden fuel demand from exercising muscles by utilizing aerobic sources of ATP, thus shifting the anaerobic threshold towards a higher work load. From data of this study it may also be indirectly stated that, in patients with major depressive disorder, the promotion of regular low-intensity exercise together with mental engagement could ameliorate the perceived physical quality of life, thus reducing their heart risk associated with physical stress.
American Journal of Physiology - Heart and Circulatory Physiology, 2015
Patients suffering from obesity and metabolic syndrome (OMS) manifest a dysregulation in hemodyna... more Patients suffering from obesity and metabolic syndrome (OMS) manifest a dysregulation in hemodynamic response during exercise, with an exaggerated systemic vascular increase. However, it is not clear whether this is the consequence of metabolic syndrome per se or whether it is due to concomitant obesity. The aim of the present investigation was to discover whether OMS and noncomplicated obesity resulted in different hemodynamic responses during the metaboreflex. Twelve metabolically healthy but obese subjects (MHO; 7 women), 13 OMS patients (5 women), and 12 normal age-matched controls (CTL; 6 women) took part in this study. All participants underwent a postexercise muscle ischemia protocol to evaluate the metaboreflex activity. Central hemodynamics were evaluated by impedance cardiography. The main result shows an exaggerated increase in systemic vascular resistance from baseline during the metaboreflex in the OMS patients as compared with the other groups (481.6 ± 180.3, -0.52 ± 177.6, and -60.5 ± 58.6 dynes·s(-1)·cm(-5) for the OMS, the MHO, and the CTL groups, respectively; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). Moreover, the MHO subjects and the CTL group showed an increase in cardiac output during the metaboreflex (288.7 ± 325.8 and 703.8 ± 276.2 ml/m increase with respect to baseline), whereas this parameter tended to decrease in the OMS group (-350 ± 236.5 ml/m). However, the blood pressure response, which tended to be higher in the OMS patients, was not statistically different between groups. The results of the present investigation suggest that OMS patients have an exaggerated vasoconstriction in response to metaboreflex activation and that this fact is not due to obesity per se.
The aim of the present investigation was to assess the role of aging on the contribution of diast... more The aim of the present investigation was to assess the role of aging on the contribution of diastolic function during metaboreflex activation. In particular, it aimed to determine whether age-related impairment in diastolic function would produce a different hemodynamic response in elderly subjects (EG) as compared to young controls (CTL). Hemodynamic response to metaboreflex activation obtained by post-exercise muscle ischemia (PEMI) was gathered in 22 EG and 20 healthy CTL. Subjects also performed a control exercise recovery (CER) test to compare data from the PEMI test. The main results showed that the EG group reached higher mean arterial blood pressure (MAP) increment than the CTL group during the PEMI test (+11.2 ± 8.6 vs 6.1 ± 6.4 mmHg in the EG and CTL group, respectively). Moreover, the mechanism by which this response was achieved was different between the two groups. In detail, EG reached the target MAP by increasing systemic vascular resistance (+235.2 ± 315.1 vs -44.4 ± 167.7 dynes s(-1) cm(-5) for the EG and the CTL group, respectively), whereas MAP response in the CTL was the result of an increase in cardiac pre-load (-1.5 ± 11.2 vs 14 ± 13.7 ml in end-diastolic volume for the EG and the CTL group, respectively), which led to a rise in stroke volume and cardiac output. Moreover, early filling peak velocities showed a higher response in the CTL than EG group. This study demonstrates that diastolic function is important for normal hemodynamic adjustment during the metaboreflex and to avoid excessive vasoconstriction.
Exercise training for subjects over 65 should be applied to improve quality of life. However, phy... more Exercise training for subjects over 65 should be applied to improve quality of life. However, physiological adaptations are transitory and disappear after training reduction or cessation (Bousquet et all, 2013 - Mujika & Bousquet, 2010). Beside detraining exerts well known effects in young athletes, while limited information is available for elderly individuals. PURPOSE: The aim of this study was to investigate the effects of 8 weeks of detraining in elderly subjects (age > 65 yrs), after 12 weeks of exercise prescription at vigorous intensity. METHODS: 17 healthy participants (69.3 ± 4.3 yrs) performed a randomized controlled trial on training program about 12 weeks at vigorous intensity (range 64-85% of Heart Rate Reserve) followed by 8 weeks of detraining. Before and after the training cessation period, subjects underwent an exercise test on a cycle Ergometer test until exhaustion to assess VO2max. Heart Rate Recovery HRR, Waist-Hip ratio (WHR) and Body Mass Index (BMI) were a...
Exercise training for subjects over 65 should be applied to improve quality of life. However, phy... more Exercise training for subjects over 65 should be applied to improve quality of life. However, physiological adaptations are transitory and disappear after training reduction or cessation (Bousquet et all, 2013 -Mujika & Bousquet, 2010. Beside detraining exerts well known effects in young athletes, while limited information is available for elderly individuals. PURPOSE: The aim of this study was to investigate the effects of 8 weeks of detraining in elderly subjects (age > 65 yrs), after 12 weeks of exercise prescription at vigorous intensity. METHODS: 17 healthy participants (69.3 ± 4.3 yrs) performed a randomized controlled trial on training program about 12 weeks at vigorous intensity (range 64-85% of Heart Rate Reserve) followed by 8 weeks of detraining. Before and after the detraining period, subjects underwent an exercise test on a cycle Ergometer test until exhaustion to assess VO2max. Heart Rate Recovery HRR, Waist-Hip ratio (WHR) and Body Mass Index (BMI) were also assessed. Paired t-test were used to compare the detraining effects on all variables before and after 8 detraining weeks. RESULTS:VO2max decreased by 6,65% during the detraining period (24.2 ± 4.7 to 22.6 ± 4.5 ml/kg/min p=0.32). However, BMI decreased by 5,3% (26.5 ± 3.5 to 25.1 ± 3.9 kg/m2 p = 0.24). Conversely HRR increased by 7% (62.1 ± 8.8 to 67.1 ± 9.2 bpm p=0.15 ) these decrement were not significant. WHR increased significantly by 9% (0.92 ± 0.06 to 1.01 ± 0.09 p<0.05 ) CONCLUSIONS:In the present investigation, after the detraining period following a vigorous training program, subjects were able to maintain a level of VO2max without a negative effect. Training exercise at vigorous intensity, instead of moderate intensity which is more commonly applied, were more positive also for BMI and HRR, otherwise the WHR were significantly different. Previous studies, employing moderate intensity (<64% Heart Rate Reserve) showed high tendencies to return back to the pre-training level during detraining. The Medical Doctors could consider also vigorous intensity exercise on the prescription of physical exercise for elderly. :
Spinal cord injured (SCI) individuals show an altered hemodynamic response to metaboreflex activa... more Spinal cord injured (SCI) individuals show an altered hemodynamic response to metaboreflex activation due to a reduced capacity to vasoconstrict the venous and arterial vessels below the level of the lesion. Exercise training was found to enhance circulating catecholamines and to improve cardiac preload and venous tone in response to exercise in SCI subjects. Therefore, training would result in enhanced diastolic function and capacity to vasoconstrict circulation. The aim of this study was to test the hypothesis that one year of training improves hemodynamic response to metaboreflex activation in these subjects. Nine SCI individuals were enrolled and underwent a metaboreflex activation test at the beginning of the study (T0) and after one year of training (T1). Hemodynamics were assessed by impedance cardiography and echocardiography at both T0 and T1. Results show that there was an increment in cardiac output response due to metaboreflex activity at T1 as compared to T0 (545.4 ± 68...
While VO 2max has been widely investigated, there is few research on anaerobic capacity (AC) in s... more While VO 2max has been widely investigated, there is few research on anaerobic capacity (AC) in soccer players. Previous studies reported that AC is age-dependent and that young individuals had lower AC compared with adults. Thus, we wondered whether AC would have proven more useful than VO 2max in differentiating adult soccer players from young players. A total of 37 male athletes from a professional team were recruited and divided into two sub-groups: the adult (AD, n = 20) group, older than 19 years, and the young (YO, n = 17) group, ranged from 16 to 18 years. Each participant underwent an incremental test on a treadmill to assess maximal velocity (V max ), anaerobic threshold (AT) and VO 2max and a supramaximal exercise at a velocity 10 % higher than V max to measure AC. The AD group reached higher AT and VO 2max with respect to the YO group (55.23 ± 4.65 vs. 51.48 ± 4.73 mL min -1 kg -1 ), whereas no difference was found in parameters related to the AC. In conclusion, young soccer players had the same AC as adult, but they displayed a lower VO 2max . These findings indicated that AC in professional players is fully developed already when they are young while aerobic capacity is still to be developed.
The beneficial effects of beetroot juice supplementation (BJS) have been tested during cycling, w... more The beneficial effects of beetroot juice supplementation (BJS) have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO₂), carbon dioxide production (VCO₂), pulmonary ventilation (VE), and aerobic energy cost (AEC) of swimming were measured. One was a control swimming test (CSW) and the other a swimming test after six days of BJS (0.5 l/day organic beetroot juice containing about 5.5 mmol of NO₃⁻). Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively). Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg⁻¹1·h⁻¹ during the BJS test). The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold.
This study aimed at comparing maximal oxygen uptake (VO 2max ), maximal heart rate (HR max ), and... more This study aimed at comparing maximal oxygen uptake (VO 2max ), maximal heart rate (HR max ), and anaerobic threshold (AT) obtained from tethered swimming (SW) and three other testing procedures: cycling (CY), running (RU), and arm cranking (AC). Variables were assessed in 12 trained male swimmers by a portable gas analyzer connected to a modified snorkel system to allow expired gases collection during swimming. Athletes exhibited a higher VO 2max during the SW test as compared to the CY and the AC tests. There was no significant difference in VO 2max between the SW and the RU test, but the Bland and Altman plot highlighted a poor agreement between results. Moreover, AT occurred at higher workloads during SW in comparison to the other tests. These results do not support the use of any unspecific testing procedures to estimate VO 2max , HR max , and AT for swimming.
Crisafulli A, Tocco F, Milia R, Angius L, Pinna M, Olla S, Roberto S, Marongiu E, Porcu M, Concu ... more Crisafulli A, Tocco F, Milia R, Angius L, Pinna M, Olla S, Roberto S, Marongiu E, Porcu M, Concu A. Progressive improvement in hemodynamic response to muscle metaboreflex in heart transplant recipients. Exercise capacity remains lower in heart transplant recipients (HTRs) following transplant compared with normal subjects, despite improved cardiac function. Moreover, metaboreceptor activity in the muscle has been reported to increase. The aim of the present investigation was to assess exercise capacity together with metaboreflex activity in HTR patients for 1 yr following heart transplant, to test the hypothesis that recovery in exercise capacity was paralleled by improvements in response to metaboreflex. A cardiopulmonary test for exercise capacity and V O2max and hemodynamic response to metaboreflex activation obtained by postexercise ischemia were gathered in six HTRs and nine healthy controls (CTL) four times: at the beginning of the study (T0, 42 Ϯ 6 days after transplant), at the 3rd, 6th, and 12th month after TO (T1, T2, and T3). The main results were: 1) exercise capacity and V O2max were seen to progressively increase in HTRs; 2) at T0 and T1, HTRs achieved a higher blood pressure response in response to metaboreflex compared with CTL, and this difference disappeared at T2 and T3; and 3) this exaggerated blood pressure response was the result of a systemic vascular resistance increment. This study demonstrates that exercise capacity progressively improves in HTRs after transplant and that this phenomenon is accompanied by a progressive reduction of the metaboreflex-induced increase in blood pressure and systemic vascular resistance. These facts indicate that, despite improved cardiac function, resetting of cardiovascular regulation in HTRs requires months.
Applied Physiology, Nutrition, and Metabolism, 2014
Fencing is an Olympic sport in which athletes fight one against one using bladed weapons. Contest... more Fencing is an Olympic sport in which athletes fight one against one using bladed weapons. Contests consist of three 3-min bouts, with rest intervals of 1 min between them. No studies investigating oxygen uptake and energetic demand during fencing competitions exist, thus energetic expenditure and demand in this sport remain speculative. The aim of this study was to understand the physiological capacities underlying fencing performance. Aerobic energy expenditure and the recruitment of lactic anaerobic metabolism were determined in 15 athletes (2 females and 13 males) during a simulation of fencing by using a portable gas analyzer (MedGraphics VO2000), which was able to provide data on oxygen uptake, carbon dioxide production and heart rate. Blood lactate was assessed by means of a portable lactate analyzer. Average group energetic expenditure during the simulation was (mean ± SD) 10.24 ± 0.65 kcal·min −1 , corresponding to 8.6 ± 0.54 METs. Oxygen uptakeand heart rate were always below the level of anaerobic threshold previously assessed during the preliminary incremental test, while blood lactate reached its maximum value of 6.9 ± 2.1 mmol·L −1 during the final recovery minute between rounds. Present data suggest that physical demand in fencing is moderate for skilled fencers and that both aerobic energy metabolism and anaerobic lactic energy sources are moderately recruited. This should be considered by coaches when preparing training programs for athletes.
Marongiu E, Piepoli M, Milia R, Angius L, Pinna M, Bassareo P, Roberto S, Tocco F, Concu A, Crisa... more Marongiu E, Piepoli M, Milia R, Angius L, Pinna M, Bassareo P, Roberto S, Tocco F, Concu A, Crisafulli A. Effects of acute vasodilation on the hemodynamic response to muscle metaboreflex. The aim of the present study was to test the contribution of stroke volume (SV) in hemodynamic response to muscle metaboreflex activation in healthy individuals. We hypothesized that an acute decrease in cardiac afterload and preload due to the administration of a vasodilating agent could reduce postexercise muscle ischemia (PEMI)-induced SV response. Ten healthy males (age 33.6 Ϯ 1.3 yr) were enrolled and randomly assigned to the following study protocol: 1) PEMI session, 2) control exercise recovery (CER) session, 3) PEMI after sublingual administration of 5 mg of isosorbide dinitrate (ISDN), and 4) CER after ISDN. Central hemodynamics were evaluated by means of impedance cardiography. The main findings were a blunted SV response during metaboreflex following acute arterial and venous vasodilation, associated with a reduction in cardiac diastolic time and filling, and a decrement of systemic vascular resistance. These hemodynamic changes restrain blood pressure response during metaboreflex activation. Our results indicate that hemodynamic response to metaboreflex activation is a highly integrated phenomenon encompassing complex interplay between heart rate, cardiac performance, preload, and afterload and that impairment of one or more of these parameters leads to altered hemodynamic response to metaboreflex.
Roberto S, Marongiu E, Pinna M, Angius L, Olla S, Bassareo P, Tocco F, Concu A, Milia R, Crisaful... more Roberto S, Marongiu E, Pinna M, Angius L, Olla S, Bassareo P, Tocco F, Concu A, Milia R, Crisafulli A. Altered hemodynamics during muscle metaboreflex in young type 1 diabetes patients.
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