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1.
Biology (Basel) ; 12(3)2023 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-36979132

RESUMEN

Kettlebell sport (KBs) is increasingly popular, but very few studies have been focused on this discipline. This research aims to investigate the effects of KBs on body composition, strength symmetry, and segmental body composition symmetry in a sample of Italian elite athletes. Data were collected from a sample of 16 athletes of both sexes (11 men and 5 women; 34.5 ± 9.0 years of age). Anthropometric (height, weight, arm, thigh, calf, and waist circumferences), hand grip strength, and total and segmental bioelectrical variables were taken. Body composition was analysed by using specific bioelectrical impedance vector analysis (BIVA). Paired t-tests and confidence ellipses were applied to analyse bilateral differences. Elite athletes of both sexes showed high values of phase angle, indicative of high body cell mass and quality and proxy of muscle mass. Hand grip strength and body composition were symmetrical, with the only exception of a higher %FM in the right leg (Zsp: t = 3.556; p = 0.003). In conclusion, this study suggests that KBs contributes to muscle mass improvement, body composition, and strength symmetry, especially in the upper body.

2.
Front Psychol ; 13: 906336, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35712141

RESUMEN

Hypoxia can impair cognitive performance, whereas exercise can enhance it. The effects of hypoxia on cognitive performance during exercise appear to be moderated by exercise duration and intensity and by severity and duration of hypoxia and cognitive task. In normal individuals, exercise under hypoxia can evoke adverse post-exercise mood states, such as tension and fatigue. However, little is known about the effects of hypoxia during exercise in trained athletes. The purpose of this study was to investigate how hypoxia affected executive functions and mood states, assessed, respectively, during and post-exercise and to explore the role of motivation moderators, such as inhibition and activation systems (BIS-BAS). Two different sessions of exercise in normoxia and hypoxia (FiO2 13%), each lasting 18 min, were randomly assigned in a counterbalanced order and administered to seventeen male athletes. During exercise bouts, participants performed a mental task (BST) aimed to produce cognitive interference and suppression. Reaction times and accuracy of responses were recorded. After 5 min, all participants completed two questionnaires assessing mood states (ITAMS) and incidence of symptoms potentially related to hypoxia (AMS-C). The results show that hypoxia impairs cognitive performance in terms of slower reaction times, but a high BAS attenuates this effect. Participants with high BAS show an equivalent cognitive performance under hypoxia and normoxia conditions. No effects were found on mood states. Further research is required to investigate the role of BAS, cognitive abilities, and mood states in prolonged hypoxic conditions.

3.
J Sports Med Phys Fitness ; 61(9): 1309-1313, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33269886

RESUMEN

Vinson and Ama Dablam are summits of different altitudes (4897 and 6812 m respectively). There are no published studies comparing physiological adaptations occurring after climbing both peaks yet. This case study compares changes in certain physiological parameters and body composition of a mountaineer who ascended both peaks. The athlete was a mountaineer who already climbed the 7 Summits©. Baseline body composition, physical capacity, and cerebral oxygenation during effort were measured before and after his departure. Body composition was estimated by electrical bio-impedance, while physical capacity was measured with an incremental exercise test (treadmill) conducted in normoxia and in hypoxia corresponding to about 4000 m. Hypoxia was obtained with a hypoxic gas generator. During tests, cerebral oxygenation was estimated with near infrared spectroscopy. The ascent of mount Vinson and Ama Dablam took 4 and 15 days respectively. The ascent of mount Vinson resulted in a 2.0 kg drop in body mass and a reduction in body fat (from 15.5% to 12.1%). The ascent of Ama Dablam reduced body mass by 3.7 kg, with an increase in body fat from 11.9% to 14.7%. Physical capacity was almost unchanged after both expeditions, although there was a reduction in maximum heart rate in relation to workload after Ama Dablam. Finally, after Ama Dablam there was an increase in cerebral oxygenation during effort both in normoxia and hypoxia. It was concluded that the longer duration and the higher altitude during the Ama Dablam expedition resulted in more evident physiological changes.


Asunto(s)
Altitud , Expediciones , Adaptación Fisiológica , Humanos , Hipoxia , Estado Nutricional
4.
Artículo en Inglés | MEDLINE | ID: mdl-32075041

RESUMEN

The aim of the study was to analyze total and regional body composition in Tai Chi Chuan (TCC) middle-aged and elderly practitioners. A cross-sectional study on 139 Italian subjects was realized: 34 TCC practitioners (14 men, 20 women; 62.8 ± 7.4 years) and 105 sedentary volunteers (49 men, 56 women; 62.8 ± 6.4 years). Anthropometric measurements (height, weight, arm, waist, and calf circumferences), hand-grip strength, and physical capacity values were collected. Total and regional (arm, leg, and trunk) body composition was analyzed by means of specific bioelectrical impedance vector analysis (specific BIVA). TCC practitioners of both sexes were characterized by a normal nutritional status, normal levels of physical capacity, and normal values of hand-grip strength. Compared to controls, they showed lower percentages of fat mass (lower specific resistance) in the total body, the arm, and the trunk, and higher muscle mass (higher phase angle) in the trunk, but lower muscle mass in the arm. Sexual dimorphism was characterized by higher muscle mass (total body, arm, and trunk) and lower %FM (arm) in men; sex differences were less accentuated among TCC practitioners than in the control. TCC middle-aged and elderly practitioners appear to be less affected by the process of physiological aging and the associated fat mass changes, compared to sedentary people.


Asunto(s)
Taichi Chuan , Tejido Adiposo , Adulto , Anciano , Envejecimiento , Composición Corporal , Índice de Masa Corporal , Estudios Transversales , Impedancia Eléctrica , Femenino , Fuerza de la Mano , Humanos , Masculino , Persona de Mediana Edad
5.
Front Psychol ; 11: 611558, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33424722

RESUMEN

Previous research has documented that type 2 diabetes mellitus (T2DM) is associated with cognitive impairment. Psychological variables were repeatedly investigated to understand why T2DM patients are poorly active, despite standards of medical care recommends performing aerobic and resistance exercise regularly and reducing the amount of time spent sitting. This exploratory study aims to investigate how affective variables as thoughts, feelings, and individuals' stage of exercise adoption can modulate low cognitive performances during an experimental procedure based on exercise. The Exercise Thoughts Questionnaire (ETQ), Exercise-Induced Feeling Scale (EFI), and Physical Activity Stage of Change were administered to a sample of 12 T2DM patients. The Bivalent Shape Task (BST) alone (BST), BST with exercise [control exercise recovery (CER) + BST], and BST with metaboreflex [post-exercise muscle ischemia (PEMI) + BST] were used as mental task, and response time to congruent, incongruent, and neutral stimuli was recorded. Concomitant cerebral oxygenation (COX) was evaluated by near-infrared spectroscopy (NIRS). As expected, T2DM patients performed significantly better when the stimulus was presented in congruent trials (followed by neutral and incongruent). In the CER + BST session, T2DM patients showed longer reaction time to incongruent trials than in the PEMI + BST and BST alone sessions. Positive feelings toward exercise seem to modulate cognitive performances in high challenging task only if T2DM patients were conscious to play exercise. These results could provide some insights for health intervention targeting exercise for patients with T2DM in order to enhance cognitive performances.

6.
Front Psychol ; 10: 1845, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31440195

RESUMEN

The metabolic syndrome (MS) has been associated with poor performances in multiple cognitive domains, as processing speed, visuo-spatial abilities, and executive functioning. Exercise is a critical factor for MS people's vulnerability to cognitive dysfunction, because this may be beneficial to reduce cognitive impairment, but limited physical activity and impaired cerebral blood flow in response to exercise have been reported by individuals suffering from MS. Using an attentional interference test, the Bivalent Shape Task (BST), and metaboreflex, we analyzed cognitive performance and cerebral oxygenation (COX) in 13 MS people (five women), and 14 normal age-matched control (CTL, six women). Five different sessions were administered to all participants, each lasting 12 min: control exercise recovery (CER), post-exercise muscle ischemia (PEMI) to activate the metaboreflex, CER + BST, PEMI + BST, and BST alone. During each session, cognitive performance was assessed by means of response times and response accuracy with which participants make the decision and COX was evaluated by near infrared spectroscopy with sensors applied in the forehead. Compared to CTL, MS group performed significantly worse in all sessions (F = 4.18; p = 0.05; ES = 0.13): their poorest performance was observed in the BST alone session. Moreover, when BST was added to PEMI, individuals of the CTL group significantly increased their COX compared to baseline (103.46 ± 3.14%), whereas this capacity was impaired in MS people (102.37 ± 2.46%). It was concluded that: (1) MS affects cognitive performance; (2) people with MS were able to enhance COX during exercise, but they impair their COX when an attentional interference task was added.

7.
Eur J Appl Physiol ; 119(5): 1137-1148, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30783735

RESUMEN

PURPOSE: Little is known about the cardiovascular effects of the transition from exercise in hypoxia (EH) to normoxia. This investigation aimed to assess hemodynamics during the metaboreflex elicited in normoxia after EH. METHODS: Ten trained athletes (four females and six males, age 35.6 ± 8.4 years) completed a cardiopulmonary test to determine the workload at anaerobic threshold (AT). On separate days, participants performed three randomly assigned exercise sessions (10 min pedalling at 80% of AT): (1) one in normoxia (EN); (2) one in normobaric hypoxia with FiO2 15.5% (EH15.5%); and (3) one in normobaric hypoxia with FiO2 13.5% (EH13.5%). After each session, the following protocol was randomly assigned: either (1) post-exercise muscle ischemia after cycling for 3 min, to study the metaboreflex, or (2) a control exercise recovery (CER) session, without any metaboreflex stimulation. RESULTS: The main result were that both EH15.5% and EH13.5% impaired (p < 0.05) the ventricular filling rate response during the metaboreflex (- 18 ± 32 and - 20 ± 27 ml s-1), when compared to EN (+ 29 ± 32 ml s-1), thereby causing a reduction in stroke volume response (- 9.1 ± 3.2, - 10.6 ± 8.7, and + 5 ± 5.7 ml for EH15.5%, EH13.5% and EN test, respectively, p < 0.05). Moreover, systemic vascular resistance was increased after the EH15.5% and the EH13.5% in comparison with the EN test. CONCLUSIONS: These data demonstrate that moderate exercise in hypoxia impairs the capacity to enhance venous return during the metaboreflex stimulated in normoxia. Overall, there is a functional shift from a flow to vasoconstriction-mediated mechanism for maintaining the target blood pressure during the metaboreflex.


Asunto(s)
Umbral Anaerobio , Hemodinámica , Hipoxia/fisiopatología , Músculo Esquelético/fisiología , Acondicionamiento Físico Humano/métodos , Reflejo , Adulto , Femenino , Humanos , Masculino , Acondicionamiento Físico Humano/efectos adversos , Distribución Aleatoria
8.
J Appl Physiol (1985) ; 126(2): 444-453, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30543497

RESUMEN

Metaboreflex is a reflex triggered during exercise or postexercise muscle ischemia (PEMI) by metaboreceptor stimulation. Typical features of metaboreflex are increased cardiac output (CO) and blood pressure. Patients suffering from metabolic syndrome display hemodynamic abnormalities, with an exaggerated systemic vascular resistance (SVR) and reduced CO response during PEMI-induced metaboreflex. Whether patients with type 2 diabetes mellitus (DM2) have similar hemodynamic abnormalities is unknown. Here we contrast the hemodynamic response to PEMI in 14 patients suffering from DM2 (age 62.7 ± 8.3 yr) and in 15 age-matched controls (CTLs). All participants underwent a control exercise recovery reference test and a PEMI test to obtain the metaboreflex response. Central hemodynamics were evaluated by unbiased operator-independent impedance cardiography. Although the blood pressure response to PEMI was not significantly different between the groups, we found that the SVR and CO responses were reversed in patients with DM2 as compared with the CTLs (SVR: 392.5 ± 549.6 and -14.8 ± 258.9 dyn·s-1·cm-5; CO: -0.25 ± 0.63 and 0.46 ± 0.50 l/m, respectively, in DM2 and in CTL groups, respectively; P < 0.05 for both). Of note, stroke volume (SV) increased during PEMI in the CTL group only. Failure to increase SV and CO was the consequence of reduced venous return, impaired cardiac performance, and augmented afterload in patients with DM2. We conclude that patients with DM2 have an exaggerated vasoconstriction in response to metaboreflex activation not accompanied by a concomitant increase in heart performance. Therefore, in these patients, blood pressure response to the metaboreflex relies more on SVR increases rather than on increases in SV and CO. NEW & NOTEWORTHY The main new finding of the present investigation is that subjects with type 2 diabetes mellitus have an exaggerated vasoconstriction in response to metaboreflex activation. In these patients, blood pressure response to the metaboreflex relies more on systemic vascular resistance than on cardiac output increments.


Asunto(s)
Células Quimiorreceptoras/metabolismo , Diabetes Mellitus Tipo 2/fisiopatología , Metabolismo Energético , Hemodinámica , Contracción Muscular , Músculo Esquelético/inervación , Reflejo , Anciano , Presión Sanguínea , Gasto Cardíaco , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Factores de Tiempo , Vasoconstricción
9.
Front Physiol ; 9: 1736, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30618781

RESUMEN

Objective: Blood flow restriction training (BFRT) has been proposed to induce muscle hypertrophy, but its safety remains controversial as it may increase mean arterial pressure (MAP) due to muscle metaboreflex activation. However, BFR training also causes metabolite accumulation that may desensitize type III and IV nerve endings, which trigger muscle metaboreflex. Then, we hypothesized that a period of BFR training would result in blunted hemodynamic activation during muscle metaboreflex. Methods: 17 young healthy males aged 18-25 yrs enrolled in this study. Hemodynamic responses during muscle metaboreflex were assessed by means of postexercise muscle ischemia (PEMI) at baseline (T0) and after 1 month (T1) of dynamic BFRT. BFRT consisted of 3-min rhythmic handgrip exercise applied 3 days/week (30 contractions per minute at 30% of maximum voluntary contraction) in the dominant arm. On the first week, the occlusion was set at 75% of resting systolic blood pressure (always obtained after 3 min of resting) and increased 25% every week, until reaching 150% of resting systolic pressure at week four. Hemodynamic measurements were assessed by means of impedance cardiography. Results: BFRT reduced MAP during handgrip exercise (T1: 96.3 ± 8.3 mmHg vs. T0: 102.0 ± 9.53 mmHg, p = 0.012). However, no significant time effect was detected for MAP during the metaboreflex activation (P > 0.05). Additionally, none of the observed hemodynamic outcomes, including systemic vascular resistance (SVR), showed significant difference between T0 and T1 during the metaboreflex activation (P > 0.05). Conclusion: BFRT reduced blood pressure during handgrip exercise, thereby suggesting a potential hypotensive effect of this modality of training. However, MAP reduction during handgrip seemed not to be provoked by lowered metaboreflex activity.

10.
Am J Physiol Heart Circ Physiol ; 314(3): H452-H463, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29127237

RESUMEN

This study was devised to investigate the effect of coronary artery disease (CAD) without overt signs of heart failure on the cardiovascular responses to muscle metaboreflex activation. We hypothesized that any CAD-induced preclinical systolic and/or diastolic dysfunction could impair hemodynamic response to the metaboreflex test. Twelve men diagnosed with CAD without any sign or symptoms of heart failure and 11 age-matched healthy control (CTL) subjects participated in the study. Subjects performed a postexercise muscle ischemia (PEMI) test to activate the metaboreflex. They also performed a control exercise recovery test to compare data from the PEMI test. The main results were that the CAD group reached a similar mean arterial blood pressure response as the CTL group during PEMI. However, the mechanism by which this response was achieved was different between groups. In particular, CAD achieved the target mean arterial blood pressure by increasing systemic vascular resistance (+383.8 ± 256.6 vs. +91.2 ± 293.5 dyn·s-1·cm-5 for the CAD and CTL groups, respectively), the CTL group by increasing cardiac preload (-0.92 ± 8.53 vs. 5.34 ± 4.29 ml in end-diastolic volume for the CAD and CTL groups, respectively), which led to an enhanced stroke volume and cardiac output. Furthermore, the ventricular filling rate response was higher in the CTL group than in the CAD group during PEMI ( P < 0.05 for all comparisons). This study confirms that diastolic function is pivotal for normal hemodynamics during the metaboreflex. Moreover, it provides evidence that early signs of diastolic impairment attributable to CAD can be detected by the metaboreflex test. NEW & NOTEWORTHY Individuals suffering from coronary artery disease without overt signs of heart failure may show early signs of diastolic dysfunction, which can be detected by the metaboreflex test. During the metaboreflex, these subjects show impaired preload and stroke volume responses and exaggerated vasoconstriction compared with controls.


Asunto(s)
Células Quimiorreceptoras/metabolismo , Enfermedad de la Arteria Coronaria/fisiopatología , Metabolismo Energético , Corazón/inervación , Hemodinámica , Contracción Muscular , Músculo Esquelético/inervación , Reflejo , Adaptación Fisiológica , Anciano , Presión Arterial , Gasto Cardíaco , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/metabolismo , Progresión de la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Resistencia Vascular , Vasoconstricción , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/fisiopatología , Función Ventricular Izquierda
11.
Int J Sport Nutr Exerc Metab ; 28(5): 558-563, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29252058

RESUMEN

During solitary sailing, the sailor is exposed to sleep deprivation and difficulties in consuming regular meals. Sailor weight loss is often reported. In the present case study, we describe changes in the physical capacity and nutritional status of an athlete attempting a single-handed yacht race around the globe. An Italian male ocean racer (Gaetano Mura) asked for our help to reach an optimum level of physical and nutritional preparation. We planned his diet after assessing his anthropometric parameters and body composition, as well as his usual energy intake and nutritional expenditure. The diet consisted of 120 meals stored in sealed plastic bags. Before his departure, GM performed two incremental exercise tests (cycle ergometry and arm crank ergometry) to assess his physical capacity. Cardiac functions were also estimated by Doppler echocardiography. All measures and exercise tests were repeated 10 days after GM finished the race, which lasted 64 days. Anthropometric measures did not change significantly, with the exception of arm fat area and thigh muscle area, which decreased. There were evident increments in maximum oxygen intake and maximum workload during arm cranking after the race. On the contrary, maximum oxygen uptake and maximum workload decreased during cycling. Finally, end-diastolic and stroke volume decreased after the race. It was concluded that nutritional counseling was useful to avoid excessive changes in nutritional status and body composition due to 64 days of solitary navigation. However, a reduction in physical leg capacity and cardiovascular functions secondary to leg disuse were present.


Asunto(s)
Composición Corporal , Dieta , Estado Nutricional , Deportes Acuáticos/fisiología , Antropometría , Conducta Competitiva , Dietética , Ingestión de Energía , Metabolismo Energético , Humanos , Masculino , Persona de Mediana Edad , Navíos , Pérdida de Peso
12.
Front Physiol ; 7: 531, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27895592

RESUMEN

Patients with multiple sclerosis (MS) have an increased systemic vascular resistance (SVR) response during the metaboreflex. It has been hypothesized that this is the consequence of a sedentary lifestyle secondary to MS. The purpose of this study was to discover whether a 6-month training program could reverse this hemodynamic dysregulation. Patients were randomly assigned to one of the following two groups: the intervention group (MSIT, n = 11), who followed an adapted training program; and the control group (MSCTL, n = 10), who continued with their sedentary lifestyle. Cardiovascular response during the metaboreflex was evaluated using the post-exercise muscle ischemia (PEMI) method and during a control exercise recovery (CER) test. The difference in hemodynamic variables such as stroke volume (SV), cardiac output (CO), and SVR between the PEMI and the CER tests was calculated to assess the metaboreflex response. Moreover, physical capacity was measured during a cardiopulmonary test till exhaustion. All tests were repeated after 3 and 6 months (T3 and T6, respectively) from the beginning of the study. The main result was that the MSIT group substantially improved parameters related to physical capacity (+5.31 ± 5.12 ml·min-1/kg in maximal oxygen uptake at T6) in comparison with the MSCTL group (-0.97 ± 4.89 ml·min-1/kg at T6; group effect: p = 0.0004). However, none of the hemodynamic variables changed in response to the metaboreflex activation. It was concluded that a 6-month period of adapted physical training was unable to reverse the hemodynamic dys-regulation in response to metaboreflex activation in these patients.

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