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1.
Blood Cells Mol Dis ; 107: 102853, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38574498

RESUMO

Sickle cell disease (SCD) is an hemoglobinopathy resulting in the production of an abnormal Hb (HbS) which can polymerize in deoxygenated conditions, leading to the sickling of red blood cells (RBC). These alterations can decrease the oxygen-carrying capacity leading to impaired function and energetics of skeletal muscle. Any strategy which could reverse the corresponding defects could be of interest. In SCD, endurance training is known to improve multiples muscle properties which restores patient's exercise capacity but present reduced effects in anemic patients. Hydroxyurea (HU) can increase fetal hemoglobin production which can reduce anemia in patients. The present study was conducted to determine whether HU can improve the effects of endurance training to improve muscle function and energetics. Twenty SCD Townes mice have been trained for 8 weeks with (n = 11) or without (n = 9) HU. SCD mice muscle function and energetics were analyzed during a standardized rest-exercise-recovery protocol, using Phosphorus-31 Magnetic resonance spectroscopy (31P-MRS) and transcutaneous stimulation. The combination of training and HU specifically decreased fatigue index and PCr consumption while muscle oxidative capacity was improved. These results illustrate the potential synergistic effects of endurance training and HU on muscle function and energetics in sickle cell disease.

2.
BMC Pulm Med ; 24(1): 196, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649893

RESUMO

BACKGROUND: Comparisons between endurance training (ET) and resistance training (RT) have produced equivocal findings in chronic obstructive pulmonary disease (COPD) patients. The purpose of our study is to investigate the effectiveness and long-term outcomes of adding ET and RT to conventional medical treatment in patients with COPD. A secondary objective is to investigate the clinical improvements resulting from exercise training in patients with different disease severities. METHODS: The study was a multicenter, prospective trial in people with stable COPD. The cohort was randomized to three groups: individualized medical treatment group (MT), MT + endurance training group (MT + ET) and MT + resistance training group (MT + RT). Exercise was performed 3 times weekly over a 12-week period. The endpoints of exercise capacity, health-related quality of life, COPD symptoms, lung function, and anxiety and depression questionnaires were re-evaluated at baseline, at the completion of the intervention and at 6 and 12-month follow-up. According to the COPD assessment tool offered by GOLD guidelines, patients were stratified into GOLD A and B groups and GOLD C and D groups for further subgroup analysis. RESULTS: The intention-to-treat (ITT) population included 366 patients, 328 of them completed the study protocol over 12 months (the PP-population). There were no significant differences in the primary outcome, quality of life, between patients who underwent medical treatment (MT) alone, MT + endurance training (MT + ET), or MT + resistance training (MT + RT) at the completion of the intervention, 6-, or 12-month follow-up. Additionally, no significant differences were observed between MT, MT + RT, or MT + ET groups concerning the primary outcome, exercise capacity (3MWD), after initial 3 months of intervention. However, a small statistically significant difference was noted in favor of MT + ET compared to MT + RT at 12 months (ITT: Δ3MWD in ET vs RT = 5.53 m, 95% confidence interval: 0.87 to 13.84 m, P = 0.03) (PP: Δ3MWD in ET vs RT = 7.67 m, 95% confidence interval: 0.93 to 16.27 m, P = 0.04). For patients in the GOLD C and D groups, improvement in quality of life following ET or RT was significantly superior to medical intervention alone. Furthermore, upon completion of the exercise regimen, RT exhibited a greater improvement in anxiety compared to ET in these patients (ITT: ΔHAD-A at 3-month: RT = -1.63 ± 0.31 vs ET = -0.61 ± 0.33, p < 0.01) (PP: ΔHAD-A at 3-month: RT = -1.80 ± 0.36 vs ET = -0.75 ± 0.37, p < 0.01). CONCLUSIONS: Our study presents evidence of the beneficial effects of ET and RT in combination with standard medical treatment, as well as the long-term effects over time after the intervention. While the statistically significant effect favoring ET over RT in terms of exercise capacity was observed, it should be interpreted cautiously. Patients in severe stages of COPD may derive greater benefits from either ET or RT and should be encouraged accordingly. These findings have implications for exercise prescription in patients with COPD. TRIAL REGISTRATION: ChiCTR-INR-16009892 (17, Nov, 2016).


Assuntos
Treino Aeróbico , Tolerância ao Exercício , Doença Pulmonar Obstrutiva Crônica , Qualidade de Vida , Treinamento de Força , Humanos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/terapia , Doença Pulmonar Obstrutiva Crônica/reabilitação , Treinamento de Força/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Treino Aeróbico/métodos , Estudos Prospectivos , Resultado do Tratamento , Volume Expiratório Forçado , Ansiedade , Depressão , Terapia Combinada
3.
Artigo em Inglês | MEDLINE | ID: mdl-38502204

RESUMO

The primary aim of this study was to investigate the impact of aerobic endurance training in schizophrenic inpatients on cognitive performance in a clinical routine setting. Of secondary interest was the influence on psychopathological symptoms. A total of 31 schizophrenic inpatients were randomly assigned to receive either controlled endurance training or occupational therapy. The experimental group underwent endurance training of 20-30 min each, 3 times per week for a total of up to 22 training sessions. The control group received about 90 min of occupational therapy, 2-3 times per week for up to 22 sessions. Cognitive performance was assessed via an extensive neuropsychological examination before randomization and prior to discharge. Significant improvements in cognitive functions and psychopathology could be shown in both groups. For verbal memory functions (short-term memory, working memory, and learning performance), there was a significant advantage for the aerobic endurance training group. Physical exercise is a feasible, easy-to-implement add-on therapy for schizophrenic patients in a clinical routine setting with positive effects on verbal memory functions. Besides, it seems important to fill the gap between inpatient and outpatient health care, providing physical training supply for this patient group.

4.
Sports (Basel) ; 12(3)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38535727

RESUMO

This study compares the effects of coach verbal encouragement (CVE) and peer verbal encouragement (PVE) on CrossFit-specific one-repetition maximum (1-RM) strength, functional endurance, and psychophysiological assessments. A total of 36 sports science students (18 males, 18 females; mean age: 21.3 ± 0.5 years) participated in a randomized, counterbalanced crossover study in which 1-RM strength and endurance assessment sessions were undertaken under PVE, CVE, and no verbal encouragement (NVE) on separate days. Here, 1-RM strength was assessed through squat, deadlift, and bench press exercises, while endurance was evaluated using 8 min time trials (8MTT). Following the physical assessments, psychophysiological evaluations were conducted using the Borg Rating of Perceived Exertion (RPE) and the Feeling Scale (FS). The findings revealed that, after PVE, all the 1-RM strength test, 8MTT, RPE, and FS values exhibited significant increases compared to those of CVE (p [<0.001-<0.01], r = -0.84 [large]) and NVE (p [<0.001-<0.05], r [-0.43-0.52] [small]). Exceptions were noted in 1-RM-deadlift (p > 0.05, r = -0.43 [small]) and 1-RM-bench-press (p > 0.05, r = -0.43 [small]), where CVE demonstrated higher scores (1-RM-squat, 8MTT, RPE, and FS) (p [<0.001-<0.05], r = -0.64 [large]) in comparison to NVE. In conclusion, the study established that PVE is more impactful than CVE in enhancing CrossFit-specific 1-RM strength, functional endurance, and psychophysiological assessment performance. These findings suggest that coaches/teachers should consider involving their athletes in the reinforcement process for evaluated peers. This collaborative approach may not only optimize performance outcomes but also foster a supportive and motivational training environment.

5.
Horm Mol Biol Clin Investig ; 45(1): 17-25, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38549199

RESUMO

OBJECTIVES: Considering the antioxidant properties of endurance training, this study aimed to investigate the effects of endurance training on serum levels of oxidative stress and structural changes in the kidney tissue of rats exposed to X-ray irradiation. METHODS: In this experimental study, 24 rats weighing 220±20 g were randomly divided into four groups (healthy control, healthy with moderate-intensity continuous training, X-ray control, and X-ray with moderate-intensity continuous training). The two groups of rats were irradiated with 4 Gy X-rays. The two training groups also performed moderate-intensity continuous training for 10 weeks. Twenty-four hour after the last training session, the blood serum of rats was collected and kidney tissue was isolated for stereological studies. RESULTS: In this study, X-ray irradiation of the whole body of rats caused a significant increase in kidney volume, cortex volume, interstitial tissue volume, glomerular volume, and serum level of MDA (p≤0.05), but the medulla volume, volume of proximal tubules (total volume, volume of epithelium, and lumen), volume of distal tubules (total volume, volume of epithelium, and lumen), and the length of the proximal and distal tubules had no effect. In addition, TAC and SOD levels were significantly decreased in the radiation control group. Furthermore, performing endurance training in X-ray-irradiated rats significantly reduced kidney volume, cortex volume, glomerular volume, and serum MDA level (p≤0.05). CONCLUSIONS: Moderate-intensity continuous training can improve the rate of destruction of kidney tissue in rats exposed to X-rays by reducing oxidative stress and subsequently increasing antioxidant capacity.


Assuntos
Antioxidantes , Treino Aeróbico , Humanos , Ratos , Animais , Antioxidantes/farmacologia , Estresse Oxidativo
6.
Cereb Cortex ; 34(3)2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494416

RESUMO

Previous research has confirmed significant differences in regional brain activity and functional connectivity between endurance athletes and non-athletes. However, no studies have investigated the differences in topological efficiency of the brain functional network between endurance athletes and non-athletes. Here, we compared differences in regional activities, functional connectivity, and topological properties to explore the functional basis associated with endurance training. The results showed significant correlations between Regional Homogeneity in the motor cortex, visual cortex, cerebellum, and the training intensity parameters. Alterations in functional connectivity among the motor cortex, visual cortex, cerebellum, and the inferior frontal gyrus and cingulate gyrus were significantly correlated with training intensity parameters. In addition, the graph theoretical analysis results revealed a significant reduction in global efficiency among athletes. This decline is mainly caused by decreased nodal efficiency and nodal local efficiency of the cerebellar regions. Notably, the sensorimotor regions, such as the precentral gyrus and supplementary motor areas, still exhibit increased nodal efficiency and nodal local efficiency. This study not only confirms the improvement of regional activity in brain regions related to endurance training, but also offers novel insights into the mechanisms through which endurance athletes undergo changes in the topological efficiency of the brain functional network.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Giro do Cíngulo , Atletas
7.
J Sports Sci Med ; 23(1): 114-125, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38455431

RESUMO

This study compared the effect of continuous low-intensity aerobic exercise with blood flow restriction (LI-AE-BFR) versus high-intensity interval exercise (HIIE), matching total external mechanical work between conditions, on perceptual (exertion, pain, affective and pleasure) and physiological responses (heart rate [HR], blood lactate [BL] and muscle fatigue). Ten healthy untrained men (25.6 ± 3.78 years old; 75.02 ± 12.02 kg; 172.2 ± 6.76 cm; 24.95 ± 3.16 kg/m²) completed three visits to the laboratory. In visit 1, anthropometry, blood pressure and peak running velocity on the treadmill were measured. In visits 2 and 3, participants were randomly assigned to HIIE or LI-AE-BFR, both in treadmill. HIIE consisted of 10 one-minute stimuli at 80% of peak running velocity interspersed with one-minute of passive recovery. LI-AE-BFR consisted of 20-minutes of continuous walking at 40% of peak running velocity with bilateral cuffs inflated to 50% of arterial occlusion pressure. BL and maximum isometric voluntary contraction (MIVC - fatigue measure) were measured pre- and immediately post-exercise. HR, rating of perceived exertion (RPE), and rating of perceived pain (RPP) were recorded after each stimulus in HIIE and every two minutes in LI-AE-BFR. Affective response to the session, pleasure, and future intention to exercise (FIE) were assessed 10 minutes after the intervention ended. Increases in BL concentrations were greater in HIIE (p = 0.028; r = 0.51). No effects time or condition were reported for MIVC. HR was higher in HIIE at all analyzed time points (p < 0.001; d = 3.1 to 5.2). RPE did not differ between conditions (p > 0.05), while average session RPP was higher in LI-AE-BFR (p = 0.036; r = 0.46). Affective positive response (p = 0.019; d = 0.9) and FIE (p = 0.013; d = 0.97) were significantly higher in HIIE. Therefore, HIIE elicited higher physiological stress, positive affective response, and intention to engage in future exercise bouts compared to LI-AE-BFR.


Assuntos
Exercício Físico , Esforço Físico , Adulto , Humanos , Masculino , Adulto Jovem , Estudos Cross-Over , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Hemodinâmica , Esforço Físico/fisiologia
8.
PeerJ ; 12: e17053, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468641

RESUMO

Background: Disrupted circadian rhythm commonly reported in cancer survivors is closely associated with cancer related fatigue, sleep disturbances and compromised quality of life. As more cancer survivors request non-pharmacological treatment strategies for the management of their chronic sleep-related symptoms, there is a need for meta-analyses of various interventions such as exercise on sleep and circadian rhythm disturbances. Methods: A search for RCT's was conducted in April 2020 and updated in July 2023 using relevant keywords for cancer, sleep, circadian rhythm and exercise interventions on PubMed, Scopus, Web of Science, PEDro and CINAHL. Results: Thirty-six studies were included for qualitative analysis and 26, for meta-analysis. Thirty-five studies analyzed sleep outcomes, while five analyzed circadian rhythm. RCT's studying the effect of aerobic exercise, resistance exercise, combined aerobic and resistance exercise, physical activity, yoga, or tai chi were included. Meta-analysis results showed significant exercise-related improvements on sleep quality assessed by Pittsburgh Sleep Quality index (PSQI) (SMD = -0.50 [-0.87, -0.13], p = 0.008), wake after sleep onset (WASO) (SMD = -0.29 [-0.53, -0.05], p = 0.02) and circadian rhythm, assessed by salivary cortisol levels (MD = -0.09 (95% CI [-0.13 to -0.06]) mg/dL, p < 0.001). Results of the meta-analysis indicated that exercise had no significant effect on sleep efficiency, sleep onset latency, total sleep time and circadian rhythm assessed by accelerometry values. Conclusion: While some sleep and circadian rhythm outcomes (PSQI, WASO and salivary cortisol) exhibited significant improvements, it is still somewhat unclear what exercise prescriptions would optimize different sleep and circadian rhythm outcomes across a variety of groups of cancer survivors. Implication: As exercise does not exacerbate cancer-related circadian rhythm and sleep disturbances, and may actually produce some significant benefits, this meta-analysis provides further evidence for cancer survivors to perform regular exercise.


Assuntos
Sobreviventes de Câncer , Neoplasias , Humanos , Qualidade de Vida , Hidrocortisona , Sono , Neoplasias/complicações , Ritmo Circadiano
9.
Front Public Health ; 12: 1307382, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469269

RESUMO

In recent years, the use of exergaming for physical activity practice has gain in popularity but few is known about the use of augmented reality for physical activity, particularly at moderate to vigorous intensities. The present study examined the use of an exergame in augmented reality for aerobic training in healthy young adults. In a within-subject design, 18 participants (19.8 ± 1.4 years of age) have performed two physical activity sessions playing dodgeball. Indeed, they realized a classical dodgeball session and an exergaming session with an augmented reality version of dodgeball game. Physical loads and intensities were measured with accelerometers, RPE and heart sensors. Enjoyment experienced during the sessions was measured with the short version of the physical activity enjoyment scale questionnaire. Results revealed that both physical load and intensity were appropriate for aerobic training in the two conditions (i.e., classical and exergame in augmented reality) although values were significantly higher in the classical condition. Enjoyment was high in the two conditions with a higher significant value in the classical condition compared to the exergame in augmented reality condition. Put together, these results indicate that an aerobic state can be attained through both physical gameplay and its augmented reality equivalent and was associated to a high level of enjoyment among healthy young adults.


Assuntos
Realidade Aumentada , Jogos de Vídeo , Humanos , Adulto Jovem , Prazer , Jogos Eletrônicos de Movimento , Felicidade
10.
Front Aging ; 5: 1356954, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38523671

RESUMO

Exercise has been shown to improve physical function, mitigate aspects of chronic disease and to potentially alter the trajectory of age-related onset of frailty and sarcopenia. Reliable and valid preclinical models are necessary to elucidate the underlying mechanisms at the intersection of age, exercise, and functional decline. The purpose of this study was to compare, head to head, the effects of two common pre-clinical models of endurance exercise: high intensity interval training (HIIT) and voluntary wheel running (VWR). The hypothesis was that a prescribed and regimented exercise program, HIIT, would prove to be a superior training method to unregulated voluntary exercise, VWR. To investigate this hypothesis, we evaluated adult (n = 24, designated 10 m, aged 6 months at the beginning of the study, 10 months at its completion) and older adult (n = 18, designated 26 m, aging from 22 months to 26 months over the course of the study) C57BL/6 male mice. These mice were randomly assigned (with selection criteria) to a 13-week program of voluntary wheel running (VWR), high intensity interval training (HIIT), or sedentary control (SED). The functional aptitude of each mouse was determined pre- and post-training using our composite CFAB (comprehensive functional assessment battery) scoring system consisting of voluntary wheel running (volitional exercise and activity rate), treadmill (endurance), rotarod (overall motor function), grip meter (forelimb strength), and inverted cling (whole body strength/endurance). To measure sarcopenia, we tracked body mass, body composition (with EchoMRI), plantar flexor torque (in 10 m), and measured muscle wet mass post-training. Overall, adult CFAB scores decreased while body mass and percent body fat increased as they matured; however, exercise significantly mitigated the changes (p < 0.05) compared to SED. Older adults demonstrated preservation of function (CFAB) and reduced body fat (p < 0.05) compared to SED. To conclude, both types of exercise maintained physical function equally in older mice.

11.
JMIR Hum Factors ; 11: e49808, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488838

RESUMO

BACKGROUND: Home-based aerobic exercise in people with neuromuscular diseases (NMDs) has benefits compared to exercise in the hospital or a rehabilitation center because traveling is often cumbersome due to mobility limitations, and societal costs are lower. Barriers to home-based aerobic exercise include reduced possibilities for monitoring and lack of motivation. To overcome these and other barriers, we developed a mobile health app: Keep on training with ReVi (hereafter referred to as ReVi). OBJECTIVE: We aimed to determine the usability of the ReVi app. METHODS: Patients followed a 4-month, polarized, home-based aerobic exercise program on a cycle or rowing ergometer, with 2 low-intensity sessions and 1 high-intensity session per week supported by the ReVi app. The app collected training data, including heart rate and ratings of perceived exertion, provided real-time feedback on reaching target intensity zones, and enabled monitoring via an online dashboard. Physiotherapists instructed patients on how to use the ReVi app and supervised them during their training program. Patients and physiotherapists separately evaluated usability with self-developed questionnaires, including 9 questions on a 5-point Likert scale, covering the usability elements efficiency, effectiveness, and satisfaction. RESULTS: Twenty-nine ambulatory adult patients (n=19 women; mean age 50.4, SD 14.2 years) with 11 different slowly progressive NMDs participated. Both patients and physiotherapists (n=10) reported that the app, in terms of its efficiency, was easy to use and had a rapid learning curve. Sixteen patients (55%) experienced 1 or more technical issue(s) during the course of the exercise program. In the context of effectiveness, 23 patients (81%) indicated that the app motivated them to complete the program and that it helped them to exercise within the target intensity zones. Most patients (n=19, 70%) and physiotherapists (n=6, 60%) were satisfied with the use of the app. The median attendance rate was 88% (IQR 63%-98%), with 76% (IQR 69%-82%) of time spent within the target intensity zones. Four adverse events were reported, 3 of which were resolved without discontinuation of the exercise program. CONCLUSIONS: The usability of the ReVi app was high, despite the technical issues that occurred. Further development of the app to resolve these issues is warranted before broader implementation into clinical practice.


Assuntos
Aplicativos Móveis , Doenças Neuromusculares , Telemedicina , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Exercício Físico , Terapia por Exercício , Doenças Neuromusculares/terapia
12.
Neurosci Lett ; 828: 137752, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38552868

RESUMO

BACKGROUND: Exercise training showed beneficial effects on brain. The purpose of the present study is to evaluate the effect of six weeks of high-intensity interval training (HIIT) and Endurance training (ET) with calcitonin gene-related peptide (CGRP) receptor antagonist on the expression of genes involved in mitochondrial dynamics and apoptosis in hippocampal tissue of male Wistar rats. METHODS: In this study, forty-two healthymale Wistar rats (8-week) were randomly divided into 6 groups (n = 7) as follow; 1) Control; 2) HIIT which performed 6 weeks of HIIT; 3) ET which performed 6 weeks of endurance training; 4) CGRPi received 10 mg/kg CGRP receptor antagonist every day at the last 2 weeks; 5) CGRPi-HIIT performed HIIT and received CGRP receptor antagonist; 6) CGRPi-ET performed ET and received CGRP receptor antagonist. Real-time PCR (2-ΔΔCT) and western blotting were employedto measure the expression of genes and protein, respectively. RESULTS: HIIT and ET significantly increased Bcl-2, Pgc-1α, Sirt3, and Nrf-1 gene expression in the hippocampal tissue (p < 0.05, p < 0.01, p < 0.01, and p < 0.001, respectively). ET-CGRPi and HIIT-CGRPi significantly increased Sirt3, Pgc-1α, and Nrf-1 gene expression compared to the control group (p < 0.05, p < 0.01, and p < 0.05, respectively). CONCLUSION: ET and HIIT-induced physiological alterations in the hippocampus. In fact, this modulation showed protective properties in the hippocampusvia up regulation of Bcl-2, Pgc-1α, Nrf-1, and Sirt3 gene expression. CGRPi did not cause gene or protein changes harmful to mitochondrial dynamic balance and apoptosis in the hippocampus of rats.


Assuntos
Dipeptídeos , Treinamento Intervalado de Alta Intensidade , Condicionamento Físico Animal , Quinazolinas , Sirtuína 3 , Ratos , Masculino , Animais , Ratos Wistar , Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina/metabolismo , Dinâmica Mitocondrial , Sirtuína 3/metabolismo , Hipocampo/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Condicionamento Físico Animal/fisiologia
13.
Front Physiol ; 15: 1359119, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444762

RESUMO

Few formulas have been used in exercise physiology as extensively as the Fick formula, which calculates the rate of oxygen consumption (i.e., V.O2) as the product of cardiac output (Q.) and the difference in oxygen content in arterial and mixed venous blood (Δav¯O2). Unfortunately, the physiology of maximum V.O2 (V.O2MAX) is often misinterpreted due to a lack of appreciation for the limitations represented by the oft-ignored superscript annotations in the Fick formula. The purpose of this perspective is to explain the meaning of the superscript annotations and highlight how such annotations influence proper interpretation of V.O2MAX physiology with the Fick formula. First, we explain the significance of the overdots above V.O2 and Q., which indicate a measure per unit of time. As we will show, the presence of an overdot above Q. and lack of one above Δav¯O2 denotes they are different types of ratios and should be interpreted in the context of one another-not in contrast to each other as is commonplace. Second, we discuss the significance of the overline above the "v¯" in Δav¯O2, which indicates the venous sample is an average of blood that comes from mixed sources. The mixed nature of the venous sample has major implications for interpreting the influence of oxygen diffusion and blood flow heterogeneity on V.O2MAX. Ultimately, we give recommendations and insights for using the Fick formula to calculate V.O2 and interpret V.O2MAX physiology.

14.
Front Public Health ; 12: 1302175, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481847

RESUMO

Introduction: This study aimed to investigate the potential of short-term aerobic exercise to mitigate skeletal muscle mitochondrial damage following ambient PM2.5 exposure, and how 12 weeks of endurance training can enhance aerobic fitness to protect against such damage. Methods: Twenty-four male C57BL/6 J mice were split into sedentary (SED, n = 12) and endurance training (ETR, n = 12) groups. The ETR group underwent 12 weeks of training (10-15 m/min, 60 min/day, 4 times/week), confirmed by an Endurance Exercise Capacity (EEC) test. Post-initial training, the SED group was further divided into SSED (SED and sedentary, n = 6) and SPE (SED and PM2.5 + Exercise, n = 6). Similarly, the ETR group was divided into EEX (ETR and Exercise, n = 6) and EPE (ETR and PM2.5 + Exercise, n = 6). These groups underwent 1 week of atmospherically relevant artificial PM2.5 exposure and treadmill running (3 times/week). Following treatments, an EEC test was conducted, and mice were sacrificed for blood and skeletal muscle extraction. Blood samples were analyzed for oxidative stress indicators, while skeletal muscles were assessed for mitochondrial oxidative metabolism, antioxidant capacity, and mitochondrial damage using western blot and transmission electron microscopy (TEM). Results: After 12 weeks of endurance training, the EEC significantly increased (p < 0.000) in the ETR group compared to the SED group. Following a one-week comparison among the four groups with atmospherically relevant artificial PM2.5 exposure and exercise treatment post-endurance training, the EEX group showed improvements in EEC, oxidative metabolism, mitochondrial dynamics, and antioxidant functions. Conversely, these factors decreased in the EPE group compared to the EEX. Additionally, within the SPE group, exercise effects were evident in HK2, LDH, SOD2, and GPX4, while no impact of short-term exercise was observed in all other factors. TEM images revealed no evidence of mitochondrial damage in both the SED and EEX groups, while the majority of mitochondria were damaged in the SPE group. The EPE group also exhibited damaged mitochondria, although significantly less than the SPE group. Conclusion: Atmospherically relevant artificial PM2.5 exposure can elevate oxidative stress, potentially disrupting the benefits of short-term endurance exercise and leading to mitochondrial damage. Nonetheless, increased aerobic fitness through endurance training can mitigate PM2.5-induced mitochondrial damage.


Assuntos
Treino Aeróbico , Condicionamento Físico Animal , Humanos , Masculino , Camundongos , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Condicionamento Físico Animal/métodos , Condicionamento Físico Animal/fisiologia , Resistência Física/fisiologia , Camundongos Endogâmicos C57BL , Mitocôndrias , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Material Particulado/efeitos adversos
15.
Int J Mol Sci ; 25(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38474128

RESUMO

A better understanding of the cellular and molecular mechanisms that are involved in skeletal muscle adaptation to exercise is fundamentally important to take full advantage of the enormous benefits that exercise training offers in disease prevention and therapy. The aim of this study was to elucidate the transcriptional signatures that distinguish the endurance-trained and untrained muscles in young adult males (24 ± 3.5 years). We characterized baseline differences as well as acute exercise-induced transcriptome responses in vastus lateralis biopsy specimens of endurance-trained athletes (ET; n = 8; VO2max, 67.2 ± 8.9 mL/min/kg) and sedentary healthy volunteers (SED; n = 8; VO2max, 40.3 ± 7.6 mL/min/kg) using microarray technology. A second cohort of SED volunteers (SED-T; n = 10) followed an 8-week endurance training program to assess expression changes of selected marker genes in the course of skeletal muscle adaptation. We deciphered differential baseline signatures that reflected major differences in the oxidative and metabolic capacity of the endurance-trained and untrained muscles. SED-T individuals in the training group displayed an up-regulation of nodal regulators of oxidative adaptation after 3 weeks of training and a significant shift toward the ET signature after 8 weeks. Transcriptome changes provoked by 1 h of intense cycling exercise only poorly overlapped with the genes that constituted the differential baseline signature of ETs and SEDs. Overall, acute exercise-induced transcriptional responses were connected to pathways of contractile, oxidative, and inflammatory stress and revealed a complex and highly regulated framework of interwoven signaling cascades to cope with exercise-provoked homeostatic challenges. While temporal transcriptional programs that were activated in SEDs and ETs were quite similar, the quantitative divergence in the acute response transcriptomes implicated divergent kinetics of gene induction and repression following an acute bout of exercise. Together, our results provide an extensive examination of the transcriptional framework that underlies skeletal muscle plasticity.


Assuntos
Treino Aeróbico , Transcriptoma , Masculino , Adulto Jovem , Humanos , Resistência Física/fisiologia , Músculo Esquelético/metabolismo , Exercício Físico/fisiologia
16.
Sports (Basel) ; 12(2)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38393273

RESUMO

(1) Background: There is a lack of data on the long-term training characteristics and performance markers of elite young female endurance athletes. The aim of this study was to present the training load (ECOs), as well as the evolution of the anthropometric values and performance of three elite U23 female triathletes over a season. (2) Methods: General training data and performance data relating to the swimming, cycling, and running legs of the 2021 season were described. The training intensity distribution (TID) was presented using the triphasic model, while the training load was based on the ECO model. An anthropometric analysis was also conducted in accordance with the ISAK standards. (3) Results: Triathletes increased their VO2max in cycling (6.9-10%) and running (7.1-9.1%), as well as their power and speed associated with the VO2max (7.7-8.6% in cycling and 5.1-5.3% in running) and their swimming speed associated with the lactate thresholds (2.6-4.0% in LT2 and 1.2-2.5% in LT1). The triathletes completed more than 10 h of weekly average training time, with peak weeks exceeding 15 h. The average TID of the three triathletes was 82% in phase 1, 6% in phase 2, and 12% in phase 3. A decrease in the sum of skinfolds and fat mass percentage was observed during the season in the three triathletes, although the last measurement revealed a stagnation or slight rise in these parameters. (4) Conclusions: The triathletes performed a combination of two training periodization models (traditional and block periodization) with a polarized TID in most of the weeks of the season. Improvements in performance and physiological parameters were observed after the general preparatory period as well as a positive body composition evolution throughout the season, except at the end, where the last measurement revealed stagnation or a slight decline. This study can be useful as a general guide for endurance coaches to organize a training season with female U23 triathletes.

17.
J Physiol Sci ; 74(1): 8, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331728

RESUMO

The athlete's paradox phenomenon involves the accumulation of intramuscular triglycerides (IMTG) in both insulin-resistant and insulin-sensitive endurance athletes. Nevertheless, a complete understanding of this phenomenon is yet to be achieved. Recent research indicates that lactate, a common byproduct of physical activity, may increase the accumulation of IMTG in skeletal muscle. This is achieved through the activation of G protein-coupled receptor 81 (GPR81) leads to the suppression of the cyclic adenosine monophosphate-protein kinase A (cAMP-PKA) pathway. The mechanism accountable for the increase in mitochondrial content in skeletal muscle triggered by lactate remains incomprehensible. Based on current research, our objective is to explore the role of the GPR81-inhibited cAMP-PKA pathway in the aggregation of IMTG and the increase in mitochondrial content as a result of prolonged exercise. The GPR81-cAMP-PKA-signaling pathway regulates the buildup of IMTG caused by extended periods of endurance training (ET). This is likely due to a decrease in proteins related to fat breakdown and an increase in proteins responsible for fat production. It is possible that the GPR81-cAMP-PKA pathway does not contribute to the long-term increase in mitochondrial biogenesis and content, which is induced by chronic ET. Additional investigation is required to explore the possible hindrance of the mitochondrial biogenesis and content process during physical activity by the GPR81-cAMP-PKA signal.


Assuntos
Treino Aeróbico , Humanos , Ratos , Animais , Triglicerídeos , Resistência Física/fisiologia , Músculo Esquelético/metabolismo , Insulina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Lactatos/metabolismo
18.
Front Neurol ; 15: 1274809, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38385033

RESUMO

Introduction: Fatigue and poor balance are frequent and severe problems in multiple sclerosis (MS) that may interact. Endurance training is known to be effective on fatigue. This study aims to test if balance training is more effective against MS fatigue. Methods: A randomised crossover trial was run, recruiting 31 MS people (21 women; median age: 46 years, range: 30-64; median EDSS: 4, range: 2.5-5). Participants received balance and endurance training alternately (15 one-to-one sessions, 5 days/week) and were assessed before (T0), after (T1), and 30 days after treatment ended (T2). The Modified Fatigue Impact Scale (MFIS) with scores linearised through Rasch analysis was the primary outcome (the lower the measure, the better the condition, i.e., the lower the fatigue symptoms). The Equiscale balance scale and posturography (EquiTest) were used to assess balance. Linear mixed-effects models with ANOVA were used for significance testing. Results: Thirteen participants had no carryover effect and were included in the primary analysis. Fatigue significantly changed across the three time points (F2,58 = 16.0; p < 0.001), but no difference across treatments was found. Altogether, both treatments significantly improved the MFIS measure at T1 (95%CI: -1.24 logits; mean: -1.67 to -0.81 logits) and T2 (95%CI: -1.04; mean: -1.49 to -0.60) compared to T0 (95%CI: -0.51; mean: -0.95 to -0.08; p ≤ 0.001). Equiscale and posturography highlighted balance improvement after balance training but not after endurance training. Conclusion: Balance and endurance training could similarly reduce fatigue in MS patients in the short term. However, only balance training also improved balance in MS.

19.
Sci Rep ; 14(1): 4102, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374149

RESUMO

The effects of long-term omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation during endurance training on tryptophan (Trp) metabolism and mental state of healthy individuals have not been evaluated so far. Concentrations of plasma Trp, its metabolites and IL-6 were assessed in 26 male runners before and after a 12-week training program combined with supplementation of n-3 PUFAs (O-3 + TRAIN group) or medium chain triglycerides (MCTs; TRAIN group). After the 12-week program participants' mood before and after stress induction was also assessed. The effects of the same supplementation protocol were evaluated also in 14 inactive subjects (O-3 + SEDEN group). Concentrations of 3-hydroxykynurenine (3-HK) and picolinic acid (PA) significantly increased only in the O-3 + TRAIN group (p = 0.01; [Formula: see text] = 0.22 and p = 0.01; [Formula: see text]= 0.26). Favorable, but not statistically significant changes in the concentrations of kynurenic acid (KYNA) (p = 0.06; [Formula: see text]= 0.14), xanthurenic acid (XA) (p = 0.07; [Formula: see text]= 0.13) and 3-hydroxyanthranilic acid (3-HAA) (p = 0.06; [Formula: see text]= 0.15) and in the ratio of neurotoxic to neuroprotective metabolites were seen also only in the O-3 + TRAIN group. No changes in mood and IL-6 concentrations were observed in either group. Supplementation with n-3 PUFAs during endurance training has beneficial effects on Trp's neuroprotective metabolites.Trial registry: This study was registered at ClinicalTrials.gov with identifier NCT05520437 (14/07/2021 first trial registration and 2018/31/N/NZ7/02962 second trial registration).


Assuntos
Treino Aeróbico , Ácidos Graxos Ômega-3 , Humanos , Masculino , Ácidos Graxos Ômega-3/metabolismo , Triptofano/metabolismo , Interleucina-6 , Triglicerídeos , Suplementos Nutricionais
20.
J Appl Physiol (1985) ; 136(3): 555-566, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38234292

RESUMO

Ventricular-vascular coupling in endurance athletes remains incompletely understood. The purpose of this study was to determine the ascending aortic impedance in endurance athletes and explore its associations with traditional cardiovascular measurements. In 15 young male endurance runners and 19 young healthy men, time-resolved (CINE) two-dimensional (2-D) phase-contrast MRI quantified the ascending aortic flow while the pressure waveform was simultaneously collected via a generalized transfer function. The aortic impedance modulus and phase were calculated in the frequency domain while characteristic impedance (ZcF) was calculated by averaging moduli between the 4th and 8th heart rate (HR) harmonics. Stroke volume (SV), left ventricular (LV) morphometry, double product, aortic compliance, and total peripheral resistance (TPR) were also measured. Endurance athletes had higher SV, slower HR, greater LV end-diastolic volume and mass, and lower double product than sedentary participants (all P < 0.05). ZcF was significantly lower in athletes than in sedentary participants (73.3 ± 19.2 vs. 93.4 ± 19.0 dyn·s/cm5, P = 0.005). Furthermore, ZcF was negatively correlated with SV (r = -0.691) and aortic compliance (r = -0.601) but was positively correlated with double product (r = 0.445) and TPR (r = 0.458; all P < 0.05). Multivariate analysis revealed that ZcF was the strongest predictor of SV followed by TPR and HR (adjusted R2 = 0.788, P < 0.001). Therefore, our findings collectively suggest that LV afterload quantified by aortic ZcF is significantly lower in endurance athletes than in sedentary adults. The lower pulsatile LV afterload may contribute to greater SV in endurance athletes.NEW & NOTEWORTHY This is the first study to investigate aortic impedance with the noninvasive, simultaneous recordings of aortic pressure using SphygmoCor XCEL and flow using phase-contrast MRI. We found that the characteristic impedance (Zc) is significantly lower in endurance athletes than sedentary adults, is the strongest predictor of stroke volume (SV), and is inversely associated with aortic compliance. These findings suggest that aortic impedance is a key determinant of the ventricular-vascular coupling adapted to long-term training in endurance athletes.


Assuntos
Atletas , Função Ventricular Esquerda , Adulto , Humanos , Masculino , Impedância Elétrica , Função Ventricular Esquerda/fisiologia , Volume Sistólico/fisiologia , Imageamento por Ressonância Magnética , Resistência Física/fisiologia
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