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1.
Front Sports Act Living ; 6: 1251047, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38406765

RESUMEN

This study aimed to investigate recovery markers among elite climbers following the National Boulder Championship. We assessed maximum isometric hand grip strength (HS), forearm swelling (circumference), delayed soreness in forearm muscles, tiredness, and exercise readiness at several time points: pre-competition, immediately post-competition (within 4 min after their last effort), and 12, 24, 48, and 60 h post-competition. Maximum isometric hand grip strength decreased by 6.38 ± 1.32% (p = 0.006) post-12 h, returning to pre-competition values post-24 h (all p > 0.05). Forearm circumference (FC) increased 1.78 ± 1.77% (p < 0.001) post-competition, returning to pre-competition values post-12 h (all p > 0.05). Forearm pain (FP) increased post-competition (p = 0.002) and post-12 h (p < 0.001), returning to pre-competition values post-24 h (all p > 0.05). Tiredness increased post-competition (p < 0.001), post-12 h (p < 0.001), and post-24 h (p < 0.001), returning to pre-competition values post-48 h (all p > 0.05). Climbing readiness was reduced post-competition (p < 0.001), post-12 h (p < 0.001), post-24 h (p < 0.001), and post-48 h (p = 0.005), only returning to pre-competition values post-60 h (p = 0.189). Visual analysis of individual data pointed out a relatively small variability in the HS and FC markers, while FP, tiredness, and readiness exhibited larger individual variations. These findings indicate that different recovery patterns exist for the analyzed markers, suggesting that athletes may require up to 60 h after a competition to fully recover and regain their ability to face new competitive challenges.

2.
Metabolites ; 13(3)2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36984775

RESUMEN

The mechanisms responsible for the similar muscle growth attained with high- and low-load resistance training (RT) have not yet been fully elucidated. One mechanism is related to the mechanical stimulus and the level of motor unit recruitment; another mechanism is related to the metabolic response. We investigated the electromyographic signal amplitude (sEMG) and the general metabolic response to high-load RT (HL) and low-load resistance training (LL). We measured muscle thickness by ultrasound, sEMG amplitude by electromyography, and analysis of metabolites expressed through metabolomics. No differences were observed between the HL and LL groups for metabolic response and muscle thickness. A greater amplitude of sEMG was observed in the HL group. In addition, a correlation was observed between changes in muscle thickness of the vastus lateralis muscle in the HL group and levels of the metabolites carnitine, creatine, 3-hydroxyisovalerate, phenylalanine, asparagine, creatine phosphate, and methionine. In the LL group, a correlation was observed between changes in muscle thickness of the vastus lateralis muscle and levels of the metabolites acetoacetate, creatine phosphate, and oxypurinol. These correlations seem to be related to the characteristics of activated muscle fibers, the metabolic demand of the training protocols used, and the process of protein synthesis.

3.
Biomedicines ; 11(2)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36831101

RESUMEN

Purpose: Considering that the CHRNA7 and CHRFAM7A genes can be modulated by acute or chronic inflammation, and exercise modulates inflammatory responses, the question that arises is whether physical exercise could exert any effect on the expression of these genes. Thus, the aim of this work is to identify the effects of different types of exercises on the expression of the CHRNA7, CHRFAM7A and tumor necrosis factor-α (TNF-α) in leukocytes of healthy normal weight (HNW), and overweight with type 2 diabetes (OT2D) individuals. Methods: 15 OT2D and 13 HNW participants (men and women, from 40 to 60 years old) performed in a randomized crossover design three exercise sessions: aerobic exercise (AE), resistance exercise (RE) and combined exercise (CE). Blood samples were collected at rest and post-60-min of the exercise sessions. The leukocytes were the analysis of the CHRNA7, CHRFAM7A and (TNF-α) gene expression. Results: At baseline, OT2D had higher CHRFAM7A and TNF-α expression compared to HNW. No statistical differences were observed between groups for CHRNA7; however, the HNW group presented almost twice as many subjects with the expression of this gene (24% vs. 49%). Post exercise, the CHRFAM7A increased in AE, RE and CE for HNW, and in AE and CE for OT2D. There was no significant difference for TNF-α and CHRNA7 expression between any type of exercise and group. Conclusions: Our study shows that OT2D individuals presented higher baseline expression of TNF-α and CHRFAM7A, besides evidence of decreased CHRNA7A expression in leukocytes when compared with HNW. On the other hand, acutely physical exercise induces increased CHRFAM7A expression, especially when the aerobic component is present.

4.
Lasers Med Sci ; 37(9): 3713-3722, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36274079

RESUMEN

The aim of this study was to evaluate the time course of the effects of far-infrared emitting fabric (FIR) on neuromuscular performance of knee extensor over 120 h and to investigate whether the use of FIR affects semen. This is a crossover, randomized, double-blind, and placebo-controlled trial split into neuromuscular and fertility assessments. Four (28.8 ± 4.7 years old) and six (29 ± 3.9 years old) healthy, resistance-trained males completed all neuromuscular and fertility assessments, respectively. In neuromuscular assessments, for five consecutive days, the participants underwent neuromuscular tests in an isokinetic dynamometer (maximal isometric voluntary contraction (MVC) and fatigue test) every 24 h in both conditions (FIR and Placebo). In fertility assessments, participants performed three semen collections: Baseline, FIR, and Placebo. FIR and Placebo collections were performed after five consecutive days of use of the pants. Conventional parameters and sperm DNA fragmentation were evaluated. In the FIR condition, the participants showed significant differences in total work at 96 h (p < 0.001; Cohen's d = 3.73), 120 h (p = 0.01; Cohen's d = 2.65), and pre-MVC at 120 h (p = 0.02; Cohen's d = 2.15) when compared to Placebo. FIR did not significantly (p > 0.05) affect the conventional semen parameters or sperm DNA fragmentation compared to Baseline or Placebo. FIR improved the knee extensor neuromuscular performance of healthy resistance-trained individuals, with 112.4 ± 7.8 h accumulated, and did not affect their seminal parameters (conventional or sperm DNA fragmentation), with 113.1 ± 10.2 h accumulated.


Asunto(s)
Ejercicio Físico , Músculo Esquelético , Masculino , Humanos , Adulto Joven , Adulto , Proyectos Piloto , Semen , Fatiga Muscular , Fertilidad , Contracción Muscular
5.
Front Psychol ; 13: 870561, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36312128

RESUMEN

Background: The present study compared the effects of a traditional resistance training (TRT) and resistance training combined with cognitive task (RT + CT) on body composition, physical performance, cognitive function, and plasma brain-derived neurotrophic factor (BNDF) levels in older adults. Methods: Thirty community-dwelling older adults were randomized into TRT (70.0 ± 8.1; 25% men) and RT + CT (66.3 ± 4.6; 31% men). Exercise groups performed a similar resistance training (RT) program, twice a week over 16 weeks. Cognitive Training involved performing verbal fluency simultaneously with RT. Exercise sessions (eight resistance exercises) were performed 2-3 sets, 8-15 repetitions at 60%-70% of 1-repetition maximum (1RM). Body composition, physical function, cognitive performance, and BDNF levels were assessed before and after intervention period. Results: The physical performance was similarly improved in response to both TRT and RT + CT (p = 0.001). However, exclusive improvements on cognitive function (p < 0.001) and BDNF levels (p = 0.001) were observed only after RT + CT. Conclusion: The RT program associated with a cognitive task, improved physical and cognitive performance in healthy older adults.

6.
Artículo en Inglés | MEDLINE | ID: mdl-36078774

RESUMEN

The aim was to identify whether 16 weeks of combined training (Training) reduces blood pressure of hypertensive older adults and what the key fitness, hemodynamic, autonomic, inflammatory, oxidative, glucose and/or lipid mediators of this intervention would be. Fifty-two individuals were randomized to either 16 weeks of Training or control group who remained physically inactive (Control). Training included walking/running at 63% of V˙O2max, three times per week, and strength training, consisting of one set of fifteen repetitions (seven exercises) at moderate intensity, twice per week. Both groups underwent a comprehensive health assessment at baseline (W0) and every four weeks, for 16 weeks total. p-value ≤ 0.05 was set as significant. Training did not reduce blood pressure. It increased V˙O2max after eight weeks and again after 16 weeks (~18%), differently from the Control group. At 16 weeks, Training increased strength (~8%), slightly reduced body mass (~1%), and reduced the number of individuals with metabolic syndrome (~7%). No other changes were observed (heart rate, carotid compliance, body composition, glycemic and lipid profile, inflammatory markers and oxidative profile, vasoactive substances, heart rate variability indices). Although Training increased cardiorespiratory fitness and strength, Training was able to reduce neither blood pressure nor a wide range of mediators in hypertensive older adults, suggesting other exercise interventions might be necessary to improve overall health in this population. The novelty of this study was the time-course characterization of Training effects, surprisingly demonstrating stability among a comprehensive number of health outcomes in hypertensive older adults, including blood pressure.


Asunto(s)
Capacidad Cardiovascular , Hipertensión , Entrenamiento de Fuerza , Anciano , Capacidad Cardiovascular/fisiología , Ejercicio Físico/fisiología , Humanos , Hipertensión/terapia , Lípidos
7.
Lasers Med Sci ; 37(5): 2527-2536, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35146580

RESUMEN

The aim of this study was to verify if exposure to the far-IR emitted by fabric (FIR) is able to improve the neuromuscular performance of the knee extensors of resistance-trained males regardless of changes of the temperature. It is a crossover, randomized, double-blind, and placebo-controlled trial. Fourteen resistance-trained males (age: 24.3 ± 4 years; body mass: 82.8 ± 11.3 kg; height: 176.3 ± 4.2 cm) were randomly assigned to one of initial conditions: FIR (n = 7) or placebo (n = 7). After 4 days, the participants were submitted to neuromuscular tests in an isokinetic dynamometer (maximal isometric voluntary contraction (MVC) and fatigue test). After a week of washout, participants performed the other condition. We measured peak torque (Nm), total work (J), fatigue index (%), root mean square (mV), median frequency (Hz), and temperature (°C) of thigh. The FIR was worn for 82 ± 19 h before the experimental session, totaling 317 ± 74 kJ of energy irradiation. There was a significant increase (p < 0.05) for pre-MVC (318.5 ± 68.7 Nm) and post-MVC (284.1 ± 58.2 Nm), and a trend (p = 0.055) for significant increase for total work (4,122.2 ± 699.8 J) on FIR condition regardless of none change on temperature and electromyographic (EMG) signals. FIR improved the neuromuscular performance of knee extensors in resistance-trained males regardless of changes on temperature and EMG. The present results suggest that the FIR could optimize the neuromuscular performance with 82 ± 19 h of wear.


Asunto(s)
Contracción Muscular , Fatiga Muscular , Adulto , Electromiografía , Fatiga , Humanos , Contracción Isométrica , Masculino , Músculo Esquelético , Torque , Adulto Joven
8.
Am J Physiol Regul Integr Comp Physiol ; 320(6): R812-R823, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33787348

RESUMEN

The present study analyzed the effects of local ischemia during endurance exercise on neuromuscular fatigue (NMF). Nine cyclists performed, in a counterbalanced order, two separate 4-km cycling time trials (TT) with (ISCH) or without (CONTR) induced local ischemia. NMF was characterized by using isometric maximal voluntary contractions (IMVC), whereas central [voluntary activation (VA)] and peripheral fatigue [peak torque of potentiated twitch (TwPt)] of knee extensors were evaluated using electrically evoked contractions performed before (PRE) and 1 min after (POST) the TT. Electromyographic activity (EMG), power output (PO), oxygen uptake (V̇o2), and rating of perceived exertion (RPE) were also recorded. The decrease in IMVC (-15 ± 9% vs. -10 ± 8%, P = 0.66), VA (-4 ± 3% vs. -3 ± 3%, P = 0.46), and TwPt (-16 ± 7% vs. -19 ± 14%, P = 0.67) was similar in ISCH and CONTR. Endurance performance was drastically reduced in ISCH condition (512 ± 29 s) compared with CONTR (386 ± 17 s) (P < 0.001), which was accompanied by lower EMG, PO, and V̇o2 responses (all P < 0.05). RPE was greater in ISCH compared with CONTR (P < 0.05), but the rate of change was similar throughout the TT (8.19 ± 2.59 vs. 7.81 ± 2.01 RPE.% of total time-1, P > 0.05). These results indicate that similar end-exercise NMF levels were accompanied by impaired endurance performance in ISCH compared with CONTR. These novel findings suggest that the local reduced oxygen availability affected the afferent feedback signals to the central nervous system, ultimately increasing perceived effort and reducing muscle activity and exercise intensity to avoid surpassing a sensory tolerance limit before the finish line.


Asunto(s)
Rendimiento Atlético/fisiología , Isquemia/fisiopatología , Fatiga Muscular/fisiología , Músculo Esquelético/fisiopatología , Adulto , Ciclismo/fisiología , Ejercicio Físico/fisiología , Humanos , Contracción Isométrica/fisiología , Articulación de la Rodilla/fisiología , Articulación de la Rodilla/fisiopatología , Masculino , Músculo Esquelético/fisiología
9.
PLoS One ; 15(8): e0237010, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32780739

RESUMEN

This study analyzed the physiological adjustments caused by the use of the Elevation training mask® (2.0), an airflow restriction mask (ARM) during continuous exercise. Eighteen physically active participants (12 men and 6 women) were randomized to two protocols: continuous exercise with mask (CE-ARM) and continuous exercise without mask (CE). Exercise consisted of cycling for 20 minutes at 60% of maximum power. Metabolic variables, lactate, and gas concentration were obtained from arterialized blood samples at pre and post exercise. Continuous expired gases and myoelectric activity of the quadriceps were performed at rest and during the test. We observed no reduction in oxygen saturation in CE-ARM, leading to lower pH, higher carbon dioxide, and greater hematocrit (all p <0.05). The expired gas analysis shows that the CE-ARM condition presented higher oxygen uptake and expired carbon dioxide concentrations (p <0.05). The CE-ARM condition also presented lower ventilatory volume, ventilatory frequency, and expired oxygen pressure (p <0.05). No changes in electromyography activity and lactate concentrations were identified. We conclude that using ARM does not induce hypoxia and represents an additional challenge for the control of acid-base balance, and we suggest the use of ARM as being suitable for respiratory muscle training.


Asunto(s)
Ejercicio Físico/fisiología , Consumo de Oxígeno/fisiología , Ventilación Pulmonar/fisiología , Adulto , Ejercicios Respiratorios/métodos , Dióxido de Carbono/sangre , Prueba de Esfuerzo/métodos , Femenino , Voluntarios Sanos , Humanos , Hipoxia/metabolismo , Pulmón/metabolismo , Masculino , Máscaras , Oxígeno/sangre , Respiración , Pruebas de Función Respiratoria
10.
PLoS One ; 14(11): e0224801, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31710635

RESUMEN

The objective of the present study was to verify the energy expenditure (EE), energy system contributions and autonomic control during and after an acute low-load or high-load resistance training (RT) protocol to momentary failure (MF) in young adults. Eleven young men (22 ± 3 yrs, 71.8 ± 7.7 kg; 1.75 ± 0.06 m) underwent a randomized crossover design of three knee extension acute protocols: a low-load RT [30% of their maximal strength (1RM); RT30] or a high-load RT (80% of 1RM; RT80) protocol, with all sets being performed to MF; or a control session (Control) without exercise. Participants were measured for EE, energy system contributions, and cardiac autonomic control before, during, and after each exercise session. Exercise EE was significantly higher for RT30 as compared to RT80. Furthermore, post measurements of blood lactate levels and the anaerobic lactic system contribution were significantly greater for RT30 as compared to RT80. In addition, parasympathetic restoration was lower for RT30 as compared to RT80. In conclusion, a low-load (30% 1RM) RT session produced higher EE during exercise than a high-load (80% 1RM) RT session to MF, and may be a good option for fitness professionals, exercise physiologists, and practitioners when choosing the optimal RT protocol that provides more EE, especially for those who want or need to lose weight.


Asunto(s)
Metabolismo Energético/fisiología , Ejercicio Físico/fisiología , Entrenamiento de Fuerza , Frecuencia Cardíaca/fisiología , Humanos , Lactatos/sangre , Masculino , Consumo de Oxígeno/fisiología , Adulto Joven
11.
Eur J Appl Physiol ; 119(7): 1479-1489, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30953177

RESUMEN

OBJECTIVE: This study aimed to verify the acute and prolonged effects of stretch-shortening cycle exercise (SSC) on performance and neuromuscular function following a 4-km cycling time trial (4-km TT). METHODS: On separate days, individuals performed a 4-km TT without any previous exercise (CON), immediately (ACUTE) and 48 h after (PROL) SSC protocol (i.e., 100-drop jumps). Neuromuscular function was measured at baseline SSC (baseline), before (pre-TT) and after (post-TT) 4-km TT. Muscle soreness and inflammatory responses also were assessed. RESULTS: The endurance performance was impaired in both ACUTE (- 2.3 ± 1.8%) and PROL (- 1.8 ± 2.4%) compared with CON. The SSC protocol caused also an acute reduction in neuromuscular function, with a greater decrease in potentiated quadriceps twitch-force (Qtw.pot - 49 ± 16%) and voluntary activation (VA - 6.5 ± 7%) compared for CON and PROL at pre-TT. The neuromuscular function was fully recovered 48 h after SSC protocol. Muscle soreness and IL-10 were elevated only 48 h after SSC protocol. At post-TT, Qtw.pot remained lower in ACUTE (- 52 ± 14%) compared to CON (- 29 ± 7%) and PROL (- 31 ± 16%). CONCLUSION: These findings demonstrate that impairment in endurance performance induced by prior SSC protocol was mediated by two distinct mechanisms, where the acute impairment was related to an exacerbated degree of peripheral and central fatigue, and the prolonged impairment was due to elevated perceived muscle soreness.


Asunto(s)
Fatiga/etiología , Contracción Isométrica , Fatiga Muscular , Resistencia Física , Ejercicio Pliométrico/métodos , Adulto , Fatiga/fisiopatología , Humanos , Interleucinas/sangre , Ácido Láctico/sangre , Masculino , Ejercicio Pliométrico/efectos adversos
12.
PLoS One ; 14(2): e0212115, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30742692

RESUMEN

BACKGROUND: Recent studies have begun to identify the molecular determinants of inter-individual variability of cardiorespiratory fitness (CRF) in response to exercise training programs. However, we still have an incomplete picture of the molecular mechanisms underlying trainability in response to exercise training. OBJECTIVE: We investigated baseline serum and skeletal muscle metabolomics profile and its associations with maximal power output (MPO) gains in response to 8-week of continuous endurance training (ET) and high-intensity interval training (HIIT) programs matched for total units of exercise performed (the TIMES study). METHODS: Eighty healthy sedentary young adult males were randomized to one of three groups and 70 were defined as completers (> 90% of sessions): ET (n = 30), HIIT (n = 30) and control (CO, n = 10). For the CO, participants were asked to not exercise for 8 weeks. Serum and skeletal muscle samples were analyzed by 1H-NMR spectroscopy. The targeted screens yielded 43 serum and 70 muscle reproducible metabolites (intraclass > 0.75; coefficient of variation < 25%). Associations of baseline metabolites with MPO trainability were explored within each training program via three analytical strategies: (1) correlations with gains in MPO; (2) differences between high and low responders to ET and HIIT; and (3) metabolites contributions to the most significant pathways related to gains in MPO. The significance level was set at P < 0.01 or false discovery rate of 0.1. RESULTS: The exercise programs generated similar gains in MPO (ET = 21.4 ± 8.0%; HIIT = 24.3 ± 8.5%). MPO associated baseline metabolites supported by all three levels of evidence were: serum glycerol, muscle alanine, proline, threonine, creatinine, AMP and pyruvate for ET, and serum lysine, phenylalanine, creatine, and muscle glycolate for HIIT. The most common pathways suggested by the metabolite profiles were aminoacyl-tRNA biosynthesis, and carbohydrate and amino acid metabolism. CONCLUSION: We suggest that MPO gains in both programs are potentially associated with metabolites indicative of baseline amino acid and translation processes with additional evidence for carbohydrate metabolism in ET.


Asunto(s)
Biomarcadores/sangre , Entrenamiento Aeróbico , Entrenamiento de Intervalos de Alta Intensidad , Fuerza Muscular/fisiología , Músculo Esquelético/metabolismo , Adolescente , Adulto , Biomarcadores/metabolismo , Capacidad Cardiovascular/fisiología , Entrenamiento Aeróbico/métodos , Entrenamiento de Intervalos de Alta Intensidad/métodos , Humanos , Estudios Longitudinales , Masculino , Metabolómica , Músculo Esquelético/química , Adulto Joven
13.
J Strength Cond Res ; 33(7): 1762-1765, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30204655

RESUMEN

Teodoro, CL, Gáspari, AF, Berton, R, Barbieri, JF, Silva, M, Castaño, LAA, Guimarães, P, and Moraes, AC. Familiarization with airflow-restriction mask during resistance exercise: Effect on tolerance and total volume. J Strength Cond Res 33(7): 1762-1765, 2019-This study investigated whether familiarization with the airflow-restriction mask (AIRfr) increases tolerance and avoids negative effects on performance of resistance exercise (RE). Ten resistance-trained male subjects performed a familiarization session (FAM), followed by 2 testing sessions, with the AIRfr and without airflow restriction (SHAM) in a counterbalanced and randomized cross-over design. The FAM was performed with the same number of sets, load, and level of airflow-restriction as the AIRfr experimental session. Each session consisted of 4 sets of the leg press exercise with 70% 1 repetition maximum until voluntary failure and a 90-second rest interval between sets. During the FAM, 4 of the 10 subjects expressed some intolerance to the use of airflow restriction. Total volume was lower in the FAM than in the AIRfr (p = 0.01) and the SHAM (p = 0.02), whereas no differences were observed between the AIRfr and the SHAM (p = 0.90). The first use of the AIRfr may not be well tolerated by all subjects. However, a familiarization session with the AIRfr avoids negative interferences in the total volume during RE.


Asunto(s)
Ventilación Pulmonar/fisiología , Entrenamiento de Fuerza/métodos , Adulto , Estudios Cruzados , Humanos , Masculino , Descanso , Adulto Joven
15.
J Sports Med Phys Fitness ; 58(6): 923-932, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29877680

RESUMEN

INTRODUCTION: The independent predictor of cardiovascular mortality, central arterial stiffness (CAS), is modulated by exercise depending on type of exercises, arteries assessed, sample features and time to exposure. Thus, this study aim to determine the endurance, resistance and combined exercise effects on CAS over time in humans. EVIDENCE ACQUISITION: MEDLINE database for studies published between January 1st, 1990 and February 3rd, 2015. Studies measuring the effects of exercise on CAS, measured by aortic pulse wave velocity or carotid arterial compliance measured by ultrasound were included. Two independent reviewers extracted the 56 studies meta-analyzed and allocated among type of exercise and time effects categories: acute (10 minutes to 24 hours post-exercise session effect), short-term (interventional studies testing basal CAS from 1 to 24 weeks of exercise) and long-term (cross-sectional studies comparing trained and untrained individuals). EVIDENCE SYNTHESIS: We calculated standard difference in means 95% CIs, applying random or fixed-effects models, according to presence or absence of true heterogeneity, respectively. Endurance exercise reduced CAS in short and long-term analysis (-0.42 [-0.53 to -0.31] and -0.62 [-0.95 to -0.29], respectively), however it did not modify CAS acutely; higher magnitude of reduction occurred in normal weight individuals, with longer duration, higher weekly frequency and continuous (rather than interval) protocols. Resistance exercise increases CAS acutely (0.30 [0.01 to 0.58]) and after long-term (0.47 [0.19 to 0.75]), while short-term resistance exercise did not modify CAS significantly. No significant effect was found for short-term combined exercises and there was not enough number of studies for acute and long-term effects to be meta-analysed. CONCLUSIONS: Endurance and resistance exercise have opposite long-term effects, being beneficial and deleterious, respectively, while the combined exercise showed to be innocuous.


Asunto(s)
Terapia por Ejercicio/métodos , Ejercicio Físico/fisiología , Rigidez Vascular/fisiología , Estudios Transversales , Femenino , Humanos , Masculino , Análisis de la Onda del Pulso , Factores de Tiempo
16.
Eur J Sport Sci ; 18(6): 842-850, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29667537

RESUMEN

The main purpose of this study was to compare the effect of the constant load and self-paced exercise with similar total work on autonomic control after endurance exercise. Ten physically active men were submitted to (i) a maximal incremental exercise test, (ii) a 4-km cycling time trial (4-km TT), and (iii) a constant workload test with identical total external work performed at 4-km TT. Gas exchange was measured throughout the tests, while blood lactate, heart rate, and heart rate variability (HRV) were measured during the passive recovery. Power output measured at the last lap (i.e. 3600-4000 m) of 4-km TT (316 ± 89 W) was statistically higher than power output measured at the end of the constant workload exercise (211 ± 42 W). The 4-km TT produced higher values of blood lactate concentration (8.8 ± 2.1 mmol L-1) than the constant workload test (7.8 ± 2.1 mmol L-1). The heart rate recovery measured at 60 s (constant workload: 37 ± 7 bpm; 4-km TT: 30 ± 6) and 120 s (constant workload: 57 ± 9 bpm; 4-km TT: 51 ± 9 bpm) were higher in the constant workload than in the self-paced exercise. The HRV (i.e. RMSSD30s) was statistically higher in the constant load exercise measured at 120, 420, 450, 480, 540, and 570 s than the self-paced exercise. These findings suggest that the autonomic control responses were dependent of the endurance exercise modalities, with parasympathetic activity being delayed after self-paced exercise, as evidenced by post-exercise heart rate indices.


Asunto(s)
Ejercicio Físico/fisiología , Frecuencia Cardíaca , Sistema Nervioso Parasimpático/fisiología , Adulto , Metabolismo Energético , Prueba de Esfuerzo , Humanos , Ácido Láctico/sangre , Masculino , Consumo de Oxígeno , Adulto Joven
17.
Nutrients ; 10(4)2018 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-29596307

RESUMEN

It remains unclear as to what extent resistance training (RT) can attenuate muscle loss during caloric restriction (CR) interventions in humans. The objective here is to address if RT could attenuate muscle loss induced by CR in obese elderly individuals, through summarized effects of previous studies. Databases MEDLINE, Embase and Web of Science were used to perform a systematic search between July and August 2017. Were included in the review randomized clinical trials (RCT) comparing the effects of CR with (CRRT) or without RT on lean body mass (LBM), fat body mass (FBM), and total body mass (BM), measured by dual-energy X-ray absorptiometry, on obese elderly individuals. The six RCTs included in the review applied RT three times per week, for 12 to 24 weeks, and most CR interventions followed diets of 55% carbohydrate, 15% protein, and 30% fat. RT reduced 93.5% of CR-induced LBM loss (0.819 kg [0.364 to 1.273]), with similar reduction in FBM and BM, compared with CR. Furthermore, to address muscle quality, the change in strength/LBM ratio tended to be different (p = 0.07) following CRRT (20.9 ± 23.1%) and CR interventions (−7.5 ± 9.9%). Our conclusion is that CRRT is able to prevent almost 100% of CR-induced muscle loss, while resulting in FBM and BM reductions that do not significantly differ from CR.


Asunto(s)
Restricción Calórica , Músculo Esquelético/fisiología , Entrenamiento de Fuerza , Anciano , Humanos
18.
PLoS One ; 13(3): e0194776, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29596452

RESUMEN

PURPOSE: We investigated the energy system contributions and total energy expenditure during low intensity endurance exercise associated with blood flow restriction (LIE-BFR) and without blood flow restriction (LIE). METHODS: Twelve males participated in a contra-balanced, cross-over design in which subjects completed a bout of low-intensity endurance exercise (30min cycling at 40% of [Formula: see text]) with or without BFR, separated by at least 72 hours of recovery. Blood lactate accumulation and oxygen uptake during and after exercise were used to estimate the anaerobic lactic metabolism, aerobic metabolism, and anaerobic alactic metabolism contributions, respectively. RESULTS: There were significant increases in the anaerobic lactic metabolism (P = 0.008), aerobic metabolism (P = 0.020), and total energy expenditure (P = 0.008) in the LIE-BFR. No significant differences between conditions for the anaerobic alactic metabolism were found (P = 0.582). Plasma lactate concentration was significantly higher in the LIE-BFR at 15min and peak post-exercise (all P≤0.008). Heart rate was significantly higher in the LIE-BFR at 10, 15, 20, 25, and 30min during exercise, and 5, 10, and 15min after exercise (all P≤0.03). Ventilation was significantly higher in the LIE-BFR at 10, 15, and 20min during exercise (all P≤0.003). CONCLUSION: Low-intensity endurance exercise performed with blood flow restriction increases the anaerobic lactic and aerobic metabolisms, total energy expenditure, and cardiorespiratory responses.


Asunto(s)
Circulación Sanguínea , Ejercicio Físico , Ácido Láctico/metabolismo , Consumo de Oxígeno , Adolescente , Adulto , Anaerobiosis , Femenino , Humanos , Ácido Láctico/sangre , Masculino , Adulto Joven
20.
Int J Sports Med ; 39(1): 29-36, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29121681

RESUMEN

The aging process is associated with several changes in the elderly such as the decrease in cardiorespiratory fitness, strength and muscle mass, in addition to chronic low-grade inflammation. Concurrent training with blood flow restriction can be an interesting alternative to improve functional capacity with low mechanical stress in the elderly. The purpose of this study was to compare the inflammatory effects in older individuals submitted to two different protocols of concurrent training. Twenty-two healthy older adults (63.7±3.8 years; 69.8±8.9 kg; 1.6±0.1 m) performed 12 weeks of concurrent training (CT) or concurrent training with blood flow restriction (CTBFR) and the effects on inflammatory markers were analyzed. We found inflammatory behavior for the CTBFR group with a significant difference in serum concentration of C-reactive protein between pre- and post-moment (0.96±0.37 to 1.71±1.45, p=0.049), with no difference between groups, and a time effect in interleukin-6 (pre=0.86±0.43; post=1.02±0.46, p=0.016). We conclude that the CTBFR showed a pro-inflammatory profile after the period of intervention whereas the CT showed the opposite.


Asunto(s)
Inflamación/sangre , Acondicionamiento Físico Humano/métodos , Músculo Cuádriceps/irrigación sanguínea , Anciano , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Femenino , Humanos , Interleucina-10/sangre , Interleucina-6/sangre , Lípidos/sangre , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Resistencia Física/fisiología , Músculo Cuádriceps/anatomía & histología , Flujo Sanguíneo Regional/fisiología , Entrenamiento de Fuerza , Factor de Necrosis Tumoral alfa/sangre
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