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1.
Am J Physiol Lung Cell Mol Physiol ; 324(6): L825-L835, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37014821

RESUMEN

Band 3 protein is a Cl-/[Formula: see text] transporter on the red blood cell (RBC) surface with an important role in CO2 excretion. Greater band 3 expression by roughly 20% is found in people with the GP.Mur blood type. Intriguingly, a disproportional percentage of those with GP.Mur excel in field-and-track sports. Could higher band 3 activity benefit an individual's physical performance? This study explored the impact of GP.Mur/higher band 3 expression on ventilation and gas exchange during exhaustive exercise. We recruited 36 nonsmoking, elite male athletes (36.1% GP.Mur) from top sports universities to perform incremental exhaustive treadmill cardiopulmonary exercise testing (CPET). We analyzed CPET data with respect to absolute running time and to individual's %running time and %maximal O2 uptake. We found persistently higher respiratory frequencies and slightly lower tidal volume in GP.Mur athletes, resulting in a slightly larger increase of ventilation as the workload intensified. The expiratory duty cycle (Te/Ttot) was persistently longer and inspiratory duty cycle (Ti/Ttot) was persistently shorter for GP.Mur subjects throughout the run. Consequently, end-tidal pressure of carbon dioxide ([Formula: see text], a surrogate marker for alveolar and arterial CO2 tension-[Formula: see text] and [Formula: see text]) was lower in the GP.Mur athletes during the early stages of exercise. In conclusion, athletes with GP.Mur and higher band 3 expression hyperventilate more during exercise in a pattern that uses a greater fraction of time for expiration than inspiration to increase the rate of CO2 excretion than increased tidal volume. This greater ventilation response reduced Pco2 and may help to extend exercise capacity in high-level sports.NEW & NOTEWORTHY Higher expression of the Cl-/[Formula: see text] transporter band 3 anion exchanger-1 (AE1) on the red blood cell membrane, as in people with the GP.Mur blood type, increases the rate of CO2 excretion during exercise.


Asunto(s)
Dióxido de Carbono , Intercambio Gaseoso Pulmonar , Humanos , Masculino , Dióxido de Carbono/metabolismo , Intercambio Gaseoso Pulmonar/fisiología , Respiración , Pulmón/metabolismo , Espiración
2.
Biol Sport ; 37(4): 389-403, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33343073

RESUMEN

The aim of this study was to provide reference data of variation in external training loads for weekly periods within the annual season. Specifically, we aimed to compare the weekly acute load, monotony, and training strain of accelerometry-based measures across a professional soccer season (pre-season, first and second halves of the season) according to players' positions. Nineteen professional players were monitored daily for 45 weeks using an 18-Hz global positioning system to obtain measures of high metabolic load distance (HMLD), impacts, and high intensity accelerations and decelerations. Workload indices of acute load, training monotony, and training strain were calculated weekly for each of the measures. The HMLD had greater training strain values in the pre-season than in the first (p ≤ 0.001; d = 0.793) and second halves of the season (p ≤ 0.001; d = 0.858). Comparisons between playing positions showed that midfielders had the highest weekly acute load of HMLD (6901 arbitrary units [AU]), while central defenders had the lowest (4986 AU). The pre-season period was associated with the highest acute and strain load of HMLD and number of impacts, with a progressive decrease seen during the season. In conclusion, coaches should consider paying greater attention to variations in HMLD and impacts between periods of the season and between players to individualize training accordingly.

3.
J Med Ultrasound ; 27(1): 26-32, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31031532

RESUMEN

OBJECTIVE: The purpose of this study is to compare the diagnostic performances of strain elastography (SE), shear wave elastography (SWE), and traditional ultrasound (US) features in diagnosing thyroid nodules. SUBJECTS AND METHODS: This study included 185 adult patients with thyroid nodules who underwent conventional gray-scale US, SE, and SWE. SE was scored using a four-pattern elastographic scoring (ES) system. SWE values were presented as mean SWE values and standard derivation using Young's modules. The optimal cutoff values of the mean SWE values for predicting malignancy were determined using receiver operating characteristic (ROC) curve analysis. We used logistic regression models to test elastography as a novel significant predictor for the diagnosis of malignant nodules. The diagnostic performance of elastography parameters was compared with a traditional trained model. RESULTS: Malignant thyroid nodules were stiffer for SE (ES patterns 1 and 2/3 and 4) and mean SWE values (4/17; 51.0 ± 24.4 kPa) than for benign nodules (114/50; 33.1 ± 25.2 kPa) (P < 0.01). In ROC curve analyses, a mean SWE value of 32 kPa was the optimal cutoff point, with diagnostic performance measures of 81% sensitivity, 65% specificity, a 23% positive predictive value (PPV), and 96% negative predictive value (NPV). In multivariate logistic regression, the mean SWE value (≥32 kPa) was an independent predictor for malignancy (odds ratio: 16.8; 95% confidence interval [CI]: 3.6-78.3). However, after the addition of SE and SWE to traditional US features, the C-statistic was not significantly increased compared to the traditional model (0.88, 95% CI: 0.81-0.94 vs. 0.91, 0.85-0.97, P = 0.4). CONCLUSION: In this study, we confirmed SWE as an independent predictor for malignant thyroid nodules. However, in comparing the new extended elastography model to our previous prediction model, the new extended model showed no significant difference in the diagnostic performance.

4.
J Strength Cond Res ; 32(11): 3276-3284, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29084097

RESUMEN

Chen, CH, Ye, X, Wang, YT, Chen, YS, and Tseng, WC. Differential effects of different warm-up protocols on repeated sprints-induced muscle damage. J Strength Cond Res 32(11): 3276-3284, 2018-The purpose of this investigation was to examine whether adding a set of hamstring resistance exercise or dynamic stretching to a regular running-based warm-up before a bout of repeated sprints provides protective effects against the sprinting-induced muscle damage. Twelve elite tennis players participated in this study. After the familiarization, subjects completed 3 separate randomly sequenced experimental visits, during which 3 different warm-up interventions were performed before the muscle-damaging protocol (12 sets of 30-m maximal repeated sprints): 5 minutes of running (control); control with single leg slide curl (SLC); and control with active hamstring stretching (AHS). Before, immediately (POST0), 1 day (POST1), and 2 days after (POST2) the sprints, hip flexion passive range of motion, hamstring muscle thickness and pennation angle, muscle stiffness, and knee flexion concentric peak torque were measured. Repeated sprints have induced muscle damage in all 3 visits. For AHS, the muscle thickness and stiffness values at POST2 were significantly lower than those of other 2 protocols. In addition, the decrements of concentric strength at POST0, POST1, and POST2 for AHS were also significantly less than those of control and SLC. Therefore, adding a set of dynamic hamstrings stretching to a regular warm-up protocol before repeated sprints has protective effect on the sprinting-induced muscle damage. Athletes whose competitions are densely scheduled (e.g., tennis player in a tournament) may take advantage of this strategy to facilitate muscle recovery from the potential muscle damage, thus, to get maximal recovery for the subsequent competitions.


Asunto(s)
Músculos Isquiosurales/lesiones , Carrera/lesiones , Ejercicio de Calentamiento , Adolescente , Adulto , Atletas , Estudios Cruzados , Femenino , Músculos Isquiosurales/fisiología , Cadera , Humanos , Rodilla , Masculino , Rango del Movimiento Articular , Reproducibilidad de los Resultados , Carrera/fisiología , Tenis , Torque , Adulto Joven
5.
Biol Sport ; 35(3): 269-275, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30449945

RESUMEN

To examine whether adding preconditioning hamstring resistance exercises to a regular warm-up prior to a repeated sprinting exercise provides protection against the sprinting-induced muscle damage. Ten female soccer players (mean ± SD age: 21.3 ± 4.5yrs; height: 171.34 ± 8.29 cm; weight: 68.53 ± 11.27 kg) participated in this study. After the familiarization visit, the subjects completed three separate randomly sequenced experimental visits, during which three different warm-up interventions were performed before the muscle-damaging protocol (12 sets of 30-m maximal repeated sprints): 1. Regular running and static stretching (Control); 2. Control with hyperextensions (HE); 3. Control with single leg Romanian deadlift (SLRD). Before (Pre), immediately (Post0), 24 hours (24hr), and 48 hours after (48hr) the sprints, hamstring muscle thickness, muscle stiffness, knee flexion eccentric peak torque, knee extension concentric peak torque, and functional hamstring to quadriceps ratios were measured. Repeated sprints have induced muscle damage (e.g., an average of 42% knee flexion eccentric strength reduction) in all three conditions. After the SLRD, hamstring muscle thickness decreased from 24hr to 48hr (p < 0.001). Additionally, muscle stiffness and eccentric strength for the SLRD showed no difference from baseline at 24hr and 48hr, respectively. When compared with the SLRD at 48hr, the muscle stiffness and the eccentric strength were greater and lower, respectively, in other protocols. The SLRD protocol had protective effect on sprinting-induced muscle damage markers than other protocols. Athletes whose competitions/training are densely scheduled may take advantage of this strategy to facilitate muscle recovery.

6.
BMC Complement Altern Med ; 16: 87, 2016 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-26931120

RESUMEN

BACKGROUND: Tai Chi Chuan (TCC) is known to be a good calisthenics for people. This study examined the relationship between pulse harmonics and autonomic nervous modulation in TCC practitioners. METHODS: Power spectral measures of right pulse wave and heart rate variability (HRV) measures were compared between TCC practitioners and control subjects. Correlation analyses between pulse harmonics and HRV measures were performed using linear regression analysis. RESULTS: At baseline, the total power of pulse (TPp), powers of all individual pulse harmonics, normalized power of the 1(st) harmonics (nPh1) of TCC practitioners were greater, while the normalized power of the 4(th) pulse harmonics (nPh4) of TCC practitioners was smaller, than those of the controls. Similarly, the baseline standard deviation (SD(RR)), coefficient of variation (CV(RR)), and normalized high-frequency power (nHFP) of RR intervals were smaller, while the normalized very low-frequency power (nVLFP) and low-/high- frequency power ratio (LHR) were larger in the TCC practitioners. The TCC age correlated significantly and negatively with nPh1, and nearly significantly and negatively with nPh2 in the TCC practitioners. Thirty min after TCC exercise, the percentage changes in mRRI, SDRR, TP, VLFP were decreased, while the percentage changes in HR, ULFP, nLFP, and Ph2 were increased, relative to the controls. Correlation analysis shows that the %Ph2 correlates significantly and negatively with %mRRI and significantly and positively with %HR. CONCLUSION: The TCC practitioners had increased baseline total power of pulse and the 1(st) and 2(nd) pulse harmonics, and decreased power of the 4(th) pulse harmonics, along with decreased vagal modulation and increased sympathetic modulation. After TCC exercise, the power of the 2(nd) harmonics of TCC practitioners was increased which might be related to the increase in HR due to decreased vascular resistance after TCC exercise.


Asunto(s)
Ejercicio Físico/fisiología , Frecuencia Cardíaca , Pulso Arterial , Taichi Chuan , Resistencia Vascular/fisiología , Adulto , Factores de Edad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistema Nervioso Simpático/fisiología , Nervio Vago/fisiología
7.
Chin J Physiol ; 58(1): 9-18, 2015 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-25687487

RESUMEN

The H-reflex is dependently modulated during isometric and anisometric muscle actions. However, the manner of the H-reflex modulation during dynamic muscle movements in relation to ageing is less stated in the literature. This study was designed to investigate the effects of ageing on soleus (SOL) H-reflex modulation during dynamic muscle actions. Twenty young (24 ± 4 years of age) and 20 older adults (73 ± 5 years of age) voluntarily participated in the study. The SOL H-reflex was measured during passive and active shortening and lengthening muscle actions in a sitting position. The older group showed a lower ratio of the maximal amplitude of H-reflex to M-wave (SOL Hmax/Mmax) during the passive lengthening than that during the passive shortening (shortening: 0.40 ± 0.22 vs. lengthening: 0.15 ± 0.10, P < 0.05), whereas the SOL Hmax/Mmax ratio of the young group was significantly higher during the shortening than that during the lengthening contractions at maximal effort (shortening: 0.51 ± 0.26 vs. lengthening: 0.37 ± 0.18, P < 0.05). These results suggested different modulations of group Ia afferent inputs to the SOL motoneurons during passive and active dynamic muscle actions between young and older adults.


Asunto(s)
Envejecimiento/fisiología , Reflejo H/fisiología , Contracción Muscular/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Electromiografía , Femenino , Humanos , Masculino
8.
J Med Biol Eng ; 35(2): 178-187, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25960706

RESUMEN

Posterior acoustic shadowing (PAS) can bias breast tumor segmentation and classification in ultrasound images. In this paper, half-contour features are proposed to classify benign and malignant breast tumors with PAS, considering the fact that the upper half of the tumor contour is less affected by PAS. Adaptive thresholding and disk expansion are employed to detect tumor contours. Based on the detected full contour, the upper half contour is extracted. For breast tumor classification, six quantitative feature parameters are analyzed for both full contours and half contours, including standard deviation of degree (SDD), which is proposed to describe tumor irregularity. Fifty clinical cases (40 with PAS and 10 without PAS) were used. Tumor circularity (TC) and SDD were both effective full- and half-contour parameters in classifying images without PAS. Half-contour TC [74 % accuracy, 72 % sensitivity, 76 % specificity, 0.78 area under the receiver operating characteristic curve (AUC), p > 0.05] significantly improved the classification of breast tumors with PAS compared to that with full-contour TC (54 % accuracy, 56 % sensitivity, 52 % specificity, 0.52 AUC, p > 0.05). Half-contour SDD (72 % accuracy, 76 % sensitivity, 68 % specificity, 0.81 AUC, p < 0.05) improved the classification of breast tumors with PAS compared to that with full-contour SDD (62 % accuracy, 80 % sensitivity, 44 % specificity, 0.61 AUC, p > 0.05). The proposed half-contour TC and SDD may be useful in classifying benign and malignant breast tumors in ultrasound images affected by PAS.

9.
Opt Express ; 22(5): 5183-95, 2014 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-24663858

RESUMEN

We introduce a type of LED light-gauge steel frame lamp with an adjustable illumination light field that does not require a diffusion plate. Base on the Monte Carlo ray tracing method, this lamp has a good glare rating (GR) of 17.5 at 3050 lm. Compared with the traditional LED light-gauge steel frame lamp (without diffusion plate), the new type has low GR. The adjustability of the illumination light field could improve the zebra effect caused by the inadequate illumination light field of the lamp. Meanwhile, we adopt the retinal image analysis to discuss the influence of GR on vision. High GR could reflect stray light on the retinal image, which will reduce vision clarity and hasten the feeling of eye fatigue.

10.
Sci Rep ; 14(1): 10144, 2024 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698185

RESUMEN

Arterial pulse wave velocity (PWV) is recognized as a convenient method to assess peripheral vascular stiffness. This study explored the clinical characteristics of hand PWV (hPWV) and hand pulse transit time (hPTT) in healthy adults (sixty males = 42.4 ± 13.9 yrs; sixty-four females = 42.8 ± 13.9 yrs) voluntarily participated in this study. The arterial pulse waveform and the anatomical distance from the radial styloid process to the tip of the middle finger of both hands were recorded in the sitting position. The hPWV was calculated as the traversed distance divided by hPTT between those two points. Male subjects showed significantly greater hPWV, systolic blood pressure, and pulse pressure than age-matched female subjects, while the hPTT was not significantly different between genders. Multiple linear regression analysis showed that gender is a common determinant of hPWV and hPTT, and that age and heart rate (HR) were negatively correlated with hPWV and hPTT, respectively. We conclude that male subjects have greater hPWV than female subjects. Ageing is associated with decreased hPWV, while increased HR is associated with a smaller hPTT. The hPWV and hPTT might be used as non-invasive indices to characterise the ageing and arterial stiffness of peripheral blood vessels.


Asunto(s)
Presión Sanguínea , Mano , Frecuencia Cardíaca , Análisis de la Onda del Pulso , Rigidez Vascular , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Mano/fisiología , Rigidez Vascular/fisiología , Presión Sanguínea/fisiología , Frecuencia Cardíaca/fisiología , Voluntarios Sanos
11.
Chronobiol Int ; 41(4): 530-538, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38421010

RESUMEN

This study aimed to investigate the effects of shift work on sleep quality, cardiovascular function, and physical activity (PA) levels in Taiwanese police officers. Twenty-one male police officers aged 26.9 ± 4.1 years old located in Taipei voluntarily participated in this study. The participants completed the resting heart rate (HR) and hemodynamic variables (e.g. blood pressure, BP) before and after day-time (DTW) and night-time (NTW) shift work phases (5 working days and 2 resting days for each phase). Additionally, an actigraphy was administered to measure PA and sleep patterns in the last 3 working days. The average total sleep time and sleep efficiency were 278.5 ± 79. 6 min and 72.9 ± 10%, respectively, in the NTW phases, which were significantly lower than that in the DTW phases. A comparison of the PA characteristics between the two phases revealed that a lower proportion of moderate-vigorous PA (1.2 ± 0.8%) and a greater proportion of sedentary behaviour PA (74.8 ± 6.4%) was found in the NTW phases. The results of hemodynamic measures demonstrated that the police officers have significantly elevated systolic BP by 3.3% and diastolic BP by 3.9% after the NTW phases. Furthermore, the NTW phases exhibited a significantly higher percentage change ratio of systolic BP and diastolic BP compared to the DTW phases. Compared with the DTW phases, the NTW phase was significantly more likely to report higher decreasing parasympathetic-related HR variability with a range of -5.9% to -7.8%. In conclusion, night-time shift work resulted in negative physiological changes leading to adverse effects on the health and well-being of Taiwanese police officers.


Asunto(s)
Presión Sanguínea , Ritmo Circadiano , Frecuencia Cardíaca , Policia , Tolerancia al Trabajo Programado , Humanos , Masculino , Adulto , Taiwán , Frecuencia Cardíaca/fisiología , Presión Sanguínea/fisiología , Tolerancia al Trabajo Programado/fisiología , Ritmo Circadiano/fisiología , Calidad del Sueño , Sueño/fisiología , Ejercicio Físico/fisiología , Adulto Joven , Horario de Trabajo por Turnos , Actigrafía
12.
J Hum Kinet ; 92: 73-85, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38736601

RESUMEN

This study examined relationships among players' physical characteristics, match external loads, and heart rate recovery (HRR) during match substitutions in a congested fixture of an overseas futsal training camp. Eleven under-20 national futsal players' anthropometric characteristics (age, body height, body mass, % fat, and % muscle) and physical fitness [HRmax, VO2max, maximal aerobic speed (MAS) during the 30-15 intermittent fitness test (IFT)] were determined. Additionally, locomotion profiles during field play and HRR sitting on the bench were recorded during five matches. A repeated-measures analysis of variance and Pearson's correlation coefficient were used for statistical analysis. The results revealed that the overall observed correlations among anthropometry, body composition, physical fitness, and HRR were inconsistent across all the matches and substitutions. However, the numbers of moderate (1.00-1.99 m/s2), moderate-to-high (2.00-2.99 m/s2), and high (3.00-50.00 m/s2) intensities of acceleration presented negative correlations in the last match (r < -0.76; p < 0.05). HRR during match substitutions may have been influenced by uncontrolled factors across all the match play and recovery. HRR measures may be affected mainly by fatigue caused by the accumulation of accelerations throughout a congested fixture during a congested-schedule of a futsal training camp.

13.
Mar Pollut Bull ; 195: 115456, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37683395

RESUMEN

Marine debris is a significant pollution problem affecting the world's oceans. The Marine Debris Governance Platform in Taiwan was established in 2017. It adopts a cross-disciplinary approach and encourages collaboration between the public and private sectors to implement actions aimed at raising social awareness and reducing ocean pollution. Generation and impact of waste due to the support and participation of the public, it is crucial for the successful implementation of waste management and the achievement of policy. This study utilizes questionnaire surveys to investigate the factors that influence public support and participation in the action plan of the marine waste management platform for the entire population of Taiwan. We recovered 1295 valid questionnaires and conducted an in-depth analysis of the public's awareness of the marine environment. In terms of the perceived effectiveness of policies, the public considers the "source reduction" action plan to be the most effective policy. Based on this study, it is recommended that the government utilize environmental education and media communication to effectively convey and promote the various policies associated with the action plans. This should gradually lead the public to develop a more positive awareness of the marine environment and increase their involvement in supporting the government's policies on reducing marine waste and plastic.


Asunto(s)
Contaminación Ambiental , Administración de Residuos , Océanos y Mares , Políticas , Taiwán , Plásticos , Residuos/análisis , Monitoreo del Ambiente
14.
Sci Rep ; 13(1): 18077, 2023 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-37872241

RESUMEN

This study aimed to examine the effect of time of day (TOD) on the acquisition of basketball game actions from dynamic and static visualizations in physical education students (novice practitioners). Participants were quasi-randomly assigned to three treatments (static pictures, enriched static-pictures, or video). Morning and late-afternoon sessions were conducted, involving study phases and immediate-recall tests [game comprehension (GC) test and game performance (GP) test]. Oral temperature (OT) and mood states (MS) were also measured. Compared to the morning, the results revealed that afternoon resulted in higher OT, higher negative MS (e.g., anxiety and fatigue), and lower positive MS (i.e., vigor) in all experimental conditions. Moreover, the results showed that: (a) GC and GP decreased throughout the day (regardless of treatments), (b) GC and GP were better with enriched static-pictures (with arrows) than with static pictures, at both TOD, and (c) the video resulted in better GC and GP than the two static presentations, at both TOD. This study (a) highlights the morning's superiority in the acquisition of motor skills from dynamic and static visualizations, due to mood disturbances and lower arousal levels, and (b) encourages basketball teachers to use video modeling by experts, particularly in the morning, for explaining tactical skills.


Asunto(s)
Baloncesto , Humanos , Destreza Motora
15.
Eur J Appl Physiol ; 112(6): 2363-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21947456

RESUMEN

The purpose of this study was to determine the effects of 12-week Tai Chi (TC) training on the soleus (SOL) H-reflex modulation and plantarflexion muscle strength in older adults. Twenty volunteers were assigned into training (N = 14; 72.2 ± 3.7 years of age) and control (N = 6; 74.2 ± 6.1 years of age) groups. The participants in the TC group practiced Yang style TC 1 h per session, 3 sessions per week, for 12 weeks, guided by a qualified TC instructor. The ratio of the maximal peak-to-peak amplitude of SOL H-reflex (H (max)) to M-wave (M (max)) was determined during bipedal standing under four sensory conditions: stable surface and eyes open (SO), stable surface and eyes closed (SC), unstable surface and eyes open (UO), and unstable surface and eyes closed (UC). The maximal isometric plantarflexion muscle strength was also assessed by using a dynamometer. The results showed that the SOL H (max)/M (max) ratio increased significantly after the 12 weeks of TC training under the SC (37.0%), UO (33.3%) and UC (36.0%) conditions (P < 0.05). The maximal plantarflexion strength also improved significantly after training (19.8%; P < 0.05). In contrast, the control group showed no significant changes in all measurements after the 12 weeks.


Asunto(s)
Adaptación Fisiológica/fisiología , Ejercicio Físico/fisiología , Reflejo H/fisiología , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Taichi Chuan/métodos , Factores de Edad , Anciano , Electromiografía/métodos , Femenino , Humanos , Contracción Isométrica/fisiología , Masculino , Neuronas Motoras/fisiología , Proyectos Piloto
16.
J Hum Kinet ; 81: 73-84, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35291626

RESUMEN

There seems to be a scarcity in literature investigating day-to-day warm-up (WU) variations. We investigated day-to-day variation of psychophysiological responses during Fédération Internationale de Football Association (FIFA) 11+ and dynamic warm-up (DWU) exercises. Twenty-one male collegiate soccer players were randomly assigned to the FIFA 11+ (n = 10) or DWU group (n = 11). Each group performed the assigned WU protocol on three different occasions with a 48-h interval in between. The inter-day variation of the heart rate (HR), time distribution of HR zones, heart rate variability (HRV), estimated energy expenditure (EE), blood lactate (BL) concentration, and the Borg rating of perceived exertion (RPE) were recorded. A two-way repeated measures of analysis of variance was used to compare the differences in chosen variables [group (2) × day (3)]. The coefficient of variation was used to determine the dispersion of the variables over the sessions. The interclass correlation coefficient (ICC) with a two-way random model and a single measure (ICC2,1) was used to determine inter-day reliability. There were no significant differences in time spent at particular HR zones and EE in both groups. The FIFA 11+ exercises showed high reliability of exercise duration, average HR (HRaverage), minimal HR (HRmin), peak HR (HRpeak), and post-exercise RPE. In the DWU group, high reliability was found only in HRaverage, HRpeak, and post-exercise RPE. The FIFA 11+ exercises showed similar EE, exercise HR patterns, BL, and RPE compared to the DWU. The FIFA 11+ program is an intense WU protocol with a characteristically low variation of day-to-day exercise HR and RPE responses.

17.
J Complement Integr Med ; 19(4): 817-826, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34187114

RESUMEN

To date, there is no quantitative review examining the influence of heart rate variability biofeedback (HRV BFB) on the athlete population. Such an undertaking may provide valuable information on the autonomic and respiration responses of athletes when performing HRV BFB. Thus, purpose of this preliminary systematic review and meta-analysis on the effects of HRV BFB on HRV and respiration of athletes. Searches of Springerlink, SportDiscus, Web of Science, PROQUEST Academic Research Library, Google Scholar, and ScienceDirect were conducted for studies that met the following criteria: (1) experimental studies involving athletes that underwent randomized control trial; (2) availability of HRV BFB as a treatment compared with a control (CON)/placebo (PLA); (3) any pre and post HRV variable and/or breathing frequency as dependent variable/s; and, (4) peer-reviewed articles written in English. Four out of 660 studies involving 115 athletes (25 females and 90 males) ages 16-30 years old were assessed in this review. Preliminary findings suggest the promising ability of HRV BFB to improve respiratory mechanics in athlete population. More work is needed to determine the autonomic modulatory effect of HRV BFB in athletes.

18.
PeerJ ; 10: e13557, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669960

RESUMEN

Background: This study explores whether listening to preferred music after a stressful situation affects putting and swinging performance, heart rate (HR), HR variability (HRV), and anxiety among amateur golfers. Methods: Twenty healthy amateur collegiate golfers voluntarily participated in this study (age 20.1 ± 1.17 yrs., height = 173.8 ± 7.74 cm, body weight = 72.35 ± 12.67 kg). Pre- and post-intervention HR and HRV measurements were taken, along with a self-report of the State-Trait Anxiety Inventory (STAI-S) and Triple Factor Anxiety Inventory (TFAI). Participants were exposed to a stressful situation through the Stroop Colour and Word Test (SCWT) and then instructed to perform three golf-practice sessions in a golf simulator, separated by 48-72 hours of recovery, under different conditions: control, pre-task music, and synchronised music. Results: No significant difference was identified between the experimental conditions for swinging (in terms of total distance (p = 0.116), carry distance (p = 0.608), speed of the ball (p = 0.819), and launch angle (p = 0.550) and putting performance (the number of successful putts on target (p > 0.05) and distance error between the target and ball (p = 0.122). No main effect for condition and time of intervention, as well as no interaction between these two factors was found for HR, HRV, and STAI-S (p = 0.116). However, the pre and post-intervention percentages of physiological items of the TFAI indicated a large, significant difference in synchronised music trial (p = 0.012, pre-task trial = -1.92% < control trial = 0% < synchronised trial = 4.58%). Conclusions: The results imply that following a stressful situation, listening to preferred music before and/or during golf has no immediate effect on golf performance, anxiety, and psychophysiological responses in collegiate golfers.


Asunto(s)
Música , Humanos , Adolescente , Adulto Joven , Adulto , Ansiedad , Psicofisiología , Percepción Auditiva
19.
BMC Sports Sci Med Rehabil ; 14(1): 138, 2022 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-35871024

RESUMEN

AIM: The purpose of the study was: (i) to analyze the relationships of physiological and locomotor demands between small-sided games (3v3 and 5v5) and official matches (11v11); (ii) to analyze the relationships between small-sided games demands and the physical fitness of youth soccer players. METHODS: The observational study lasted three weeks. In the first week participants performed the 5v5 (50 × 31 and 40 × 25 m) repeatedly over four days. In the third week they repeatedly performed the 3v3 (39 × 24 and 32 × 19 m) over four consecutive days. Twenty youth soccer players (age: 16.8 ± 0.41) were tested twice for their final velocity at 30-15 Intermittent Fitness test (VIFT), peak speed attained at 30-m sprint test (peak speed), and anaerobic speed reserve (ASR). The heart rate responses and locomotor demands were monitored in the SSGs (3v3 and 5v5) and matches (11v11) occurring once a week. The Polar Team Pro was used as the instrument to monitor heart rate and locomotor demands. Three official matches were also monitored during the period. RESULTS: Results revealed no significant correlations (p > 0.05) between small-sided games and match physiological or locomotor demands. However, VIFT and ASR were significantly correlated with distance covered at 5v5 (r = 0.483; p = 0.031; and r = - 0.474; p = 0.035, respectively), average speed (r = 0.474; p = 0.035; and r = - 0.453; p = 0.045, respectively), while VIFT was also significantly correlated with distance covered at Z2 intensity (r = 0.510; p = 0.022). CONCLUSIONS: The results suggest that the physiological and locomotor demands occurring in small-sided games are significantly different from those occurring in official matches. Thus, physiological and locomotor similarities between small-sided games and official matches are scarce. Considering the second purpose of this study, the results suggest that VIFT and ASR are important physical fitness parameters to modulate the amount of distance covered by the players in 5v5, the average pace, and also the distance covered at high intensities.

20.
J Healthc Eng ; 2022: 5135817, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35449856

RESUMEN

Background: Physical conditions are recognized to be optimal after the pre-season (PS) phase in professional sports. Given that blood measures may also reveal variations, which in turn, may present associations with fitness changes. Objective: The aim of this study is to test the changes of blood markers and physical fitness outcomes at the beginning and following the PS phase. Additionally, we aimed also to analyze the associations of training adaptations between blood markers and the physical fitness measures. Methodology. 25 professional male soccer players (28.1 ± 4.6 years old, 2.0 ± 7.8 kg, and 176.7 ± 4.9 cm) were assessed for hematological and biochemical parameters, and physical fitness measures in the baseline and after the phase of PS. Results: Increases in platelets were observed after the PS phase (p = 0.001, η2 = 0.39). Regarding the biochemical parameters, significant increases between PS were found for creatinine (Cre) (p = 0.001, η2 = 0.66), alkaline phosphatase (ALP) (p = 0.001, η2 = 0.79), C-Reactive Protein (CRP) (p = 0.001, η2 = 0.74), cortisol (C) (p = 0.001, η2 = 0.63), and testosterone (T) (p = 0.001, η2 = 0.76), whereas significant decreases were found for albumin (Alb) (p = 0.004, η2 = 0.29), and calcium corrected (Ca Corr.) (p = 0.002, η2 = 0.32). Moderate correlations were found between albumin and the 5-meter linear sprint split (r = -0.44 (95%CI: -0.71; -0.05)) and CRP (r = -0.48 (95%CI: -0.74; -0.10)). Moderate correlations were found between VAMEVAL and hemoglobin (r = 0.44 (95%CI: 0.05; 0.71)). Conclusions: The overall physical fitness measures improved after the PS phase. Also, significant variations (decreases/increases) were observed for the case of biomchemical and hematological outcomes. Coaches should carefully consider the adaptative changes observed in blood parameters as the changes in whole organism and metabolism after specific critical phases as the PS in professional players. Thus, optimal management of stimulus/recovery can be warranted to minimize illness and injury rate and to follow the direction and dynamics of adaptative changes.


Asunto(s)
Fútbol , Adulto , Albúminas , Biomarcadores , Ejercicio Físico , Prueba de Esfuerzo , Humanos , Masculino , Aptitud Física , Adulto Joven
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