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1.
Int J Sports Med ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38857879

RESUMEN

The purpose of this study was to compare the effects of dry needling (DN) intervention on the responses of muscle tone, stiffness, and elasticity, as well as power, pressure pain thresholds, and blood perfusion of the flexor carpi radialis muscle in mixed martial arts (MMA) athletes. Thirty-two trained/developmental men MMA fighters (25.5±4.5 years; 24.5±3 body mass index) participated in a randomized crossover study. Participants underwent a single intervention, receiving both DN and placebo. Laser Doppler flowmetry measured blood perfusion, while a myotonometer assessed the mechanical characteristics of muscle tone, stiffness, and elasticity of the flexor carpi radialis muscle. Pressure pain thresholds (PPT) were measured using an algometer, and maximal forearm muscle force was measured using a hand dynamometer. Outcomes were assessed at baseline, immediately after, and 24 hours and 48 hours post-intervention. A two-way repeated-measures ANOVA revealed significant Intervention*Time interaction for all outcomes: perfusion unit (p<0.001), muscle tone (p<0.001), stiffness (p<0.001), elasticity (p<0.001), PPT (p<0.001) and maximal forearm muscle force (p<0.001). The current study suggests that a single session of DN enhances muscle recovery, increases muscle strength, and improved PPT in MMA athletes. These positive adaptations appear to last up to 48 hours in some variables.

2.
Front Hum Neurosci ; 18: 1362418, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38516307

RESUMEN

This study aimed to explore the relationship between motor skill learning and executive function (EF), with an emphasis on the potential effects of football juggling learning. A randomized controlled trial involving 111 participants aged 17-19 years was conducted. Participants were randomly assigned to either the football juggling learning (FJL) group or a control group. The FJL group underwent 70 sessions of football juggling learning, while the control group engaged in their normal daily activities without any exercise intervention during the same time frame. Both groups were assessed for EF performance and underwent functional magnetic resonance imaging (fMRI) scans before and after the experiment. The executive function test included three tasks, namely, inhibition, working memory, and shifting. The results showed significant improvement in inhibition and shifting in both groups, and the FJL group showed greater improvement in these aspects of EF compared to the control group. Additionally, in comparison to the control group, the FJL group exhibited increased functional connectivity within the frontal, temporal, and cerebellar regions from the pre-test to the post-test. Notably, enhanced functional connectivity between the right superior temporal gyrus (posterior division) and left cerebellum 6 was identified in the FJL group and was associated with improved EF performance induced by football juggling learning. These findings shed light on the potential causal relationship between motor skill learning, EF, and brain plasticity. Importantly, our study provides preliminary evidence supporting the use of motor skill learning, such as football juggling, as a potential avenue for cognitive enhancement.

3.
Eur J Appl Physiol ; 124(5): 1609-1620, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38175273

RESUMEN

PURPOSE: This study aimed to investigate physiological responses, muscle-tendon unit properties of the quadriceps muscle, and mechanical performance after repeated sprint cycling at optimal and 70% of optimal cadence. METHODS: Twenty recreational cyclists performed as first sprint performance cycling test and during subsequent sessions two repeated sprint cycling protocols at optimal and 70% of optimal cadence, in random order. The muscle-tendon unit outcome measures on the dominant leg included muscle thickness, fascicle length (Lf), pennation angle (θp), and stiffness for the rectus femoris (RF), vastus lateralis (VL), and vastus medialis muscle (VM) at baseline, immediately after repeated sprint cycling, and 1-h post-exercise. RESULTS: The results showed an increase in muscle thickness and θp in RF, VL, and VM for both cadences from baseline to immediately after exercise. The Lf decreased in RF (both cadences), while stiffness decreased in RF, VL, and VM at optimal cadence, and in VL at 70% of optimal cadence from baseline to immediately after exercise. CONCLUSION: The present study revealed that the alterations in muscle characteristics were more marked after repeated sprint cycling at optimal cadence compared with a lower cadence most likely as a result of higher load on the muscle-tendon unit at optimal cadence.


Asunto(s)
Ciclismo , Humanos , Masculino , Ciclismo/fisiología , Adulto , Músculo Esquelético/fisiología , Músculo Cuádriceps/fisiología , Músculo Cuádriceps/diagnóstico por imagen , Rendimiento Atlético/fisiología , Contracción Muscular/fisiología , Adulto Joven
4.
Front Physiol ; 14: 1260346, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38156067

RESUMEN

This study aimed to evaluate the test-retest reliability of a sprint performance test with semi-tethered front crawl swimming to indirectly assess the current potential to perform at maximal anaerobic effort in adolescent swimmers. Eight adolescent swimmers participated in this study (gender: females (n = 4) aged 13.0 ± 0.8 years, body height 1.6 ± 0.0 m, body mass 50.1 ± 4.5 kg; and males (n = 4) aged 13.3 ± 1.3 years, body height 1.7 ± 0.1 m, body mass 59.0 ± 8.2 kg. The testing protocol consisted of two trials of 25 m semi-tethered front crawl swimming with maximal effort and with 1 kg resisted isotonic load. Velocity data were recorded automatically by the 1080 Sprint device for 15 m (between 3 m and 18 m). The Fast Fourier Transform algorithm filtered raw instantaneous swimming velocity data in distance (time) function. A third-degree polynomial was used to extract the individual velocity profile, from which the following variables were chosen for test-retest reliability and the assessment of sprint performance: ttrial15, vmax, vmin, tvto max, tvat max, Dto vmax, Dat vmax, fatigue index. Parameters such as vmax, vmin, and ttrial15 were estimated from swimming velocity profiles and considered as reliable. The CV showed low variance <5%; while ICC2,1 demonstrated respectively good (ICC2,1: 0.88), very good (ICC2,1: 0.95), and excellent (ICC2,1: 0.98) rate of relative reliability; and the Bland-Altman index revealed an acceptable agreement (LoA ≤5%) between two measurements. The sprint performance test based on semi-tethered front crawl swimming confirmed that ttrial15, vmax, and vmin were reliable variables to indirectly indicate a potential to perform the maximal anaerobic effort among adolescent swimmers. The evaluation of the swimming velocity profiles allows coaches to monitor the adaptive changes of performance during the training process.

5.
Front Physiol ; 14: 1253140, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37772056

RESUMEN

The main goal was to investigate the effectiveness of cryosauna in preventing the development of delayed onset muscle soreness and to analyze the regenerative changes within muscles after acute fatigue-induced exercises. Thirty-one volunteers were assigned into two groups: 1) an intervention group that participated in cryostimulation after fatigue-induced exercise protocol (CRYO, n = 16) and a control group that performed fatigue-induced exercise protocol, but without any intervention (CONT, n = 15). Main outcome measures include at baseline: blood sample testing (leukocyte content, myoglobin concentration, and creatine kinase activity) and muscle stiffness of lower extremity; immediately after (stiffness), and 24-48-72-96 h post-exercise (blood samples and stiffness). Both groups performed an exercise-induced muscle damage protocol based on repeated countermovement jumps (10 sets, 10 repetitions). The CRYO group underwent a cryosauna (temperature: -110°C, time: 1.5 min per session) intervention during four sessions (i.e., immediately after, 24-48-72 h post-exercise). Leukocyte content was significantly greater 24-48-72 h after exercise in CONT, compared with the CRYO group (p ≤ 0.05 for all), while creatine kinase activity was greater 24-48-96 h in CONT, compared with the CRYO group (p ≤ 0.05 for all). Muscle stiffness increased significantly in rectus femoris, tibialis anterior, and fibula muscle after 48 h post-exercise (p ≤ 0.05 for all), as well as in tibialis anterior and fibula after 72 h post-exercise (p ≤ 0.05 for all) in the CRYO group. Multiple cryosauna was an effective recovery strategy that reduced blood biomarkers and muscle stiffness after exercise-induced muscle damage. Moreover, the development of delayed onset muscle soreness, expressed by a greater muscle stiffness post-exercise, was attenuated to the first 48 h.

6.
PeerJ ; 11: e15671, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37456896

RESUMEN

Objectives: Currently, there are no data on sex differences in the power profiles in sprint track cycling. This cross-section study analyses retrospective data of female and male track sprint cyclists for sex differences. We hypothesized that women would exhibit lower peak power to weight than men, as well as demonstrate a different distribution of power durations related to sprint cycling performance. Design: We used training, testing, and racing data from a publicly available online depository (www.strava.com), for 29 track sprint cyclists (eight women providing 18 datasets, and 21 men providing 54 datasets) to create sex-specific profiles. R2 was used to describe model quality, and regression indices are used to compare watts per kilogram (W/kg) for each duration for both sexes against a 1:1 relationship expected for 15-s:15-s W/kg. Results: We confirmed our sample were sprint cyclists, displaying higher peak and competition power than track endurance cyclists. All power profiles showed a high model quality (R2 ≥ 0.77). Regression indices for both sexes were similar for all durations, suggesting similar peak power and similar relationship between peak power and endurance level for both men and women (rejecting our hypothesis). The value of R2 for the female sprinters showed greater variation suggesting greater differences within female sprint cyclists. Conclusion: The main finding shows female sprint cyclists in this study have very similar relationships between peak power and endurance power as men. Higher variation in W/kg for women in this study than men, within these strong relationships, indicates women in this study, had greater inter-athlete variability, and may thus require more personalised training. Future work needs to be performed with larger samples, and at different levels to optimize these recommendations.


Asunto(s)
Ciclismo , Caracteres Sexuales , Humanos , Masculino , Femenino , Estudios Retrospectivos , Atletas
7.
PLoS One ; 18(5): e0280658, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37235558

RESUMEN

Current convention place peak power as the main determinant of sprint cycling performance. This study challenges that notion and compares two common durations of sprint cycling performance with not only peak power, but power out to 20-min. There is also a belief where maximal efforts of longer durations will be detrimental to sprint cycling performance. 56 data sets from 27 cyclists (21 male, 6 female) provided maximal power for durations from 1-s to 20-min. Peak power values are compared to assess the strength of correlation (R2), and any relationship (slope) across every level. R2 between 15-s- 30-s power and durations from 1-s to 20-min remained high (R2 ≥ 0.83). Despite current assumptions around 1-s power, our data shows this relationship is stronger around competition durations, and 1-s power also still shared strong relationships with longer durations out to 20-min. Slopes for relationships at shorter durations were closer to a 1:1 relationship than longer durations, but closer to long-duration slopes than to a 1:1 line. The present analyses contradicts both well-accepted hypotheses that peak power is the main driver of sprint cycling performance and that maximal efforts of longer durations out to 20-min will hinder sprint cycling. This study shows the importance and potential of training durations from 1-s to 20-min over a preparation period to improve competition sprint cycling performance.


Asunto(s)
Rendimiento Atlético , Ciclismo , Masculino , Humanos , Femenino , Factores de Tiempo
8.
Int J Sports Med ; 44(13): 995-1002, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36690028

RESUMEN

This study aims to investigate morphological and mechanical properties and echogenicity of the patellar tendon (PT) after acute fatigue-induced alterations in sprint track cyclists. Fourteen elite track cyclists participated in this study. The exercise protocol consisted of three maximal start accelerations (over a distance of 62.5 m), one maximal start acceleration (at both 125 m and 250 m), and sprints from the standing start. Immediately after testing all measurements, PT stiffness and thickness were set at 5-10-15-20 mm distal from the apex of the patella and 5-10 mm proximal to the tibial tuberosity. CSA was set at proximal, middle, and distal, while echogenicity was at proximal and distal points. The results showed significant increases in PT stiffness at all reference points after start acceleration (p<0.001). PT thickness showed similar results for stiffness, except for location placed at TT-5 (p<0.001). CSA increased significantly in proximal, middle, and distal regions (p<0.001), while echogenicity of the tendon increased in proximal and distal regions (p<0.001) after start acceleration. Regional-dependent alterations of PT thickness and stiffness may be related to anatomical and physiological mechanisms due to acute isometric contraction in the initial phase of standing start. Tendon echogenicity might be also useful in monitoring tendon mechanical properties and defining acute fatigue-induced changes.


Asunto(s)
Ligamento Rotuliano , Humanos , Ligamento Rotuliano/diagnóstico por imagen , Fatiga Muscular , Fenómenos Biomecánicos/fisiología , Tibia , Contracción Isométrica
9.
Res Sports Med ; 31(6): 787-801, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35179412

RESUMEN

This study aimed to investigate the acute effect of repeated climbing actions on functional and morphological measures of the shoulder girdle. Fifteen male indoor climbers participated in this study. All the climbers declared route level 6a+, as the best climbing grade (French climbing grade scale). Functional (range of motion - ROM and muscle strength), and morphological measurements (muscle/tendon stiffness and thickness) after a repeated climbing exercise protocol were analysed. The ROM and muscle strength showed significant decreases from baseline to Immediate-Post (IA) as well as significant increases from IA to 1 h-Post for all movements (p ≤ .001 for all). Muscle stiffness showed significant increases from baseline to IA after as well as significant decreases from IA to 1 h-Post for all muscles (p ≤ .001 for all). However, the thickness showed significant increases from baseline to IA for supraspinatus tendon and muscle thickness and occupation ratio (p ≤ .001 for all), while a significant decrease was observed in acromiohumeral distance (p ≤ .001). Significant decreases from IA to 1 h-Post were found for muscles/tendons and occupation ratio (p ≤ .001 for all), while a significant increase for AHD (p ≤ .001). Our data demonstrated acute alterations in tendon thickness due to acute signs of implement symptom in climbers.

10.
PeerJ ; 10: e14409, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36523451

RESUMEN

Background: Indoor climbing involves overloading the shoulder girdle, including the rotator cuff and upper trapezius muscles. This on the field study aimed to investigate the effects of repeated climbing bouts on morphological and mechanical measures of the upper trapezius muscle. Materials and Methods: Fifteen experienced male climbers participated in the study. Rate of perceived exertion (RPE), blood lactate concentration ([La-]b), and stiffness and thickness over four points of the upper trapezius were assessed before and after a repeated climbing exercise. The procedure for the climbing exercise consisted of five climbs for a total time of 5-minutes per climb, followed by a 5-minute rest. Results: The analysis showed an increase from baseline to after the 3rd climb (p ≤ 0.01) for RPE and after the 5th climb for [La-]b (p ≤ 0.001). Muscle stiffness and thickness increased at all points (1-2-3-4) after the 5th climb (p ≤ 0.01). We found spatial heterogeneity in muscle stiffness and thickness; muscle stiffness was the highest at Point 4 (p ≤ 0.01), while muscle thickness reached the highest values at points 1-2 (both p ≤ 0.01). Moreover, the analysis between the dominant and non-dominant shoulder showed greater stiffness after the 1st climb at Point 1 (p = 0.004) and after the 5th climb at Point 4 (p ≤ 0.001). Conclusions: For muscle thickness, the analysis showed significant changes in time and location between the dominant and the non-dominant shoulder. Bilateral increases in upper trapezius muscle stiffness and thickness, with simultaneous increases in RPE and blood lactate in response to consecutive climbs eliciting fatigue.


Asunto(s)
Músculos Superficiales de la Espalda , Masculino , Humanos , Músculos Superficiales de la Espalda/fisiología , Resistencia Física/fisiología , Ácido Láctico , Hombro/fisiología , Ejercicio Físico
11.
Res Sports Med ; : 1-14, 2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36134907

RESUMEN

This study aimed to investigate an acute effect of foam rolling and tissue flossing of the Triceps Surae muscle on Achilles tendon stiffness, jump height and sprint performance at different time points. The participants were academic athletes (n = 32) aged between 22 and 24 years; randomly allocated into two groups: foam rolling (ROLL) and tissue flossing (FLOSS). The participants were tested at baseline and 5-min, 15-min, 30-min, 45-min, and 60-min after ROLL and FLOSS for Achilles tendon stiffness (ATstiffeness) at three reference locations: (1) tendon's origin, (2) ankle joint height and (3) intermuscular septum of the gastronomies muscle; countermovement jump (CMJ); and sprint performance at 15-m (SPRINT15 m). The analysis of stiffness revealed a significant decrease in ATstiffness from baseline to Post-60 (p ≤ 0.001) for three locations in the FLOSS group (p ≤ 0.001). In FLOSS, a significant increase was observed from Post-15 to Post-60 (all p≤0.001) in CMJ. We found also a significant decrease in SPRINT15 m in FLOSS in all-time points (p ≤ 0.001), however, SPRINT15 m decreased in Post-5 min, Post-15 min, and Post-30 min (p ≤ 0.001 for all) in ROLL. The current study suggested that both groups enhanced performance up to 60 min after the intervention, caused by mitigating excessive stiffness.

12.
Front Hum Neurosci ; 16: 926346, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36034121

RESUMEN

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social impairment, restricted interests, and repetitive stereotyped behaviors. At present, its pathogenesis has not been fully understood. Various methods are used for clinical treatment and intervention, among which physical activity (PA) intervention also has an obvious effect. This study has used bibliometric methods and visual analysis methods to analyze 885 studies of PA intervention in ASD from 2003 to 2022 in the Web of Science (WoS) database in order to provide theoretical support for the follow-up research on the effect of PA with ASD. The main findings of this study are as follows. First, the literature on PA interventions in ASD research showed a growing trend. The leading institution in this field is the University of Delaware, forming a core group of authors represented by authors such as Sean Healy and Carol Curtin et al. Second, the research focus of this research area mainly includes PA interventions for children and adolescents with ASD. PA can improve symptoms such as stereotyped behaviors and motor function in patients with ASD as well as can reduce childhood obesity rates and improve quality of life. Third, skill, youth, prevalence, and meta-analysis systematic reviews were found. It is the long-term concern and focus of researchers. In conclusion, the current research is only a short-term analysis, and it is not possible to verify the long-term effect; thus, future data analysis should evaluate and explore the long-term effects of PA interventions on ASD including cohort and longitudinal study types focused on the rehabilitation of patients with ASD. Moreover, testing the sustainability of benefits for children with ASD and constructing a multidimensional exercise integrated intervention model are the main directions for future research in this field.

13.
Tomography ; 8(4): 1726-1734, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35894010

RESUMEN

We aimed to investigate clinical and ultrasound signs of shoulder overuse injuries in professional bullfighters; side-to-side differences (dominant vs. non-dominant); and to determine potential differences according to bullfighters' categories. An observational cross-sectional study was conducted. Thirty professional and active bullfighters were assessed. A bilateral ultrasound assessment of the subacromial bursa, long biceps head tendon (LHBT), and rotator cuff was performed to determine the presence of bursitis, subluxation, partial or total tendon rupture, tenosynovitis, or calcification. Supraspinatus tendon thickness was measured. Finally, a battery of clinical orthopedic tests (Yergason, Jobe, infraspinatus, Gerber, and bursa tests) were also performed. Most identified ultrasound findings were located in the dominant side, being the presence of bursitis (n = 9; 30%), LHBT tenosynovitis (n = 8; 26.7%), and subscapularis tendon calcification (n = 5; 16.7%) the most prevalent. No side-to-side or between-categories differences were found for supraspinatus tendon thickness (all, p > 0.05). The most frequent positive signs were the infraspinatus test (40.0%), Gerber lift-off test (33.3%), and bursitis, Jobe, and Yergason tests (all, 26.7%). Ultrasound signs were commonly found at LHBT, subacromial bursa, and rotator cuff in professional bullfighters without difference between categories and sides. No side-to-side or between-categories differences were found. Positive clinical test signs suggestive of bursitis, LHBT, and rotator cuff tendinopathy were frequently observed.


Asunto(s)
Bursitis , Calcinosis , Lesiones del Manguito de los Rotadores , Lesiones del Hombro , Tenosinovitis , Bursitis/diagnóstico por imagen , Bursitis/epidemiología , Estudios Transversales , Humanos , Prevalencia , Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Lesiones del Manguito de los Rotadores/epidemiología , Hombro/diagnóstico por imagen , Lesiones del Hombro/diagnóstico por imagen , Lesiones del Hombro/epidemiología , Ultrasonografía
14.
PLoS One ; 17(7): e0270871, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35789336

RESUMEN

The goal of our study was to investigate the relative and absolute intra-rater and inter-rater reliability of ultrasound assessment of patellar tendon (PT) thickness assessed over four locations, in track cyclists and soccer players. Fifteen male elite track cyclists and 15 male elite soccer players participated. Tendon thickness was measured over 4 locations placed at 5-10-15-20 mm inferior to the apex of the patella by two experienced examiners. Each examiner took two US images for the test measurements with a 10-min rest period. After a 30-min period, the subjects underwent a retest measurements that were also repeated 1-week after. A two-way analysis of variance revealed a significant group x location interaction on PT thickness for Examiner 1 (p = .001, η2 = .81) and Examiner 2 (p = 0.001, η2 = 0.78). Intra-rater reliability ranged from good to excellent (ICC2,k ≥ 0.75), whereas inter-rater reliability was good (ICC2,k ≥ 0.75) in both groups. Ultrasonographic assessment of PT was found to be a reliable method to assess tendon thickness. The middle location of the PT (corresponding to 15 and 20 mm) can be considered the most reliable spot to measure PT thickness. The PT thickness was larger among track cyclists than soccer players, with larger differences over the distal location (15 mm). Ultrasonographic assessment of PT was found to be a reliable method to assess tendon thickness. The middle location of the PT corresponding to 15 mm and 20 mm can be considered the most reliable area to measure PT thickness.


Asunto(s)
Ligamento Rotuliano , Fútbol , Humanos , Masculino , Ligamento Rotuliano/diagnóstico por imagen , Reproducibilidad de los Resultados , Tendones/diagnóstico por imagen , Ultrasonografía/métodos
15.
Artículo en Inglés | MEDLINE | ID: mdl-33802582

RESUMEN

The goal of our study was to examine the muscle activity of the shoulder girdle after isokinetic fatigue, which may simulate muscle activities commonly occurring during specific sport-related activities in recreational overhead asymptomatic athletes. We hypothesized that exercise-induced fatigue, reported after isokinetic protocols, may cause a decrease in the median frequency (MF) of the upper trapezius (UT), infraspinatus (IS), and deltoid muscles. Twenty-four male overhead volleyball (n = 8), handball (n = 8), and tennis (n = 8) athletes participated in this study. All subjects were without shoulder injury history. The surface electromyography (SEMG) was collected on the right (dominant) side of the shoulder girdle muscles in the following order: UT, IS and anterior (DA), and posterior deltoideus (DP). The fatigue protocol consisted of three sets of 32 maximum isokinetic concentric contractions while performing shoulder internal and external rotation at an isokinetic speed of 120 o/s. The resultant difference in median frequency (ΔMF) values consistently dropped after the fatiguing tasks across all recorded muscles, in terms of the initial MF (MFINI = 65.1 ± 1.1 Hz) and final MF (MFFIN = 57.9 ± 0.9 Hz), and the main effect of time was significant (F(1,22) = 43.15, p < 0.001). MF values decreased mostly for IS (ΔMFIS = -9.9 ± 1.6 Hz) and DP (ΔMFPD = -9.5 ± 1.9 Hz) muscles, while DA and UT showed smaller changes (ΔMFDA = -6.9 ± 1.5 Hz) and (ΔMFUT = -3.2 ± 1.3 Hz). The results of our study show a meaningful contribution in determining increased fatigue of the shoulder girdle muscles during repeated isokinetic internal-external rotation protocols. We have also demonstrated a significant decrease in MF in all examined muscles, especially IS and DA.


Asunto(s)
Articulación del Hombro , Hombro , Atletas , Electromiografía , Fatiga , Humanos , Masculino , Músculo Esquelético , Manguito de los Rotadores
16.
Front Physiol ; 11: 607208, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33381054

RESUMEN

Track cyclists are required to perform short- and long-term efforts during sprint and endurance race events, respectively. The 200 m flying sprint races require maximal power output and anaerobic capacity, while the 4,000 m pursuit cyclists demand a high level of aerobic capacity. Our goal was to investigate spatial changes in morphological and mechanical properties displayed using 3D topographical maps of the quadriceps muscle and tendons after 200 m flying start and 4,000 m individual pursuit race in elite track cyclists. We hypothesized a non-uniform distribution of the changes in the quadriceps muscle stiffness (QMstiff), and acute alterations in quadriceps tendon (QTthick) and patellar tendon (PTthick) thickness. Fifteen men elite sprint and 15 elite men endurance track cyclists participated. Sprint track cyclists participated in a 200 m flying start, while endurance track cyclists in 4,000 m individual pursuit. Outcomes including QTthick (5-10-15 mm proximal to the upper edge of the patella), PTthick (5-10-15-20 mm inferior to the apex of the patella)-using ultrasonography evaluation, QMstiff, and quadriceps tendon stiffness (QTstiff) were measured according to anatomically defined locations (point 1-8) and patellar tendon stiffness (PTstiff)-using myotonometry, measured in a midway point between the patella distal and the tuberosity of tibial. All parameters were assessed before and after (up to 5 min) the 200 m or 4,000 m events. Sprint track cyclists had significantly larger QTthick and PTthick than endurance track cyclists. Post-hoc analysis showed significant spatial differences in QMstiff between rectus femoris, vastus lateralis, and vastus medialis in sprint track cyclists. At before race, sprint track cyclists presented significantly higher mean QTthick and PTthick, and higher QMstiff and the QTstiff, as compared with the endurance track cyclists. The observed changes in PTThick and QTThick were mostly related to adaptation-based vascularity and hypertrophy processes. The current study suggests that assessments using both ultrasonography and myotonometry provides crucial information about tendons and muscles properties and their acute adaptation to exercise. Higher stiffness in sprint compared with endurance track cyclists at baseline seems to highlight alterations in mechanical properties of the tendon and muscle that could lead to overuse injuries.

17.
Artículo en Inglés | MEDLINE | ID: mdl-32854323

RESUMEN

Background: Both physical exercise and cognitive training can effectively improve executive functions in older adults. However, whether physical activity combined with cognitive training is more effective than a single intervention remains controversial. The aim of this study was to perform a meta-analysis to evaluate the effect of combined physical and cognitive interventions on executive functions in older adults aged 65-80 years old. Methods: Randomized controlled trials of combined physical and cognitive interventions on executive functions in older adults were searched using the Web of Science, Elsevier Science, PubMed, EBSCO, Springer-Link, and NATURE databases. Data extraction and quality evaluation were done by Comprehensive Meta-Analysis, V3. Results: A total of 21 studies were included. The results showed that the combined physical and cognitive interventions produced significantly larger gains in executive functions, compared to the control group (standardized mean difference (SMD) = 0.26, 95% confidence interval (CI) [0.14, 0.39], p < 0.01). Furthermore, the effects of the combined physical and cognitive interventions were moderated by the study quality, intervention length, and intervention frequency. No significant differences were found between the combined interventions and the physical intervention alone (SMD = 0.13, 95% CI [-0.07, 0.33], p > 0.05) or the cognitive intervention alone (SMD = 0.13, 95% CI [-0.05, 0.30], p > 0.05). Conclusions: The combined physical and cognitive interventions effectively delayed the decrease of executive functions in older adults and this effect was influenced by the length and frequency of the intervention as well as the research quality. However, the effect of the combined physical and cognitive interventions was not significantly better than that of each intervention alone.


Asunto(s)
Trastornos del Conocimiento/terapia , Cognición/fisiología , Función Ejecutiva/fisiología , Ejercicio Físico , Anciano , Anciano de 80 o más Años , Trastornos del Conocimiento/prevención & control , Terapia por Ejercicio , Femenino , Humanos , Masculino , Terapia Ocupacional , Ensayos Clínicos Controlados Aleatorios como Asunto
18.
J Hum Kinet ; 73: 267-278, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32774558

RESUMEN

This investigation examined the effects of a 12-week mini-basketball training program (MBTP) on physical fitness and social communication in preschool children with autism spectrum disorders (ASD). The study applied a quasi-experimental design. Fifty-nine preschool children aged 3-6 years with ASD were assigned to either a MBTP group (n = 30) or a control group (n = 29). Participants in the MBTP group received a scheduled mini-basketball training program (5 sessions per week, forty minutes per session) for twelve consecutive weeks, while the control group was instructed to maintain their daily activities. The physical fitness test and the parent-reported Social Responsiveness Scale Second Edition (SRS-2) test were performed before and after the intervention. Results indicated that the 12-week MBTP facilitated performance in the physical fitness test, particularly in speed-agility and muscular strength abilities. Additionally, children in the MBTP group demonstrated improvement in SRS-2 performance in social awareness, social cognition, social communication, and autistic mannerisms, whereas no such changes were found in the control group. It may be concluded that the 12-week MBTP could improve physical fitness and social communication in preschool children with ASD, and thus the use of physical exercise intervention as a therapeutic tool for preschoolers with ASD is recommended.

19.
Artículo en Inglés | MEDLINE | ID: mdl-32373599

RESUMEN

Alterations of scapular kinematics affect the whole kinematic chain, potentially leading to the impingement syndrome. This is crucial in overhead sports, where athletes perform frequent and quick upper limb actions. In this manuscript, we aimed to assess the extent to which fatigue alters scapulo-thoracic and scapulo-humeral ranges of motion (RoM), as well as scapulo-humeral movement onset during different upper limb actions. Twenty-four young healthy males aged 22 ± 2 years (height: 1.82 ± 0.06 m, body mass: 78.0 ± 7.8 kg) performed three movements (upper limb elevation, scapular-plane abduction, and intra-extra rotation) before and after an isokinetic fatigue protocol (upper limb intra/extra rotation, 32 repetitions at 120 degrees/s). Pre vs. post fatigue RoM of humeral elevation and rotation, scapular retraction/protraction, and rotation and tilt were computed. Humerus-scapula movement delay was also determined. Humerus elevation range reduced during intra/extra humerus rotation in fatigued conditions (p = 0.006). Scapular tilt RoM increased after the fatigue protocol (p = 0.063, large effect). Humerus-scapular movement onset delay reduced in fatigued conditions of about 80 ms (p < 0.001, large effect). In sum, fatigued intra/extra upper limb rotators altered the scapulohumeral rhythm, and joints RoM in movements outside the scapular plane. Rather, movements close to the scapular plane were less prone to fatigue-induced alterations.

20.
J Sport Rehabil ; 29(8): 1047-1052, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31593927

RESUMEN

OBJECTIVES: The aim of the study was to investigate supraspinatus tendon thickness, acromiohumeral distance (AHD), and stiffness/creep measures of the shoulder girdle in overhead asymptomatic athletes in muscle fatigue conditions. DESIGN: Observational, case series study. SETTING: Biomechanics and motion analysis lab. PARTICIPANTS: Twenty-four male overhead volleyball (n = 8), handball (n = 8), and tennis (n = 8) athletes. All subjects were without shoulder injury history. MAIN OUTCOME MEASURE: The subjects were tested for supraspinatus tendon thickness (in short and long axis), AHD using ultrasound scans and stiffness/creep of upper trapezius, infraspinatus, anterior and posterior deltoid, and pectoralis major using the myotonometer device before and immediately after a fatigue protocol. INTERVENTION: The fatigue protocol consisted of 3 sets of 32 maximum isokinetic concentric contractions performing shoulder internal and external rotation at isokinetic speed of 120°/s. RESULTS: A significant increase in supraspinatus tendon thickness (both in short and long axis) (P = .045 and P = .01, respectively) and a reduction in AHD (P = .01) were found after an isokinetic protocol. The stiffness increased significantly in upper trapezius (P ≤ .01), infraspinatus (P = .003), posterior deltoid (P = .047), and pectoralis major (P = .01), whereas the creep showed a significant decrement for upper trapezius (P = .001) and infraspinatus (P = .003). CONCLUSION: The present study has demonstrated the postexercise fatigue in overhead athletes. The increase of stiffness (reduction of muscle creep) and tendon thickness (simultaneous to the reduction of AHD) may indicate rotator cuff overloading as a primary intrinsic tendon pathology process.


Asunto(s)
Fatiga Muscular/fisiología , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/fisiología , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/fisiología , Ultrasonografía , Atletas , Voluntarios Sanos , Humanos , Masculino , Adulto Joven
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