Search results for "229"
showing 10 items of 1572 documents
Effects of work-interval duration and sport specificity on blood lactate concentration, heart rate and perceptual responses during high intensity int…
2018
The aim of this study was to examine the impacts on blood lactate concentration, measured heart rate and assessment of perceived exertion during split sessions of equal relative load, as also their relationship to the specific sport practised. Nineteen regional-level athletes (nine middle and long-distance runners (cyclic group) and ten field-sport team players (acyclic group)) performed four high-intensity interval training (HIIT) sessions with work-interval durations of 10 s, 50 s, 90 s and 130 s. The sessions were carried out at their usual training sites with a separation of at least 48 hours. Blood lactate concentration was measured at rest and 3 min after the completion of each protoc…
Controlled intermittent shortening contractions of a muscle-tendon complex: muscle fibre damage and effects on force transmission from a single head …
2005
This study was performed to examine effects of prolonged (3 h) intermittent shortening (amplitude 2 mm) contractions (muscles were excited maximally) of head III of rat extensor digitorum longus muscle (EDL III) on indices of muscle damage and on force transmission within the intact anterior crural compartment. Three hours after the EDL III exercise, muscle fibre damage, as assessed by immunohistochemical staining of structural proteins (i.e. dystrophin, desmin, titin, laminin-2), was found in EDL, tibialis anterior (TA) and extensor hallucis longus (EHL) muscles. The damaged muscle fibres were not uniformly distributed throughout the muscle cross-sections, but were located predominantly ne…
Low Energy Availability is Difficult to Assess But Outcomes Have Large Impact on Bone Injury Rates in Elite Distance Athletes
2018
We aimed to (a) report energy availability (EA), metabolic/reproductive function, bone mineral density, and injury/illness rates in national/world-class female and male distance athletes and (b) investigate the robustness of various diagnostic criteria from the Female Athlete Triad (Triad), Low Energy Availability in Females Questionnaire, and relative energy deficiency in sport (RED-S) tools to identify risks associated with low EA. Athletes were distinguished according to benchmarks of reproductive function (amenorrheic [n = 13] vs. eumenorrheic [n = 22], low [lowest quartile of reference range; n = 10] versus normal testosterone [n = 14]), and EA calculated from 7-day food and training d…
Effect of mountain ultramarathon distance competition on biochemical variables, respiratory and lower-limb fatigue
2020
The study aimed at assessing the acute physiological effects of running a 65-km vs a 107- km mountain ultramarathon. Nineteen athletes (15 males and 4 females) from the shorter race and forty three athletes (26 males and 17 females) from the longer race were enrolled. Body weight, respiratory and lower limb strength were assessed before and after the race. Blood samples were obtained before, after and 24-h post-race. Body weight loss did not differ between races. A decrease in squat jump height (p<0.01; d = 1.4), forced vital capacity (p<0.01; d = 0.5), forced expiratory volume in 1 s (p<0.01; d = 0.6), peak inspiratory flow (p<0.01; d = 0.6) and maximal inspiratory pressure (p<0.01; d = 0.…
Profiling children longitudinally: A three-year follow-up study of perceived and actual motor competence and physical fitness.
2020
Longitudinal designs enhance our understanding of children's development and its influence on movement behaviors and health. This three-year follow-up study aimed to develop profiles according to perceived and actual motor competence (MC) (locomotion, object control, and overall) and physical fitness in boys and girls longitudinally including children's temporal migrations among clusters in terms of profiling trends. A secondary aim was to compare physical activity participation and weight status at each time point according to these profiles. One hundred and four typically developing Spanish children (45.8% girls) between 4 and 9 years old at baseline participated in this study. Data were …
Effects of unstable shoes on trunk muscle activity in patients with chronic low back pain
2018
Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://www.sciencedirect.com/science/article/abs/pii/S0966636218307252?via%3Dihub En este artículo científico también participan los siguientes autores: María Dolores Arguisuelas, Julio Doménech-Fernández, Daniel Sánchez-Zuriaga, Juan José Amer-Cuenca, Javier Martínez-Gramage, Francisco Javier Montañez-Aguilera y Juan Francisco Lisón. Este es el pre-print del siguiente artículo: Salvador Coloma, P., Arguisuelas, MD., Doménech-Fernández, J., Sánchez-Zuriaga, D., Amer-Cuenca, JJ., Martínez-Gramage, J. et al. (2018). Effects of unstable shoes on trunk muscle activity in patients with chronic low back pai…
Effects of 12-Week Low or Moderate Dietary Acid Intake on Acid–Base Status and Kidney Function at Rest and during Submaximal Cycling
2018
Prolonged effects of dietary acid intake on acid–base status and kidney function have not yet been studied in an intervention study in healthy subjects. Dietary acid load can be estimated by calculating the potential renal acid load (PRAL) of foods. Effects of low-PRAL and moderate-PRAL diets on acid–base status and kidney function were investigated during a 12-week exercise training period. Healthy, 20–50-year-old men (n = 21) and women (n = 25) participated in the study and were randomly divided into low-PRAL and moderate-PRAL groups. Before (PRE), mid-phase (MID) and after the intervention (POST), the subjects participated in measurement sessions, where a 12-h urine sample and fasting bl…
Effects of Constant and Doublet Frequency Electrical Stimulation Patterns on Force Production of Knee Extensor Muscles
2016
International audience; This study compared knee extensors' neuromuscular fatigue in response to two 30-minute stimulation patterns: constant frequency train (CFT) and doublet frequency train (DFT). Fifteen men underwent two separate sessions corresponding to each pattern. Measurements included torque evoked by each contraction and maximal voluntary contractions (MVC) measured before and immediately after the stimulation sessions. In addition, activation level and torque evoked during doublets (Pd) and tetanic contractions at 80-Hz (P80) and 20-Hz (P20) were determined in six subjects. Results indicated greater mean torque during the DFT stimulation session as compared with CFT. But, no dif…
Priming the Motor Cortex With Anodal Transcranial Direct Current Stimulation Affects the Acute Inhibitory Corticospinal Responses to Strength Trainin…
2019
Frazer, AK, Howatson, G, Ahtiainen, JP, Avela, J, Rantalainen, T, and Kidgell, DJ. Priming the motor cortex with anodal transcranial direct current stimulation affects the acute inhibitory corticospinal responses to strength training. J Strength Cond Res 33(2): 307-317, 2019-Synaptic plasticity in the motor cortex (M1) is associated with strength training (ST) and can be modified by transcranial direct current stimulation (tDCS). The M1 responses to ST increase when anodal tDCS is applied during training due to gating. An additional approach to improve the M1 responses to ST, which has not been explored, is to use anodal tDCS to prime the M1 before a bout of ST. We examined the priming effe…
Beneficial Intervertebral Disc and Muscle Adaptations in High-Volume Road Cyclists.
2018
Purpose Cycling is widely practiced as a mode of transportation, a leisurely pursuit, and a competitive sport. Approximately half of cyclists experience low back pain. Yet, there has been limited study of spine tissue adaptations due to cycling.Methods To investigate potential risk factors for spinal pain, we compared 18 high-volume cyclists (>150 kmwk(-1) for 5 yr) to 18 height-matched nonsporting referents. Participants had no history of spinal pathology. Magnetic resonance imaging was used to quantify intervertebral disc (IVD) morphology and hydration, and psoas, erector spinae, quadratus lumborum, and multifidus muscle size and fat content. Endurance of trunk muscles (flexors and extens…