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Training, athlete, performance

Paul J Tofari, Stuart J Cormack, Tammie R Ebert, A Scott Gardner, Justin G Kemp
Talent identification (TID) and talent development (TDE) programmes in track sprint cycling use ergometer- and track-based tests to select junior athletes and assess their development. The purpose of this study was to assess which tests are best at monitoring TID and TDE. Ten male participants (16.2 ± 1.1 year; 178.5 ± 6.0 cm and 73.6 ± 7.6 kg) were selected into the national TID squad based on initial testing. These tests consisted of two 6-s maximal sprints on a custom-built ergometer and 4 maximal track-based tests (2 rolling and 2 standing starts) using 2 gear ratios...
October 25, 2016: Journal of Sports Sciences
Pedro Passos, Duarte Araújo, Keith Davids
An evolutionary psycho-biological perspective on competitiveness dynamics is presented, focusing on continuous behavioral co-adaptations to constraints that arise in performance environments. We suggest that an athlete's behavioral dynamics are constrained by circumstances of competing for the availability of resources, which once obtained offer possibilities for performance success. This defines the influence of the athlete-environment relationship on competitiveness. Constraining factors in performance include proximity to target areas in team sports and the number of other competitors in a location...
2016: Frontiers in Psychology
Michael V Hull, Andrew R Jagim, Jonathan M Oliver, Mike Greenwood, Deanna R Busteed, Margaret T Jones
BACKGROUND: Limited research exists on the effect of a sports dietitian (SD) on athletes' dietary habits and nutrient periodization, which is the deliberate manipulation of macronutrient intake to match training goals. Further, the difference in dietary habits between men and women collegiate athletes has been understudied. A survey questionnaire examining dietary habits and practices was administered to athletes at two universities that employed a full time SD. Not all athletes used the SD as their primary source for nutritional guidance...
2016: Journal of the International Society of Sports Nutrition
Bernard X W Liew, Susan Morris, Justin W L Keogh, Brendyn Appleby, Kevin Netto
BACKGROUND: In recent years, athletes have ventured into ultra-endurance and adventure racing events, which tests their ability to race, navigate, and survive. These events often require race participants to carry some form of load, to bear equipment for navigation and survival purposes. Previous studies have reported specific alterations in biomechanics when running with load which potentially influence running performance and injury risk. We hypothesize that a biomechanically informed neuromuscular training program would optimize running mechanics during load carriage to a greater extent than a generic strength training program...
October 22, 2016: BMC Musculoskeletal Disorders
Walter H Reinhart
The hematocrit (Hct) determines the oxygen carrying capacity of blood, but also increases blood viscosity and thus flow resistance. From this dual role the concept of an optimum Hct for tissue oxygenation has been derived. Viscometric studies using the ratio Hct/blood viscosity at high shear rate showed an optimum Hct of 50-60% for red blood cell (RBC) suspensions in plasma. For the perfusion of an artificial microvascular network with 5-70μm channels the optimum Hct was 60-70% for high driving pressures. With lower shear rates or driving pressures the optimum Hct shifted towards lower values...
October 21, 2016: Clinical Hemorheology and Microcirculation
Brun Jean-Frédéric, Varlet-Marie Emmanuelle, Fédou Christine, Raynaud de Mauverger Eric
We investigated to what extent a prediction of the 'ideal' hematocrit based on individual hemorheological profile with an equation of viscosity is relevant in trained athletes, and how the agreement between theoretical and actual values is modified by changes in training volume and performance. Elite soccer players (national level: 18-32 yr, weight 61-83 kg, body mass index 20.9-25.8 kg/m2) were seen twice at one year interval. Hemorheologic parameters were measured with the MT90 viscometer and the Myrenne aggregometer the theoretical bell-shaped curve of hematocrit/viscosity ratio as a function of hematocrit was reconstructed with Quemada's equation using actual plasma viscosity and red cell rigidity to predict hematocrit/viscosity at various hematocrit levels...
October 15, 2016: Clinical Hemorheology and Microcirculation
Brun Jean-Frédéric, Varlet-Marie Emmanuelle, Raynaud de Mauverger Eric
The hemorheological theory of optimal hematocrit suggests that the best value of hematocrit (hct) should be that which results in the highest value of the hematocrit/viscosity (h/η) ratio. Trained athletes compared to sedentary subjects have a lower hct, but a higher h/η, and endurance training reduces the discrepancy between the actual hct and the ⪡ideal⪢ hct that can be predicted with a theoretical curve of h/ηvs hct constructed with Quemada's model. In this study we investigated what becomes this homeostasis of h/η and hct during acute exercise in 19 athletes performing a 25 min exercise test...
October 17, 2016: Clinical Hemorheology and Microcirculation
Michael E Holmstrup, Brock T Jensen, William S Evans, Emily C Marshall
The kettlebell swing (KBS), emphasizing cyclical, explosive hip extension in the horizontal plane, aligns with movement- and velocity-specificity of sprinting. The present study examined the effect of an eight-week KBS intervention on sprinting in recreationally-active females, in comparison to an eight-week intervention using the stiff-legged deadlift (SDL). Following a pre-testing session measuring 30 meter sprint and countermovement vertical jump performance, participants were divided evenly by sprint time into KBS (n=8) and SDL (n=10) cohorts...
2016: International Journal of Exercise Science
Wen-Chyuan Chen, Yi-Ming Chen, Chi-Chang Huang, Yen-Dun Tzeng
Dehydroepiandrosterone (DHEA), the most abundant sex steroid, is primarily secreted by the adrenal gland and a precursor hormone used by athletes for performance enhancement. Whole-body vibration (WBV) is a well-known light-resistance exercise by automatic adaptations to rapid and repeated oscillations from a vibrating platform, which is also a simple and convenient exercise for older adults. However, the potential effects of DHEA supplementation combined with WBV training on to body composition, exercise performance, and hormone regulation are currently unclear...
2016: International Journal of Medical Sciences
Rosario Scarfone, Antonio Ammendolia
BACKGROUND: The aim of this study was to investigate the physiological demands and technical-tactical performances of field players in Italian elite beach soccer team. METHODS: Three official matches of the Italian First Division beach soccer tournament were analyzed to evaluate the heart rate (HR) and time-motion analysis considering: standing, walking, jogging, running and sprinting, and technical-tactical aspects. Repeated-measures ANOVAs were used to determine the effects of time on the physiological measures and time motion analysis...
October 20, 2016: Journal of Sports Medicine and Physical Fitness
Yaira Barranco-Ruiz, Antonio Martínez-Amat, Cristina Casals, Jerónimo Aragón-Vela, Silvia Rosillo, Silvana N Gomes, Ana Rivas-García, Rafael Guisado, Jesús R Huertas
The effect of exercise-induced oxidative stress on health and aging is not clearly explained. This study examined the effects of habitual sport practice, age, and submaximal exercise on the blood markers of oxidative stress, muscle damage, and antioxidant response. Seventy-two healthy men were grouped by their habitual sport practice: inactive (<1.5 h/week), recreational (3-8 h/week), and trained athletes (>8 h/week), and further divided by age: young (18-25 years), adult (40-55 years), and senior (>55 years)...
October 20, 2016: Journal of Physiology and Biochemistry
Noortje H Rijken, Remko Soer, Ewold de Maar, Hilco Prins, Wouter B Teeuw, Jan Peuscher, Frits G J Oosterveld
The aim of this pilot study was to investigate the effects of an intervention consisting of mental coaching combined with either electro encephalogram (EEG) alpha power feedback or heart rate variability (HRV) feedback on HRV, EEG outcomes and self-reported factors related to stress, performance, recovery and sleep quality in elite athletes. A prospective pilot study was performed with two distinct cohorts. Soccer players were provided with four sessions of mental coaching combined with daily HRV biofeedback (Group A); track and field athletes were provided with four sessions of mental coaching in combination with daily neurofeedback (Group B)...
October 19, 2016: Applied Psychophysiology and Biofeedback
Cory W Baumann, Dongmin Kwak
PURPOSE: Echinacea is an herbal supplement used by endurance athletes for its performance boosting properties. It is thought that Echinacea improves the blood's oxygen carrying capacity by increasing production of erythropoietin (EPO), a glycoprotein that regulates red blood cell formation. Subsequently, these changes would lead to an overall improvement in maximal oxygen uptake (VO2max) and running economy (RE), two markers of aerobic fitness. The purpose of this review is to briefly discuss the physiological variables associated with distance running performance and how these variables are influenced by Echinacea supplementation...
September 2016: Journal of Exercise Nutrition & Biochemistry
Attila Oláh, Dalma Kellermayer, Csaba Mátyás, Balázs Tamás Németh, Árpád Lux, Lilla Szabó, Marianna Török, Mihály Ruppert, Anna Meltzer, Alex Ali Sayour, Kálmán Benke, István Hartyánszky, Béla Merkely, Tamás Radovits
PURPOSE: Long-term exercise training is associated with characteristic cardiac adaptation, termed athlete's heart. Our research group previously characterized in vivo left ventricular (LV) function of exercise-induced cardiac hypertrophy in detail in a rat model, however the effect of detraining on LV function is still unclear. We aimed at evaluating the reversibility of functional alterations of athlete's heart after detraining. METHODS: Rats (n=16) were divided into detrained exercised (DEx) and detrained control (DCo) groups...
October 14, 2016: Medicine and Science in Sports and Exercise
Shannon Jordan, Justin Karcher, Rebecca Rogers, Kathleen Kennedy, Anne Lawrence, Jenny Adams
PURPOSE: Updated cardiac rehabilitation (CR) and return-to-work guidelines from the American College of Sports Medicine (ACSM) now include specificity of training for industrial athletes (exercise training that involves the muscle groups, movements, and energy systems that these patients use during occupational tasks). However, many CR facilities do not apply this principle, relying instead on the traditional protocol that consists primarily of aerobic exercise. This study was conducted to measure the metabolic cost of typical farming tasks and to compare 2 methods of calculating training intensities...
October 14, 2016: Journal of Cardiopulmonary Rehabilitation and Prevention
James C Boyett, Gabrielle E W Giersch, Christopher J Womack, Michael J Saunders, Christine A Hughey, Hannah M Daley, Nicholas D Luden
This project was designed to assess the effects of time of day and training status on the benefits of caffeine supplementation for cycling performance. Twenty male subjects (Age, 25 years; Peak oxygen consumption, 57 mL·kg(-1)·min(-1)) were divided into tertiles based on training levels, with top and bottom tertiles designated as 'trained' (n = 7) and 'untrained' (n = 7). Subjects completed two familiarization trials and four experimental trials consisting of a computer-simulated 3-km cycling time trial (TT)...
October 14, 2016: Nutrients
L Maïmoun, F Paris, O Coste, C Sultan
Participation in recreational physical activity is widely acknowledged to provide significant health benefits. Conversely, intense training imposes several constraints, such as intermittent or chronic metabolic and psychogenic training stressors and maintenance of very low body fat to maximize performance. Adolescent and adult athletic women are therefore at risk of overtraining and/or poor dietary intake, which may have several consequences for endocrine function particularly on hypothalamic-pituitary-gonadal axis...
October 14, 2016: Gynécologie, Obstétrique & Fertilité
Paul Comfort, Robert Williams, Timothy J Suchomel, Jason P Lake
The aim of this study was to compare load-absorption force-time characteristics of the clean from the knee (CK), power clean from the knee (PCK) and clean pull from the knee (CPK). Ten collegiate athletes (age 27.5 ± 4.2 years; height 180.4 ± 6.7 cm; mass 84.4 ± 7.8 kg), performed three repetitions each of the CK, PCK and CPK with 90% of their 1RM power clean on a force platform. The CK load-absorption duration (0.95 ± 0.35 s) was significantly longer compared to the CPK (0.44 ± 0.15 s; p < 0.001, d = 2...
September 27, 2016: Journal of Strength and Conditioning Research
Debbie Van Biesen, Florentina Hettinga, Katina McCulloch, Yves C Vanlandewijck
PURPOSE: To understand how athletes invest their energy over a race, differences in pacing ability between athletes with and without intellectual impairment (II) were explored using a novel field test. METHODS: Well-trained runners (n=67) participated in this study, including 34 runners with II (age = 24.4 ± 4.5 years; IQ = 63.1 ± 7.7) and 33 runners without II (age = 31.4 ± 11.2 years). The ability to perform at a pre-planned submaximal pace was assessed. Two 400m running trials were performed on an athletics track, with an individually standardized velocity...
October 5, 2016: Medicine and Science in Sports and Exercise
Kyle R Barnes, Andrew E Kilding
Running economy (RE) is considered an important physiological measure for endurance athletes, especially distance runners. This review considers 1) how RE is defined and measured and 2) physiological and biomechanical factors that determine or influence RE. It is difficult to accurately ascertain what is good, average, and poor RE between athletes and studies due to variation in protocols, gas-analysis systems, and data averaging techniques. However, representative RE values for different caliber of male and female runners can be identified from existing literature with mostly clear delineations in oxygen uptake across a range of speeds in moderately and highly trained and elite runners...
December 2015: Sports Medicine—Open
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