164 research outputs found
Overtraining and exercise motivation: A research prospectus
The problems of exercise overtraining has recently become one of great interest to professionals in the field of human performance assessment. Quite obviously, the ultimate goal of the training process is to improve physical performance. However, excessive training can result in the opposite effect, that is, a performance decline and an impairment in the functional work capacity of the body. Research indicates that both psychological as well as physiological disturbances are quite common in overtrained individuals. For example, psychological changes include increased levels of depression, fatigue, and a lack of motivation. Similarly, impairment of the physiological function of the cardiovascular, metabolic, and endocrine systems also have been found. Some similarities may be found in the psychological and physiological states of crew members exposed to extended space flight and overtrained individuals. Therefore, the possibility exists that the crew members subjected to extended missions in space may develop overstressed or overtrained or both states during their flights. If such states do develop within the crew members, mission performance may be impaired. With these points as a background, the intent is to address potential research directions that NASA may consider viable and of a mutual interest to the researcher. A clear framework by which to begin discussion of research topics is needed; therefore, working definitions of overtraining and exercise motivation are presented. Subsequently, a proposed conceptional model of how exercise overtraining and motivation interact is presented. In support of the proposed model is a brief literature review of relevant areas. Potential research projects are presented and discussed
Clinical management of immunosuppression in sportsmen-women: recommendations for sports medicine physicians and physiotherapists
In sportsmen and sportswomen the Overtraining Syndrome (OTS) can be a physically debilitating medical condition that results in these men and women being totally compromised in their capacity to perform and compete athletically. Many physiological systems are affected by the process of overtraining and the OTS; but one system in particular, the immune, is highly susceptible to degradation resulting in a reduction in overall health and performance. The aim of this paper is twofold; 1) to review the evidence-based proactive steps and actions to greatly reduce the risk of development of an infection or a compromised immune system in sportsmen; and 2) to recommend the course of action for clinicians when they are dealing with an sportsmen and women displaying overt signs of an infection and, or inflammation. Based upon the evidence reviewed-presented herewithin, it can be concluded that it is essential for clinicians to take practical preventative and management steps – actions with sportsmen-women involved in intensive exercise training in order to help preserve a healthy and robust immune system
Characterization of the prolactin response to prolonged endurance exercise
This study characterized the blood prolactin responses to a prolonged endurance exercise bout in comparison to a resting, control period with no exercise. Six healthy exercise trained males completed both a 90 minute cycle exercise (70% VO2max) and a rest-control experimental session under standardized conditions. Blood samples were collected at – 15, 0 (exercise start), 15, 30, 45, 60, 75, 90 (exercise end), 105, and 120 minute time points in the exercise and rest-control sessions. Prolactin concentrations were analyzed using radioimmunoassay procedures and tested for significant changes with ANOVA analysis. In the exercise session, prolactin concentrations from 45 to 120 minutes were significantly greater than the 15 minute concentration before exercise (p < 0.01). Furthermore, the exercise concentrations at 45 to 120 minutes were also significantly greater than the concentrations observed at the comparable rest-control time points (p < 0.01; approximately 300% elevation). The frequent blood sampling protocol used in this study clearly portrays the magnitude, timeline, and extend of the prolactin response to prolonged endurance activity. The mechanism and role for the prolactin response was not the focus of this study, but relative to the latter, it is speculated the hormonal change could pertain to signaling energy usage-status within the body and, or prompting immune system activation
Comparison of the personality traits of male and female BASE jumpers
BASE jumping is an extreme adventure sport which consists of jumping from a fixed object with specially adapted parachutes. A few studies of the personality of BASE jumpers have been conducted, but little is known about how the women in this sport compare to the men. The purpose of this study is to compare the personality traits among a sample of men and women who are experienced BASE jumpers, as this provides an interesting and important opportunity to better understand the motivation for extreme sports. Eighty-three participants completed the Temperament and Character Inventory the day before the jump at the New River Gorge Bridge Day BASE Jumping event, West Virginia, United States. The sample included 64 men and 19 women. Results show that men and women BASE jumpers shared similar personality traits both in terms of temperament and character, except for the character trait of cooperativeness on which women scored higher than men. This suggests that the basic drive for participation in extreme sports is self-regulation of personal emotional drives and needs for self-actualization, rather than to oppose social pressure or cultural bias against female participation. These findings are discussed in relation with other studies conducted among extreme athletes and in terms of congruence between personality and activity
Hormony tarczycy a wzajemne relacje między stężeniem kortyzolu i prolaktyny: wpływ długotrwałego, wyczerpującego wysiłku fizycznego
Background: This study examined how prolonged, exhaustive exercise affects: (1) thyroid hormones, and (2) the interrelationship of
cortisol and prolactin responses to such exercise on thyroid hormones.
Material and methods: Male subjects performed a treadmill run at their individual ventilatory threshold until exhaustion. Blood samples
were taken before exercise at rest, baseline (BL), at exhaustion (EXH), 30-60-90-minutes into recovery (30 mR, 60 mR, 90 mR), and 24-hours
into recovery from exercise (24 hR). Blood was analyzed for free T3 (fT3), free T4 (fT4), thyroid-stimulating hormone (TSH), cortisol and
prolactin.
Results: ANOVA analysis revealed that at EXH all hormones were increased (p < 0.01) from BL levels. At 30 mR and 60 mR the thyroid
hormones had decreased and returned to BL levels; however, cortisol and prolactin remained significantly increased (p < 0.05). At 90 mR
all hormones were not different from BL levels. By 24 hR, cortisol, fT3 and TSH were decreased from BL (p < 0.05). Correlations revealed
EXH cortisol responses were related to the 24 hR TSH responses (rs = -0.69, p < 0.01). In addition, EXH cortisol and 24 hR fT3 responses
were related (rs = -0.51, p < 0.02). Furthermore, the EXH prolactin and TSH responses were related (rs = +0.56, p < 0.01), and the 30 mR
prolactin responses were related to the EXH TSH responses (rs = +0.43, p < 0.05).
Conclusions: Exhaustive exercise; (1) decreases select thyroid hormones by 24 hours into recovery, (2) cortisol responses are inversely
related to these thyroid reductions, and (3) prolactin responses (increases) are directly related to TSH changes.Wstęp: Celem niniejszego badania było określenie wpływu długotrwałego, wyczerpującego wysiłku fizycznego na: (1) stężenia wybranych
hormonów tarczycy i (2) współzależności między wydzielaniem kortyzolu i prolaktyny w odpowiedzi na ćwiczenia a stężeniami
hormonów tarczycy.
Materiał i metody: Zdrowe, wytrenowane osoby (n = 22) ćwiczyły na bieżni pochyłej ze zwykłą dla siebie intensywnością określona na
podstawie progu wentylacyjnego do momentu, kiedy poczuły zmęczenie (84,8 ± 3,8 min). Próbki krwi pobrano przed rozpoczęciem
ćwiczeń, kiedy badane osoby były wypoczęte (BL, baseline), a następnie w momencie, gdy nastąpiło wyczerpanie po wysiłku (EXH, exhanstion),
po 30-, 60-, i 90-minutowym odpoczynku i 24 godziny po zakończeniu ćwiczeń (24 hR). Oznaczono stężenia wolnej T3 (fT3), wolnej
T4 (fT4), hormonu tyreotropowego (TSH, thyroid stimulating hormone), prolaktyny i kortyzolu.
Wyniki: W analizie ANOVA dla powtarzalnych pomiarów wykazano, że stężenia wszystkich hormonów były podwyższone w fazie EXH
(p < 0,01) w stosunku do wartości wyjściowych (BL, baseline). Po 30- i 60-minutowym odpoczynku stężenia hormonów tarczycy zmniejszyły
się do wartości wyjściowych (p > 0,05); jednak stężenia kortyzolu i prolaktyny nadal były wyższe niż przed wysiłkiem (BL) (p < 0,05). Po
upływie 90 minut stężenia żadnego z hormonów nie różniły się istotnie (p > 0,05) od poziomu BL. Po 24 godzinach odpoczynku (24 hR)
stężenia kortyzolu, fT3 i TSH były niższe niż wartości BL (p < 0,05). Ocena korelacji wykazała zależność między stężeniem kortyzolu
w fazie zmęczenia po wysiłku a stężeniem TSH 24 po wysiłku (rs = -0,69, p < 0,01). Stężenie kortyzolu w fazie EXH i stężenie fT3 po
24 godzinach były związane w sposób statystycznie istotny (rs = -0,51, p < 0,02). Ponadto stwierdzono wzajemną zależność między
stężeniem prolaktyny i TSH w fazie EXH (rs = 0,56, p < 0,01), a stężenie prolaktyny po 30 minutach odpoczynku było związane ze
stężeniem TSH w fazie EXH (rs = 0,43, p < 0,05).
Wnioski: Wyniki uzyskane w niniejszym badaniu sugerują, że po wyczerpujących ćwiczeniach (1) następuje zmniejszenie wydzielania
wybranych hormonów tarczycy po 24 godzinach wypoczynku, a zmiany te są zależne od stężenia kortyzolu, (2) zwiększenie stężenia
prolaktyny spowodowane wysiłkiem jest proporcjonalne do wzrostu wydzielania TSH
Imuni sustav i prekomjeran trening kod športaša: kliničke implikacije
The primary objective of this review is to provide an overview of how overtraining and the overtraining syndrome (OTS) affect the immune system of athletes. A secondary objective is to provide sports medicine clinicians with guidance as to how best to prevent and/or treat some of the health consequences of overtraining and the OTS as related to the development of a compromised immune system associated with exercise training. The OTS is a physically debilitating condition that results in athletes being totally compromised in their capacity to perform and compete. Many physiological systems are affected by the process of overtraining and the OTS; but one system in particular, the immune, is highly susceptible to degradation resulting in a reduction in overall health and performance. Monitoring of an athlete’s exercise training load and other life stresses is critical to the determination of when their training regimen may be excessive, thereby increasing the risk of OTS developing. Taking steps to mitigate prolonged exposure to extreme stress (training + life or otherwise) in athletes as well as promoting a healthy immune system can significantly aid in the advancement of an athlete’s training regimen progression and ultimate physical performance and overall health. In this light, this review provides approaches to aid sports medicine clinicians in promoting a healthy immune system in athletes.Primarni cilj ovoga rada je dati pregled načina na koje prekomjeran trening i sindrom prekomjernog treninga utječu na imuni sustav športaša. Sekundarni cilj je pružiti kliničarima koji se bave športskom medicinom smjernice kako najučinkovitije spriječiti i/ili liječiti neke od zdravstvenih posljedica prekomjernog treninga i sindroma prekomjernog treninga u odnosu na razvoj poremećaja imunog sustava udruženih s treningom. Sindrom prekomjernog treninga je stanje onemoćalosti koje kod športaša potpuno onemogućava športske aktivnosti i natjecanje. Proces prekomjernog treninga i sindroma prekomjernog treninga utječe na mnoge fiziološke sustave, no jedan od tih sustava, tj. imuni sustav, osobito je osjetljiv na te utjecaje, što dovodi do poremećaja općeg zdravstvenog stanja i smanjene sposobnosti za športske aktivnosti. Ključno je pratiti opterećenje treningom i drugim životnim stresnim situacijama kod pojedinog športaša kako bi se utvrdilo kad je režim treniranja možda pretjeran pa postoji opasnost od razvoja sindroma prekomjernog treninga. Poduzimanjem mjera za ublažavanje izloženosti krajnjem stresu (trening + životne situacije ili drugo) kod športaša te podržavanjem zdravog imunog sustava može se značajno pomoći u promicanju progresivnog režima treniranja i krajnje fizičke učinkovitosti, kao i zdravlja općenito. U tom smislu ovaj pregled upućuje kako pomoći kliničarima koji se bave športskom medicinom u promicanju zdravog imunog sustava kod športaša
Human Performance Enhancement in Sports and Exercise: Nutritional Factors – Protein
Por años se ha dado un acalorado debate entre los nutricionistas deportivos sobre la pregunta “¿Los hombres y mujeres que son atletas necesitan más proteína en su dieta diaria que los individuos no-atletas?” Las investigaciones de las últimas décadas han dado evidencia de que la respuesta a esa pregunta es “si”. Los requerimientos de proteína tanto en los atletas de fuerza como en los de resistencia puede ser aproximadamente de 1.5 a 2.0 veces mayor que lo recomendado para un adulto (0.8 gramos de proteína alimenticia por quilogramo de masa corporal por día). La cantidad exacta dependerá de una variedad de factores, tales como el tipo y modalidad del ejercicio, la intensidad y duración del ejercicio, el sexo, si la persona es vegetariana, su edad y su salud. Este artículo trata las recomendaciones para los requisitos diarios de proteína de los atletas y aquellos factores que deben ser considerados por los atletas y sus entrenadores respecto al consumo de aminoácidos-proteína en la tentativa de perfeccionar el desempeño del ejercicio.UY-MoUC
Female physiology–endocrinology: education is lacking and innovation is needed!
Throughout their lifespans, women undergo unique endocrinological changes relative to their reproductive hormones. The influence of how the female sex steroid hormones have nonreproductive actions is a trending topic of great interest in the exercise–sports sciences, especially among women of reproductive age. Herein, we present several key points on our perspective for moving the study of this topic forward in the future. These are (a) encouraging researchers to pursue high-quality research on female physiology–endocrinology in the exercise–sports science setting, (b) the need for exercise–sports science educational curriculums at the university level to embrace the study of female physiology–endocrinology area, and (c) the need for innovation in the study of this topic. As such, we propose using research design models involving supraphysiological hormonal states in vivo, that is, pregnancy and in vitro fertilization treatment, to gain new insights on sex steroid hormonal actions in women. Herein, we provide the rationale for our recommendations as well as a brief physiological overview of these clinical states. We acknowledge, exercise sports sciences need more studies on women! But there is a need to “think outside the box” on this topic, and we encourage researchers to be unconventional, be bold, think creatively, and contemplate whether these supraphysiological hormonal states might give them insightful information on female physiology and ovarian sex steroid hormones actions
Human Performance Enhancement in Sports and Exercise: Nutritional Factors - “Carbohydrate Loading”
Se ha demostrado que el procedimiento dietético nutricional conocido como "carga de carbohidratos" aumenta sustancialmente los niveles de glucógeno muscular. El aumento del glucógeno muscular tiene un efecto ergogénico positivo en el rendimiento del ejercicio en eventos deportivos de más de 90 minutos de duración. Sin embargo, la eficacia del procedimiento de carga de carbohidratos es algo variable. Esta variabilidad puede atribuirse a factores que influyen en la capacidad del músculo para supercompensarse con el glucógeno. Este artículo discute los factores y aspectos del procedimiento que se suman a la variabilidad en un intento de mejorar el éxito de los deportistas (es decir, atletas) que intentan realizar el procedimiento de carga de carbohidratos y mejorar su rendimiento en el ejercicio.UY-MoUC
Cortisol and testosterone dynamics following exhaustive endurance exercise
Cortisol (C) and testosterone (T) are impacted significantly by prolonged endurance exercise with inverse responses. Increases in C are witnessed concurrently with decrements in T, possibly impacting recovery. This study was conducted to assess the dynamics of C and free T (fT) concentration and recovery time following an exhaustive endurance exercise session (EES)
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