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1.
Int J Mol Sci ; 25(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731803

RESUMO

This study explores the effects of normobaric hypoxia and intermittent hypoxic training (IHT) on the physiological condition of the cardiac muscle in swimmers. Hypoxia has been reported to elicit both beneficial and adverse changes in the cardiovascular system, but its impact on the myocardium during acute exercise and altitude/hypoxic training remains less understood. We aimed to determine how a single bout of intense interval exercise and a four-week period of high-intensity endurance training under normobaric hypoxia affect cardiac marker activity in swimmers. Sixteen young male swimmers were divided into two groups: one undergoing training in hypoxia and the other in normoxia. Cardiac markers, including troponin I and T (cTnI and cTnT), heart-type fatty acid-binding protein (H-FABP), creatine kinase-MB isoenzyme (CK-MB), and myoglobin (Mb), were analyzed to assess the myocardium's response. We found no significant differences in the physiological response of the cardiac muscle to intense physical exertion between hypoxia and normoxia. Four weeks of IHT did not alter the resting levels of cTnT, cTnI, and H-FABP, but it resulted in a noteworthy decrease in the resting concentration of CK-MB, suggesting enhanced cardiac muscle adaptation to exercise. In contrast, a reduction in resting Mb levels was observed in the control group training in normoxia. These findings suggest that IHT at moderate altitudes does not adversely affect cardiac muscle condition and may support cardiac muscle adaptation, affirming the safety and efficacy of IHT as a training method for athletes.


Assuntos
Atletas , Biomarcadores , Hipóxia , Humanos , Masculino , Hipóxia/metabolismo , Projetos Piloto , Natação/fisiologia , Adulto Jovem , Miocárdio/metabolismo , Mioglobina/metabolismo , Troponina I/metabolismo , Proteína 3 Ligante de Ácido Graxo/metabolismo , Adolescente , Proteínas de Ligação a Ácido Graxo/metabolismo , Resistência Física/fisiologia , Creatina Quinase Forma MB/sangue , Creatina Quinase Forma MB/metabolismo , Adaptação Fisiológica , Altitude
2.
J Vasc Surg ; 77(2): 588-598.e3, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36334847

RESUMO

OBJECTIVE: Endurance athletes are prone to develop flow limitations in iliac arteries (FLIA). Especially in cyclists and ice speed skaters, excessive hemodynamic loading coupled with hip hyperflexion may cause kinking in lengthened iliac arteries necessitating surgical correction. This study investigated the short-term (≤1.5 years) and long-term (≥5 years) satisfaction of operative shortening of the iliac artery in endurance athletes. METHODS: All patients who were diagnosed and operated for FLIA owing to lengthened and kinked iliac arteries between 1997 and 2015 in one center were analyzed. Short-term follow-up consisted of an incremental maximal cycling test, ankle-brachial index with flexed hips, echo-Doppler examination with peak systolic velocity measurements and contrast-enhanced magnetic resonance angiography before and 6 to 18 months after surgery. Both short- and long-term satisfaction were assessed using questionnaires. RESULTS: A total of 83 patients (90 operated legs; 96.7% males; median age of 34 years at the time of surgery; interquartile range [IQR], 29-47) were analyzed. In the short-term, 87.5% reported symptom reduction with an 86.4% overall satisfaction rate. Symptom-free cycling improved from 272 ± 84 W to 384 ± 101 W (P < .001), whereas the maximal workload increased from 419 ± 72 W to 428 ± 67 W (P = .01). The ankle-brachial index with flexed hips increased from 0.55 (IQR, 0.45-0.65) to 0.62 (IQR, 0.52-0.74; P = .008), and the peak systolic velocity measured with hips flexed decreased from 2.50 m/s (IQR, 1.77-3.13 m/s) to 1.57 m/s (IQR, 1.20-2.04 m/s; P < .001). After a median of 12 years (IQR, 9.0-15.4 years), symptoms were still decreased in 84.1% of patients with an 81.2% overall satisfaction rate (79.5% response rate). Three patients needed a reintervention (recurrent FLIA, n = 2; failure, n = 1). CONCLUSIONS: Operative shortening of a lengthened and kinked iliac artery causing FLIA is successful both in the short- and long-term.


Assuntos
Atletas , Artéria Ilíaca , Masculino , Humanos , Adulto , Feminino , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/cirurgia , Artéria Ilíaca/patologia , Angiografia por Ressonância Magnética , Perna (Membro)/irrigação sanguínea , Ciclismo
3.
J Vasc Surg ; 78(2): 514-524.e2, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37060932

RESUMO

OBJECTIVE: Endurance athletes such as cyclists may develop intermittent claudication owing to iliac artery endofibrosis after long-lasting extreme hemodynamic challenges. This study investigated short-term (<1.5 years) and long-term (>5 years) satisfaction and safety after a surgical endarterectomy and autologous patching. METHODS: Data of endurance athletes who underwent an endarterectomy for flow limitation of the iliac artery owing to endofibrosis between 1997 and 2015 in one center were studied. Maximal cycling exercise tests, ankle-brachial index with flexed hips, echo-Doppler examination (peak systolic velocity), and contrast-enhanced magnetic resonance angiography were performed before and 6 to 18 months after surgery. Short-term and long-term satisfaction were evaluated using questionnaires. Potential patch dilatation was assessed using echo-Doppler. RESULTS: Analysis of 68 patients (79 legs; 55.7% males, median age at the time of surgery, 34 years; interquartile range, 26-41 years) demonstrated that cycling workload at symptom onset improved from 226 ± 97 to 333 ± 101 (P < .001) Watts. Peak workload increased from 326 ± 111 to 352 ± 93 Watts (P < .001). Ankle-brachial index with flexed hips increased from 0.34 (interquartile range [IQR], 0.00-0.47) to 0.59 (IQR, 0.51-0.69; P < .001). Peak systolic velocity with extended and flexed hip decreased from 2.04 m·sec-1 (IQR, 1.52-2.56 m·3sec-1) to 1.25 m·sec-1 (IQR, 0.92-1.62 m·sec-1; P < .001) and 2.40 m·sec-1 (IQR, 1.81-2.81 m·sec-1) to 1.15 m·sec-1 (IQR, 0.97-1.60 m·sec-1; P < .001), respectively. Thirty-day major complication rate was 5.1% (hematoma requiring evacuation nLegs = 2, septic bleeding from deep infection nLegs = 1, and iliac occlusion requiring thrombectomy nLegs = 1). In the short term, 91.2% of patients reported symptom reduction with a 93.7% overall satisfaction rate. After a median of 11.1 years (IQR, 7.8-17.6 years), the overall satisfaction was 91.7%; 94.5% of patients reported persistent symptom reduction. Patch dilatation of >20 mm was observed in two patients. Linear mixed model analysis revealed no alarming patch dilatation in the long term. CONCLUSIONS: Endarterectomy with an autologous patch for intermittent claudication owing to iliac artery endofibrosis in endurance athletes shows high rates of patient satisfaction and symptom reduction in both the short and long term. The risk of surgical complications or patch dilatation is mild. A surgical intervention for flow limitation of the iliac artery owing to endofibrosis is safe and successful.


Assuntos
Artéria Ilíaca , Claudicação Intermitente , Masculino , Humanos , Adulto , Feminino , Claudicação Intermitente/diagnóstico por imagem , Claudicação Intermitente/etiologia , Claudicação Intermitente/cirurgia , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/cirurgia , Artéria Ilíaca/patologia , Fibrose , Atletas , Endarterectomia/efeitos adversos
4.
Exp Brain Res ; 241(2): 341-354, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36520191

RESUMO

Increased exercise loads, as observed in elite athletes, seem to modulate the subjective pain perception in healthy subjects. The combination of electroencephalography (EEG) and standardized noxious stimulation can contribute to an objective assessment of the somatosensory stimulus processing. We assessed the subjective pain ratings and the electroencephalogram (EEG)-based response after standardized noxious mechanical and thermal stimuli as well as during conditioned pain modulation (CPM) in 26 elite endurance athletes and compared them to 26 recreationally active controls. Elite endurance athletes had consistently stronger somatosensory responses in the EEG to both mechanical and thermal noxious stimuli than the control group. We observed no significant group differences in the subjective pain ratings, which may have been influenced by our statistics and choice of stimuli. The CPM testing revealed that our conditioning stimulus modulated the subjective pain perception only in the control group, whereas the EEG indicated a modulatory effect of the conditioning stimulus on the spectral response only in the athletes group. We conclude that a higher activation in the cortical regions that process nociceptive information may either be an indicator for central sensitization or an altered stimulus salience in the elite endurance athletes' group. Our findings from our CPM testing were limited by our methodology. Further longitudinal studies are needed to examine if exercise-induced changes in the somatosensory system might have a critical impact on the long-term health of athletes.


Assuntos
Nociceptividade , Limiar da Dor , Humanos , Limiar da Dor/fisiologia , Medição da Dor/métodos , Dor , Atletas , Eletroencefalografia
5.
Scand J Med Sci Sports ; 33(4): 407-419, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36404133

RESUMO

INTRODUCTION: Accurate determination of total daily energy expenditure (TDEE) in athletes is important for optimal performance and injury prevention, but current approaches are insufficiently accurate. We therefore developed an approach to determine TDEE in professional cyclists based on power data, basal metabolic rate (BMR), and a non-exercise physical activity level (PAL) value, and compared energy expenditure (EE) between multi-day and single-day races. METHODS: Twenty-one male professional cyclists participated. We measured: (1) BMR, (2) the relationship between power output and EE during an incremental cycling test, which was used to determine EE during exercise (EEE ), and (3) TDEE using doubly labeled water (DLW). A non-exercise PAL-value was obtained by subtracting EEE from TDEE and dividing this by BMR. RESULTS: Measured BMR was 7.9 ± 0.8 MJ/day, which was significantly higher than predicted by the Oxford equations. A new BMR equation for elite endurance athletes was therefore developed. Mean TDEE was 31.7 ± 2.8 and 27.3 ± 2.8 MJ/day during the Vuelta a España and Ardennes classics, while EEE was 17.4 ± 1.8 and 10.1 ± 1.4 MJ/day, respectively. Non-exercise PAL-values were 1.8 and 2.0 for the Vuelta and Ardennes classics, respectively, which is substantially higher than currently used generic PAL-values. CONCLUSION: We show that the proposed approach leads to a more accurate estimation of non-exercise EE than the use of a generic PAL-value in combination with BMR predictive equations developed for non-elite athletes, with the latter underestimating non-exercise EE by ~28%. The proposed approach may therefore improve nutritional strategies in professional cyclists.


Assuntos
Metabolismo Energético , Água , Humanos , Masculino , Metabolismo Basal , Exercício Físico
6.
Eat Weight Disord ; 28(1): 101, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38070009

RESUMO

PURPOSE: Orthorexia nervosa involves restricting diet based on quality rather than quantity. Although orthorexia is well reported in many at-risk populations, limited data addresses its presence in individuals with eating disorder history (EDs) or athletes. We aimed to identify the presence and potential drivers of orthorexia in adults with EDs and endurance athletes, compared to control subjects. METHODS: Participants ≥ 18y included: people with a diagnosed eating disorder (ED as per DSM-5); endurance athletes (training/competing ≥ 5 h/week); or control subjects. Participants (n = 197) completed an online survey assessing orthorexia (eating habits questionnaire, EHQ), eating motivations (TEMS-B) and compulsive exercise (CET). RESULTS: ED had the highest orthorexia symptom severity (92.0 ± 3.02, n = 32), followed by athletes (76.2 ± 2.74, n = 54) and controls (71.0 ± 1.80, n = 111) (F (2) = 18.2, p < 0.001). A strong positive correlation existed between weight control motives and higher orthorexia symptom severity (r = 0.54, 95% CI [1.35, 2.36], p < 0.001), while a weak negative association existed between Hunger and Pleasure motives and higher orthorexia symptom severity (r = 0.23, 95% CI [- 2.24, - 0.34], p = 0.008; r = 0.26, 95% CI [- 2.11, - 0.47], p = 0.002, respectively). A moderate positive relationship was found between CET and orthorexia symptom severity (95% CI [1.52, 3.12], p < 0.001). CONCLUSION: Adults with ED history and endurance athletes have greater orthorexia symptom severity compared to control. Clinicians working with at-risk populations should screen patients and be aware of red-flags of orthorexic traits, desire to control weight, and compulsive exercise behavior. LEVEL OF EVIDENCE: III: Evidence obtained from cohort studies.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos , Ortorexia Nervosa , Adulto , Humanos , Estudos Transversais , Motivação , Atletas , Comportamento Alimentar , Inquéritos e Questionários , Comportamentos Relacionados com a Saúde
7.
J Vasc Surg ; 75(6): 1993-2001.e3, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35085748

RESUMO

OBJECTIVE: Endurance athletes can develop intermittent claudication due to sports-related flow limitations of the iliac artery (FLIA) caused by arterial kinking. In the present study, we investigated the short- and long-term efficacy of an operative release for iliac artery kinking. METHODS: Between 1996 and 2015, all patients with a diagnosis of FLIA due to iliac artery kinking without substantial arterial stenosis (<15%) or an excessive arterial length (vessel length to straight ratio, <1.25) who had undergone surgery were included. The short-term follow-up protocol consisted of cycling tests, the ankle brachial index with a flexed hip, and Doppler echography examinations to determine the peak systolic velocity before and 6 to 18 months after surgery. Additionally, the short- and long-term efficacy were evaluated using questionnaires. RESULTS: A total of 142 endurance athletes (155 legs; 88.4% male; median age, 26 years; interquartile range [IQR], 22-31 years) were available for analysis. In the short term, the symptoms had decreased in 83.9% of the patients, with an overall 80.3% satisfaction rate. Power during a maximal cycling test had improved from 420 W (IQR, 378-465 W) to 437 W (IQR, 392-485 W; P < .001). The symptom-free workload had increased from 300 W (IQR, 240-340 W) to 400 W (IQR, 330-448 W; P < .001). The postexercise ankle brachial index with a flexed hip had increased from 0.53 (IQR, 0.40-0.61) to 0.57 (IQR, 0.47-0.64; P = .002), and the peak systolic velocity with a flexed hip had decreased from 1.88 m/s (IQR, 1.45-2.50 m/s) to 1.52 m/s (IQR, 1.19-2.07 m/s; P < .001). Postoperative imaging studies revealed some degree kinking in 33.9%, mostly asymptomatic. The long-term results were evaluated after a median of 15.2 years (IQR, 10.9-19.5 years). The athletes had cycled an additional 125.500 km (IQR, 72.00-227.500 km), which was approximately equal to the 131.000 km (IQR, 98.250-220.000 km) cycled before the diagnosis of FLIA. On the long term, 63.9% of the athletes reported persistent reduction of complaints, with an overall 59.1% satisfaction rate. Eight patients had required reintervention, six because of treatment failure and two because of newly developed FLIA. CONCLUSIONS: Operative iliac artery release for sports-related functional kinking in the absence of stenosis or an excessive vessel length was effective for most athletes in the short and long term.


Assuntos
Artéria Ilíaca , Resistência Física , Adulto , Atletas , Constrição Patológica/complicações , Feminino , Humanos , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/cirurgia , Claudicação Intermitente/diagnóstico por imagem , Claudicação Intermitente/etiologia , Claudicação Intermitente/cirurgia , Masculino , Resultado do Tratamento , Adulto Jovem
8.
J Nutr ; 152(9): 2039-2047, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35661896

RESUMO

BACKGROUND: Declines in iron status are frequently reported in those who regularly engage in strenuous physical activity. A possible reason is increases in the iron regulatory hormone hepcidin, which functions to inhibit dietary iron absorption and can be induced by the inflammatory cytokine interleukin-6 (IL-6). OBJECTIVES: The current study aimed to determine the impact of a prolonged bout of running on hepcidin and dietary iron absorption in trained female and male runners. METHODS: Trained female and male collegiate cross country runners (n = 28, age: 19.7 ± 1.2 y, maximal oxygen uptake: 66.1 ± 6.1 mL $\cdot$ kg -1$\cdot$ min-2, serum ferritin: 21.9 ± 13.3 ng/mL) performed a prolonged run (98.8 ± 14.7 min, 21.2 ± 3.8 km, 4.7 ± 0.3 min/km) during a team practice. Participants consumed a stable iron isotope with a standardized meal 2 h postrun and blood was collected 1 h later. The protocol was repeated 2 wk later except participants abstained from exercise (rest). RBCs were collected 15 d after exercise and rest to determine isotope enrichment. Differences between exercise and rest were assessed by paired t tests and Wilcoxon matched-pairs signed rank tests. Data are means ± SDs. RESULTS: Plasma hepcidin increased 51% after exercise (45.8 ± 34.4 ng/mL) compared with rest (30.3 ± 27.2 ng/mL, P = 0.0010). Fractional iron absorption was reduced by 36% after exercise (11.8 ± 14.6 %) compared with rest (18.5 ± 14.4 %, P = 0.025). Plasma IL-6 was greater after exercise (0.660 ± 0.354 pg/mL) than after rest (0.457 ± 0.212 pg/mL, P < 0.0001). Exploratory analyses revealed that the increase in hepcidin with exercise may be driven by a response in males but not females. CONCLUSIONS: A prolonged bout of running increases hepcidin and decreases dietary iron absorption compared with rest in trained runners with low iron stores. The current study supports that IL-6 contributes to the increase in hepcidin with prolonged physical activity, although future studies should explore potential sex differences in the hepcidin response.This trial was registered at Clinicaltrials.gov as NCT04079322.


Assuntos
Hepcidinas , Corrida , Adolescente , Adulto , Feminino , Humanos , Interleucina-6 , Ferro , Ferro da Dieta , Masculino , Corrida/fisiologia , Adulto Jovem
9.
Scand J Med Sci Sports ; 32(10): 1414-1429, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35839336

RESUMO

The aim of this systematic review and meta-analysis was to identify the genetic variants of (inter)national competing long-distance runners and road cyclists compared with controls. The Medline and Embase databases were searched until 15 November 2021. Eligible articles included genetic epidemiological studies published in English. A homogenous group of endurance athletes competing at (inter)national level and sedentary controls were included. Pooled odds ratios based on the genotype frequency with corresponding 95% confidence intervals (95%CI) were calculated using random effects models. Heterogeneity was addressed by Q-statistics, and I2 . Sources of heterogeneity were examined by meta-regression and risk of bias was assessed with the Clark Baudouin scale. This systematic review comprised of 43 studies including a total of 3938 athletes and 10 752 controls in the pooled analysis. Of the 42 identified genetic variants, 13 were investigated in independent studies. Significant associations were found for five polymorphisms. Pooled odds ratio [95%CI] favoring athletes compared with controls was 1.42 [1.12-1.81] for ACE II (I/D), 1.66 [1.26-2.19] for ACTN3 TT (rs1815739), 1.75 [1.34-2.29] for PPARGC1A GG (rs8192678), 2.23 [1.42-3.51] for AMPD1 CC (rs17602729), and 2.85 [1.27-6.39] for HFE GG + CG (rs1799945). Risk of bias was low in 25 (58%) and unclear in 18 (42%) articles. Heterogeneity of the results was low (0%-20%) except for HFE (71%), GNB3 (80%), and NOS3 (76%). (Inter)national competing runners and cyclists have a higher probability to carry specific genetic variants compared with controls. This study confirms that (inter)national competing endurance athletes constitute a unique genetic make-up, which likely contributes to their performance level.


Assuntos
Atletas , Polimorfismo Genético , Humanos , Actinina/genética , Genótipo , Razão de Chances , Corrida , Ciclismo
10.
Scand J Med Sci Sports ; 32(10): 1493-1501, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35959514

RESUMO

INTRODUCTION: Previous studies have shown variable within-subject hemoglobin mass (Hbmass ) responses to altitude training. We investigated whether Hbmass responses depend on individual variations in pre-altitude Hbmass during repeated altitude sojourns. METHODS: Nine elite endurance athletes carried out 3-5 altitude sojourns over 17 ± 10 months (mean ± 95% confidence interval), at an altitude of 1976 ± 62 m, for 21 ± 1 days, and a total hypoxic dose of 989 ± 46 km·h, with Hbmass assessed before and after each sojourn (carbon monoxide rebreathing). The individual mean baseline was calculated as the mean of all pre-altitude Hbmass values for an athlete, and it was investigated whether the percent deviation from the individual mean baseline affected the altitude-induced Hbmass response. RESULTS: On average, Hbmass increased by 3.4 ± 1.1% (p < 0.001) from pre- to post-altitude. The intra-individual changes in Hbmass were highly inconsistent (coefficient of variation, CV: 88%), and we found no relationship between Hbmass changes in successive altitude sojourns (r = 0.01; p = 0.735). However, the percent increase in Hbmass was highly correlated with the pre-altitude Hbmass , expressed as the percent deviation from the individual mean baseline (y = -0.7x + 3.4; r = 0.75; p < 0.001). Linear mixed-model analysis confirmed a -0.6 ± 0.2% smaller increase in Hbmass for each 1% higher pre-altitude Hbmass than the individual mean baseline (p < 0.001) after adjusting for the covariates hypoxic dose (p = 0.032) and the relative Hbmass (g·kg-1 body weight; p = 0.031). CONCLUSION: Individual variations in pre-altitude Hbmass significantly influence the athletes' Hbmass responses to repeated altitude sojourns, with a potentiated response after traveling to altitude with a low pre-altitude Hbmass .


Assuntos
Altitude , Hemoglobinas , Atletas , Hemoglobinas/análise , Humanos , Hipóxia
11.
Eur J Appl Physiol ; 122(2): 503-513, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34825937

RESUMO

PURPOSE: Low energy availability in males needs more original research to understand its health and performance consequences. The aim of the study was to induce low energy availability in previously healthy male endurance athletes by reducing energy availability by 25% for 14 consecutive days and measure any potential changes in performance, health, mental state or energy markers. METHODS: Energy availability was reduced in 12 trained, well-trained and elite endurance athletes by increasing energy expenditure and controlling energy intake. After intervention, health was assessed by blood draw, body composition was measured, energy markers by measuring resting energy expenditure, performance with three specific tests (measuring endurance, agility and explosive power) and two questionnaires were used for psychological assessment (the Three Factor Eating Questionnaire and Well-being questionnaire). RESULTS: Reduced energy availability (22.4 ± 6.3 kcal/kg FFM/day) caused significantly lower haemoglobin values (t(12) = 2.652, p = 0.022), there was a tendency for lower iron and IGF-1 (p = 0.066 and p = 0.077, respectively). Explosive power was reduced (t(12) = 4.570, p = 0.001), lactate metabolism was altered and athletes reported poorer well-being (t(12) = 2.385, p = 0.036). Cognitive restriction was correlated with energy availability (r = 0.528, p = 0.039). CONCLUSION: This is the first research providing direct evidence that suboptimal energy availability negatively impacts explosive power before hormonal changes occur in male endurance athletes. It is also the first to show direct association of low energy availability and higher cognitive restriction. We also observed worse well-being and lower haemoglobin values. 25% of energy availability reduction as not enough to elicit changes in resting energy expenditure.


Assuntos
Desempenho Atlético/fisiologia , Ingestão de Energia , Metabolismo Energético/fisiologia , Resistência Física/fisiologia , Adolescente , Adulto , Biomarcadores/sangue , Composição Corporal , Humanos , Masculino
12.
J Sports Sci ; 39(22): 2558-2566, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34269142

RESUMO

Bone stress injury (BSI) is prevalent in female distance runners. Menstrual disturbances are associated with impaired bone health in endurance athletes. This study aimed to investigate the association between menstrual function and BSI and explore whether plyometric training may protect against BSI in individuals with menstrual disturbances. Competitive female distance runners (n = 183) aged 18-40 years were surveyed for training habits, menstrual function, and BSI, during the previous 12 months. Oligo/amenorrhoea during the previous 12 months (<9 menses) was deemed to indicate menstrual disturbance; hormonal contraceptive users and those previously diagnosed with a pathology that impacted menstrual function were excluded. BSI incidence rate was 2.25 (p = 0.02, 95% CI: 1.14-4.41) times greater in oligo/amenorrhoeic than eumenorrhoeic runners. BSI incidence rate was similar in oligo/amenorrhoeic and eumenorrhoeic runners that did plyometric training, but 3.78 (p = 0.001, 95% CI: 1.68-8.5) times greater in oligo/amenorrhoeic versus eumenorrhoeic runners that did not. However, the effect of plyometrics was non-significant (menstrual function × plyometric training interaction, p = 0.06; main effect, p = 0.89). Conventional plyometric training may not reduce BSI incidence in female distance runners, but menstrual disturbances and prolonged periods of low energy availability should be avoided.


Assuntos
Exercício Pliométrico , Corrida , Amenorreia/epidemiologia , Densidade Óssea , Feminino , Humanos , Incidência , Distúrbios Menstruais/epidemiologia
13.
Int J Sport Nutr Exerc Metab ; 31(4): 314-320, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34030124

RESUMO

Gastrointestinal disturbances are one of the most common issues for endurance athletes during training and competition in the heat. The relationship between typical dietary intake or nutritional interventions and perturbations in or maintenance of gut integrity is unclear. Twelve well-trained male endurance athletes (peak oxygen consumption = 61.4 ± 7.0 ml·kg-1·min-1) completed two trials in a randomized order in 35 °C (heat) and 21 °C (thermoneutral) conditions and kept a detailed nutritional diary for eight consecutive days between the two trials. The treadmill running trials consisted of 15 min at 60% peak oxygen consumption, 15 min at 75% peak oxygen consumption, followed by 8 × 1-min high-intensity efforts. Venous blood samples were taken at the baseline, at the end of each of the three exercise stages, and 1 hr postexercise to measure gut integrity and the permeability biomarker concentration for intestinal fatty-acid-binding protein, lipopolysaccharide, and lipopolysaccharide-binding protein. The runners self-reported gut symptoms 1 hr postexercise and 3 days postexercise. The heat condition induced large (45-370%) increases in intestinal fatty-acid-binding protein, lipopolysaccharide-binding protein, and lipopolysaccharide concentrations compared with the baseline, but induced mild gastrointestinal symptoms. Carbohydrate and polyunsaturated fat intake 24 hr preexercise were associated with less lipopolysaccharide translocation. Protein, carbohydrate, total fat, and polyunsaturated fat intake (8 days) were positively associated with the percentage increase of intestinal fatty-acid-binding protein in both conditions (range of correlations, 95% confidence interval = .62-.93 [.02, .98]). Typical nutrition intake partly explained increases in biomarkers and the attenuation of symptoms induced by moderate- and high-intensity exercise under both heat and thermoneutral conditions.


Assuntos
Ingestão de Alimentos , Trato Gastrointestinal/fisiologia , Temperatura Alta , Esforço Físico/fisiologia , Corrida/fisiologia , Adulto , Biomarcadores/sangue , Intervalos de Confiança , Estudos Cross-Over , Registros de Dieta , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Ingestão de Energia , Proteínas de Ligação a Ácido Graxo/sangue , Ácidos Graxos Insaturados/administração & dosagem , Humanos , Lipopolissacarídeos/sangue , Masculino , Consumo de Oxigênio , Condicionamento Físico Humano/fisiologia , Resistência Física , Fenômenos Fisiológicos da Nutrição Esportiva , Fatores de Tempo
14.
Sensors (Basel) ; 20(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32110939

RESUMO

The aim of this study was to evaluate changes in electromyographic activity with the use of gradual compression stockings (GCSs) on middle-distance endurance athletes' performance, based on surface electromyography measurement techniques. Sixteen well-trained athletes were recruited (mean ± SD: age 33.4 ± 6.3 years, VO2max 63.7 ± 6.3 mL·kg-1·min-1, maximal aerobic speed 19.7 ± 1.5 km·h). The athletes were divided into two groups and were assigned in a randomized order to their respective groups according to their experience with the use of GCSs. Initially, a maximum oxygen consumption (VO2max) test was performed to standardize the athletes' running speeds for subsequent tests. Afterward, electromyographic activity, metabolic, and performance variables for each group were measured with surface electromyography. In addition, blood lactate concentration was measured, both with and without GCSs, during 10 min at 3% above VT2 (second ventilatory threshold), all of which were performed on the track. Next, surface electromyography activity was measured during a 1 km run at maximum speed. No significant changes were found in electromyography activity, metabolic and performance variables with GCSs use (p > 0.164) in any of the variables measured. Overall, there were no performance benefits when using compression garments against a control condition.


Assuntos
Atletas , Músculos/fisiologia , Corrida/fisiologia , Meias de Compressão , Adulto , Eletromiografia , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino
15.
Eat Weight Disord ; 25(6): 1573-1582, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31654288

RESUMO

PURPOSE: Examine the prevalence and potential relationships among food addiction (FA)-as measured by Yale Food Addiction Scale 2.0 (YFAS 2.0), eating disorders (ED)-as measured by Eating Disorder Diagnostic Scale (EDDS)-and exercise dependence (EXD)-as measured by Questionnaire to Diagnose Exercise Dependence in Endurance Sports (FESA), for the first time worldwide, in amateur endurance athletes. METHODS: A total of 1022 German-speaking endurance athletes (44% male, Ø 36 years, Ø BMI 23 kg/m2) replied to an online questionnaire consisting of demographics, related parameters, and the German versions of YFAS 2.0, EDDS, and FESA. RESULTS: Prevalence of FA, ED, and EXD was 6.2, 6.5, and 30.5%. The probability for FA increases with BMI, thoughts about food and EXD score, and decreases with age and when an ED is present. People with FA and people with ED vs. people with both, FA&ED, differed significantly in this cohort. Strong significant relationships were found between FA and EXD (X2 (1) = 15.117, p < 0.001, n = 1022). CONCLUSIONS: A considerable number of amateur endurance athletes may suffer from FA. The association between FA and EXD is stronger than between ED and EXD, indicating FA as a potentially more relevant subject-than ED-for prevention or therapy in people with EXD. Further studies are needed to investigate parameters and relationships between the possibly involved types of ED, FA, and EXD. LEVEL OF EVIDENCE: Level III, well-designed cohort analytic study.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos , Dependência de Alimentos , Atletas , Exercício Físico , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Feminino , Humanos , Masculino , Inquéritos e Questionários
16.
J Am Coll Nutr ; 38(8): 729-738, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31084516

RESUMO

Objective: Nitrate (NO3-)-rich beetroot juice (BR) is recognized as an ergogenic supplement that improves exercise tolerance during submaximal to maximal intensity exercise in recreational and competitive athletes. A recent study has investigated the effectiveness of BR on exercise performance during supramaximal intensity intermittent exercise (SIE) in Olympic-level track cyclists, but studies conducted in elite endurance athletes are scarce. The present study aimed to determine whether BR supplementation enhances the tolerance to SIE in elite endurance athletes.Methods: Eleven elite endurance athletes (age: 21.7 ± 3.7 years, maximal oxygen uptake [Formula: see text] 71.1 ± 5.2 mL·kg-1·min-1) performed an SIE test until exhaustion following either a 3-day BR supplementation (340 mg/d) or a placebo (PL) supplementation (<2.5 mg/d) in a randomized, single blind, placebo-controlled, and crossover study. The exercise test consisted of 15-second cycling exercise bouts at 170% of the maximal aerobic power interspersed with 30-second passive recovery periods. Gas exchange was measured during SIE tests as local muscle O2 delivery and extraction were assessed by near infrared spectroscopy.Results: The number of repetitions completed was not significantly different between BR (13.9 ± 4.0 reps) and PL conditions (14.2 ± 4.5 reps). BR supplementation did not affect oxygen uptake ([Formula: see text]) during SIE tests (BR: 3378.5 ± 681.8 mL·min-1, PL: 3466.1 ± 505.3 mL·min-1). No significant change in the areas under curves was found for local muscle total hemoglobin (BR: 6816.9 ± 1463.1 arbitrary units (a.u.), PL: 6771.5 ± 3004.5 a.u.) and deoxygenated hemoglobin (BR: 6619.7 ± 875.8 a.u., PL: 6332.7 ± 1336.8 a.u.) during time-matched work + recovery periods from SIE tests following BR supplementation.Conclusions: BR supplementation does not enhance the tolerance to SIE in elite endurance athletes and affects neither [Formula: see text] nor local muscle O2 delivery and extraction.


Assuntos
Beta vulgaris , Suplementos Nutricionais , Exercício Físico , Sucos de Frutas e Vegetais , Resistência Física , Adolescente , Adulto , Atletas , Estudos Cross-Over , Frequência Cardíaca/efeitos dos fármacos , Humanos , Nitratos/sangue , Troca Gasosa Pulmonar/efeitos dos fármacos , Adulto Jovem
17.
Eur J Appl Physiol ; 119(8): 1747-1756, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31102062

RESUMO

PURPOSE: Weight-bearing activities such as running have been shown to be osteogenic. However, investigations have also shown that running may lead to site-specific deficiencies in bone mineral density (BMD) as well as overall low BMD. The purpose of this investigation was to evaluate and compare the BMD of female and male collegiate cross-country runners with non-running controls. In addition, energy availability and disordered eating attitudes and behaviors were assessed. METHODS: BMD of 60 collegiate cross-country runners and 47 BMI and age-matched non-running controls were measured via DXA scans. Participants completed a Block 2014 Food Frequency Questionnaire and Eating Disorder Examination Questionnaire. RESULTS: Controlling for fat-free mass (FFM), male runners showed greater BMD at the femoral neck (0.934 ± 0.029 vs. 0.866 ± 0.028 g cm2, p < 0.05), total hip (1.119 ± 0.023 vs. 1.038 ± 0.021 g cm2, p < 0.05), and whole body (1.119 ± 0.023 vs. 1.038 ± 0.021 g cm2, p < 0.05) than male controls. The female runners had greater whole-body BMD than female controls (1.143 ± 0.018 vs. 1.087 ± 0.022 g cm2, p < 0.05). Runners scored significantly higher than controls in dietary restraint (1.134 ± 1.24 vs. 0.451 ± 0.75, p < 0.05), male runners were significantly higher than male controls in eating concern (1.344 ± 1.08 vs. 0.113 ± 0.27, p < 0.05) and female runners were significantly higher than male runners in shape concern (1.056 ± 1.27 vs. 0.242 ± 0.31, p < 0.05). Forty-two percent of the male runners and 29% of female runners had an energy availability of less than 30 kcals kg-1FFM. CONCLUSION: It appears that distance running has beneficial effects on whole-body BMD and site-specific areas. Further research is warranted to further clarify the health effects of eating behaviors and EA of distance runners.


Assuntos
Densidade Óssea , Dieta , Metabolismo Energético , Corrida/fisiologia , Adulto , Feminino , Humanos , Masculino
18.
Int J Sport Nutr Exerc Metab ; 29(1): 32-38, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29757055

RESUMO

The legitimacy of urine specific gravity (USG) as a stand-alone measure to detect hydration status has recently been challenged. As an alternative to hydration status, the purpose of this study was to determine the diagnostic capability of using the traditional USG marker of >1.020 to detect insufficient recovery fluid consumption with consideration for moderate versus high sweat losses (2.00-2.99 or >3% body mass, respectively). Adequate recovery fluid intake was operationally defined as ≥100% beverage fluid intake plus food water from one or two meals and a snack. Runners (n = 59) provided 132 samples from five previous investigations in which USG was assessed 10-14 hr after 60-90 min runs in temperate-to-hot environments. Samples were collected after a meal (n = 58) and after waking (n = 74). When sweat losses exceeded 3% body mass (n = 60), the relationship between fluid replacement percentage and USG increased from r = -.55 to -.70. Correct diagnostic decision improved from 66.6 to 83.3%, and receiver operating characteristic area under the curve increased the diagnostic accuracy score from 0.76 to approaching excellent (0.86). Artifacts of significant prerun hyperhydration (eight of 15 samples has USG <1.005) may explain false positive diagnoses, while almost all (84%) cases of false positives were found when sweat losses were <3.0% of body mass. Evidence from this study suggests that euhydrated runners experiencing significant sweat losses who fail to reach adequate recovery fluid intake levels can be identified by USG irrespective of acute meal and fluid intake ∼12-hr postrun.

19.
Scand J Med Sci Sports ; 28(3): 881-892, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29117450

RESUMO

The purpose of this study was to investigate and assess the nutritional practices of open-water swimmers, during the preparation period and the competition, as well as their implications on performance and anthropometric parameters according to their age. Twenty-four (n = 24) men open-water swimmers, twelve young (26.3 ± 4.9 years) and twelve older athletes (45.8 ± 9.7 years), participated in this study. Nutritional behavior-energy intake consumption, and anthropometric characteristics were evaluated prior to the Toroneos Gulf crossing (26 km). In addition, nutritional intakes during the race and anthropometrics after the race were also evaluated. Significant differences between the two groups were found for Toroneos Gulf crossing performance, BMI, and all variables of body composition at the preparation period (P < .05). The results involving energy consumption, in both preparation period and during the race, displayed significant differences between the two groups, while both groups exhibited significantly negative energy balances. During the race, significant differences were found also for the energy expenditure, relative energy intake, negative energy balance, relative consumption of carbohydrates per hour, and relative protein intake (P < .05). In both groups, lower intakes than the recommended were observed for macronutrient-micronutrient elements at any time point. Significant correlations were found between selected variables of body composition, nutritional intakes during the preparation period and the competition, and athletes' performance. In summary, this study provides strong evidence about the malnutrition of ultra-endurance swimmers prior and during their competition, with potential dangers for their health and performance as certain deficiencies in both macro- and micronutrient contents are present.


Assuntos
Desempenho Atlético , Ingestão de Energia , Metabolismo Energético , Necessidades Nutricionais , Resistência Física , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto , Antropometria , Atletas , Composição Corporal , Dieta , Carboidratos da Dieta , Humanos , Masculino , Pessoa de Meia-Idade , Natação , Adulto Jovem
20.
Scand J Med Sci Sports ; 28(2): 400-406, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28581678

RESUMO

Titin provides a molecular blueprint for muscle sarcomere assembly, and sarcomere length can vary according to titin isoform expression. If variations in sarcomere length influence muscle fascicle length, this may provide an advantage for running performance. Thus, the aim of this study was to investigate whether the titin (TTN) rs10497520 polymorphism was associated with muscle fascicle length in recreationally active men (RA; n=137) and marathon personal best time in male marathon runners (MR; n=141). Fascicle length of the vastus lateralis was assessed in vivo using B-mode ultrasonography at 50% of muscle length in RA. All participants provided either a whole blood, saliva or buccal cell sample, from which DNA was isolated and genotyped using real-time polymerase chain reaction. Vastus lateralis fascicle length was 10.4% longer in CC homozygotes, those carrying two copies of the C-allele, than CT heterozygotes (P=.003) in RA. In the absence of any TT homozygotes, reflective of the low T-allele frequency within Caucasian populations, it is unclear whether fascicle length for this group would have been smaller still. No differences in genotype frequency between the RA and MR groups were observed (P=.500), although within the MR group, the T-allele carriers demonstrated marathon personal best times 2 minutes 25 seconds faster than CC homozygotes (P=.020). These results suggest that the T-allele at rs10497520 in the TTN gene is associated with shorter skeletal muscle fascicle length and conveys an advantage for marathon running performance in habitually trained men.


Assuntos
Desempenho Atlético , Conectina/genética , Resistência Física/genética , Corrida/fisiologia , Frequência do Gene , Genótipo , Humanos , Masculino , Músculo Quadríceps/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
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