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1.
Scand J Med Sci Sports ; 34(1): e14551, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38093477

RESUMO

PURPOSE: The purpose of the study was to investigate whether carbohydrate utilization is altered during exercise in overreached endurance athletes and examine the utility of continuous glucose monitors (CGM) to detect overreaching status. METHODS: Eleven endurance athletes (M:8, F:3) completed a 5-week training block consisting of 1 week of reduced training (PRE), 3 weeks of high-intensity overload training (POST), and 1 week of recovery training (REC). Participants completed a Lamberts and Lambert Submaximal Cycling Test (LSCT) and 5 km time-trial at PRE, POST, and REC time points, 15 min following the ingestion of a 50 g glucose beverage with glucose recorded each minute via CGM. RESULTS: Performance in the 5 km time-trial was reduced at POST (∆-7 ± 10 W, p = 0.04, η p 2 = 0.35) and improved at REC (∆12 ± 9 W from PRE, p = 0.01, η p 2 = 0.66), with reductions in peak lactate (∆-3.0 ± 2.0 mmol/L, p = 0.001, η p 2 = 0.71), peak HR (∆-6 ± 3 bpm, p < 0.001, η p 2 = 0.86), and Hooper-Mackinnon well-being scores (∆10 ± 5 a.u., p < 0.001, η p 2 = 0.79), indicating athletes were functionally overreached. The respiratory exchange ratio was suppressed at POST relative to REC during the 60% (POST: 0.80 ± 0.05, REC: 0.87 ± 0.05, p < 0.001, η p 2 = 0.74), and 80% (POST: 0.93 ± 0.05, REC: 1.00 ± 0.05, p = 0.003, η p 2 = 0.68) of HR-matched submaximal stages of the LSCT. CGM glucose was reduced during HR-matched submaximal exercise in the LSCT at POST (p = 0.047, η p 2 = 0.36), but not the 5 km time-trial (p = 0.07, η p 2 = 0.28) in overreached athletes. CONCLUSION: This preliminary investigation demonstrates a reduction in CGM-derived glucose and carbohydrate oxidation during submaximal exercise in overreached athletes. The use of CGM during submaximal exercise following standardized nutrition could be employed as a monitoring tool to detect overreaching in endurance athletes.


Assuntos
Exercício Físico , Resistência Física , Humanos , Glicemia , Glucose , Atletas
2.
Clin J Sport Med ; 33(1): 5-12, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36599359

RESUMO

OBJECTIVE: To apply the International Olympic Committee Sport Mental Health Assessment Tool 1 (SMHAT-1) to determine the prevalence of mental health symptoms in a cohort of university student athletes over an academic year. A secondary objective was to explore the internal consistency of the screening tools from the SMHAT-1. DESIGN: Cross-sectional design with 3 repeated measurements over an academic year. SETTING: A large university multisport program. PARTICIPANTS: Five hundred forty-two university-level student athletes from 17 sports. INTERVENTION: N/A. MAIN OUTCOME MEASURES: On 3 occasions, the participants completed the SMHAT-1, which consists of the Athlete Psychological Strain Questionnaire. If an athlete's score was above the threshold (≥17), the athlete completed step 2, consisting of (1) Generalized Anxiety Disorder-7; (2) Patient Health Questionnaire-9; (3) Athlete Sleep Screening Questionnaire; (4) Alcohol Use Disorders Identification Test Consumption; (5) Cutting Down, Annoyance by Criticism, Guilty Feeling, and Eye-openers Adapted to Include Drugs; and (6) Brief Eating Disorder in Athletes Questionnaire. Internal consistency of the SMHAT-1 was also measured. RESULTS: Participants reported mental health symptoms with prevalence of 24% to 40% for distress, 15% to 30% for anxiety, 19% to 26% for depression, 23% to 39% for sleep disturbance, 49% to 55% for alcohol misuse, 5% to 10% for substance use, and 72% to 83% for disordered eating. Female athletes were more likely to suffer psychological strain, depression, and sleep disturbance; male athletes were more likely to report substance use. CONCLUSIONS: The SMHAT-1 was feasible to implement with good internal consistency. University-level athletes suffer from a variety of mental health symptoms underscoring the necessity for team physicians to have the clinical competence to recognize and treat mental health symptoms.


Assuntos
Alcoolismo , Transtornos do Sono-Vigília , Masculino , Humanos , Feminino , Saúde Mental , Depressão/diagnóstico , Depressão/epidemiologia , Universidades , Estudos Transversais , Canadá/epidemiologia , Atletas/psicologia
3.
Clin J Sport Med ; 32(5): e485-e491, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36083335

RESUMO

OBJECTIVE: To characterize and compare the sport-specific cardiac structure of elite swimmers (SW), water polo players (WP), and artistic swimmers (AS). DESIGN: A cross-sectional assessment of elite aquatic athletes' hearts. SETTING: The athletes' village at the 2019 FINA World Championships. PARTICIPANTS: Ninety athletes from swimming (SW) (20 M/17 F), water polo (WP) (21 M/9 F), and artistic swimming (AS) (23 F). ASSESSMENT AND MAIN OUTCOME MEASURES: An echocardiographic assessment of cardiac structure was performed on noncompetition days. RESULTS: Male SW displayed primarily eccentric volume-driven remodeling, whereas male WP had a greater incidence of pressure-driven concentric geometry (SW = 5%, WP = 25%) with elevated relative wall-thickness (RWT) (SW = 0.35 ± 0.04, WP = 0.44 ± 0.08, P < 0.001). Female SW and WP hearts were similar with primarily eccentric-remodeling, but SW and WP had greater concentricity index than artistic swimmers (SW = 6.74 ± 1.45 g/(mL)2/3, WP = 6.80 ± 1.24 g/(mL)2/3, AS = 5.52 ± 1.08 g/(mL)2/3, P = 0.007). AS had normal geometry, but with increased posterior-wall specific RWT (SW = 0.32 ± 0.05, AS = 0.42 ± 0.11, P = 0.004) and greater left atrial area than SW (SW = 9.7 ± 0.9 cm2/m2, AS = 11.0 ± 1.1 cm2/m2, P = 0.003). All females had greater incidence of left ventricular (LV) posterior/septal wall-thickness ≥11 mm than typically reported (SW = 24%, WP = 11%, AS = 17%). CONCLUSIONS: Male athletes presented classic sport-specific differentiation, with SW demonstrating primarily volume-driven eccentric remodelling, and WP with greater concentric geometry indicative of pressure-driven remodeling. Female SW and WP did not display this divergence, likely because of sex-differences in adaptation. AS had unique LV-specific adaptations suggesting elevated pressure under low-volume conditions. The overall incidence of elevated wall-thickness in female athletes may point to an aquatic specific pressure-stress.


Assuntos
Atletas , Remodelação Ventricular , Estudos Transversais , Ecocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino
4.
Eur J Appl Physiol ; 121(9): 2635-2645, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34132871

RESUMO

PURPOSE: Factors such as prone body position, hydrostatic pressure, and intermittent breath-holding subject aquatic athletes to unique physical and environmental stressors during swimming exercise. The relationship between exposure to aquatic exercise and both arterial stiffness and wave reflection properties is not well-understood. This study assessed central artery stiffness and wave reflection properties in elite pool-swimmers (SW), long-distance open-water swimmers (OW), and water polo players (WP) to examine the relationship between these variables and aquatic exercise. METHODS: Athletes competing in SW, OW and WP events at the FINA World Championships were recruited. Carotid-femoral pulse wave velocity, and pulse wave analysis were used to quantify arterial stiffness, and central wave reflection properties. RESULTS: Athletes undertook differing amounts of weekly swimming distance in training according to their discipline (SW: 40.2 ± 21.1 km, OW: 59.7 ± 28.4 km, WP: 11.4 ± 6.3 km; all p < 0.05). Pulse wave velocity (Males [SW: 6.0 ± 0.6 m/s, OW: 6.5 ± 0.8 m/s, WP: 6.7 ± 0.9 m/s], Females [SW: 5.4 ± 0.6 m/s, OW: 5.3 ± 0.5 m/s, WP: 5.2 ± 0.8 m/s; p = 0.4]) was similar across disciplines for females but was greater in male WP compared to male SW (p = 0.005). Augmentation index (Males [SW: - 3.4 ± 11%, OW: - 9.6 ± 6.4%, WP: 1.7 ± 10.9%], Females [SW: 3.5 ± 13.5%, OW: - 13.2 ± 10.7%, WP: - 2.8 ± 10.7%]) was lower in male OW compared to WP (p = 0.03), and higher in female SW compared to OW (p = 0.002). Augmentation index normalized to a heart rate of 75 bpm was inversely related to weekly swim distance in training (r = - 0.27, p = 0.004). CONCLUSIONS: This study provides evidence that the central vasculature of elite aquatic athletes differs by discipline, and this is associated with training load.


Assuntos
Atletas , Natação , Rigidez Vascular/fisiologia , Adulto , Pressão Sanguínea/fisiologia , Feminino , Humanos , Masculino , Análise de Onda de Pulso , Fatores Sexuais , Adulto Jovem
7.
Can J Psychiatry ; 63(3): 182-196, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29513631

RESUMO

This paper has been substantially revised by the Canadian Psychiatric Association's Research Committee and approved for republication by the CPA's Board of Directors on May 3, 2017. The original policy paper1 was developed by the Scientific and Research Affairs Standing Committee and approved by the Board of Directors on November 10, 2008.


Assuntos
Guias como Assunto/normas , Meios de Comunicação de Massa/normas , Psiquiatria/normas , Sociedades Médicas/normas , Suicídio , Canadá , Humanos
8.
J Appl Physiol (1985) ; 136(3): 583-591, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38299223

RESUMO

Herein, we examine the human exercise response following cannabis inhalation, taking into consideration varied cannabinoid concentrations and different inhalation methods. A semirandomized crossover study design was used, with measures of perceived exertion and physiological responses to submaximal and maximal exercise. Participants (n = 14, 9 males 5 females) completed exercise after 1) smoking Δ-9-tetrahydrocannabinol (THC)-predominant cannabis (S-THC), 2) inhaling aerosol (vaporizing) from THC-predominant cannabis (V-THC), 3) inhaling aerosol from cannabidiol (CBD)-predominant cannabis (V-CBD), or 4) under control conditions. All exercise was performed on a cycle ergometer, with submaximal testing performed at 100 W followed by an evaluation of maximal exercise performance using an all-out 20-min time trial. Metabolism was characterized via the analysis of expired gases while subjective ratings of perceived exertion (RPE) were reported. During submaximal cycling, heart rate was higher during S-THC and V-THC compared with both control and V-CBD (all P < 0.02). During maximal exercise, V̇e was lower in V-THC compared with control, S-THC, and V-CBD (all P < 0.03), as was S-THC compared with control (P < 0.05). Both V̇o2 and RPE were similar between conditions during maximal exercise (both P > 0.1). Mean power output during the 20-min time trial was significantly lower in the S-THC and V-THC conditions compared with both control and V-CBD (all P < 0.04). Cannabis containing THC alters the physiological response to maximal and submaximal exercise, largely independent of the inhalation method. THC-containing cannabis negatively impacts vigorous exercise performance during a sustained 20-min effort, likely due to physiological and psychotropic effects. Inhalation of cannabis devoid of THC and primarily containing CBD has little physiological effect on the exercise response or performance.NEW & NOTEWORTHY Inhalation of cannabis containing THC alters physiological responses to both submaximal and maximal exercise and reduces mean power output during a 20-min time trial, regardless of whether it is inhaled as smoke or aerosol. In contrast, cannabis devoid of THC and predominantly containing CBD has no effect on physiological responses to exercise or performance.


Assuntos
Cannabis , Dronabinol , Feminino , Humanos , Masculino , Aerossóis , Canabidiol , Canabinoides , Cannabis/química , Estudos Cross-Over , Dronabinol/análise , Ciclismo
9.
Med Sci Sports Exerc ; 54(3): 507-516, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34690288

RESUMO

PURPOSE: Elite swimmers (Sw) have lower diastolic function compared with elite runners, possibly as an adaptation to the aquatic training environment. Water polo players (WP) and artistic swimmers (AS) are exposed to the same hydrostatic pressures as Sw, but they are subject to different training intensities, postures, and hemodynamic stressors. Our purpose was to compare resting and exercising cardiac function in elite Sw, WP, and AS, to characterize the influence of training for aquatic sport on left ventricular (LV) adaptation. METHODS: Ninety athletes (Sw, 20M/17F; WP, 21M/9F; AS, 23F) at the 2019 Fédération Internationale de Natation World Championships volunteered for resting and stress (3 min 30% maximal isometric handgrip) echocardiographic assessment of LV global function and mechanics. RESULTS: Male Sw displayed greater resting systolic and diastolic function compared with WP; however, both groups maintained stroke volume under high-pressure handgrip stress (Sw, ∆-4% ± 12%; WP, ∆-1% ± 13%, P = 0.11). There were no differences between female Sw and WP resting LV function, but Sw demonstrated greater function over AS. During isometric handgrip, all female sport athletes maintained stroke volume (Sw, ∆3% ± 16%; WP, ∆-10% ± 11%; AS, ∆-2% ± 14%, P = 0.46), but WP had improved apical rotation (∆1.7° ± 4.5°), which was reduced in AS (∆-3.1° ± 4.5°) and maintained in Sw (∆-0.5° ± 3.8°, P = 0.04). Unlike Sw and WP, AS displayed a unique maintenance of early filling velocity during handgrip exercise (Sw, ∆-3.5 ± 14.7 cm·s-1; WP, ∆-15.1 ± 10.8 cm·s-1; AS, ∆1.5 ± 15.3 cm·s-1, P = 0.02). CONCLUSIONS: Among male athletes, Sw display primarily volume-based functional adaptations distinct from the mixed volume-pressure adaptations of WP; however, both groups can maintain stroke volume with increased afterload. Female Sw and WP do not demonstrate sport-specific differences like males, perhaps owing to sex differences in adaptation, but have greater volume-based adaptations than AS. Lastly, AS display unique functional adaptations that may be driven by elevated pressures under low-volume conditions.


Assuntos
Atletas , Força da Mão/fisiologia , Natação/fisiologia , Função Ventricular Esquerda/fisiologia , Esportes Aquáticos/fisiologia , Adulto , Pressão Sanguínea/fisiologia , Ecocardiografia Doppler , Feminino , Humanos , Masculino , Volume Sistólico/fisiologia , Adulto Jovem
10.
J Appl Physiol (1985) ; 130(3): 660-670, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33444123

RESUMO

Cigarette smoking is among the most detrimental behaviors to cardiovascular health, resulting in arterial stiffening, endothelial dysfunction, and structural/functional alterations to the myocardium. Similar to cigarettes, cannabis is commonly smoked, and next to alcohol, is the most commonly used recreational substance in the world. Despite this, little is known about the long-term cardiovascular effects of smoking cannabis. This study explored the associations of cardiovascular structure and function with cannabis use in ostensibly healthy young participants (n = 35). Using echocardiography, carotid-femoral pulse wave velocity (cfPWV), and brachial flow-mediated dilation (FMD), we performed a cross-sectional assessment of cardiovascular function in cannabis users (n = 18) and controls (n = 17). There were no differences in cardiac morphology or traditional resting measures of systolic or diastolic function between cannabis users and controls (all P > 0.05), whereas cannabis users demonstrated reduced peak apical rotation compared with controls (cannabis users: 5.5 ± 3.8, controls: 9.6 ± 1.5; P = 0.02). Cannabis users had higher cfPWV compared with controls (cannabis users: 5.8 ± 0.6 m/s, controls: 5.3 ± 0.7 m/s; P = 0.05), whereas FMD was similar between cannabis users and controls (cannabis users: 8.3 ± 3.3%, controls: 6.8 ± 3.6%; P = 0.7). Young, healthy, and cannabis users demonstrate altered cardiac mechanics and greater aortic stiffness. Further studies should explore causal links between cannabis smoking and altered cardiovascular function.NEW & NOTEWORTHY Recreational cannabis is the most widely used substance in the world, other than alcohol. Yet, the effects of cannabis use on cardiovascular function and health are not well understood. Our cross-sectional data demonstrate that young, ostensibly healthy cannabis users have greater arterial stiffness and altered cardiac mechanics compared to nonusers. These findings suggest that cannabis users may be at greater risk of the development of future cardiovascular disease.


Assuntos
Cannabis , Rigidez Vascular , Artéria Braquial , Estudos Transversais , Humanos , Análise de Onda de Pulso , Fumantes , Fumar
11.
Sports Med ; 51(Suppl 1): 75-87, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34515970

RESUMO

Cannabis is widely used for both recreational and medicinal purposes on a global scale. There is accumulating interest in the use of cannabis and its constituents for athletic recovery, and in some instances, performance. Amidst speculation of potential beneficial applications, the effects of cannabis and its two most abundant constituents, delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), remain largely un-investigated. The purpose of this review is to critically evaluate the literature describing the effects of whole cannabis, THC, and CBD, on athletic performance and recovery. While investigations of whole cannabis and THC have generally shown either null or detrimental effects on exercise performance in strength and aerobic-type activities, studies of sufficient rigor and validity to conclusively declare ergogenic or ergolytic potential in athletes are lacking. The ability of cannabis and THC to perturb cardiovascular homeostasis warrants further investigation regarding mechanisms by which performance may be affected across different exercise modalities and energetic demands. In contrast to cannabis and THC, CBD has largely been scrutinized for its potential to aid in recovery. The beneficial effects of CBD on sleep quality, pain, and mild traumatic brain injury may be of particular interest to certain athletes. However, research in each of these respective areas has yet to be thoroughly investigated in athletic populations. Elucidating the effects of whole cannabis, THC, and CBD is pertinent for both researchers and practitioners given the widespread use of these products, and their potential to interact with athletes' performance and recovery.


Assuntos
Desempenho Atlético , Canabidiol , Cannabis , Canabidiol/farmacologia , Dronabinol/farmacologia , Humanos , Dor
12.
J Affect Disord ; 280(Pt A): 140-147, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33212405

RESUMO

BACKGROUND: Antidepressant efficacy is influenced by patient expectations and, in randomized controlled trials (RCTs), the probability of receiving a placebo. It is unclear whether tolerability demonstrates a similar pattern. This study aimed to determine whether study design influences adverse event (AE) rates in antidepressant trials for subjects receiving active treatment or placebo. METHODS: RCTs comparing one antidepressant to another antidepressant, placebo, or both in major depressive disorder (MDD) (1996-2018) were retrieved from Medline and PsycINFO. Clinicaltrials.gov was searched for unpublished trials. Of 1,997 studies screened, 77 trials were included. Studies were classified as drug-drug, drug-drug-placebo, or drug-placebo based on design and overall number of subjects experiencing any AE was recorded. Subgroup meta-analysis of proportions and meta-regression techniques were used to compare AE rates across study designs in patients receiving active antidepressant treatment and placebo. RESULTS: Among the actively treated, AE rates were lower in drug-drug trials (58.5%) compared to drug-drug-placebo (75.7%) and drug-placebo (76.4%) (the model reported coefficients for percent differences between AE rates of different study designs were B=17.0, p<0.001 and B=17.8, p<0.001, respectively). AE rates in patients receiving placebo were not different between study designs. LIMITATIONS: The present study is limited by the diverse range of study populations, variability in reporting of AEs, and specific antidepressants employed in the included trials. CONCLUSIONS: The inclusion of a placebo arm in the study design was unexpectedly associated with higher rates of AEs among patients receiving active medication in antidepressant trials. This observation has important implications for interpretation of trial tolerability findings.


Assuntos
Transtorno Depressivo Maior , Efeito Nocebo , Antidepressivos/efeitos adversos , Braço , Transtorno Depressivo Maior/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Int J Sports Physiol Perform ; 15(3): 354-360, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31188700

RESUMO

PURPOSE: Ischemic preconditioning (IPC) through purposeful circulatory occlusion may enhance exercise performance. The value of IPC for improving performance is controversial owing to challenges with employing effective placebo controls. This study examines the efficacy of IPC versus a deceptive sham protocol for improving performance to determine whether benefits of IPC are attributable to true physiological effects. It was hypothesized that IPC would favorably alter performance more than a sham treatment and that physiological responses to exercise would be affected only after IPC treatment. METHODS: In a randomized order, 16 participants performed incremental exercise to exhaustion on a cycle ergometer in control conditions and after sham and IPC treatments. Participants rated their belief as to the efficacy of each treatment compared with control. RESULTS: Time to exhaustion was greatest after IPC (control = 1331 [270] s, IPC = 1429 [300] s, sham = 1343 [255] s, P = .02), despite negative performance expectations after IPC and positive expectation after sham. Maximal aerobic power remained unchanged after both SHAM and IPC (control = 42.0 [5.2], IPC = 41.7 [5.5], sham = 41.6 [5.5] mL·kg-1·min-1, P = .7), as did submaximal lactate concentration (control = 8.9 [2.6], sham = 8.0 [1.9], IPC = 7.7 [2.1] mmol, P = .1) and oxygen uptake (control = 37.8 [4.8], sham = 37.5 [5.3], IPC = 37.5 [5.5] mL·kg-1·min-1, P = .6). CONCLUSIONS: IPC before cycling exercise provides an ergogenic benefit that is not attributable to a placebo effect from positive expectation and that was not explained by traditionally suggested mechanisms.

14.
J Affect Disord ; 267: 185-190, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32217218

RESUMO

BACKGROUND: Adverse events (AEs) are known to occur while patients are treated with placebos, part of the so-called nocebo effect. Yet evidence is limited regarding the likelihood that specific AEs occurring with antidepressant treatment are or are not due to nocebo effects. METHODS: This study identified 56 placebo-controlled, randomized controlled trials (RCTs) of antidepressant monotherapy for adults with major depressive disorder that reported AE rates in sufficient detail for comparison. Poisson regression analyses compared rates of AEs according to antidepressant class weighted by study population to determine which separated from placebo. A "nocebo index" was also calculated (with 0 defined as the lowest rate and 1 or higher indicating the same or greater rate of an AE in the placebo group). RESULTS: Numerous AEs did not differ statistically between antidepressant classes and placebo including worsening psychiatric symptoms, all forms of pain, weight gain and respiratory symptoms. Nevertheless, a number of AEs were significantly more common in antidepressants than placebos across multiple antidepressant classes. These were predominantly neurological, sexual and anticholinergic effects. Several AEs that separated statistically between antidepressants and placebos nevertheless had moderate nocebo indices (≥0.5). For example, dizziness in SSRIs separated significantly from placebo (OR 1.50, 95%CI 1.13-1.99) but had a nocebo index of 0.67. LIMITATIONS: This study relied on multiple RCTs with subtle design differences. CONCLUSIONS: This study identified several AEs that are likely the physiological result of antidepressants and many that likely represent nocebo effects. These results should inform clinical decision making and discussions with patients.


Assuntos
Transtorno Depressivo Maior , Adulto , Antidepressivos/efeitos adversos , Transtorno Depressivo Maior/tratamento farmacológico , Humanos , Efeito Nocebo , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos
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