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1.
Sports (Basel) ; 12(9)2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39330738

RESUMO

Multidisciplinary sports like triathlons require combining training for three different sports, and it is unclear how triathlon coaches manage this. During a 10-week period, we provided four age-group triathlon coaches with summary reports of the training completed by their athletes (n = 10) in the previous week. Coaches were then asked if the information provided to them was used to inform training prescription for the following week. The information provided to coaches included relative acute training load (rATL) and training stress scores (TSSs). Weekly fluctuations in rATL of >10% (spikes) were 83% (swim), 74% (bike) and 87% (run). Coaches adapted training loads for the upcoming week in 25% of all rATLs reported, and only 5% (swim), 33% (bike) and 9% (run) of the adjusted loads avoided spikes. Consequently, there were 22 single-discipline acute training load spikes vs. 14 spikes when combining all three disciplines. Only 1.5% of training was lost to injury, mostly after a large running-based training load spike (>30%). Coaches largely overlooked the information provided in the report when prescribing exercise for the following week, and when adjusted, it failed to bring weekly load variability <10%.

2.
Br J Sports Med ; 58(9): 470-476, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38331566

RESUMO

OBJECTIVE: To characterise the prevalence, incidence rate (IR) and burden of injuries in elite short-course triathletes over a 4-year training and competition period. METHODS: Fifty elite Australian triathletes were prospectively monitored for injury during four consecutive seasons (2018-2021). Injuries requiring medical attention were prospectively recorded and further subcategorised according to time loss. The IR and burden (injury IR×mean injury severity) were calculated per 365 athlete days, with sex differences in IR compared using IR ratios (IRR) from negative binomial regression models. RESULTS: Two hundred and sixty-six injuries were reported in 46 (92.0%) athletes, of which 67.3% resulted in time loss. The injury IR was 1.87 injuries per 365 athlete days (95% CI 1.70 to 2.80), and comparable between sexes (IRR 0.82, 95% CI 0.64 to 1.04, p=0.109). Most injuries (70.7%) were training related. The most frequently injured body sites were the ankle (15.8%), foot (12.4%) and lower leg (12.0%). Bone stress injuries (BSIs) were the most burdensome injury type with 31.38 days of time loss per 365 days (95% CI 24.42 to 38.34). Twenty athletes (40.0%) reported at least one bone stress injury (BSI) (range 0-3). The rate of BSIs in female athletes was three times greater compared with male athletes (IRR 2.99, 95% CI 1.26 to 7.07, p=0.013). CONCLUSION: Two-thirds of injuries reported in elite short-course triathletes resulted in time loss, with the majority occurring during training activities. Foot, ankle and other lower leg injuries had the highest incidence, with BSIs carrying the highest injury burden. The considerably higher rate of BSI observed in female athletes warrants consideration for future prevention strategies in female triathletes.


Assuntos
Traumatismos em Atletas , Natação , Humanos , Estudos Prospectivos , Feminino , Masculino , Traumatismos em Atletas/epidemiologia , Incidência , Prevalência , Adulto , Natação/lesões , Natação/estatística & dados numéricos , Austrália/epidemiologia , Corrida/lesões , Ciclismo/lesões , Adulto Jovem , Atletas/estatística & dados numéricos , Fraturas de Estresse/epidemiologia , Fatores Sexuais , Condicionamento Físico Humano/efeitos adversos
3.
Nurse Educ Today ; 136: 106133, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38387211

RESUMO

BACKGROUND: Higher education institutions offer in-country learning abroad programs to provide healthcare students with the opportunity to gain the intercultural and global competencies they need to work in a globally interconnected world. During the Covid-19 pandemic, institutions offered virtual learning abroad programs as an alternative to the in-country programs, however, little is known about whether they provide comparable benefits to students. OBJECTIVES: The purpose of this study was to investigate, and identify, the benefits gained by higher education healthcare students through their participation in a virtual learning abroad program. DESIGN/METHODS: This research implemented a qualitative approach, conducting semi-structured interviews with four higher education students enrolled in the final year of their healthcare studies. Data were analyzed using interpretative phenomenological analysis. RESULTS: The results revealed that virtual programs provide a range of benefits students can use in their future careers. They also provide students with a positive learning experience and an opportunity for personal growth. However, although the benefits students gain from virtual learning abroad programs are similar to those they gain from in-country programs, they are not identical. While virtual learning abroad programs are a viable alternative for in-country programs and offer many benefits, they fail to replicate the intercultural and global competencies that in-country programs offer to students. CONCLUSION: This study focusses on virtual learning abroad programs and whether the benefits healthcare students gain from them are comparable to the traditional in-country programs. Students gain personal and professional benefits from these programs without the risks and costs associated with international travel. However, the identified lack of increased global awareness has implications for how the benefits of virtual learning abroad programs should be promoted to students.


Assuntos
Educação a Distância , Bacharelado em Enfermagem , Estudantes de Enfermagem , Humanos , Bacharelado em Enfermagem/métodos , Pandemias , Estudantes , Atenção à Saúde
4.
J Sport Health Sci ; 13(2): 172-185, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36898525

RESUMO

BACKGROUND: Determining the incidence and prevalence of injury and illness in short-course triathletes would improve understanding of their etiologies and therefore assist in the development and implementation of prevention strategies. This study synthesizes the existing evidence on the incidence and prevalence of injury and illness and summarizes reported injury or illness etiology and risk factors affecting short-course triathletes. METHODS: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies reporting health problems (injury and illness) in triathletes (all sexes, ages, and experience levels) training and/or competing in short-course distances were included. Six electronic databases (Cochrane Central Register of Controlled Trials, MEDLINE, Embase, APA PsychINFO, Web of Science Core Collection, and SPORTDiscus) were searched. Risk of bias was independently assessed by 2 reviewers using the Newcastle-Ottawa Quality Assessment Scale. Two authors independently completed data extraction. RESULTS: The search yielded 7998 studies, with 42 studies eligible for inclusion. Twenty-three studies investigated injuries, 24 studies investigated illnesses, and 5 studies investigated both injuries and illnesses. The injury incidence rate ranged 15.7-24.3 per 1000 athlete exposures, and the illness incidence rate ranged 1.8-13.1 per 1000 athlete days. Injury and illness prevalence ranged between 2%-15% and 6%-84%, respectively. Most injuries reported occurred during running (45%-92%), and the most frequently reported illnesses affected the gastrointestinal (7%-70%), cardiovascular (14%-59%), and respiratory systems (5%-60%). CONCLUSION: The most frequently reported health problems in short-course triathletes were: overuse and lower limb injuries associated with running; gastrointestinal illnesses and altered cardiac function, primarily attributable to environmental factors; and respiratory illness mostly caused by infection.


Assuntos
Corrida , Humanos , Fatores de Risco , Corrida/lesões , Prevalência
5.
J Int Soc Sports Nutr ; 19(1): 505-528, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966021

RESUMO

BACKGROUND: To date, there is limited consensus on post-contest recovery recommendations for natural physique athletes. The available literature emphasizes the negative consequences of extreme dieting associated with physique contests, yet offers only speculative suggestions to facilitate physiological recovery post-contest. This scoping review evaluates evidence-based recommendations for recovery in post-physique contests. METHODS: The online search engines and databases Google Scholar, PubMed, and Scopus were searched systematically and 12 peer reviewed journal articles were included in the review. RESULTS: Six key factors were identified that directly impacted on physiological recovery post-contest: (1) body composition, (2) recovery dietary intake, (3) resting metabolic rate (RMR) restoration, (4) endocrine measures recovery, (5) menstrual cycle recovery, and (6) psychological aspects of recovery. CONCLUSIONS: Three dietary strategies have been proposed to facilitate physiological recovery post-contest while bearing in mind body composition and future athlete outcomes; (1) a gradual increase in energy intake to maintenance requirements, (2) ad libitum eating, (3) an immediate return to maintenance energy requirements. Future research is required to determine the timeline in which full physiological recovery occurs post-contest and which strategies best support athlete health and performance during post-contest recovery.


Assuntos
Atletas , Composição Corporal , Atletas/psicologia , Metabolismo Basal , Composição Corporal/fisiologia , Ingestão de Energia , Feminino , Humanos , Necessidades Nutricionais
6.
Nutrients ; 14(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35565896

RESUMO

We implemented a multi-pronged strategy (MAX) involving chronic (2 weeks high carbohydrate [CHO] diet + gut-training) and acute (CHO loading + 90 g·h−1 CHO during exercise) strategies to promote endogenous and exogenous CHO availability, compared with strategies reflecting lower ranges of current guidelines (CON) in two groups of athletes. Nineteen elite male race walkers (MAX: 9; CON:10) undertook a 26 km race-walking session before and after the respective interventions to investigate gastrointestinal function (absorption capacity), integrity (epithelial injury), and symptoms (GIS). We observed considerable individual variability in responses, resulting in a statistically significant (p < 0.001) yet likely clinically insignificant increase (Δ 736 pg·mL−1) in I-FABP after exercise across all trials, with no significant differences in breath H2 across exercise (p = 0.970). MAX was associated with increased GIS in the second half of the exercise, especially in upper GIS (p < 0.01). Eighteen highly trained male and female distance runners (MAX: 10; CON: 8) then completed a 35 km run (28 km steady-state + 7 km time-trial) supported by either a slightly modified MAX or CON strategy. Inter-individual variability was observed, without major differences in epithelial cell intestinal fatty acid binding protein (I-FABP) or GIS, due to exercise, trial, or group, despite the 3-fold increase in exercise CHO intake in MAX post-intervention. The tight-junction (claudin-3) response decreased in both groups from pre- to post-intervention. Groups achieved a similar performance improvement from pre- to post-intervention (CON = 39 s [95 CI 15−63 s]; MAX = 36 s [13−59 s]; p = 0.002). Although this suggests that further increases in CHO availability above current guidelines do not confer additional advantages, limitations in our study execution (e.g., confounding loss of BM in several individuals despite a live-in training camp environment and significant increases in aerobic capacity due to intensified training) may have masked small differences. Therefore, athletes should meet the minimum CHO guidelines for training and competition goals, noting that, with practice, increased CHO intake can be tolerated, and may contribute to performance outcomes.


Assuntos
Carboidratos da Dieta , Resistência Física , Atletas , Dieta , Feminino , Humanos , Masculino , Resistência Física/fisiologia , Caminhada/fisiologia
7.
Eur J Sport Sci ; 22(8): 1149-1155, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34379572

RESUMO

Race walkers must conform to a unique gait pattern with no visible loss of contact with the ground. However, how the gait pattern affects the race walking economy is unclear. We investigated the energy cost (amount of energy spent per distance unit) at different race walking velocities and over a 25 km hybrid walk. Twenty-one international-level male race walkers (V˙O2peak 63.8 ± 4.3 ml kg-1 min-1, age 31 ± 5 y, body mass 68.1 ± 7.0 kg) performed an incremental treadmill test consisting of 4 × 4 min submaximal stages with 1 km h-1 increments, and a 25 km submaximal hybrid walk (treadmill-overground) on separate days. Energy cost was measured continuously during the submaximal test and at km 0-1, 6-7, 12-13, 18-19, 23-24 of the 25 km hybrid walk. The CRW was similar across the four submaximal stages where half the athletes completed them at a higher (1 km h-1) absolute velocity (-0.01-0.15 ± ∼0.65); range of standardised differences ±90% CL, with a tendency for higher performing athletes to have a lower CRW when this was analysed during absolute race walking velocities of 12, 13 and 14 km-1 for the entire cohort (0.46-0.49 ± ∼0.67). There was no substantial change in CRW from the start to the end of the 25 km walk for the entire cohort (0.08 ± 2.2; standardised change ±90% CL). Elite race walkers are characterised by having a similar energy cost among athletes who perform at the same relative exercise intensity, and substantially higher energetics than counterpart elite endurance runners.


Assuntos
Consumo de Oxigênio , Caminhada , Adulto , Atletas , Teste de Esforço , Marcha , Humanos , Masculino
8.
J Sports Sci ; 40(5): 498-508, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34781841

RESUMO

Training task design with amateur female cricketers has typically comprised of deconstructed and monotonous approaches which may not maximise skill development. Clear guidelines to improve these practices in this cohort are lacking. The training environment should provide the same sources of information, decisions and variability as matches in order to prepare players for the match environment, which can be achieved through representative learning design (RLD). An RLD training intervention designed to promote skill development was performed over five weeks with two amateur female cricket teams to provide a framework for community coaches at the foundation stage of cricket. Skill development was recorded as changes in skilled actions for batting and bowling, with cognitions coded as themes for each skill during training. Six of ten batters and seven of eight bowlers exhibited increases in skill development ranging between 7-49%. Changes in batting and bowling behaviour improved substantially between moderately and extensively designed sessions. Batters' thoughts shifted from their own skill execution to objectives, while bowlers focused on their opponent's execution. Moderate to extensive RLD appears to promote skill development in amateur cricketers, making it a viable option for coach education and training design at the foundation level of cricket.


Assuntos
Esportes , Cognição , Estudos de Coortes , Feminino , Humanos , Aprendizagem
9.
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
10.
Int J Sports Physiol Perform ; 16(5): 744-747, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33571956

RESUMO

Negative or evenly paced racing strategies often lead to more favorable performance outcomes for endurance athletes. However, casual inspection of race split times and observational studies both indicate that elite triathletes competing in Olympic-distance triathlon typically implement a positive pacing strategy during the last of the 3 disciplines, the 10-km run. To address this apparent contradiction, the authors examined data from 14 International Triathlon Union elite races over 3 consecutive years involving a total of 725 male athletes. Analyses of race results confirm that triathletes typically implement a positive running pace strategy, running the first lap of the standard 4-lap circuit substantially faster than laps 2 (∼7%), 3 (∼9%), and 4 (∼12%). Interestingly, mean running pace in lap 1 had a substantially lower correlation with 10-km run time (r = .82) than both laps 2 and 3. Overall triathlon race performance (ranking) was best associated with run performance (r = .82) compared with the swim and cycle sections. Lower variability in race pace during the 10-km run was also reflective of more successful run times. Given that overall race outcome is mainly explained by the 10-km run performance, with top run performances associated with a more evenly paced strategy, triathletes (and their coaches) should reevaluate their pacing strategy during the run section.


Assuntos
Ciclismo , Natação , Atletas , Humanos , Masculino , Estado Nutricional , Fatores de Tempo
11.
Int J Sports Physiol Perform ; 16(5): 704-710, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33361496

RESUMO

PURPOSE: The risk of exercise-induced endotoxemia is increased in the heat and is primarily attributable to changes in gut permeability resulting in the translocation of lipopolysaccharides (LPS) into the circulation. The purpose of this study was to quantify the acute changes in gut permeability and LPS translocation during submaximal continuous and high-intensity interval exercise under heat stress. METHODS: A total of 12 well-trained male runners (age 37 [7] y, maximal oxygen uptake [VO2max] 61.0 [6.8] mL·min-1·kg-1) undertook 2 treadmill runs of 2 × 15-minutes at 60% and 75% VO2max and up to 8 × 1-minutes at 95% VO2max in HOT (34°C, 68% relative humidity) and COOL (18°C, 57% relative humidity) conditions. Venous blood samples were collected at the baseline, following each running intensity, and 1 hour postexercise. Blood samples were analyzed for markers of intestinal permeability (LPS, LPS binding protein, and intestinal fatty acid-binding protein). RESULTS: The increase in LPS binding protein following each exercise intensity in the HOT condition was 4% (5.3 µg·mL-1, 2.4-8.4; mean, 95% confidence interval, P < .001), 32% (4.6 µg·mL-1, 1.8-7.4; P = .002), and 30% (3.0 µg·mL-1, 0.03-5.9; P = .047) greater than in the COOL condition. LPS was 69% higher than baseline following running at 75% VO2max in the HOT condition (0.2 endotoxin units·mL-1, 0.1-0.4; P = .011). Intestinal fatty acid-binding protein increased 43% (2.1 ng·mL-1, 0.1-4.2; P = .04) 1 hour postexercise in HOT compared with the COOL condition. CONCLUSIONS: Small increases in LPS concentration during exercise in the heat and subsequent increases in intestinal fatty acid-binding protein and LPS binding protein indicate a capacity to tolerate acute, transient intestinal disturbance in well-trained endurance runners.


Assuntos
Endotoxemia/sangue , Exercício Físico/fisiologia , Transtornos de Estresse por Calor , Mucosa Intestinal/metabolismo , Consumo de Oxigênio , Corrida/fisiologia , Adulto , Teste de Esforço , Temperatura Alta , Humanos , Masculino , Esforço Físico
12.
Eur J Sport Sci ; 21(5): 695-704, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32316870

RESUMO

Applying heat training interventions in a team sports setting remains challenging. This study investigated the effects of integrating short-term, repeat sprint heat training with passive heat exposure on running performance and general conditioning in team sport players. Thirty male club-level Australian Football players were assigned randomly to: Passive + Active Heat (PAH; n = 10), Active Heat (AH; n = 10) or Control (CON; n = 10) to complete 6 × 40 min high-intensity cycling training sessions over 12 days in 35°C (PAH and AH) or 18°C (CON), 50% RH in parallel with mid-season sports-specific training and games. Players in PAH were exposed to 20 min pre-exercise passive heat. Physiological adaptation and running capacity were assessed via a treadmill submaximal heat stress test followed by a time-to-exhaustion run in 35°C, 50% RH. Running capacity increased by 26% ± 8% PAH (0.88, ±0.23; standardised mean, ± 90% confidence limits), 29% ± 12% AH (1.23, ±0.45) and 10% ± 11% CON (0.45, ±0.48) compared with baseline. Both PAH (0.52, ±0.42; standardised mean, ± 90% confidence limits) and AH (0.35, ±0.57) conditions yielded a greater improvement in running capacity than CON. Physiological and perceptual measures remained relatively unchanged between baseline and post-intervention heat stress tests, within and between conditions. When thermal adaptation is not a direct priority, short-term, repeat effort high-intensity cycling in hot conditions combined with sports-specific training can further enhance running performance in team sport players. Six heat exposures across 12-days should improve running performance while minimising lower limb load and cumulative fatigue for team sports players.


Assuntos
Desempenho Atlético , Temperatura Alta , Condicionamento Físico Humano , Corrida , Esportes de Equipe , Humanos , Masculino , Adulto Jovem , Adaptação Fisiológica , Desempenho Atlético/fisiologia , Intervalos de Confiança , Teste de Esforço , Tolerância ao Exercício/fisiologia , Condicionamento Físico Humano/métodos , Corrida/fisiologia , Termotolerância/fisiologia , Fatores de Tempo
13.
Nurse Educ Today ; 97: 104716, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341061

RESUMO

OBJECTIVES: An increasing number of higher education healthcare students from developed countries are undertaking short-term learning abroad programs in developing countries. However, sociocultural differences between the students and the communities could lead to unintended, possibly negative consequences for the community. The objective of this review was to explore what is known about the impact of learning abroad programs undertaken by healthcare students on the communities in the developing countries who host them. DESIGN: The six-step scoping review developed by Arksey and O'Malley (2005) provided a methodological framework for searching the literature and identifying records meeting the inclusion criteria. DATA SOURCES: A comprehensive range of databases were used to facilitate the literature search (including CINHAHL, EBSCO, ERIC, Google Scholar, MEDLINE, PsycINFO, Scopus and Web of Science). REVIEW METHODS: A two-stage review process was undertaken. Stage 1 reviewed articles on learning abroad undertaken in developing countries by higher education healthcare students. Stage 2 identified articles that reported the impact on the host community. Articles meeting the stage 2 criteria were further assessed for methodological quality using the Critical Review Form for Qualitative Studies. RESULTS: The stage 2 review revealed less than one quarter of the included articles (n = 36) reported on the impact of the learning abroad program on the host community and across these eight articles, there was a significant diversity in the methodological rigour and outcomes presented. CONCLUSIONS: This review identified that most of the published research on learning abroad in developing countries focusses almost exclusively on the impact the programs have on the students, with a paucity of research considering how they impact host communities. Our findings suggest the need to further extend and strengthen the research on the host communities in order to understand the impact higher education healthcare students have on the international communities who host them.


Assuntos
Países em Desenvolvimento , Aprendizagem , Atenção à Saúde , Humanos , Pesquisa Qualitativa
14.
Int J Sport Nutr Exerc Metab ; 31(1): 9-12, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33260142

RESUMO

The ingestion of quinine, a bitter tastant, improves short-term (30 s) cycling performance, but it is unclear whether this effect can be integrated into the last effort of a longer race. The purpose of this study was to determine whether midtrial quinine ingestion improves 3,000-m cycling time-trial (TT) performance. Following three familiarization TTs, 12 well-trained male cyclists (mean ± SD: mass = 76.6 ± 9.2 kg, maximal aerobic power = 390 ± 50 W, maximal oxygen uptake = 4.7 ± 0.6 L/min) performed four experimental 3,000-m TTs on consecutive days. This double-blind, crossover design study had four randomized and counterbalanced conditions: (a) Quinine 1 (25-ml solution, 2 mM of quinine); (b) Quinine 2, replicate of Quinine 1; (c) a 25-ml sweet-tasting no-carbohydrate solution (Placebo); and (d) 25 ml of water (Control) consumed at the 1,850-m point of the TT. The participants completed a series of perceptual scales at the start and completion of all TTs, and the power output was monitored continuously throughout all trials. The power output for the last 1,000 m for all four conditions was similar: mean ± SD: Quinine 1 = 360 ± 63 W, Quinine 2 = 367 ± 63 W, Placebo = 364 ± 64 W, and Control = 367 ± 58 W. There were also no differences in the 3,000-m TT power output between conditions. The small perceptual differences between trials at specific 150-m splits were not explained by quinine intake. Ingesting 2 mM of quinine during the last stage of a 3,000-m TT did not improve cycling performance.


Assuntos
Ciclismo/fisiologia , Substâncias para Melhoria do Desempenho/administração & dosagem , Resistência Física/efeitos dos fármacos , Quinina/administração & dosagem , Administração Oral , Estudos Cross-Over , Método Duplo-Cego , Humanos , Masculino , Percepção/fisiologia , Esforço Físico/fisiologia , Soluções
15.
Artigo em Inglês | MEDLINE | ID: mdl-33345062

RESUMO

Purpose: Heat training can be implemented to obtain performance improvements in hot and temperate environments. However, the effectiveness of these interventions for team sports during discrete periods of the season remains uncertain. Methods: We compared the effects of a short pre-season heat training intervention on fitness and thermal tolerance. In a counterbalanced crossover design, eleven state-level male football players undertook 6 × 60 min sessions in HEAT (35°C, 50% RH) and TEMP (18°C, 50% RH) conditions over 12 days. Running performance pre- and post-intervention was assessed via the Yo-Yo Interment Recovery Test Level 1 (YYIR1), and thermal adaptation using a submaximal (4 × 4 min @ 9-13 km·h-1) treadmill heat stress test in 35°C, 50% RH. Results: Running distance increased by 9, ±9% in HEAT (standardized mean, ±90% confidence limits) and 13, ±6% in TEMP, the difference in the mean change between conditions was unclear (0.24, ±0.64 standardized mean, ±90% confidence limits). Irrespective of training interventions, there was an order effect indicated by a substantial 476 ± 168 m increase in running distance between the first and final YYIR1 tests. There were trivial to small reductions in heart rate, blood lactate, RPE and thermal sensation after both interventions. Differences in mean core and skin temperature were unclear. Conclusions: Supplementary conditioning sessions in heat and temperate environments undertaken in addition to sports-specific field-based training were effective in enhancing player fitness during the pre-season. However, few clear differences between HEAT and TEMP conditions indicate conditioning in the heat appeared to offer no additional benefit to that of training in temperate conditions.

16.
Int J Sports Physiol Perform ; 15(9): 1309-1314, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32315983

RESUMO

PURPOSE: Traditional physiological testing and monitoring tools have restricted our ability to capture parameters that best relate to cycling performance under variable-intensity race demands. This study examined the validity of a 1-h variable cycling test (VCT) to discriminate between different-performance-level cyclists. METHODS: Ten male national- and 13 club-level cyclists (body mass, 67 [9] and 79 [6] kg; peak power output, 359 [43] and 362 [21] W, respectively) completed a VO2max test and two 1-h VCT protocols on 3 separate occasions. The VCT consisted of 10 × 6-min segments containing prescribed (3.5 W·kg-1) and open-ended phases. The open-ended phases consisted of 4 × 30-40 s of "recovery," 3 × 10 s at "hard" intensity, and 3 × 6-s "sprint" with a final 10-s "all-out" effort. RESULTS: Power output for the 6- and 10-s phases was moderately higher for the national- compared with club-level cyclists (mean [SD] 10.4 [2.0] vs 8.6 [1.6] W·kg-1, effect size; ±90% confidence limits = -0.87; ±0.65 and mean [SD] 7.5 [0.7] vs 6.2 [1.0] W·kg-1, effect size; ±90% confidence limits = -1.24; ±0.66, respectively). Power output for the final 10-s "all-out" sprint was 15.4 (1.5) for the national- versus 13.2 (1.9) W·kg-1 for club-level cyclists. CONCLUSION: The 1-h VCT can successfully differentiate repeat high-intensity effort performance between higher-caliber cyclists and their lower-performing counterparts.

17.
Sports (Basel) ; 7(5)2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31035719

RESUMO

Triathlon is characterized by the multidisciplinary nature of the sport where swimming, cycling, and running are completed sequentially in different events, such as the sprint, Olympic, long-distance, and Ironman formats. The large number of training sessions and overall volume undertaken by triathletes to improve fitness and performance can also increase the risk of injury, illness, or excessive fatigue. Short- and medium-term individualized training plans, periodization strategies, and work/rest balance are necessary to minimize interruptions to training due to injury, illness, or maladaptation. Even in the absence of health and wellbeing concerns, it is unclear whether cellular signals triggered by multiple training stimuli that drive training adaptations each day interfere with each other. Distribution of training intensity within and between different sessions is an important aspect of training. Both internal (perceived stress) and external loads (objective metrics) should be considered when monitoring training load. Incorporating strength training to complement the large body of endurance work in triathlon can help avoid overuse injuries. We explore emerging trends and strategies from the latest literature and evidence-based knowledge for improving training readiness and performance during competition in triathlon.

18.
Front Physiol ; 10: 100, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30837886

RESUMO

Bunch riding in closed circuit cycling courses and some track cycling events are often typified by highly variable power output and a maximal sprint to the finish. How criterium style race demands affect final sprint performance however, is unclear. We studied the effects of 1 h variable power cycling on a subsequent maximal 30 s sprint in the laboratory. Nine well-trained male cyclists/triathletes (O2peak 4.9 ± 0.4 L⋅min-1; mean ± SD) performed two 1 h cycling trials in a randomized order with either a constant (CON) or variable (VAR) power output matched for mean power output. The VAR protocol comprised intervals of varying intensities (40-135% of maximal aerobic power) and durations (10 to 90 s). A 30 s maximal sprint was performed before and immediately after each 1 h cycling trial. When compared with CON, there was a greater reduction in peak (-5.1 ± 6.1%; mean ± 90% confidence limits) and mean (-5.9 ± 5.2%) power output during the 30 s sprint after the 1 h VAR cycle. Variable power cycling, commonly encountered during criterium and triathlon races can impair an optimal final sprint, potentially compromising race performance. Athletes, coaches, and staff should evaluate training (to improve repeat sprint-ability) and race-day strategies (minimize power variability) to optimize the final sprint.

19.
Int J Sports Physiol Perform ; 14(6): 727­732, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30427232

RESUMO

Purpose: The authors investigated the potential benefit of ingesting 2 mM of quinine (bitter tastant) on a 3000-m cycling time-trial (TT) performance. Methods: Nine well-trained male cyclists (maximal aerobic power: 386 [38] W) performed a maximal incremental cycling ergometer test, three 3000-m familiarization TTs, and four 3000-m intervention TTs (∼4 min) on consecutive days. The 4 interventions were (1) 25 mL of placebo, (2) a 25-mL sweet solution, and (3) and (4) repeat 25 mL of 2-mM quinine solutions (Bitter1 and Bitter2), 30 s before each trial. Participants self-selected their gears and were only aware of distance covered. Results: Overall mean power output for the full 3000 m was similar for all 4 conditions: placebo, 348 (45) W; sweet, 355 (47) W; Bitter1, 354 (47) W; and Bitter2, 355 (48) W. However, quinine administration in Bitter1 and Bitter2 increased power output during the first kilometer by 15 ± 11 W and 21 ± 10 W (mean ± 90% confidence limits), respectively, over placebo, followed by a decay of 34 ± 32 W during Bitter1 and Bitter2 during the second kilometer. Bitter2 also induced a 11 ± 13-W increase during the first kilometer compared with the sweet condition. Conclusions: Ingesting 2 mM of quinine can improve cycling performance during the first one-third of a 3000-m TT and could be used for sporting events lasting ∼80 s to potentially improve overall performance.


Assuntos
Desempenho Atlético , Ciclismo , Substâncias para Melhoria do Desempenho/administração & dosagem , Quinina/administração & dosagem , Paladar , Adulto , Ingestão de Alimentos , Ergometria , Humanos , Masculino
20.
J Strength Cond Res ; 30(2): 533-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26154154

RESUMO

The purpose of this study was to evaluate vascular occlusion (OCC) and sequential intermittent pneumatic compression (SIPC) as recovery strategies after fatiguing resistance exercise. Twelve strength-trained male participants (age: 24.0 ± 6.3 years, height: 180.4 ± 9.7 cm, and weight: 84.8 ± 9.6 kg) participated in a randomized cross-over study. Participants performed a fatiguing resistance exercise bout consisting of 10 sets with 10 repetitions of back squats at 70% 1 repetition maximum with 3-minute rest between sets. Outcome measures of perceived recovery status, muscle soreness, concentric peak isokinetic torque of the quadriceps, squat jump (SJ) height, and countermovement jump (CMJ) height were taken before the fatiguing resistance exercise bout and repeated immediately post, 1 hour, and 24 hours later. Immediately after the postexercise measures, participants undertook 1 of the 3 recovery strategies: OCC, SIPC, and a passive control (CON). Concentric peak isokinetic torque of the quadriceps was decreased significantly immediately post and 1 hour after the fatiguing resistance exercise bout compared with baseline values (p ≤ 0.05). Mean SJ and CMJ jump height decreased significantly immediately post and 1 hour compared with baseline measures, but only the SJ was significantly decreased at 24 hours. There were no significant differences between conditions for any of the postexercise measures (p > 0.05). In conclusion, this study indicates that OCC and SIPC are not effective for attenuating muscle performance loss after a fatiguing resistance exercise bout relative to passive recovery.


Assuntos
Dispositivos de Compressão Pneumática Intermitente , Mialgia/prevenção & controle , Pressão , Músculo Quadríceps/fisiopatologia , Treinamento Resistido/efeitos adversos , Adulto , Estudos Cross-Over , Exercício Físico/fisiologia , Fadiga/fisiopatologia , Humanos , Masculino , Mialgia/fisiopatologia , Músculo Quadríceps/irrigação sanguínea , Treinamento Resistido/métodos , Torque , Resultado do Tratamento
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