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1.
Med Sci Sports Exerc ; 56(3): 454-463, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38051143

RESUMO

PURPOSE: The purpose of this article was to analyze more than a century of cycling hour records (CHR) to examine the effects of sex, age, and altitude on cycling performance. Our hypotheses were that men's performance (distance) would exceed those of women by more than 10% but would decline at similar rates with aging and that altitude would have a small benefit, which might reach a maximum. METHODS: Data were cultivated from the Facebook World Hour Record Discussion Group's crowd-sourced database of more than 600-known-hour records and verified through extensive online research and/or personal communication. Regression and statistical modeling were produced using STATA v15.0. R2 values were used to ascertain model quality, with four distinct models being produced for comparisons. Alpha was set at 0.05 significance for all tests. RESULTS: R2 values ranged from 65% to 74.9%. Women's distances were 10.8% shorter ( P < 0.001) than those of men, but the difference was narrower than either the historical elite women's difference of 14.2% or the 2022 record difference of 13.3%. Age-related decline modeling indicates performance declines significantly past age 40 yr at a rate of 1.08% per year. Altitude had a significant ( P < 0.001) marginal improvement up to 1000 m before declining. The marginal benefits of altitude were small, but this is consistent with the finding benefits reach a maximum at a moderate altitude with "benefits" becoming ambiguous starting at ~1000 m. Technological advancement was estimated to be a small but significant ( P < 0.001) improvement of ~0.18% per year. CONCLUSIONS: Across decades of CHR data in well-trained endurance cyclists, men are only ~11% faster, and this difference remains stable until at least age 80 yr. CHR attempts greater than 500 m likely offer at best a small advantage. Despite small year-on-year improvements, the CHR has likely improved more than 10 km because of technological advancements.


Assuntos
Envelhecimento , Ciclismo , Masculino , Humanos , Feminino , Adulto , Idoso de 80 Anos ou mais , Modelos Estatísticos , Altitude , Tecnologia
2.
Sports (Basel) ; 9(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34678917

RESUMO

(1) Background: This report examines the unique demands of off-road triathlon (XT) by presenting physiological, field, and race data from a national champion off-road triathlete using several years of laboratory and field data to detail training and race intensity. (2) Methods: Laboratory and field data were collected when the athlete was at near peak fitness and included oxygen consumption (VO2), heart rate (HR), power output (W), and blood lactate (BLC) during cycling and running, while HR, cycling W, and running metrics were obtained from training and race data files over a period of seven years. Intensity was described using % HR max zones (Z) 1 < 75%, 2 = 75-87%, and Zone 3 > 87%, and W. An ordinary least squares analysis was used to model differences between event types. (3) Results: Weather conditions were not different across events. XT events had twice the elevation change (p < 0.01) and two-three times greater anaerobic work capacity (W') (p < 0.001) than road triathlon (ROAD), but similar HR intensity profiles (max, avg, and zones); both events are predominately performed at >Z2 or higher intensity. Championship XT events were longer (p < 0.01), with higher kJ expenditure (p < 0.001). Ordinary Least Squares (OLS) modelling suggested three variables were strongly related (R2 = 0.84; p < 0.0001) to cycling performance: event type (XT vs ROAD), total meters climbed, and total bike duration. Championship XT runs were slower than either regional (p < 0.05) or ROAD (p < 0.01) runs, but HR intensity profiles similar. OLS modelling indicates that slower running is linked to either greater total bike kJ expenditure (R2 = 0.57; p < 0.001), or total meters gained (R2 = 0.52; p < 0.001). Race simulation data support these findings but failed to produce meaningful differences in running. Conclusions: XT race demands are unique and mirror mountain bike (MTB) and trail running demands. XT athletes must be mindful of developing anaerobic fitness, technical ability, and aerobic fitness, all of which contribute to off-road cycling economy. It is unclear whether XT cycling affects subsequent running performance different from ROAD cycling.

3.
Int J Sports Phys Ther ; 14(4): 537-545, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31440406

RESUMO

BACKGROUND: Sports medicine professionals have instituted easy to use on field screening tests to determine physical readiness and identify athletes who may have increased injury risk. Currently there is little research on fundamental movement and dynamic balance abilities in golfers. PURPOSE: To examine differences in fundamental movement patterns and dynamic balance in varying competition levels in golfers. STUDY DESIGN: Cross-sectional Cohort. METHODS: The Functional Movement ScreenTM (FMS), and Y-Balance Test Upper Quarter and Lower Quarter (YBT-LQ/UQ) were performed on middle school (MS), high school (HS), college (COL), and professional (PRO) golfers. The FMSTM was assessed for individual tests and composite score. The YBT-LQ/UQ reaches were averaged normalized to limb length. Statistical analysis was completed with a series of Kruskall-Wallis tests with Dunn's post hoc for the FMS™ and YBT-LQ/UQ asymmetries, and a series of ANOVAs, with Tukey's post hoc for the YBT-LQ/UQ reaches (p<0.05). Effect Size Indices (ESI) were also calculated to determine clinical relevance. RESULTS: A total of 53 MS, 129 HS, 207 COL, and 29 PRO golfers were included in this study. Significant differences were observed between COL and HS in two FMS™ tests (push up; p=0.001), active straight leg raise; p=0.0019). PRO golfers YBT-LQ posteromedial reaches were greater than MS (p=0.0127, ESI = 4.3552). PRO YBT-UQ medial reaches were greater than COL (p<0.0001, ESI = 0.8915), HS (p<0.0001, ESI = 1.2640) and MS (p<0.001, ESI = 1.4218). PRO inferolateral (IL) and superoloateral (SL) reaches were greater [IL: COL (p=0.0427, ESI = 0.4413), HS (p=0.0002, ESI = 0.5851)], [SL: COL (p=0.0005, ESI = 0.5990), HS (p=0.0004, ESI = 0.6068)]. YBT-UQ composite scores were greater for PRO compared to COL (p<0.0001, ESI = 0.7657), HS (p<0.0001, ESI = 0.8161) and MS (p<0.0001, ESI = 1.085). CONCLUSIONS: Differences were observed in golfer's fundamental movement patterns in relationship to competition level. These data can be utilized to design personalized training programs that focus to improve movement quality. LEVEL OF EVIDENCE: 2b.

4.
Res Sports Med ; 27(2): 134-146, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30411978

RESUMO

Endurance performance is the result of optimal training targeting cardiovascular, metabolic, and peripheral muscular adaptations and is coupled to effective nutrition strategies via the use of macronutrient manipulations surrounding training and potential supplementation with ergogenic aids. It is important to note that training and nutrition may differ according to the individual needs of the athlete and can markedly impact the physiological response to training. Herein, we discuss various aspects of endurance training adaptations, nutritional strategies and their contributions to towards performance.


Assuntos
Desempenho Atlético/fisiologia , Treino Aeróbico/métodos , Metabolismo Energético/fisiologia , Estado Nutricional/fisiologia , Resistência Física/fisiologia , Cafeína/metabolismo , Dieta com Restrição de Carboidratos , Dieta Hiperlipídica , Jejum , Humanos , Necessidades Nutricionais
5.
Sports (Basel) ; 6(4)2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30400585

RESUMO

Purpose: To examine data reporting characteristics in sports nutrition. Methods: We examined 236 papers from ten journals published in 2016. The primary outcome was statistical variance associated with treatment (SD (correct) vs. SEM or CI). Secondary outcomes included the reporting of: (a) effect sizes (Y/N); (b) outcome prioritization (Y/N; primary, secondary, etc.) and (c) statistical variance relative to change from baseline (CI (correct) vs. SD or SEM). As tertiary/exploratory outcome, we examined whether authors stated a directed hypothesis. Statistical evaluation was performed using chi-square analyses. Results: We observed significant trends for all analyses (p < 0.001) and between category comparisons (p < 0.002). For the primary outcome, 128 (59%) articles correctly used SD to denote treatment variance, while 79 (36%) and 11 (5%) used SEM and CI, respectively. For secondary outcomes, 63 articles (29%) reported effect sizes, while 155 (71%) did not. Additionally, 188 articles (86%) did not prioritize outcomes, 134 articles (61%) stated no hypotheses and 40 (19%, out of 100) articles used CI to denote change scores vs. SD (19%, n = 41) and SEM (n = 10, 5%). Eight articles (4%) reported no variance terms. Conclusions: Overall, there are gaps regarding reporting in sports nutrition. Editors, journal publishers, and the field of exercise science alike should consider these outcomes and provide editorial staff, reviewers and authors with more concrete guidelines.

6.
J Spinal Cord Med ; 40(2): 246-249, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-26781683

RESUMO

OBJECTIVE: To review the outcome of 12 weeks of periodized, high-intensity interval training (HIT) in a man with chronic traumatic spinal cord injury (SCI). METHODS: A 42-year-old man (180 cm tall, 68.4 kg and 32.0% Fat) with a C8/T1 motor complete SCI took part in 12 weeks of 3 days per week arm crank ergometry (ACE) interval training. Training consisted of a combination of HIT that included three times 5  min at ∼70% Peak Power (WPeak) and 5  min recovery (HIT5); four times 2.5  min at ∼85% WPeak and 5  min recovery (HIT2.5); ten times 1  min at ∼110% WPeak and 2  min recovery (HIT1). Heart rate (HR) zones were set as <75% HRPeak (Z1), 75-89% (Z2), and 90+% (Z3) and used to monitor overall training efficacy. RESULTS: Thirty-six sessions that included 8 HIT5, 10 HIT2.5, and 5 HIT1 sessions were completed. WPeak and VO2 Peak improved about 45% and 52%, respectively, by week 6, without further improvement at week 12, HR TRIMP scores and power in training sessions trended upward over the 12-week program. CONCLUSIONS: Twelve weeks of HIT resulted in a large increase in peak aerobic power, as well as submaximal endurance performance in our participant. The early plateau in maximal testing supports the use of submaximal training assessment important in the long-term training monitoring for SCI.


Assuntos
Terapia por Exercício/métodos , Treinamento Intervalado de Alta Intensidade/métodos , Traumatismos da Medula Espinal/reabilitação , Adulto , Terapia por Exercício/efeitos adversos , Treinamento Intervalado de Alta Intensidade/efeitos adversos , Humanos , Masculino , Consumo de Oxigênio , Traumatismos da Medula Espinal/fisiopatologia
7.
Sports Med Open ; 2: 20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27034919

RESUMO

BACKGROUND: The study aims to compare how work-to-rest ratio (W:R) influences insulin sensitivity (Si) and inflammatory responses following one session of sprint interval training (SIT). METHODS: Thirteen men and two women completed a cross-over comparison of two SIT interventions-Tabata (TAB), 10 × 20-s sprints/10-s rest, and Wingate (WIN), 5 × 30-s sprints with 270-s rest. IL-6, IL-10, and TNF-α were assessed at baseline, immediately following, and 1 h after SIT, as well as prior to the 24-h post-exercise oral glucose tolerance tests (OGTTs). RESULTS: Participants were 23.8 (±3.5) years old and 180.0 (±10.2) cm tall, weighed 78.5 (13.0) kg, and had 16.9 (±6.5) % body fat, with a mean VO2Peak of 42.0 (±7.9) ml kg-1 min-1. There were no differences in total work (kJ) between TAB (64.7 ± 12.0) and WIN (68.0 ± 15.0). Mean (±95 % CI) Si 24 h changed -2.8 (-5.1, -0.5) from baseline after TAB and -3.9 (-6.9, -0.9) after WIN. Cytokines were measured in pg ml-1 and expressed as mean change (±95 % CI). IL-6 increased significantly immediately following SIT for TAB 0.70 (0.23, 1.17), and WIN 1.11 (0.60, 1.62), and remained elevated 1 h post SIT for TAB 1.10 (0.37, 1.83), and WIN 0.95 (0.26, 1.65). IL-10 showed a significant positive change immediately following exercise for TAB 1.53 (0.77, 2.29) and WIN 1.59 (0.58, 2.59). TNF-α also increased immediately both TAB 3.26 (1.57, 4.96) and WIN 3.05 (0.56, 5.54) and was directly proportional to IL-10 (r = 0.64, p < 0.0001). CONCLUSIONS: W:R did not alter either the inflammatory or metabolic response following SIT nor does SIT improve 24-h Si, despite increased levels of IL-10.

8.
J Spinal Cord Med ; 35(2): 107-12, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22525324

RESUMO

BACKGROUND: Functional electrical stimulation (FES) has been regularly used to offset several negative body composition and metabolic adaptations following spinal cord injury (SCI). However, the outcomes of many FES trials appear to be controversial and incoherent. OBJECTIVE: To document the potential consequences of several factors (e.g. pain, spasms, stress and lack of dietary control) that may have attenuated the effects on body composition and metabolic profile despite participation in 21 weeks of FES training. PARTICIPANT: A 29-year-old man with T6 complete SCI participated in 21 weeks of FES, 4 days per week. METHODS: Prior to and following training, the participant performed arm-crank-graded exercise testing to measure peak VO(2). Tests conducted included anthropometrics and dual energy X-ray absorptiometry body composition assessments, resting energy expenditure, plasma lipid profiles and intravenous glucose tolerance tests. RESULTS: The participant frequently reported increasing pain, stress and poor eating habits. VO(2) peak decreased by 2.4 ml/kg/minute, body mass increased by 8.5 kg, and body mass index increased from 25 to 28 kg/m(2). Waist and abdominal circumferences increased by 2-4 cm, while %fat mass increased by 5.5%. Absolute increases in fat mass and fat-free mass of 8.4 and 1 kg, respectively, were reported. Fasting and peak plasma glucose increased by 12 and 14.5%, while lipid panel profiles were negatively impacted. CONCLUSION: Failure to control for the listed negative emerging factors may obscure the expected body composition and metabolic profile adaptations anticipated from FES training.


Assuntos
Terapia por Estimulação Elétrica/métodos , Traumatismos da Medula Espinal/terapia , Absorciometria de Fóton , Adulto , Aminoácidos , Composição Corporal/fisiologia , Índice de Massa Corporal , Cromo , Metabolismo Energético , Terapia por Exercício/métodos , Humanos , Masculino , Metaboloma , Ácidos Nicotínicos
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