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1.
Int J Sports Physiol Perform ; : 1-11, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871342

RESUMO

PURPOSE: To investigate how cycling time-trial (TT) performance changes over a cycling season, both in a "fresh" state and in a "fatigued" state (durability). Additionally, the aim was to explore whether these changes are related to changes in underlying physiological factors such as gross efficiency, energy expenditure (EE), and substrate oxidation (fat oxidation [FatOx] and carbohydrate oxidation [CarbOx]). METHODS: Sixteen male semiprofessional cyclists visited the laboratory on 3 occasions during a cycling season (PRE, START, and IN) and underwent a performance test in both fresh and fatigued states (after 38.1 [4.9] kJ/kg), containing a submaximal warm-up for the measurement of gross efficiency, EE, FatOx, and CarbOx and a maximal TT of 1 (TT1min) and 10 minutes (TT10min). Results were compared across states (fresh vs fatigued) and periods (PRE, START, and IN). RESULTS: The average power output (PO) in TT1min decreased (P < .05) from fresh to fatigued state across all observed periods, whereas there was no change in the PO in TT10min. Over the course of the season, the PO in TT1min in the fatigued state improved more compared with the PO in TT1min in the fresh state. Furthermore, while EE did not significantly change, there was an increase in FatOx and a decrease in CarbOx toward the fatigued state. These changes diminished during the cycling season (IN), indicating a greater contribution of CarbOx in the fatigued state. CONCLUSIONS: TT1min performance is more sensitive to fatigue compared with TT10min. Also, during a cycling season, durability improves more when compared with fresh maximal POs, which is also observed in the changes in substrate oxidation.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38888560

RESUMO

BACKGROUND: This study investigates if countries are more focused on certain specializations (one day, climb, sprint, time trial [TT] and grand tour [GC]) in male professional road cycling and if this is possibly linked to the countries landscape (for example, does a mountainous country have more climbers?) and anthropometric characteristics (does the mountainous country also have lighter cyclists?) of their cyclists. METHODS: Body weight, height, procyclingstats (PCS) points per specialty were gathered from 1810 professional cyclists out of 15 countries, as well as the elevation span of those countries. To compare the anthropometric differences between different countries, height was normalized based on the average height of the countries' population, while BMI was used as a correction for body weight. RESULTS: The average anthropometrics (body weight and height) of professional cyclists in a country are related to the relative number of PCS points collected in GC, sprint and climb races. This means that when a country has shorter and lighter cyclists, they score relatively better in GC and climb races and vice versa for sprint races, which indicates that countries are focused on certain specialties. However, these relationships were not found for TT and one day PCS points. In addition, countries with larger cyclists have a less mountainous (elevation span) landscape compared to countries with lighter cyclists. CONCLUSIONS: The results suggest a selection bias towards smaller/lighter or taller/heavier cyclists in various countries, probably caused by the terrain of their home country, leading to missed opportunities for some cyclists to reach professional level.

3.
Int J Sports Physiol Perform ; 19(4): 329-330, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38402876
4.
Eur J Appl Physiol ; 124(6): 1659-1668, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38198009

RESUMO

PURPOSE: To determine if post-exercise heart rate variability, in the form of logged transformed root mean square of successive differences of the R-R intervals (LnRMSSD) can be measured reliably during the recovery from a submaximal cycle test and what the relationship of LnRMSSD is with training status of the cyclists. METHODS: Fourteen male cyclists participated in the reliability part for the study, which included performing six Lamberts Submaximal Cycle Test (LSCT), during which recovery LnRMSSD was measured over 30 s (LnRMSSD30 s), 60 s LnRMSSD60 s)and 90 s LnRMSSD90 s). In addition, fifty male and twenty female cyclists completed a peak power output (PPO) test (including VO2peak) and 40 km time trial (40 km TT) before which they performed the LSCT as a standardized warm-up. Relationships between the LnRMSSD and PPO, VO2peak and 40 km TT time were studied. RESULTS: Due to the design of the LSCT, submaximal heart and breathing rate were similar at the end of stage 3 of the LSCT, as well as during the recovery periods. The highest reliability was found in LnRMSSD60 s (ICC: 0.97) with a typical error of the measurement (TEM: 5.8%). In line with this the strongest correlations were found between LnRMSSD60 s and PPO (r = 0.93[male]; 0.85[female]), VO2peak (r = 0.71[male]; 0.63[female];) and 40 km TT (r = - 0.83[male]; - 0.63[female]). CONCLUSIONS: LnRMSSD60 s can be measured reliably after the LSCT and can predict PPO, VO2peak and 40 km TT performance well in trained-to-elite cyclists. These findings suggest that recovery LnRMSSD can potentially play an important role in monitoring and fine-tuning training prescriptions in trained-to-elite cyclists.


Assuntos
Ciclismo , Teste de Esforço , Frequência Cardíaca , Humanos , Masculino , Frequência Cardíaca/fisiologia , Ciclismo/fisiologia , Feminino , Adulto , Teste de Esforço/métodos , Reprodutibilidade dos Testes , Consumo de Oxigênio/fisiologia , Atletas
5.
Int J Sports Physiol Perform ; 19(3): 315-321, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134892

RESUMO

INTRODUCTION: This case study aimed to describe potential changes in neuromuscular activation and synergies after an 8-day cross-country mountain-bike stage race. METHODS: A peak power output test was performed 5 days before the race. Two days before the start and after 7 days of racing, the athlete performed a power-based Lamberts Submaximal Cycling Test, including surface electromyography, and completed a Daily Analysis of Life Demands of Athletes questionnaire. Neuromuscular activation, in terms of root mean square, timing (onset-offset) of muscle activation, and synergies, was obtained from electromyography recordings. RESULTS: The athlete reported an increase in symptoms of experienced stress after the stage race on the Daily Analysis of Life Demands of Athletes questionnaire. Both biceps femoris and tibialis anterior muscles showed a reduction in normalized amplitude after the stage race. In addition, the number of synergies that was necessary to describe neuromuscular activation increased from 2 to 3. CONCLUSIONS: In this case study, the increase in synergies suggests that, after the stage race, the athlete showed a more complex muscle-recruitment pattern. This may indicate that muscle coordination can change when muscle fatigue occurs; however, further research is needed to confirm these results in a larger sample.


Assuntos
Ciclismo , Músculos Isquiossurais , Humanos , Ciclismo/fisiologia , Músculo Esquelético/fisiologia , Fadiga Muscular/fisiologia , Eletromiografia
6.
Eur J Sport Sci ; 23(8): 1463-1471, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35938288

RESUMO

This study is governed by two aims: firstly, expanding the meagre knowledge store regarding the demands set by professional female road cycling and, secondly, ascertaining whether these demands vary in relation to different race-levels and race duration (single- or multi-day events). A total of 1349 female professional road races was analysed and demands (intensity, load and performance) were determined. Races were classified based on race level (i.e. Women's World Tour [WWT], level.1 and level.2 according to the International Cycling Federation) and race duration (single- or multi-day events). Differences were assessed with a multilevel random intercept model whilst the strength of said differences were indicated by Cohen's d (0-0.19 trivial; 0.20-0.59 small; 0.60-1.1.9 moderate; 1.20-1.99 large; ≥2.00 very large). In general, no moderate differences for load and intensity were noted for the different race levels. This result contrasts with data obtained from male road cycling. Moderate higher 3 and 5 min maximal mean power (MMP) values were noted in the WWT compared to Level.2 races. More substantial differences were found to exist between single- and multi-day races with single-day races presenting small to large higher load and intensity values. In addition, single-day races presented higher MMPs overall durations (5 s-60 min) although these differences can be rated trivial to small. This study contributes to the limited knowledge store describing demands in professional female cycling. The reported data provide valuable insights which may aid practitioners and/or coaches in preparing female professional cyclists for races.HighlightsWithin female professional cycling, some differences were noted in the demands (load, intensity and performances) set by different race levels. However, (in general), these differences were trivial to small, which contrasts with male professional cycling.More pronounced differences were noted in the demands set by single- and multi-day races. The load (Work done, eTRIMP and TSS) was moderate to large higher in single-day races. Differences in load are primarily caused by a combination of small higher duration and small higher intensity.No moderate differences in performance measures (i.e MMPs) were noted for different race levels or between single- and multi-day races.


Assuntos
Ciclismo , Esforço Físico , Feminino , Humanos
7.
J Sports Sci ; 40(19): 2159-2165, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36441611

RESUMO

This study aims to investigate the presence of the relative age effect (RAE) in (semi-)professional cycling, especially within selecting cyclists for Continental (CT) development teams. Data were collected from www.procyclingstats.com (PCS). Cyclists out of the top-25 countries of the PCS ranking that were part of a CT team between 2005 and 2016 and born between January 1986 and December 1997 were included (n = 2854). Distributions of cyclists in different birth quarters (Q1, Q2, Q3 and Q4) as well as for different starting years at CT level (U23year1, U23year2, U23year3 and U23year4) and reaching professional level or not were investigated using the Chi-square goodness-of-fit test. A RAE was found for cyclists that did not reach professional level, which can be explained by cyclists starting at CT level U23year1 and U23year2 (19 and 20 years old). Meaning that for cyclists at 19 and 20 years old, there is a selection bias towards relatively older (Q1) cyclists at the expense of relatively younger (Q4) cyclists. Within the cyclists that reached professional level, no RAE was found, indicating that the RAE diminishes at professional level. This study provides insight into possible selection errors while selecting cyclists for CT development teams.


Assuntos
Aptidão , Ciclismo , Humanos , Adulto Jovem , Adulto , Fatores Etários
9.
Eur J Trauma Emerg Surg ; 48(6): 4935-4941, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35802153

RESUMO

PURPOSE: Describing the epidemiological profile of patients with acute clavicle shaft fractures in a developing country public state hospital where mainly low- to middle-income patients are treated. METHODS: This is a retrospective analysis of all clavicle shaft fractures between 2008 and 2018 (10 years) based on Picture Archiving and Communication System at the second largest public hospital in South Africa. RESULTS: One thousand and three patients, 729 male and 274 female, were included in the epidemiological review. Most common causes of clavicle shaft fractures, in which 23% of cases presented with other injuries, were road accidents, falls and interpersonal violence. The majority of fractures were displaced and most (72%) were treated conservatively. Only 28% of patients were treated surgically, 61% with contoured plating and a relatively high 39% with intramedullary nails. CONCLUSION: The epidemiology of clavicle shaft fractures in a public hospital in a developing country, where the majority of patients hail from low- to middle-income backgrounds, differs substantially from developed countries. Although similar types of fractures were reported, differences were noted in terms of patients' age, causes of injury, associated injuries and treatment approaches.


Assuntos
Clavícula , Fraturas Ósseas , Humanos , Masculino , Feminino , Clavícula/lesões , Estudos Retrospectivos , Placas Ósseas , Países Desenvolvidos , África do Sul/epidemiologia , Resultado do Tratamento , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/cirurgia , Hospitais Públicos
10.
Cytokine ; 157: 155944, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35717881

RESUMO

BACKGROUND: Monitoring treatment response is an important precaution in spinal tuberculosis (TB), particularly when the condition was clinically diagnosed rather than bacteriologically confirmed and when drug susceptibility testing was not performed. Conventional monitoring measures have limitations and there is a need for favourable alternatives. Therefore, this study aimed to investigate changes in immune biomarkers over the course of treatment for spinal TB and to compare these responses to the conventional monitoring measure, erythrocyte sedimentation rate (ESR). METHODS: Patients with spinal TB were recruited from a tertiary hospital in the Western Cape, South Africa, and provided blood samples at 0, 3, 6, 9 and 12 months of TB treatment. Blood samples were analysed for ESR, using standard techniques, and for 19 cytokines, using a multiplex platform. Changes in ESR and cytokine levels were investigated using a mixed model ANOVA and Least Significant Difference post-hoc testing. RESULTS: Twenty-six patients with spinal TB were included in the study although only fifteen remained in follow-up at 12 months. Seven biomarkers changed significantly over the course of treatment (CRP, Fibrinogen, IFN-γ, Ferritin, VEGF-A, ApoA1 and NCAM, p < 0.01) with a further three showing a strong trend towards change (CCL1, CXCL9 and GDF-15, 0.05 ≥ p ≤ 0.06). Responsive biomarkers could be approximately grouped according to patterns of progressive, initial or delayed change. ESR performed similarly to CRP, Fibrinogen and IFN-γ with all showing significant decreases between 0, 6 and 12- months of treatment. Individual ESR responses were variable. DISCUSSION: Individual ESR responses may be unreliable and support the investigation of multi-marker approaches to evaluating treatment response in spinal TB. Biomarkers of treatment response identified in the current study require validation in a larger study, which may also incorporate aspects such as evaluating biomarkers within the first week of treatment and the inclusion of a healthy control group.


Assuntos
Tuberculose da Coluna Vertebral , Biomarcadores , Estudos de Coortes , Citocinas , Fibrinogênio , Humanos , Tuberculose da Coluna Vertebral/diagnóstico , Tuberculose da Coluna Vertebral/tratamento farmacológico
11.
J Strength Cond Res ; 36(7): 1998-2004, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35544349

RESUMO

ABSTRACT: Roete, AJ, Stoter, IK, Lamberts, RP, Elferink-Gemser, MT, and Otter, RTA. Introducing a method to quantify the specificity of training for races in speed skating. J Strength Cond Res 36(7): 1998-2004, 2022-The specificity of training for races is believed to be important for performance development. However, measuring specificity is challenging. This study aimed to develop a method to quantify the specificity of speed skating training for sprint races (i.e., 500 and 1,000 m), and explore the amount of training specificity with a pilot study. On-ice training and races of 10 subelite-to-elite speed skaters were analyzed during 1 season (i.e., 26 weeks). Intensity was mapped using 5 equal zones, between 4 m·s-1 to peak velocity and 50% to peak heart rate. Training specificity was defined as skating in the intensity zone most representative for the race for a similar period as during the race. During the season, eight 500 m races, seven 1,000 m races, and 509 training sessions were analyzed, of which 414 contained heart rate and 375 sessions contained velocity measures. Within-subject analyses were performed. During races, most time was spent in the highest intensity zone (Vz5 and HRz5). In training, the highest velocity zone Vz5 was reached 107 ± 28 times, with 9 ± 3 efforts (0.3 ± 0.1% training) long enough to be considered 500 m specific, 6 ± 5 efforts (0.3 ± 0.3% training) were considered 1,000 m specific. For heart rate, HRz5 was reached 151 ± 89 times in training, 43 ± 33 efforts (1.3 ± 0.9% training) were considered 500 m specific, and 36 ± 23 efforts (3.2 ± 1.7% training) were considered 1,000 m specific. This newly developed method enables the examination of training specificity so that coaches can control whether their intended specificity was reached. It also opens doors to further explore the impact of training specificity on performance development.


Assuntos
Desempenho Atlético , Patinação , Desempenho Atlético/fisiologia , Coleta de Dados , Frequência Cardíaca , Humanos , Projetos Piloto , Projetos de Pesquisa , Patinação/fisiologia
12.
Int J Sports Physiol Perform ; 17(7): 1070-1076, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35405635

RESUMO

INTRODUCTION: Maximal mean power output (MMP) is commonly used to describe the demands and performances of races in professional male cycling. In the female professional cyclist domain, however, there is limited knowledge regarding MMPs in races. Therefore, this study aimed to describe MMPs in female professional cycling races while investigating differences between TOP5 and NOT-TOP5 races. METHODS: Race data (N = 1324) were collected from 14 professional female cyclists between 2013 and 2019. Races were categorized as TOP5 or NOT-TOP5. The MMPs were consequently determined over a range of different time frames (5 s to 60 min). To provide these MMPs with additional context, 2 factors were determined: when these MMPs were attained in a race (based on duration and kilojoules spent [kJspent·kg-1]) and these MMPs relative to the cyclist's season's best MMP (MMP%best). RESULTS: Short-duration power outputs (≤1 min) were higher in TOP5 races compared with NOT-TOP5 races. In addition, the timing (both duration and kJspent·kg-1) of all MMPs was later and after more workload in the race in TOP5 compared with NOT-TOP5 races. In contrast, no difference in MMP%best was noted between TOP5 and NOT-TOP5 races. CONCLUSIONS: TOP5 races in female cycling are presented with higher short-duration MMPs (≤1 min) when compared with NOT-TOP5 races, and cyclists were able to reach a higher percentage of their seasonal best MMP when they were able to finish TOP5. In addition, these MMPs are performed later and after more kJspent·kg-1 in TOP5 versus NOT-TOP5 races, which confirms the importance of "fatigue resistance" in professional (female) cycling.


Assuntos
Ciclismo , Feminino , Humanos , Masculino , Fatores de Tempo
13.
J Sports Sci Med ; 21(1): 49-57, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35250333

RESUMO

Performance feedback can be essential for cyclists to help with pacing their efforts during competitions and also during standardized performance tests. However, the choice of feedback options on modern bike computers is limited. Moreover, little research on the effectiveness of the currently used feedback methods is available. In this study, two novel feedback variants using a bar or a tacho to visualize targets and deviation from targets were compared to a classic design using only numbers. Participants (6 female and 25 male trained to well-trained athletes) completed a protocol consisting of three heart rate-based tasks and one power-based task. The displays were compared with respect to their ability to guide athletes during their trials. Results showed lower root mean square error (RMSE) of the novel variants, but no significant effect of feedback variant on RMSE was found for both tasks (p > 0.05). However, when comparing the feedback variants on a person to person basis, significant differences were found for all investigated scenarios (p < 0.001). This leads to the conclusion that novel feedback variants can improve athletes' ability to follow heart rate-based and power-based protocols, but even better results might be achieved by individualizing the feedback.


Assuntos
Ciclismo , Retroalimentação Sensorial , Atletas , Feminino , Frequência Cardíaca , Humanos , Masculino
14.
Int J Sports Physiol Perform ; 17(5): 701-710, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35193109

RESUMO

PURPOSE: To present normative data for the record power profile of male professional cyclists attending to team categories and riding typologies. METHODS: Power output data registered from 4 professional teams during 8 years (N = 144 cyclists, 129,262 files, and 1062 total seasons [7 (5) per cyclist] corresponding to both training and competition sessions) were analyzed. Cyclists were categorized as ProTeam (n = 46) or WorldTour (n = 98) and as all-rounders (n = 65), time trialists (n = 11), climbers (n = 50), sprinters (n = 11), or general classification contenders (n = 7). The record power profile was computed as the highest maximum mean power (MMP) value attained for different durations (1 s to 240 min) in both relative (W·kg-1) and absolute units (W). RESULTS: Significant differences between ProTeam and WorldTour were found for both relative (P = .002) and absolute MMP values (P = .006), with WT showing lower relative, but not absolute, MMP values at shorter durations (30-60 s). However, higher relative and absolute MMP values were recorded for very short- (1 s) and long-duration efforts (60 and 240 min for relative MMP values and ≥5 min for absolute ones). Differences were also found regarding cyclists' typologies for both relative and absolute MMP values (P < .001 for both), with sprinters presenting the highest relative and absolute MMP values for short-duration efforts (5-30 s) and general classification contenders presenting the highest relative MMP values for longer efforts (1-240 min). CONCLUSIONS: The present results--obtained from the largest cohort of professional cyclists assessed to date-could be used to assess cyclists' capabilities and indicate that the record power profile can differ between cyclists' categories and typologies.


Assuntos
Ciclismo , Humanos , Masculino , Estações do Ano , Fatores de Tempo
15.
Int J Sports Physiol Perform ; 17(5): 682-686, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35168197

RESUMO

PURPOSE: To describe the record power profile of professional female cyclists and to assess potential differences based on the type of rider. METHODS: Power output data (32,028 files containing both training and competition sessions recorded) in 44 female professional cyclists during 1-6 years were analyzed. Cyclists were categorized as all-rounders, time trialists, climbers, or sprinters. The record power profile was calculated using the mean maximal power output (MMP) values attained by each cyclist for different-effort durations (5 s to 60 min) expressed in relative (W·kg-1), as well as absolute, power output (W). RESULTS: Participants' MMP averaged 15.3 (1.8) W·kg-1 for 5 seconds, 8.4 (0.8) W·kg-1 for 1 minute, 5.2 (0.5) W·kg-1 for 10 minutes, and 4.2 (0.4) W·kg-1 for 60 minutes. For short-duration efforts (5-30 s), sprinters attained the highest MMP results, with significantly higher relative (Hedges g = 1.40-2.31) or absolute (g = 4.48-8.06) values than the remainder of categories or climbers only, respectively. Time trialists attained the highest MMP for longer efforts, with higher relative values than both all-rounders and climbers when comparing efforts lasting 10 to 60 minutes (P < .05, g = 1.21-1.54). CONCLUSIONS: In professional female cyclists, the record power profile substantially differs based on the specific category of the rider. These findings provide unique insights into the physical capacities of female professional cyclists, as well as a benchmark for coaches and scientists aiming to identify talent in female cycling.


Assuntos
Ciclismo , Bases de Dados Factuais , Feminino , Humanos , Fatores de Tempo
16.
J Shoulder Elbow Surg ; 31(5): 906-913, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35158065

RESUMO

BACKGROUND: Two popular methods used to treat distal-third clavicle fractures are the traditional hook plate and the anatomically contoured locking plate. No consensus exists on whether one method is more effective than the other. Therefore, the aim of this study was to compare the efficacy of a traditional hook plate with that of an anatomically contoured locking plate augmented with coracoclavicular fixation in the treatment of distal-third clavicle fractures. METHODS: Enrolled patients were randomly assigned to either the hook plate group (n = 13) or the locking plate group (n = 17). Follow-up assessments (clinical and radiologic) were performed at 6 and 12 months postoperatively. RESULTS: In both groups, union was achieved in 91% of cases at 6 months and 100% at 12 months. No differences in Disabilities of the Arm, Shoulder and Hand (DASH) and Constant-Murley shoulder scores were noted between the hook plate and locking plate groups at 12 months. From 6 to 12 months, DASH scores improved in the hook plate group (P = .007) and Constant-Murley shoulder scores tended to improve (P = .075). Surgical time was longer in the locking plate group than in the hook plate group (P < .001). CONCLUSION: Similar functional outcomes and union rates were achieved in both groups at 12 months postoperatively. However, the improvement in DASH scores in the hook plate group from 6 to 12 months suggests that patients treated with an anatomically contoured locking plate make a quicker recovery than patients treated with a hook plate.


Assuntos
Clavícula , Fraturas Ósseas , Placas Ósseas/efeitos adversos , Clavícula/diagnóstico por imagem , Clavícula/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/etiologia , Fraturas Ósseas/cirurgia , Humanos , Estudos Prospectivos , Resultado do Tratamento
17.
J Strength Cond Res ; 36(7): 1847-1852, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32881840

RESUMO

ABSTRACT: Eken, MM, Withers, A, Flanagan, K, Burger, J, Bosch, A, and Lamberts, RP. Muscular activation patterns during exercise on the treadmill, stepper, and elliptical trainer. J Strength Cond Res 36(7): 1847-1852, 2022-Because of the low-impact, the stepper and elliptical trainer are popular alternatives to running when runners sustain running-related injuries. Muscular effort is expected to be lower during exercise on the stepper and elliptical trainer compared with running. The aim of this study was to quantify this by comparing muscular effort when exercising at similar moderate-to-high exercise intensities on a treadmill, stepper, and elliptical trainer. Seventeen well-trained runners (V̇o2max: 53.3 ml·min-1·kg-1 [male: n = 9], 44.8 ml·min-1·kg-1 [female: n = 8]; average peak treadmill running speed: 18.7 km·h-1 [male], 16.3 km·h-1 [female]) performed exercise at submaximal levels (60%-70%-80% of peak workload) on the treadmill, stepper, and elliptical trainer. Peak workload was determined during peak exercise tests on separate days. Surface electromyography was recorded from lower extremity muscles. Root-mean-squared (RMS) values were calculated and compared between exercise modalities and submaximal levels. Significance was set at p < 0.05. Root-mean-squared levels of lower extremity muscles were significantly reduced during exercise on the stepper and elliptical trainer compared with treadmill running (p < 0.05, except for quadriceps (p > 0.05). Overall, similar RMS levels were found on stepper and elliptical trainer (p > 0.05), whereas in several cases higher RMS levels were found on the stepper compared with elliptical trainer (p < 0.05). These findings support clinical expectations that exercise on the stepper and elliptical trainer reduces muscular effort up to 60% compared with (treadmill) running, and therefore can be effective training modalities during rehabilitation from running-related injuries by restricting impact on lower extremities.


Assuntos
Teste de Esforço , Corrida , Eletromiografia , Exercício Físico/fisiologia , Feminino , Humanos , Extremidade Inferior , Masculino , Consumo de Oxigênio/fisiologia , Corrida/fisiologia
18.
Arch Phys Med Rehabil ; 103(3): 481-487, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34653375

RESUMO

OBJECTIVE: Determine if spinal curvatures, deformities, as well as level of disability (due to back pain) changes with aging in adults with bilateral spastic cerebral palsy after receiving orthopedic interval surgery approach treatment in childhood. DESIGN: Consecutive case-series SETTING: Urban South Africa PARTICIPANTS: Twenty-seven ambulatory adults with cerebral palsy MAIN OUTCOME MEASURES: Spinal curvatures (scoliosis, thoracic kyphosis and lumbar lordosis) and deformities (spondylolysis and spondylolisthesis) were determined with X-rays, while the level of disability was assessed with the Oswestry Disability Index. RESULTS: The prevalence of spinal abnormalities were: 30% scoliosis (mild: <30°), 0% thoracic hyperkyphosis, 15% lumbar hyperlordosis, 0%; spondylolysis, and 0% spondylolisthesis. No changes in scoliosis and lumbar lordosis angles were observed, while the change in thoracic kyphosis angle was smaller than the minimal clinically important difference and moved closer toward the norm-values for typically developing adults. Level of disability remained similar with 63% reporting minimal disability, 26% moderate disability and 11% severe disability. No associations with spinal curvatures were found. CONCLUSIONS: No clinically meaningful changes in spinal curvatures, deformities and level of disability due to pain were seen during the 6 years follow-up period in adults with cerebral palsy who have been treated with interval surgery approach in childhood.


Assuntos
Paralisia Cerebral , Cifose , Lordose , Escoliose , Curvaturas da Coluna Vertebral , Espondilolistese , Adulto , Animais , Paralisia Cerebral/complicações , Seguimentos , Humanos , Cifose/complicações , Escoliose/epidemiologia , África do Sul/epidemiologia , Curvaturas da Coluna Vertebral/complicações , Curvaturas da Coluna Vertebral/epidemiologia , Espondilolistese/complicações
19.
Int J Sports Physiol Perform ; 17(2): 203-209, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560671

RESUMO

PURPOSE: This study evaluated the power profile of a top 5 result achieved in World Tour cycling races of varying types, namely: flat sprint finish, semi-mountain race with a sprint finish, semi-mountain race with uphill finish, and mountain races (MT). METHODS: Power output data from 33 professional cyclists were collected between 2012 and 2019. This large data set was filtered so that it only included top 5 finishes in World Tour races (18 participants and 177 races). Each of these top 5 finishes were subsequently classified as flat sprint finish, semi-mountain race with uphill finish, semi-mountain race with a sprint finish, and MT based on set criteria. Maximal mean power output (MMP) for a wide range of durations (5 s to 60 min), expressed in both absolute (in Watts) and relative terms (in Watts per kilogram), were assessed for each race type. RESULT: Short-duration power outputs (<60 s), both in relative and in absolute terms, are of higher importance to be successful in flat sprint finish and semi-mountain race with a sprint finish. Longer-duration power outputs (≥3 min) are of higher importance to be successful in semi-mountain race with uphill finish and MT. In addition, relative power outputs of >10 minutes seem to be a key determining factor for success in MT. These race-type specific MMPs of importance (ie, short-duration MMPs for sprint finishes, longer-duration MMPs for races with more elevation gain) are performed at a wide range (80%-97%) of the cyclist's personal best MMP. CONCLUSIONS: This study shows that the relative importance of certain points on the power-duration spectrum varies with different race types and provides insight into benchmarks for achieving a result in a World Tour cycling race.


Assuntos
Ciclismo , Humanos , Fatores de Tempo
20.
Eur J Sport Sci ; 22(10): 1586-1594, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34503394

RESUMO

This study aimed to investigate whether (semi-)professional cyclists' execution of a training programme differs from the coach's designed training programme. Also, the study sought to ascertain, in instances where the training sessions were indeed executed as designed by the coach, whether the perception of the cyclists differed from the intention of the coach. This study highlights the differences between the coach and the individual cyclist. In total, 747 training sessions were collected from 11 (semi-)professional cyclists. Rating of Perceived Exertion (RPE) and session Rating of Perceived Exertion (sRPE) were compared with intended RPE (iRPE) and intended sRPE (isRPE), planned by the coach. Pearson's correlation, regression coefficients and Typical Error of Estimate (TEE) were used to identify differences between the executed and planned training sessions. Moderate to large TEEs were noted between executed and intended sRPE, which indicates that cyclists do not always execute the training programme planned by the coach. Furthermore, when the training was executed as planned by the coach, very large correlations but moderate to very large TEEs were noted between cyclists' (s)RPE and the coach's i(s)RPE, with unique individual regression coefficients. This indicates that the relationship between RPE and iRPE is unique to each cyclist. Both the different execution and perception of the training programme by the individual cyclists could cause an impaired training adaptation. Therefore, the coach must pay attention to the perception of training sessions by the individual cyclist. Improved individual management of training load could result in the optimisation of the proposed training programme.


Assuntos
Condicionamento Físico Humano , Frequência Cardíaca , Humanos , Intenção , Percepção , Esforço Físico
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