Performance Relationships in Timed and Mass-Start Events for Elite Omnium Cyclists

2017 ◽  
Vol 12 (5) ◽  
pp. 628-633 ◽  
Author(s):  
Kathryn E. Phillips ◽  
Will G. Hopkins

Purpose:To explore the extent to which factors that determine performance transfer within and between time-trial and mass-start events in the track-cycling Omnium.Methods:Official finish rank in the 3 time-trial events, in the 3 mass-start events, and in the competition overall were collated in 20 international Omnium competitions between 2010 and 2014 for 196 male and 140 female cyclists. Linear mixed modeling of the log-transformed finish time for the time-trial events and of log-transformed finish rank for all events and final rank provided estimates of within-athlete race-to-race changes in performance and average betweenathletes differences across a season. These estimates were converted to various correlations representing relationships within and between the various events and final rank.Results:Intraclass correlation coefficients, representing race-to-race reproducibility of performance, were similar whether derived from finish rank or finish time for the time-trial events. Log-transformed finish ranks are therefore a suitable measure to assess and compare performance in time-trial and mass-start events. Omnium cyclists were more predictable in their performances from race to race in the timed events, whereas reduced predictability was observed in mass-start events. Interevent correlations indicated stronger links in performance between the timed disciplines, whereas performance in any of the mass-start events had only a slight positive relationship with performance in the other massstart events and little or no relationship with the timed events.Conclusions:Further investigation is warranted to determine whether factors related to performance in mass-start events can be identified to improve reproducibility or whether variability in performance results from random chance.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
YoungHwan Choi ◽  
Se Jin Oh ◽  
Jong Hee Lee

AbstractSkin hydration is generally evaluated using devices that measure capacitance or conductance. A new technology (Biodisplay) was developed to provide accurate measurements of skin hydration at the contact site. This study aimed to test the reliability of the Biodisplay by comparing its performance results with those of similar devices currently used to objectively assess skin hydration. For each of the 30 participants, skin hydration was measured at each of the defined points on the forearm three times using the Biodisplay and a Hydration probe (HP), an objective measurement device of skin hydration. We also evaluated skin hydration of the arm using both tools after applying moisturizers to evaluate interferences from skin care products. The reliability and reproducibility of each device were analyzed by intraclass correlation coefficients (ICC), and the correlation of the two devices was evaluated by Pearson’s correlation coefficients (PCC). The Biodisplay demonstrated moderate-to-excellent reliability (ICC: (0.741–0.980)), but lower reliability than the HP (ICC: (0.953–0.980)). The skin hydration measurements made by the two devices were demonstrated to be significantly correlated, showing moderate correlations (PCC: 0.601). The Biodisplay can provide reasonably reliable and accurate measurements for skin hydration with the strong points of portability and accessibility.


2013 ◽  
Vol 8 (5) ◽  
pp. 490-495 ◽  
Author(s):  
Jeremy M. Sheppard ◽  
Sophia Nimphius ◽  
Greg G. Haff ◽  
Tai T. Tran ◽  
Tania Spiteri ◽  
...  

Purpose:Appropriate and valid testing protocols for evaluating the physical performances of surfing athletes are not well refined. The purpose of this project was to develop, refine, and evaluate a testing protocol for use with elite surfers, including measures of anthropometry, strength and power, and endurance.Methods:After pilot testing and consultation with athletes, coaches, and sport scientists, a specific suite of tests was developed. Forty-four competitive junior surfers (16.2 ± 1.3 y, 166.3 ± 7.3 cm, 57.9 ± 8.5 kg) participated in this study involving a within-day repeated-measures analysis, using an elite junior group of 22 international competitors (EJG), to establish reliability of the measures. To reflect validity of the testing measures, a comparison of performance results was then undertaken between the EJG and an age-matched competitive junior group of 22 nationally competitive surfers (CJG).Results:Percent typical error of measurement (%TEM) for primary variables gained from the assessments ranged from 1.1% to 3.0%, with intraclass correlation coefficients ranging from .96 to .99. One-way analysis of variance revealed that the EJG had lower skinfolds (P = .005, d = 0.9) than the CJG, despite no difference in stature (P = .102) or body mass (P = .827). The EJG were faster in 15-m sprint-paddle velocity (P < .001, d = 1.3) and had higher lower-body isometric peak force (P = .04, d = 0.7) and superior endurance-paddling velocity (P = .008, d = 0.9).Conclusions:The relatively low %TEM of these tests in this population allows for high sensitivity to detect change. The results of this study suggest that competitively superior junior surfers are leaner and possess superior strength, paddling power, and paddling endurance.


2019 ◽  
Vol 14 (4) ◽  
pp. 472-477 ◽  
Author(s):  
Kathryn E. Phillips ◽  
Will G. Hopkins

Purpose: To further the understanding of elite athlete performance in complex race environments by examining the changes in cyclists’ performance between solo time trials and head-to-head racing in match-sprint tournaments. Methods: Analyses were derived from official results of cyclists in 61 elite international sprint tournaments (2000–2016), incorporating the results of 2060 male and 1969 female head-to-head match races. Linear mixed modeling of log-transformed qualification and finish ranks was used to determine estimates of performance predictability as intraclass correlation coefficients. Correlations between qualifying performance and final tournament rank were also calculated. Chances of winning head-to-head races were estimated adjusting for the difference in the cyclists’ qualifying times. All effects were evaluated using magnitude-based inference. Results: Minor differences in predictability between qualification time trial and final tournament rank were suggestive of more competitiveness among men in the overall tournament. Performance in the qualification time trial was strongly correlated with, but not fully indicative of, performance in the overall tournament. Correspondingly, being the faster qualifier had a large positive effect on the chances of winning a head-to-head race, but small substantial differences between riders remained after adjustment for time-trial differentials. Conclusions: The present study provides further insight into how real-world competition data can be used to investigate elite athlete performance in sports where athletes must directly interact with their opponents. For elite match-sprint cyclists, qualifying time-trial performance largely determines success in the overall tournament, but there is evidence of a consistent match-race ability that modifies the chances of winning head-to-head races.


1991 ◽  
Vol 34 (5) ◽  
pp. 989-999 ◽  
Author(s):  
Stephanie Shaw ◽  
Truman E. Coggins

This study examines whether observers reliably categorize selected speech production behaviors in hearing-impaired children. A group of experienced speech-language pathologists was trained to score the elicited imitations of 5 profoundly and 5 severely hearing-impaired subjects using the Phonetic Level Evaluation (Ling, 1976). Interrater reliability was calculated using intraclass correlation coefficients. Overall, the magnitude of the coefficients was found to be considerably below what would be accepted in published behavioral research. Failure to obtain acceptably high levels of reliability suggests that the Phonetic Level Evaluation may not yet be an accurate and objective speech assessment measure for hearing-impaired children.


Author(s):  
Marcos A Soriano ◽  
G Gregory Haff ◽  
Paul Comfort ◽  
Francisco J Amaro-Gahete ◽  
Antonio Torres-González ◽  
...  

The aims of this study were to (I) determine the differences and relationship between the overhead press and split jerk performance in athletes involved in weightlifting training, and (II) explore the magnitude of these differences in one-repetition maximum (1RM) performances between sexes. Sixty-one men (age: 30.4 ± 6.7 years; height: 1.8 ± 0.5 m; body mass 82.5 ± 8.5 kg; weightlifting training experience: 3.7 ± 3.5 yrs) and 21 women (age: 29.5 ± 5.2 yrs; height: 1.7 ± 0.5 m; body mass: 62.6 ± 5.7 kg; weightlifting training experience: 3.0 ± 1.5 yrs) participated. The 1RM performance of the overhead press and split jerk were assessed for all participants, with the overhead press assessed on two occasions to determine between-session reliability. The intraclass correlation coefficients (ICC) and 95% confidence intervals showed a high reliability for the overhead press ICC = 0.98 (0.97 – 0.99). A very strong correlation and significant differences were found between the overhead press and split jerk 1RM performances for all participants (r = 0.90 [0.93 – 0.85], 60.2 ± 18.3 kg, 95.7 ± 29.3 kg, p ≤ 0.001). Men demonstrated stronger correlations between the overhead press and split jerk 1RM performances (r = 0.83 [0.73-0.90], p ≤ 0.001) compared with women (r = 0.56 [0.17-0.80], p = 0.008). These results provide evidence that 1RM performance of the overhead press and split jerk performance are highly related, highlighting the importance of upper-limb strength in the split jerk maximum performance.


Dysphagia ◽  
2021 ◽  
Author(s):  
Sofie Albinsson ◽  
Lisa Tuomi ◽  
Christine Wennerås ◽  
Helen Larsson

AbstractThe lack of a Swedish patient-reported outcome instrument for eosinophilic esophagitis (EoE) has limited the assessment of the disease. The aims of the study were to translate and validate the Eosinophilic Esophagitis Activity Index (EEsAI) to Swedish and to assess the symptom severity of patients with EoE compared to a nondysphagia control group. The EEsAI was translated and adapted to a Swedish cultural context (S-EEsAI) based on international guidelines. The S-EEsAI was validated using adult Swedish patients with EoE (n = 97) and an age- and sex-matched nondysphagia control group (n = 97). All participants completed the S-EEsAI, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Oesophageal Module 18 (EORTC QLQ-OES18), and supplementary questions regarding feasibility and demographics. Reliability and validity of the S-EEsAI were evaluated by Cronbach’s alpha and Spearman correlation coefficients between the domains of the S-EEsAI and the EORTC QLQ-OES18. A test–retest analysis of 29 patients was evaluated through intraclass correlation coefficients. The S-EEsAI had sufficient reliability with Cronbach’s alpha values of 0.83 and 0.85 for the “visual dysphagia question” and the “avoidance, modification and slow eating score” domains, respectively. The test–retest reliability was sufficient, with good to excellent intraclass correlation coefficients (0.60–0.89). The S-EEsAI domains showed moderate correlation to 6/10 EORTC QLQ-OES18 domains, indicating adequate validity. The patient S-EEsAI results differed significantly from those of the nondysphagia controls (p < 0.001). The S-EEsAI appears to be a valid and reliable instrument for monitoring adult patients with EoE in Sweden.


Author(s):  
Jens Sörensen ◽  
Jonny Nordström ◽  
Tomasz Baron ◽  
Stellan Mörner ◽  
Sven-Olof Granstam ◽  
...  

Abstract Aim To develop a method for diagnosing left ventricular (LV) hypertrophy from cardiac perfusion 15O-water positron emission tomography (PET). Methods We retrospectively pooled data from 139 subjects in four research cohorts. LV remodeling patterns ranged from normal to severe eccentric and concentric hypertrophy. 15O-water PET scans (n = 197) were performed with three different PET devices. A low-end scanner (66 scans) was used for method development, and remaining scans with newer devices for a blinded evaluation. Dynamic data were converted into parametric images of perfusable tissue fraction for semi-automatic delineation of the LV wall and calculation of LV mass (LVM) and septal wall thickness (WT). LVM and WT from PET were compared to cardiac magnetic resonance (CMR, n = 47) and WT to 2D-echocardiography (2DE, n = 36). PET accuracy was tested using linear regression, Bland–Altman plots, and ROC curves. Observer reproducibility were evaluated using intraclass correlation coefficients. Results High correlations were found in the blinded analyses (r ≥ 0.87, P < 0.0001 for all). AUC for detecting increased LVM and WT (> 12 mm and > 15 mm) was ≥ 0.95 (P < 0.0001 for all). Reproducibility was excellent (ICC ≥ 0.93, P < 0.0001). Conclusion 15O-water PET might detect LV hypertrophy with high accuracy and precision.


Author(s):  
Igor Junio de Oliveira Custódio ◽  
Gibson Moreira Praça ◽  
Leandro Vinhas de Paula ◽  
Sarah da Glória Teles Bredt ◽  
Fabio Yuzo Nakamura ◽  
...  

This study aimed to analyze the intersession reliability of global positioning system (GPS-based) distances and accelerometer-based (acceleration) variables in small-sided soccer games (SSG) with and without the offside rule, as well as compare variables between the tasks. Twenty-four high-level U-17 soccer athletes played 3 versus 3 (plus goalkeepers) SSG in two formats (with and without the offside rule). SSG were performed on eight consecutive weeks (4 weeks for each group), twice a week. The physical demands were recorded using a GPS with an embedded triaxial accelerometer. GPS-based variables (total distance, average speed, and distances covered at different speeds) and accelerometer-based variables (Player Load™, root mean square of the acceleration recorded in each movement axis, and the root mean square of resultant acceleration) were calculated. Results showed that the inclusion of the offside rule reduced the total distance covered (large effect) and the distances covered at moderate speed zones (7–12.9 km/h – moderate effect; 13–17.9 km/h – large effect). In both SSG formats, GPS-based variables presented good to excellent reliability (intraclass correlation coefficients – ICC > 0.62) and accelerometer-based variables presented excellent reliability (ICC values > 0.89). Based on the results of this study, the offside rule decreases the physical demand of 3 versus 3 SSG and the physical demands required in these SSG present high intersession reliability.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Minjeong Kim ◽  
Ja Young Oh ◽  
Seon Ha Bae ◽  
Seung Hyeun Lee ◽  
Won Jun Lee ◽  
...  

AbstractWe evaluated the reliability and validity of the 5-scale grading system to interpret the point-of-care immunoassay for tear matrix metalloproteinase (MMP)-9. Six observers graded red bands of photographs of the readout window in MMP-9 immunoassay kit (InflammaDry) two times with 2-week interval based on the 5-scale grading system (i.e. grade 0–4). Interobserver and intraobserver reliability were evaluated using intraclass correlation coefficients. The interobserver agreements were analyzed according to the severity of tear MMP-9 expression. To validate the system, a concentration calibration curve was made using MMP-9 solutions with reference concentrations, then the distribution of MMP-9 concentrations was analyzed according to the 5-scale grading system. Both intraobserver and interobserver reliability was excellent. The readout grades were significantly correlated with the quantified colorimetric densities. The interobserver variance of readout grades had no correlation with the severity of the measured densities. The band density continued to increase up to a maximal concentration (i.e. 5000 ng/mL) according to the calibration curve. The difference of grades reflected the change of MMP-9 concentrations sensitively, especially between grade 2 and 4. Together, our data indicate that the subjective 5-scale grading system in the point-of-care MMP-9 immunoassay is an easy and reliable method with acceptable accuracy.


Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3065
Author(s):  
Ernest Kwesi Ofori ◽  
Shuaijie Wang ◽  
Tanvi Bhatt

Inertial sensors (IS) enable the kinematic analysis of human motion with fewer logistical limitations than the silver standard optoelectronic motion capture (MOCAP) system. However, there are no data on the validity of IS for perturbation training and during the performance of dance. The aim of this present study was to determine the concurrent validity of IS in the analysis of kinematic data during slip and trip-like perturbations and during the performance of dance. Seven IS and the MOCAP system were simultaneously used to capture the reactive response and dance movements of fifteen healthy young participants (Age: 18–35 years). Bland Altman (BA) plots, root mean square errors (RMSE), Pearson’s correlation coefficients (R), and intraclass correlation coefficients (ICC) were used to compare kinematic variables of interest between the two systems for absolute equivalency and accuracy. Limits of agreements (LOA) of the BA plots ranged from −0.23 to 0.56 and −0.21 to 0.43 for slip and trip stability variables, respectively. The RMSE for slip and trip stabilities were from 0.11 to 0.20 and 0.11 to 0.16, respectively. For the joint mobility in dance, LOA varied from −6.98–18.54, while RMSE ranged from 1.90 to 13.06. Comparison of IS and optoelectronic MOCAP system for reactive balance and body segmental kinematics revealed that R varied from 0.59 to 0.81 and from 0.47 to 0.85 while ICC was from 0.50 to 0.72 and 0.45 to 0.84 respectively for slip–trip perturbations and dance. Results of moderate to high concurrent validity of IS and MOCAP systems. These results were consistent with results from similar studies. This suggests that IS are valid tools to quantitatively analyze reactive balance and mobility kinematics during slip–trip perturbation and the performance of dance at any location outside, including the laboratory, clinical and home settings.


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