Performance Laboratory

Leeds, United Kingdom

Performance Laboratory

Leeds, United Kingdom
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Inoue A.,Estácio de Sá University | Inoue A.,Physical Education Center Admiral Adalberto Nunes | Inoue A.,Performance Laboratory | Inoue A.,University of Sao Paulo | And 6 more authors.
Gazzetta Medica Italiana Archivio per le Scienze Mediche | Year: 2017

BACKGROUND: critical power (cp) is considered a variable for measuring and predicting aerobic performance. however, there is no evidence supporting the use of cp with mountain biking aerobic performance. the purpose of this study was to examine the correlation between cp and cross-country (Xco) race time. METHODS: Seventeen XCO riders (30.2±5.6 years, 67.9±6.3 kg, 174.8±5.5 cm, 7.0±2.3% body fat, 64.4±4.5 mL·kg-1·min-1 vo2max, 272.5±13.5 W estimated CP) classified as performance cohort level three (PL3 - trained) completed three separate testing sessions and a XCO race. In the first session, the participants performed a maximal incremental test for the determination of maximal oxygen uptake and peak power output (ppo). in the second and third sessions, the participants performed a time limit test for the determination of cp and in the fourth session, they performed a Xco race. RESULTS: Significant correlations were identified between CP relative to body mass (r=-0.64, 95% CI -0.85 to -0.23, P<0.01) and PPO relative to body mass (r=-0.80, 95% CI -0.92 to -0.52, P<0.001) with race time. CONCLUSIONS: The findings of the study support the use of CP for assessing mountain biking racing performance. however, the association between Xco performance and ppo relative to body mass was greater than the association between XCO performance and CP. Therefore, the traditional progressive maximum test is sufficient to predict XCO performance. © 2016 EDIZIONI MINERVA MEDICA.


Inoue A.,Estácio de Sá University | Inoue A.,Physical Education Center Admiral Adalberto Nunes | Inoue A.,Performance Laboratory | Inoue A.,University of Sao Paulo | And 10 more authors.
PLoS ONE | Year: 2016

Objectives The current study compared the effects of high-intensity aerobic training (HIT) and sprint interval training (SIT) on mountain biking (MTB) race simulation performance and physiological variables, including peak power output (PPO), lactate threshold (LT) and onset of blood lactate accumulation (OBLA). Methods Sixteen mountain bikers (mean ± SD: age 32.1 ± 6.4 yr, body mass 69.2 ± 5.3 kg and VO2max 63.4 ± 4.5 mL-kg-1-min-1) completed graded exercise and MTB performance tests before and after six weeks of training. The HIT (7-10 x [4-6 min-highest sustainable intensity / 4-6 min-CR100 10-15]) and SIT (8-12 x [30 s-all-out intensity / 4 min-CR100 10-15]) protocols were included in the participants' regular training programs three times per week. Results Post-training analysis showed no significant differences between training modalities (HIT vs. SIT) in body mass, PPO, LT or OBLA (p = 0.30 to 0.94). The Cohen's d effect size (ES) showed trivial to small effects on group factor (p = 0.00 to 0.56). The interaction between MTB race time and training modality was almost significant (p = 0.08), with a smaller ES in HIT vs. SIT training (ES = -0.43). A time main effect (pre- vs. post-phases) was observed in MTB race performance and in several physiological variables (p = 0.001 to 0.046). Co-variance analysis revealed that the HIT (p = 0.043) group had significantly better MTB race performance measures than the SIT group. Furthermore, magnitude-based inferences showed HIT to be of likely greater benefit (83.5%) with a lower probability of harmful effects (0.8%) compared to SIT. Conclusion The results of the current study suggest that six weeks of either HIT or SIT may be effective at increasing MTB race performance; however, HIT may be a preferable strategy. © 2016 Inoue et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


News Article | December 23, 2016
Site: www.eurekalert.org

CLEMSON, South Carolina -- A team of Clemson University researchers and an Upstate businessman believe they can help make football a little safer by creating a facemask that can help reduce the severity of head injuries by increasing overall helmet protection. The researchers are Gregory Batt, an assistant professor in the Clemson food, nutrition and packaging sciences department; John DesJardins, an associate professor of bioengineering and director of the Laboratory of Orthopaedic Design and Engineering; and Alex Bina, a doctoral student in bioengineering who also is a graduate research assistant in food, nutrition and packaging sciences. They are teaming up with Jay Elmore, owner of Green Gridiron to determine how future designs of facemasks can help improve the overall safety of football helmets. The team has received a nearly $50,000 grant from the Robert H. Brooks Sports Science Institute for their study "Quantifying the Impact Performance of Football Helmet Facemasks." "What we're working on is trying to understand and evaluate the role a football helmet facemask plays in the overall impact performance of a football helmet system," Bina said. "We're doing this by evaluating the mechanisms by which forces are transmitted from the facemask through the rest of the helmet system upon impact." The forces Bina refers to are g-forces, which result from accelerations experienced by the head during impact. Bina and the rest of the team are working to make helmets more safe by creating a facemask that can help the helmet transfer g-forces away from the head. Traditional helmet design produces protective equipment that gradually decelerates the head upon impact. Facemasks are to prevent direct contact with players' faces. "Ideally, facemasks would deform slightly in order to produce gradual head deceleration, but not so much so as to put players at risk of injuring their faces," Bina said. "However, the deformation properties of existing facemask designs are not available, making it impossible for doctors. trainers and parents to make informed decisions when purchasing a facemask for their helmet system. The first step in our facemask impact performance experimentation is to generate a ranking system of existing facemask designs based on their ability to deform." According to the National Institutes of Health, head injuries can occur when there is rapid change in the movement of the head, such as when a football player is tackled. Any significant force can have a detrimental effect on brain tissue. Batt said there are many different situations on a football field that cause rapid changes in velocity, or g-forces. "These situations can be player-to-player or player-to-turf interactions," Batt said. "These rapid changes in velocity can cause the player's brain to move around and smash against the player's skull. This trauma can result in a brain injury." The Clemson team is using a linear drop tower system for its tests. Helmets tested in this manner are placed on an anthropomorphic head model and dropped from a specific height to generate a simulated football head impact. In the lab, the researchers said the linear drop tower testing system shows fewer than three impacts of 12 mph can cause permanent damage to facemasks. Football players of all positions commonly reach maximum velocities above 12 mph, especially on kickoff returns and coverage plays in both games and practice. Using the linear drop system introduces many variables to the overall performance of a facemask design, including the helmet's padding structure, the helmet's outer shell and the chin strap buckles. Some facemask designs only fit one helmet style, but testing the entire helmet system will not specifically determine how one facemask performs compared to another. "Because facemasks have been overlooked by the head impact research community, it is important to start at the structural and material level to determine appropriate facemask designs, then move into studying the method with which the facemask is attached to the helmet outer shell," Bina said. The facemask tests are being conducted in the head impact section, the Clemson Helmet Impact Performance Laboratory (CHIP LAB) of the Sonoco Packaging Science laboratory on the Clemson campus. Some variables the researchers are studying include structural stiffness, resistance to permanent deformation and energy absorption. Over the course of a season, an NFL or college team may experience a handful of permanent facemask deformations in game situations, requiring the equipment staff to replace the facemasks on the sideline. However, at the youth level, the course of a season's worth of impacts in practices and games can permanently damage facemasks beyond repair. Facemask reconditioning service providers, such as Green Gridiron in Greenville, select permanently damaged masks from youth, high school, college and professional programs and removes them from circulation. Undeformed masks are recoated and returned to teams. Jay Elmore, founder and chief executive officer of Green Gridiron, believes in the Clemson facemask research. Elmore donated equipment to the Clemson professors for their research. "I have been involved in football helmet facemask testing for more than six years and have struggled with inconsistent results," Elmore said. "As a provider of football facemasks for teams across the country at various levels of play, we look forward to the testing methods developed at Clemson University and their ability to provide science-based and data-driven criteria for facemask selection and future facemask development." "When we set out to investigate facemask performance in general, there was no literature out there," DesJardins said. "From a research university's perspective, that's the perfect thing to do: research something that is important but no one has done before." Football is a major sport at Clemson, so it is only natural a study on how to make the sport safer would be conducted by Clemson researchers. "Anytime someone plays a contact sport, there's a chance they will suffer a concussion," said Danny Poole, Clemson's director of sports medicine. "Football helmets were developed to help stop skull fractures, not concussions. If a helmet can be created that would stop concussions, everyone would buy it." Statistics from the Centers for Disease Control about 75 percent of traumatic brain injuries that occur each year are concussions. Sports is second only to car crashes as the leading cause of brain injury among people aged 15 to 24 years.


Komar J.,Performance Laboratory | Komar J.,University of Rouen | Seifert L.,University of Rouen | Thouvarecq R.,University of Rouen
Movement and Sports Sciences - Science et Motricite | Year: 2015

In this review, we revisit the concept of movement variability in motor expertise from the perspective of complex systems theory; we do so by defining performers and their relationships with the environment. The complex systems perspective places the focus on the functional role of movement variability as an emergent response to interacting constraints as performers pursue task-goals. We therefore show how the shift in theoretical focus towards the functional role of variability has entailed a reconsideration of the way this key property of motor expertise should be assessed. We then present the main theoretical issues surrounding movement variability and expertise through examples of empirical applications of the relevant tools and concepts in the sport and movement sciences. © ACAPS, EDP Sciences, 2015.


Botton F.,Performance Laboratory | Botton F.,University of Lyon | Hautier C.,University of Lyon | Eclach J.-P.,Performance Laboratory
Journal of Strength and Conditioning Research | Year: 2011

The aim of this study was to estimate, using video analysis, what proportion of the total energy expenditure during a tennis match is accounted for by aerobic and anaerobic metabolism, respectively. The method proposed involved estimating the metabolic power (MP) of 5 activities, which are inherent to tennis: walking, running, hitting the ball, serving, and sitting down to rest. The energy expenditure concerned was calculated by sequencing the activity by video analysis. A bioenergetic model calculated the aerobic energy expenditure (EEO2mod) in terms of MP, and the anaerobic energy expenditure was calculated by subtracting this (MP 2 EEO2mod). Eight tennis players took part in the experiment as subjects (mean 6 SD: age 25.2 6 1.9 years, weight 79.3 6 10.8 kg, VO2max 54.4 6 5.1 ml-kg21-min21). The players started off by participating in 2 games while wearing the K4b2, with their activity profile measured by the video analysis system, and then by playing a set without equipment but with video analysis. There was no significant difference between calculated and measured oxygen consumptions over the 16 games (p = 0.763), and these data were strongly related (r = 0.93, p < 0.0001). The EEO2mod was quite weak over all the games (49.4 6 4.8% VO2max), whereas the MP during points was up to 2 or 3 times the VO2max. Anaerobic metabolism reached 32% of the total energy expenditure across all the games 67% for points and 95% for hitting the ball. This method provided a good estimation of aerobic energy expenditure and made it possible to calculate the anaerobic energy expenditure. This could make it possible to estimate the metabolic intensity of training sessions and matches using video analysis. © 2011 National Strength and Conditioning Association.


Inoue A.,Gama Filho University | Inoue A.,Performance Laboratory | Safilho A.S.,Gama Filho University | Safilho A.S.,Performance Laboratory | And 4 more authors.
Journal of Strength and Conditioning Research | Year: 2012

Despite its apparent relevance, there is no evidence supporting the importance of anaerobic metabolism in Olympic crosscountry mountain biking (XCO). The purpose of this study was to examine the correlation between XCO race time and performance indicators of anaerobic power. Ten XCO riders (age: 28 6 5 years; weight: 68.7 ± 7.7 kg; height: 177.9 ± 7.4 cm; estimated body fat: 5.7 ± 2.8%; estimated VO2max: 68.4 ± 5.7 ml kg-1 min-1) participating in the Lagos Mountain Bike Championship (Brazil) completed 2 separate testing sessions before the race. In the first session, after anthropometric assessments were performed, the cyclists completed a single 30-second Wingate (WIN) test and an intermittent tests consisting of 5 × 30- second WIN tests (50% of the single WIN load) with 30 seconds of recovery between trials. In the second session, the riders performed a maximal incremental test. A significant correlation was found between race time and maximal power on the 5× WIN test (r = -0.79, IC 95% -0.94 to -0.32, p = 0.006) and the mean average power on the 5× WIN test normalized by body mass (r = -0.63, IC95% 20.90 to 20.01, p = 0.048). The finding of the study supports the use of anaerobic tests for assessing mountain bikers participating in XCO competitions and suggests that anaerobic power is an important determinant of performance. © 2012 National Strength and Conditioning Association.


PubMed | Schulthess Clinic, Performance Laboratory, Estácio de Sá University, State University of Rio de Janeiro and Federal University of Rio de Janeiro
Type: Comparative Study | Journal: PloS one | Year: 2016

The current study compared the effects of high-intensity aerobic training (HIT) and sprint interval training (SIT) on mountain biking (MTB) race simulation performance and physiological variables, including peak power output (PPO), lactate threshold (LT) and onset of blood lactate accumulation (OBLA).Sixteen mountain bikers (mean SD: age 32.1 6.4 yr, body mass 69.2 5.3 kg and VO2max 63.4 4.5 mLkg(-1)min(-1)) completed graded exercise and MTB performance tests before and after six weeks of training. The HIT (7-10 x [4-6 min--highest sustainable intensity / 4-6 min-CR100 10-15]) and SIT (8-12 x [30 s--all-out intensity / 4 min--CR100 10-15]) protocols were included in the participants regular training programs three times per week.Post-training analysis showed no significant differences between training modalities (HIT vs. SIT) in body mass, PPO, LT or OBLA (p = 0.30 to 0.94). The Cohens d effect size (ES) showed trivial to small effects on group factor (p = 0.00 to 0.56). The interaction between MTB race time and training modality was almost significant (p = 0.08), with a smaller ES in HIT vs. SIT training (ES = -0.43). A time main effect (pre- vs. post-phases) was observed in MTB race performance and in several physiological variables (p = 0.001 to 0.046). Co-variance analysis revealed that the HIT (p = 0.043) group had significantly better MTB race performance measures than the SIT group. Furthermore, magnitude-based inferences showed HIT to be of likely greater benefit (83.5%) with a lower probability of harmful effects (0.8%) compared to SIT.The results of the current study suggest that six weeks of either HIT or SIT may be effective at increasing MTB race performance; however, HIT may be a preferable strategy.ClinicalTrials.gov NCT01944865.


PubMed | Performance Laboratory
Type: Journal Article | Journal: Journal of strength and conditioning research | Year: 2011

The aim of this study was to estimate, using video analysis, what proportion of the total energy expenditure during a tennis match is accounted for by aerobic and anaerobic metabolism, respectively. The method proposed involved estimating the metabolic power (MP) of 5 activities, which are inherent to tennis: walking, running, hitting the ball, serving, and sitting down to rest. The energy expenditure concerned was calculated by sequencing the activity by video analysis. A bioenergetic model calculated the aerobic energy expenditure (EEO2mod) in terms of MP, and the anaerobic energy expenditure was calculated by subtracting this (MP - EEO2mod). Eight tennis players took part in the experiment as subjects (mean SD: age 25.2 1.9 years, weight 79.3 10.8 kg, VO2max 54.4 5.1 mlkg(-1)min(-1)). The players started off by participating in 2 games while wearing the K4b2, with their activity profile measured by the video analysis system, and then by playing a set without equipment but with video analysis. There was no significant difference between calculated and measured oxygen consumptions over the 16 games (p = 0.763), and these data were strongly related (r = 0.93, p < 0.0001). The EEO2mod was quite weak over all the games (49.4 4.8% VO2max), whereas the MP during points was up to 2 or 3 times the VO2max. Anaerobic metabolism reached 32% of the total energy expenditure across all the games 67% for points and 95% for hitting the ball. This method provided a good estimation of aerobic energy expenditure and made it possible to calculate the anaerobic energy expenditure. This could make it possible to estimate the metabolic intensity of training sessions and matches using video analysis.

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