scholarly journals Comparison of Energy Contributions and Workloads in Male and Female Badminton Players During Games Versus Repetitive Practices

2021 ◽  
Vol 12 ◽  
Author(s):  
Yue Fu ◽  
Yu Liu ◽  
Xiaoping Chen ◽  
Yongming Li ◽  
Bo Li ◽  
...  
Keyword(s):  
Average Rate ◽  
Energy Systems ◽  
Energy System ◽  
Substrate Oxidation ◽  
Relative Energy ◽  
Energy Contribution ◽  
Male And Female ◽  
Energy Demands ◽  
Anaerobic Energy ◽  
Daily Training

PurposeThe aim of this study was to compare the energy contributions and workloads in men and women during badminton matches versus frequently used multi-ball smash practices.MethodsFourteen badminton players performed one badminton singles game and one session of smashing practice on separate days. The energy contributions were examined in terms of each individual’s three energy systems and substrate oxidation, while workloads included heart rate (HR), Player Load (PL), accelerations, decelerations, changes of direction, and jumps.Results(1) During games, male players exhibited higher adenosine triphosphate–phosphocreatine system contribution (EPCr, kJ) (p = 0.008) and average rate of carbohydrate oxidation (RCHO, g/min) (p = 0.044) than female players, while female players showed greater absolute PL (p = 0.029) and more accelerations (p = 0.005) than male players. Furthermore, players who lost performed higher relative PL (p = 0.017) than those who won. (2) Higher energy system contributions, including EPCr (kJ) (p = 0.028), EHLa (kJ) (p = 0.024), EAer (kJ) (p = 0.012), ETot (kJ) (p = 0.007), and RCHO (g/min) (p = 0.0002), were seen in male players during repetitive spike practices. Male players also made greater number of jumps (p = 0.0002). (3) Players exhibited higher aerobic energy contribution (p < 0.001), mean HR (p = 0.002), and HRmax (p = 0.029) during games, while exhibiting greater anaerobic energy contribution (p < 0.001) and relative PL (p = 0.001) during repetitive practices.ConclusionThe similarities between male and female badminton players in proportional use of the three energy systems during games and repetitive spike training indicate similar relative energy demands for both genders. However, considering the need for higher aerobic capacity in competition, it might be advisable to design appropriate work:rest ratios for repetitive practices in daily training.

scholarly journals The Dynamics of the Anaerobic Energy Contribution During a Simulated Mass-Start Competition While Roller-Ski Skating on a Treadmill

2021 ◽  
Vol 3 ◽  
Author(s):  
Dionne A. Noordhof ◽  
Marius Lyng Danielsson ◽  
Knut Skovereng ◽  
Jørgen Danielsen ◽  
Trine M. Seeberg ◽  
...  
Keyword(s):  
Correlation Coefficients ◽  
Energy Systems ◽  
Energy System ◽  
Oxygen Deficit ◽  
Time To Exhaustion ◽  
Energy Reserves ◽  
Energy Contribution ◽  
Significant Difference ◽  
Anaerobic Energy ◽  
And Performance

The purposes of this study were: 1) to investigate the anaerobic energy contribution during a simulated cross-country (XC) skiing mass-start competition while roller-ski skating on a treadmill; 2) to investigate the relationship between the recovery of the anaerobic energy reserves and performance; and 3) to compare the gross efficiency (GE) method and maximal accumulated oxygen deficit (MAOD) to determine the anaerobic contribution. Twelve male XC skiers performed two testing days while roller skiing on a treadmill. To collect submaximal data necessary for the GE and MAOD method, participants performed a resting metabolism measurement, followed by low-intensity warm up, 12 submaximal 4-min bouts, performed using three different skating sub-techniques (G2 on a 12% incline, G3 on 5% and G4 on 2%) on three submaximal intensities on day 1. On day 2, participants performed a 21-min simulated mass-start competition on varying terrain to determine the anaerobic energy contribution. The speed was fixed, but when participants were unable to keep up, a 30-s rest bout was included. Performance was established by the time to exhaustion (TTE) during a sprint at the end of the 21-min protocol. Skiers were ranked based on the number of rest bouts needed to finish the protocol and TTE. The highest GE of day 1 for each of the different inclines/sub-techniques was used to calculate the aerobic and anaerobic contribution during the simulated mass start using the GE method and two different MAOD approaches. About 85–90% of the required energy during the simulated mass-start competition (excluding downhill segments) came from the aerobic energy system and ~10–15% from the anaerobic energy systems. Moderate to large Spearman correlation coefficients were found between recovery of anaerobic energy reserves and performance rank (rs = 0.58–0.71, p < 0.025). No significant difference in anaerobic work was found between methods/approaches (F(1.2,8.5) = 3.2, p = 0.10), while clear individual differences existed. In conclusion, about 10–15% of the required energy during the periods of active propulsion of a 21-min simulated mass-start competition came from the anaerobic energy systems. Due to the intermittent nature of XC skiing, the recovery of anaerobic energy reserves seems highly important for performance. To assess the anaerobic contribution methods should not be used interchangeably.

scholarly journals Energy System Contributions and Physical Activity in Specific Age Groups during Exergames

2020 ◽  
Vol 17 (13) ◽  
pp. 4905
Author(s):  
Seung-Bo Park ◽  
Minjun Kim ◽  
Eunseok Lee ◽  
Doowon Lee ◽  
Seong Jun Son ◽  
...  
Keyword(s):  
Physical Activity ◽  
Older Adults ◽  
Heart Rate ◽  
Oxygen Uptake ◽  
Total Energy ◽  
Body Mass ◽  
Age Groups ◽  
Energy Systems ◽  
Energy System ◽  
Energy Demands

Exergames have been recommended as alternative ways to increase the health benefits of physical exercise. However, energy system contributions (phosphagen, glycolytic, and oxidative) of exergames in specific age groups remain unclear. The purpose of this study was to investigate the contributions of three energy systems and metabolic profiles in specific age groups during exergames. Seventy-four healthy males and females participated in this study (older adults, n = 26: Age of 75.4 ± 4.4 years, body mass of 59.4 ± 8.7 kg, height of 157.2 ± 8.6 cm; adults, n = 24: Age of 27.8 ± 3.3 years, body mass of 73.4 ± 17.8 kg, height of 170.9 ± 11.9 cm; and adolescents, n = 24: Age of 14 ± 0.8 years, body mass of 71.3 ± 11.5 kg, height of 173.3 ± 5.2 cm). To evaluate the demands of different energy systems, all participants engaged in exergames named Action-Racing. Exergames protocol comprised whole-body exercises such as standing, sitting, stopping, jumping, and arm swinging. During exergames, mean heart rate (HRmean), peak heart rate (HRpeak), mean oxygen uptake (VO2mean), peak oxygen uptake (VO2peak), peak lactate (Peak La−), difference in lactate (ΔLa−), phosphagen (WPCr), glycolytic (WLa−), oxidative (WAER), and total energy demands (WTotal) were analyzed. The contribution of the oxidative energy system was higher than that of the phosphagen or glycolytic energy system (65.9 ± 12% vs. 29.5 ± 11.1% or 4.6 ± 3.3%, both p < 0.001). The contributions of the total energy demands and oxidative system in older adults were significantly lower than those in adults and adolescents (72.1 ± 28 kJ, p = 0.028; 70.3 ± 24.1 kJ, p = 0.024, respectively). The oxidative energy system was predominantly used for exergames applied in the current study. In addition, total metabolic work in older adults was lower than that in adolescents and adults. This was due to a decrease in the oxidative energy system. For future studies, quantification of intensity and volume is needed to optimize exergames. Such an approach plays a crucial role in encouraging physical activity in limited spaces.

scholarly journals The influence of urban form on the grid integration of renewable energy technologies and distributed energy systems

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
A. T. D. Perera ◽  
Silvia Coccolo ◽  
Jean-Louis Scartezzini
Keyword(s):  
Renewable Energy ◽  
Urban Form ◽  
Systems Design ◽  
Energy Systems ◽  
Building Blocks ◽  
Energy System ◽  
Urban Morphology ◽  
Urban Forms ◽  
Energy Demands ◽  
The Impact

AbstractStandard and newly designed building blocks for complex urban sites– also designated by urban archetypes - are used in this study to quantify the influence of urban forms on their energy demand and energy systems design. An energy hub, which consists on a multi-carrier energy system involving multiple energy conversion, storage and/or network technologies, is employed to quantify the impact of the urban morphology on the energy system requirements. This study reveals that urban archetypes have a notable influence on the heating and cooling energy demands of city districts that can be characterized using form factors and floor area ratio. However, the influence on demand profiles cannot be assessed based on the aforementioned indicators. The cost of energy systems can increase up to 50% due to the impact of urban forms that are well beyond the increase of peak and/or annual energy demands. In addition, renewable energy integration to the grid as well its utilization in districts is influenced by urban forms. This makes it essential to consider energy system design as a part of the urban planning process moving even beyond building simulation.

Method-Induced Differences of Energy Contributions in Women’s Kayaking

2018 ◽  
Vol 13 (1) ◽  
pp. 9-13
Author(s):  
Yongming Li ◽  
Margot Niessen ◽  
Xiaoping Chen ◽  
Ulrich Hartmann
Keyword(s):  
Relative Energy ◽  
Oxygen Deficit ◽  
Energy Calculation ◽  
Longitudinal Assessment ◽  
Energy Contribution ◽  
Training Experience ◽  
Incremental Exercise Test ◽  
Accumulated Oxygen Deficit ◽  
Anaerobic Energy ◽  
Gas Metabolism

Context: Different relative aerobic energy contribution (WAER%) has been reported for the 2 women’s Olympic kayaking disciplines (ie, 200 and 500 m). Purpose: To investigate whether the adopted method of energy calculation influences the value of WAER% during kayaking time trials. Methods: Eleven adolescent female kayakers (age 14 ± 1 y, height 172 ± 4 cm, body mass 65.4 ± 4.2 kg, VO2peak 42.6 ± 4.9 mL·min−1·kg−1, training experience 1.5 ± 0.3 y) volunteered to participate in 1 incremental exercise test and 2 time trials (40 and 120 s) on the kayak ergometer. A portable spirometric system was used to measure gas metabolism. Capillary blood was taken from the ear lobe during and after the tests and analyzed for lactate afterward. The method of modified maximal accumulated oxygen deficit (m-MAOD) and the method based on the fast component of oxygen-uptake off-kinetics (PCr-La-O2) were used to calculate the energy contributions. Results: The anaerobic energy portions from m-MAOD were lower than those from PCr-La-O2 in the 40-s (41.9 ± 8.8 vs 52.8 ± 4.0 kJ, P > .05) and 120-s (64.1 ± 27.9 vs 68.2 ± 10.0 kJ, P > .05) time trials, which induced differences of WAER% between m-MAOD and PCr-La-O2 (36.0% vs 30.0% in 40 s, P > .05; 60.9% vs 57.5% in 120 s, P > .05). Conclusions: The reported different WAER% in women’s Olympic kayaking could be partly attributed to the adopted method of energy calculation (ie, m-MAOD vs PCr-La-O2). A fixed method of energy calculation is recommended during the longitudinal assessment on the relative energy contribution in women’s Olympic kayaking.

scholarly journals Aerobic Energy Contribution during High Intensity Exercise

2004 ◽  
Vol 10 (2) ◽  
pp. 15-21
Author(s):  
Michael CHIA
Keyword(s):  
Oxygen Uptake ◽  
High Intensity ◽  
Maximal Exercise ◽  
Mechanical Efficiency ◽  
Peak Oxygen Uptake ◽  
Energy Contribution ◽  
Research Attention ◽  
Energy Demands ◽  
Anaerobic Energy ◽  
Energy Supplementation

LANGUAGE NOTE | Document text in English; abstract also in Chinese.The review focuses on the aerobic energy contribution during high intensity cycling exercise. It is erroneous to assume that the energy demands of an exercise task can be met exclusively by either aerobic or anaerobic sources. During peak oxygen uptake determination, especially during the latter portions of the incremental exercise test, the anaerobic energy stores are also taxed. Not surprising, during maximal exercise of a short duration, there is also energy supplementation from aerobic energy sources. However, for a test to be considered predominantly anaerobic, the aerobic contribution to the test must be kept minimal. The quantification of aerobic contribution to a maximal exercise performance is difficult because the mechanical efficiency (ME) during a non-steady state exercise task remains speculative. Nevertheless extreme ME values for cycling have been proposed to provide a general scope of the estimated values. In adults, assumptions about oxygen uptake lag time, the size and role of the stored oxygen stores, which are taken into account also affect the magnitude to the aerobic contribution. Equivalent data on young people are insecure and greater research attention in this area is advised.本文著重介紹了大強度自行車運動中的有氧供能。如果認為運動中機體所需能量僅以某一能源系統，有氧系統或無氧系統供能是不正確的。在逐級遞增負荷測定最大攝氧量的運動中，尤其在測試的後階段，無氧系統參與供能。而在短時間的最大強度運動中，有氧供能也佔有一定的比例。即使進行無氧運動，在測試中仍能發現有低比例有氧供能。很難確定有氧系統在最大強度運動中的供能量為多少，因為不穩定狀態下的運動其供能效率仍不十分明確。但對於踏車運動中最高供能效率有一估計值範圍。對於成年人，攝氧量的延遲時間以及氧的儲存量的多少將影響最大有氧供能的比例。而在青少年中：有關這方面的資料較為缺乏，有待進一步的研究。

scholarly journals Dynamic Modelling of LNG Powered Combined Energy Systems in Port Areas

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3640
Author(s):  
Davide Borelli ◽  
Francesco Devia ◽  
Corrado Schenone ◽  
Federico Silenzi ◽  
Luca A. Tagliafico
Keyword(s):  
Energy Savings ◽  
Ghg Emissions ◽  
Dynamic Modelling ◽  
Energy Systems ◽  
Energy System ◽  
Primary Energy ◽  
Time Behavior ◽  
Vapor Compression Refrigeration Cycle ◽  
Integrated Energy System ◽  
Energy Share

Liquefied Natural Gas (LNG) is a crucial resource to reduce the environmental impact of fossil-fueled vehicles, especially with regards to maritime transport, where LNG is increasingly used for ship bunkering. The present paper gives insights on how the installation of LNG tanks inside harbors can be capitalized to increase the energy efficiency of port cities and reduce GHG emissions. To this purpose, a novel integrated energy system is introduced. The Boil Off Gas (BOG) from LNG tanks is exploited in a combined plant, where heat and power are produced by a regenerated gas turbine cycle; at the same time, cold exergy from LNG regasification contributes to an increase in the efficiency of a vapor compression refrigeration cycle. In the paper, the integrated energy system is simulated by means of dynamic modeling under daily variable working conditions. Results confirm that the model is stable and able to determine the time behavior of the integrated plant. Energy saving is evaluated, and daily trends of key thermophysical parameters are reported and discussed. The analysis of thermal recovering from the flue gases shows that it is possible to recover a large energy share from the turbine exhausts. Hence, the system can generate electricity for port cold ironing and, through a secondary brine loop, cold exergy for a refrigeration plant. Overall, the proposed solution allows primary energy savings up to 22% when compared with equivalent standard technologies with the same final user needs. The exploitation of an LNG regasification process through smart integration of energy systems and implementation of efficient energy grids can contribute to greener energy management in harbors.

scholarly journals Evaluation of the energy demands for a floating O&M-hub

2021 ◽  
Author(s):  
F. Wittmann ◽  
C. Schmitt ◽  
F. Adam ◽  
P. Dierken
Keyword(s):  
Software Tool ◽  
Energy System ◽  
Spare Parts ◽  
Simulation Software ◽  
Offshore Wind ◽  
Baseline Scenario ◽  
Horizon 2020 ◽  
Energy Supply System ◽  
The North ◽  
Energy Demands

AbstractThe Energyhub@Sea concept is one of the four research applications of the Space@Sea project funded by the EU’s Horizon 2020 research program (GA number: 774253). The focus of this paper is the evaluation of the energy demands of an energy self-sufficient maintenance platform at the location of Helgoland in the North Sea. In view of this, a standardized modular floater was developed as an offshore wind operation and maintenance base, which in the following paper is referred to as an O&M hub. The O&M hub is intended to be equipped with accommodation facilities and various renewable energy infrastructure as well as spare parts logistics, enabling the platform to perform maintenance of offshore gearless wind turbines with a capacity of up to 10 MW. To be energy self-sustaining, an energy supply system for the hub was developed and simulated at a resolution of ten minutes by means of the Top-Energy simulation software, a commercial software tool. As a basis for the simulation, an approach for the automated determination of flexible load profiles, in resolutions of up to ten minutes was developed. This load profile generator creates load profiles on the basis of environmental conditions, technical characteristics, and expected behaviors of the inhabitants. On the basis of the generated load profiles, a first layout (referred to as baseline scenario) for the different components of the energy system was evaluated and tested through simulation. In a second step, three optimization scenarios were developed and simulated with regards to the financial feasibility of the Energyhub.

scholarly journals Accessibility and Sustainability of Hybrid Energy Systems for a Cement Factory in Oman

2020 ◽  
Vol 13 (1) ◽  
pp. 93
Author(s):  
Wesam H. Beitelmal ◽  
Paul C. Okonkwo ◽  
Fadhil Al Housni ◽  
Wael Alruqi ◽  
Omar Alruwaythi
Keyword(s):  
Functional Limitations ◽  
Energy Systems ◽  
Energy System ◽  
Electricity Production ◽  
Diesel Generator ◽  
Hybrid Energy ◽  
Electric System ◽  
Cement Factory ◽  
Hybrid Energy Systems ◽  
Cost Of Energy

Diesel generators are being used as a source of electricity in different parts of the world. Because of the significant expense in diesels cost and the requirement for a greener domain, such electric generating systems appear not to be efficient and environmentally friendly and should be tended to. This paper explores the attainability of utilizing a sustainable power source based on a cross-breed electric system in the cement factory in Salalah, Oman. The HOMER software that breaks down the system setup was utilized to examine the application and functional limitations of each hybridized plan. The result showed that a renewable-energy (RE)-based system has a lower cost of energy (COE) and net present cost (NPC) compared to diesel generator-based hybrid electric and standalone systems. Although the two pure renewable hybrid energy systems considered in this study displayed evidence of no emissions, lower NPC and COE values are observed in the photovoltaic/battery (PV/B) hybrid energy system compared with photovoltaic/wind turbine/battery (PV/WT/B). The PV/WT/B and PV/B systems have higher electricity production and low NPC and COE values. Moreover, the PV/B has the highest return on investment (ROI) and internal rate of return (IRR), making the system the most economically viable and adjudged to be a better candidate for rural community electrification demands.

Developing an Integrated Energy System Interface for Electricity-Hydrogen Hybrid Nuclear Operations

2020 ◽  
Vol 64 (1) ◽  
pp. 92-96
Author(s):  
Thomas A. Ulrich ◽  
Roger Lew ◽  
Ronald L. Boring ◽  
Torrey Mortenson ◽  
Jooyoung Park ◽  
...  
Keyword(s):  
Human Factors ◽  
Electricity Markets ◽  
Nuclear Power ◽  
Power Plants ◽  
Energy Systems ◽  
Energy System ◽  
Human Factors Engineering ◽  
Engineering Project ◽  
Early Integration ◽  
Integrated Energy Systems

Nuclear power plants are looking towards integrated energy systems to address the challenges faced by increasing competition from renewable energy and cheap natural gas in wholesale electricity markets. Electricity-hydrogen hybrid operations is one potential technology being explored. As part of this investigation a human factors team was integrated into the overall engineering project to develop a human system interface (HSI) for a novel system to extract steam for a coupled hydrogen production process. This paper presents the process used to perform the nuclear specific human factors engineering required to develop the HSI for this novel and unprecedented system. Furthermore, the early integration of the human factors team and the meaningful improvements to the engineering of the system itself in addition to the successful development of the HSI for this particular application are described. Lastly, the HSI developed is presented to demonstrate the culmination of the process and disseminate a potential HSI design for electricity-hydrogen hybrid operations that may be useful for others exploring similar integrated energy systems concepts.

scholarly journals Dynamic Stability Enhancement of a Hybrid Renewable Energy System in Stand-Alone Applications

Computation ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 14
Author(s):  
Ezzeddine Touti ◽  
Hossem Zayed ◽  
Remus Pusca ◽  
Raphael Romary
Keyword(s):  
Renewable Energy ◽  
Energy Systems ◽  
Experimental Tests ◽  
Energy System ◽  
Induction Generator ◽  
Technical Solution ◽  
Hybrid Energy ◽  
Wind Speeds ◽  
Hybrid Renewable Energy System ◽  
Stability Enhancement

Renewable energy systems have been extensively developed and they are attractive to become widespread in the future because they can deliver energy at a competitive price and generally do not cause environmental pollution. However, stand-alone energy systems may not be practical for satisfying the electric load demands, especially in places having unsteady wind speeds with high unpredictability. Hybrid energy systems seem to be a more economically feasible alternative to satisfy the energy demands of several isolated clients worldwide. The combination of these systems makes it possible to guarantee the power stability, efficiency, and reliability. The aim of this paper is to present a comprehensive analysis and to propose a technical solution to integrate a self-excited induction generator in a low power multisource system. Therefore, to avoid the voltage collapsing and the machine demagnetization, the various parameters have to be identified. This procedure allows for the limitation of a safe operating area where the best stability of the machine can be obtained. Hence, the load variation interval is determined. An improvement of the induction generator stability will be analyzed. Simulation results will be validated through experimental tests.

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