Framework for Electric Vehicles and Photovoltaic Synergies

Historically road transport has been exclusively dominated by petrol and diesel engines. Both alternatives are proved to be unsustainable due to their environmental impacts and the limited nature of their primary resources. Today’s transportation sector in the European Union (EU) accounts for 23% of CO2 emissions, 72% of which is being emitted by road transport. The European Union’s CO2 emission regulation for new cars, has come as a response to set emission performance limits for new passenger cars with the goal of establishing a road map change for automotive sector. Furthermore, the EU has set challenging targets to reduce greenhouse gas emissions by 40% in 2030 (relative to emissions in 1990) and for energy consumed to be generated at least with 27% from renewable sources in 2030. As regards energy efficiency, the 2030 framework also indicated that the cost-effective delivery of the greenhouse gas emissions reduction target for 2030 would require increased energy savings of the order of 27%. The renewable energy directive particularly identified: technological innovation, energy efficiency and contribution of renewable energy sources in transport sector as one of the most effective tools in reaching the expected targets in terms of sustainability and security of the supply. In such context it is obvious that reaching these challenges will be certainly depending on the rollout of Electric Vehicles (EV) as a mean of sustainable transport, higher penetration of distributed renewable energy sources. One consequential challenge will consist in accommodating such paradigm in the most cost-efficient fashion through active involvement of customer and better flexibility of the demand. This report highlights the current trends and expected evolution in the EU in term of electromobility, Photovoltaic (PV) systems and smart grids, with the aim of identifying mutual synergies aiming at enabling: energy efficiency, sustainable transport and higher share of renewable energy sources in the final energy mix. A technical conceptual architecture for integration of EV facilities and distributed generation sources in the context of smart grid is proposed to identify the predictable penetration limits of PV systems and EV users.JRC.F.3-Energy Security, Systems and Marke

Combination of Agility and Plyometric Training Provides Similar Training Benefits as Combined Balance and Plyometric Training in Young Soccer Players

Introduction: Studies that combined balance and resistance training induced larger performance improvements compared with single mode training. Agility exercises contain more dynamic and sport-specific movements compared with balance training. Thus, the purpose of this study was to contrast the effects of combined balance and plyometric training with combined agility and plyometric training and an active control on physical fitness in youth.Methods: Fifty-seven male soccer players aged 10–12 years participated in an 8-week training program (2 × week). They were randomly assigned to a balance-plyometric (BPT: n = 21), agility-plyometric (APT: n = 20) or control group (n = 16). Measures included proxies of muscle power [countermovement jump (CMJ), triple-hop-test (THT)], muscle strength [reactive strength index (RSI), maximum voluntary isometric contraction (MVIC) of handgrip, back extensors, knee extensors], agility [4-m × 9-m shuttle run, Illinois change of direction test (ICODT) with and without the ball], balance (Standing Stork, Y-Balance), and speed (10–30 m sprints).Results: Significant time × group interactions were found for CMJ, hand grip MVIC force, ICODT without a ball, agility (4 m × 9 m), standing stork balance, Y-balance, 10 and 30-m sprint. The APT pre- to post-test measures displayed large ES improvements for hand grip MVIC force, ICODT without a ball, agility test, CMJ, standing stork balance test, Y-balance test but only moderate ES improvements with the 10 and 30 m sprints. The BPT group showed small (30 m sprint), moderate (hand grip MVIC, ICODTwithout a ball) and large ES [agility (4 m × 9 m) test, CMJ, standing stork balance test, Y-balance] improvements, respectively.Conclusion: In conclusion, both training groups provided significant improvements in all measures. It is recommended that youth incorporate balance exercises into their training and progress to agility with their strength and power training

THE BALTIC POWER SYSTEM BETWEEN EAST AND WEST INTERCONNECTIONS

Due to historical and geographical reasons, the Baltic States are strongly connected to the power (electricity) transmission grids of Russia and Belarus. Current energy security and energy independence targets in the EU trigger seeking for alternative power sources for the Baltic. Knowing that, a power system model of the Baltic States has been developed and validated with the purpose of providing comparative options for a reliable and secure development of the Baltic electricity system. The analysis of horizon 2020 and 2030 showed that the dependency of Baltic States on the outside resources is fairly low, provided that the expansion of the electricity system goes as planned.JRC.F.3-Energy Security, Systems and Marke

Evidence of nonlocal muscle fatigue in male youth

Evidence for nonlocal muscle fatigue (NLMF) has been inconsistent in adults, with no studies investigating youth. The objective was to examine NLMF in youth. Forty-two young males (age, 10–13 years) were tested for maximal voluntary isometric contraction (MVIC) force of the ipsilateral and contralateral knee extensors at 90° and 120° knee flexion, elbow flexors at 90°, handgrip, knee extensor isokinetic torque (300°·s −1 analyzed at 90° and 120° knee flexion), as well as a unilateral countermovement jump (CMJ) and Y Balance test (YBT). Isokinetic fatigue group (n = 15) had unilateral fatigue induced with 10 sets of 20 repetitions of maximal isokinetic knee extensor contractions at 300°·s −1 . Isometric fatigue group (n = 15) used 10 repetitions of 6-s knee extensor MVIC whereas the control group (n = 12) were not fatigued. There was no significant difference in the response to the isometric- or isokinetic-fatigue intervention protocols. Main time effects indicated that NLMF was evident with the contralateral knee extensor MVIC at 90° (p = 0.008; 8.9%), knee extensor isokinetic torque at 90° (p < 0.001; 11.4%), and 120° (p = 0.05; 5.4%), CMJ (p = 0.02; 11.5%), handgrip (p = 0.06; 4.5%), elbow flexors (p < 0.001; 7.7%), and YBT (p = 0.001; 5.6%). Ipsilateral NLMF deficits occurred with handgrip (p < 0.001; 7.3%), elbow flexors MVICs (p < 0.001; 10.7%), CMJ (p = 0.02; 12.2%), and YBT (p = 0.002; 3.8%). NLMF with similar relative fatigue-induced deficits of fatigued and nonfatigued limbs suggest that youth fatigue is highly dependent upon the extent of activation or inhibition of the nervous system. Coaches of young athletes might consider developing technical motor skills before fatiguing exercise components, which might hinder the proficiency of their performance

EVIDENCE OF HOMOLOGOUS AND HETEROLOGOUS EFFECTS AFTER UNILATERAL LEG TRAINING IN YOUTH

The positive effects of unilateral training on contralateral muscles (cross education) has been demonstrated with adults for over a century. There is limited evidence for cross education of heterologous muscles. Cross education has not been demonstrated with children. It was the objective of this study to investigate cross education training in children examining ipsilateral and contralateral homologous and heterologous muscles. Forty-eight male children (10-13 years) were assessed for unilateral, ipsilateral and contralateral lower limb strength, power and endurance (1 repetition maximum (RM) leg press, knee extensors (KE) and flexors (KF) maximum voluntary isometric contractions (MVIC), countermovement jump (CMJ), muscle endurance test (leg press repetitions with 60% 1RM)), and upper body unilateral MVIC elbow flexors (EF) and handgrip strength. An eight-week training program involved two unilateral leg press resistance training groups (high load-low repetitions: 4-8 sets of 5RM, and low load-high repetitions:1-2 sets of 20RM) and control (untrained) group. All muscles exhibited improvements of 6.1% to 89.1%. The trained limb exhibited greater adaptations than the untrained limb for leg press 1RM (40.3% vs. 25.2%; p=0.005), and 60% 1RM leg press (104.1% vs. 73.4%; p=0.0001). The high load-low repetition training induced (pThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Dominant and nondominant leg press training induce similar contralateral and ipsilateral limb training adaptations with children

International audienceCross-education has been extensively investigated with adults. Adult studies report asymmetrical cross-education adaptations predominately after dominant limb training. The objective of the study was to examine unilateral leg press (LP) training of the dominant or nondominant leg on contralateral and ipsilateral strength and balance measures. Forty-two youth (10-13 years) were placed (random allocation) into a dominant (n = 15) or nondominant (n = 14) leg press training group or nontraining control (n = 13). Experimental groups trained 3 times per week for 8 weeks and were tested pre-/post-training for ipsilateral and contralateral 1-repetition maximum (RM) horizontal LP, maximum voluntary isometric contraction (MVIC) of knee extensors (KE) and flexors (KF), countermovement jump (CMJ), triple hop test (THT), MVIC strength of elbow flexors (EF) and handgrip, as well as the stork and Y balance tests. Both dominant and nondominant LP training significantly (p < 0.05) increased both ipsilateral and contralateral lower body strength (LP 1RM (dominant 59.6%-81.8%; nondominant 59.5%-96.3%), KE MVIC (dominant 12.4%-18.3%; nondominant 8.6%-18.6%), KF MVIC (dominant 7.9%-22.3%; nondominant nonsignificant-3.8%), and power (CMJ dominant 11.1%-18.1%; nondominant 7.7%-16.6%)). The exception was that nondominant LP training demonstrated a nonsignificant change with the contralateral KF MVIC. Other significant improvements were with nondominant LP training on ipsilateral EF 1RM (6.2%) and THT (9.6%). There were no significant changes with EF and handgrip MVIC. The contralateral leg stork balance test was impaired following dominant LP training. KF MVIC exhibited the only significant relative post-training to pretraining (post-test/pre-test) ratio differences between dominant versus nondominant LP cross-education training effects. In conclusion, children exhibit symmetrical cross-education or global training adaptations with unilateral training of dominant or nondominant upper leg

Comparison of Cross-Education and Global Training Effects in Adults and Youth After Unilateral Strength Training

International audienceChaouachi, A, Ben Othman, A, Chaouachi, M, Hechmi, A, Farthing, JP, Granacher, U, and Behm, DG. Comparison of cross-education and global training effects in adults and youth after unilateral strength training. J Strength Cond Res 36(8): 2121-2131, 2022-Youth strength training research examining contralateral, homologous (cross-education), and heterologous (global training) effects after unilateral training have provided mixed results and the relationship to adults has not been compared. The objective was to compare adult and youth cross-education and global training effects on dominant and nondominant limb testing. Initially, 15 men and 15 prepubertal boys volunteered for each unilateral chest press (CP), handgrip training, and control groups (n = 89). Individuals trained their dominant limb 3 times per week for 8 weeks and had their dominant and nondominant limbs tested for CP and leg press 1 repetition maximum (1RM), handgrip, knee extension and flexion, and elbow extension and flexion maximum voluntary isometric contractions (MVICs). Adult CP training gains were significantly greater than youth with lower-body testing (p = 0.002-0.06), whereas youth CP training gains exceeded adults with upper-body tests (p = 0.03-0.07). Training specificity was evident with greater CP 1RM increases with CP vs. handgrip training for both youth (p &lt; 0.0001) and adults (p &lt; 0.0001). Handgrip training elicited greater gains in handgrip MVICs compared with other strength tests (p &lt; 0.0001). In conclusion, only contralateral CP 1RM showed a training advantage for unilateral CP over unilateral handgrip training. Adults showed greater gains with lower-body testing, whereas youth showed greater gains with upper-body testing

The combination of plyometric and balance training improves sprint and shuttle run performances more often than plyometric-only training with children

Because balance is not fully developed in children and studies have shown functional improvements with balance only training studies, a combination of plyometric and balance activities might enhance static balance, dynamic balance, and power. The objective of this study was to compare the effectiveness of plyometric only (PLYO) with balance and plyometric (COMBINED) training on balance and power measures in children. Before and after an 8-week training period, testing assessed lower-body strength (1 repetition maximum leg press), power (horizontal and vertical jumps, triple hop for distance, reactive strength, and leg stiffness), running speed (10-m and 30-m sprint), static and dynamic balance (Standing Stork Test and Star Excursion Balance Test), and agility (shuttle run). Subjects were randomly divided into 2 training groups (PLYO [n = 14] and COMBINED [n = 14]) and a control group (n = 12). Results based on magnitude-based inferences and precision of estimation indicated that the COMBINED training group was considered likely to be superior to the PLYO group in leg stiffness (d = 0.69, 91% likely), 10-m sprint (d = 0.57, 84% likely), and shuttle run (d = 0.52, 80% likely). The difference between the groups was unclear in 8 of the 11 dependent variables. COMBINED training enhanced activities such as 10-m sprints and shuttle runs to a greater degree. COMBINED training could be an important consideration for reducing the high velocity impacts of PLYO training. This reduction in stretch-shortening cycle stress on neuromuscular system with the replacement of balance and landing exercises might help to alleviate the overtraining effects of excessive repetitive high load activities

Unilateral static and dynamic hamstrings stretching increases contralateral hip flexion range of motion

Static (SS) and dynamic stretching (DS) can lead to subsequent performance impairments or enhancement with the stretched limb. Crossover or non-local muscle fatigue (NLMF) refers to unilateral fatigue-induced impairments in a contralateral or non-exercised muscle. Whereas there are conflicting findings in the NLMF literature, there are few studies examining the effect of an acute bout of SS or DS on contralateral flexibility, torque or power. Fourteen highly trained subjects (means ± standard deviations: 18 ± 2 years; 179·4 ± 4·6 cm; 70·5 ± 6·3 kg; %body fat: 10·7 ± 2·5%) were tested before and following separate sessions of eight repetitions of 30 s of unilateral hip flexion SS or DS. Pre- and postintervention testing at 1 and 10 min included hip flexor range of motion (ROM), isokinetic leg flexion torque and power at 60°.s(-1) and 300°.s(-1) of the stretched and contralateral limbs. The stretched limb had a 6·3% (P = 0·01; ES: 0·91) ROM increase with DS at 10 min. The contralateral non-stretched hip flexors experienced ROM increases with SS of 5·7% (P = 0·02; ES: 0·68) from pretest to 1 min post-test, whereas DS showed 7·1% (P<0·0001; ES: 1·09) and 8·4% (P = 0·005; ES: 0·89) increases, respectively. There were no relative differences in ROM changes between conditions or limbs nor any stretch-induced changes in isokinetic torque or power. In conclusion, unilateral SS and DS augment contralateral limb ROM likely through an increased stretch tolerance