A new peak-power estimation equations in 12 to 14 years-old soccer players

This study examined the efficacy of peak-power estimation equations in children using force platform data and determined whether allometric modeling offers a sounder alternative to estimating peak power in pediatric samples. Ninety one boys and girls aged 12–16 years performed 3 countermovement jumps (CMJ) on a force platform. Estimated peak power (PPest) was determined using the Harman et al., Sayers SJ, Sayers CMJ, and Canavan and Vescovi equations. All 4 equations were associated with actual peak power (r = 0.893−0.909, all p < .01). There were significant differences between PPest using the Harman et al., Sayers SJ, and Sayers CMJ equations (p < .05) and actual peak power (PPactual). ANCOVA also indicated sex and age effect for PPactual (p < .01). Following a random two-thirds to one-third split of participants, an additive linear model (p = .0001) predicted PPactual (adjusted R2 = .866) from body mass and CMJ height in the two-thirds split (n = 60). An allometric model using CMJ height, body mass, and age was then developed with this sample, which predicted 88.8% of the variance in PPactual (p < .0001, adjusted R2 = .888). The regression equations were cross-validated using the one-third split sample (n = 31), evidencing a significant positive relationship (r = .910, p = .001) and no significant difference (p = .151) between PPactual and PPest using this equation. The allometric and linear models determined from this study provide accurate models to estimate peak power in children.

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Impact of COVID-19 Lockdown on Serie A Soccer Players’ Physical Qualities

International Journal of Sports Medicine ◽

10.1055/a-1345-9262 ◽

2021 ◽

Author(s):

Ermanno Rampinini ◽

Federico Donghi ◽

Marco Martin ◽

Andrea Bosio ◽

Marco Riggio ◽

...

Keyword(s):

Aerobic Fitness ◽

Mixed Models ◽

Peak Power ◽

Vertical Jump ◽

Soccer Players ◽

Limited Evidence ◽

Professional Soccer ◽

Home Based ◽

Before And After ◽

Different Seasons

AbstractIn March 2020, the COVID-19 pandemic forced most activities in Italy, including soccer, to cease. During lockdown, players could only train at home, with limited evidence regarding the effect of this period. Therefore, this study aimed to investigate the effect of COVID-19 lockdown on professional soccer players’ physical performance. Aerobic fitness and vertical jump were assessed before and after four periods in two different seasons: COVID-19 lockdown, competitive period before lockdown, competitive period and summer break of the 2016–2017 season. Linear mixed models were used to examine within-period changes and between-period differences in changes observed during COVID-19 lockdown and the three other periods. Within-period changes in aerobic fitness showed a significant improvement following COVID-19 lockdown (p<0.001) and a significant decline during summer break (p<0.001). Between-period differences were significant in the comparison of COVID-19 lockdown with both the competitive 2019–2020 season (p<0.01) and summer break (p<0.001). For the vertical jump, only the between-period comparison revealed significant differences as the changes associated with COVID-19 lockdown were worse than those of the two competitive periods, for both absolute (p<0.05; p<0.001) and relative peak power (p<0.01; p<0.001). Home-based training during lockdown was effective to improve aerobic fitness, although it did not allow players to maintain their competitive period’s power levels.

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Functionally valid gate-level peak power estimation for processors

2009 10th International Symposium on Quality of Electronic Design ◽

10.1109/isqed.2009.4810387 ◽

2009 ◽

Cited By ~ 5

Author(s):

Sriram Sambamurthy ◽

Sankar Gurumurthy ◽

Ramtilak Vemu ◽

Jacob A. Abraham

Keyword(s):

Peak Power ◽

Power Estimation

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Peak power estimation using genetic spot optimization for large VLSI circuits

Proceedings of the conference on Design, automation and test in Europe - DATE '99 ◽

10.1145/307418.307484 ◽

1999 ◽

Cited By ~ 9

Author(s):

Michael S. Hsiao

Keyword(s):

Peak Power ◽

Power Estimation ◽

Vlsi Circuits

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Eccentric-Overload Production during the Flywheel Squat Exercise in Young Soccer Players: Implications for Injury Prevention

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17103671 ◽

2020 ◽

Vol 17 (10) ◽

pp. 3671

Author(s):

Javier Raya-González ◽

Daniel Castillo ◽

Marta Domínguez-Díez ◽

José Luis Hernández-Davó

Keyword(s):

Injury Prevention ◽

Peak Power ◽

Power Production ◽

The Other ◽

Soccer Players ◽

Other Hand ◽

Squat Exercise ◽

Resistance Exercises ◽

Eccentric Overload

This study aimed to evaluate the differences in power production between movement phases (i.e., concentric and eccentric) during the execution of resistance exercises with a flywheel device, differentiating between execution regimes (i.e., bilateral, unilateral dominant leg and unilateral non-dominant leg). Twenty young elite soccer players (U−17) performed two sets of six repetitions of the bilateral half-squat (inertia 0.025 kg·m−2) and the lateral-squat exercise (inertia 0.010 kg·m−2) on a flywheel device. During the testing sessions, mean and peak power in concentric (MPcon) and eccentric (MPecc) phases were recorded. The non-dominant leg showed higher values in all power variables measured, although substantial differences were only found in MPecc (ES = 0.40, likely) and PPcon (ES = 0.36, possibly). On the other hand, for both exercises, MPcon was higher than MPecc (ES = −0.57 to −0.31, possibly/likely greater), while only PPecc was higher than PPcon in the dominant lateral-squat (ES = 0.44, likely). These findings suggest that young soccer players have difficulty in reaching eccentric-overload during flywheel exercises, achieving it only with the dominant leg. Therefore, coaches should propose precise preventive programs based on flywheel devices, attending to the specific characteristics of each limb, as well as managing other variables to elicit eccentric-overload.

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Relationship between Nutrition Knowledge and Physical Fitness in Semiprofessional Soccer Players

Scientifica ◽

10.1155/2014/180353 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 4

Author(s):

P. T. Nikolaidis ◽

E. Theodoropoulou

Keyword(s):

Physical Fitness ◽

Nutrition Education ◽

Peak Power ◽

Sport Performance ◽

Nutrition Knowledge ◽

Fat Free Mass ◽

Soccer Players ◽

Mean Power ◽

Wingate Anaerobic Test ◽

Knowledge Questionnaire

Whereas nutrition has a crucial role on sport performance, it is not clear to what extent nutrition knowledge is associated with physical fitness. The aim of this study was to examine the current level of nutrition knowledge of soccer players and whether this level is associated with physical fitness. Soccer players (n=185, aged21.3±4.9 yr, weight72.3±8.4 kg, and height177.5±6.4 cm) performed a battery of physical fitness tests (sit-and-reach test, SAR; physical working capacity in heart rate 170, PWC170; and Wingate anaerobic test, WAnT) and completed an 11-item nutrition knowledge questionnaire (NKQ). Low to moderate Pearson correlations (0.15<r<0.34,p<0.05) of NKQ with age, weight, height, fat free mass (FFM), SAR, peak power, and mean power of WAnT were observed. Soccer players with high score in NKQ were older (4.4 yr (2.2; 6.6), mean difference (95% confidence intervals)) and heavier (4.5 kg (0.6; 8.3)) with higher FFM (4.0 kg (1.1; 6.8)) and peak power (59 W (2; 116)) than their counterparts with low score. The moderate score in the NKQ suggests that soccer players should be targeted for nutrition education. Although the association between NKQ and physical fitness was low to moderate, there were indications that better nutrition knowledge might result in higher physical fitness and, consequently, soccer performance.

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