Position specific physical performance and running intensity fluctuations in elite women's football.

The purpose of the present study was to investigate the physical performance of elite female football players during match play along with transient alterations in running performance following 1- and 5-min univariate peak periods. 54 elite female players from four top-level Norwegian teams were monitored for one season (n = 393 match observations), and physical performance data collected using STATSport GPS APEX. Results revealed significant differences in physical performance between the positions during full match play, particularly between wide and central players. Both full backs (FBs) and wide midfielders (WMs) covered more total distance (TD), high-speed running distance (HSRD), and sprint distance (SpD) than center backs (CBs) (p < 0.05-0.001), while WMs also covered more HSRD than both central midfielders (CMs) (p < 0.01) and forwards (FWs) (p < 0.05), and more acceleration -and deceleration distance (Accdist and Decdist ) than both CBs and CMs (p < 0.01-0.001). A similar pattern was observed for the peak period analysis, with FBs and WMs covering more SpD in peak 1 min than CBs and CM (p < 0.001) and more SpD in peak 5-min than CBs, CMs, and FWs (p < 0.001). Irrespective of the variable analyzed, greater distances were covered during the peak 5-min period than in the next-5 and mean 5-min periods (p < 0.001). Significant (p < 0.001), but small to trivial (Cohen's Dz : 0.07-0.20), decreases in distance covered were also observed for each variable following each univariate peak 5-min period. In conclusion, practitioners should account for differences in physical performance when developing training programs for female football players and be aware of transient reductions in physical performance following univariate peak 1- and 5-min periods. Specifically, the very high intensity in 1-min peak periods adds support to the principal of executing speed endurance activities during training to mirror and be prepared for the physical demands of match play.

Kicking Velocity and Effect on Match Performance When using a Smaller, Lighter Ball in Women's Football.

The present study evaluated the effect of a smaller, lighter ball on kicking speed and technical-tactical and physical match performance in high-level adult female footballers. In the laboratory test setting, the peak ball velocity was 6% higher with the new ball (NB) than the standard ball (SB) (26.5±0.5 vs. 25.1±0.5 m·s-1, p<0.05). However, during match-play, no differences were observed in mean heart rate (87±5 vs. 87±5%HRmax; p>0.05), blood lactate (90 min: 4.7±1.7 and 4.0±1.7 mmol·l-1; p>0.05), total distance covered (10.6±0.9 and 10.4±0.8 km; p>0.05), intense running (>16 km/h) (2.08±0.42 and 1.94±0.38 km; p>0.05) and match-induced decrement in Yo-Yo IR1 performance (28 vs. 31%, respectively, p<0.05) using NB compared to SB. Likewise, no difference was observed in the number of short, medium-range or long passes during matches played with the 2 ball types, and there was no difference in passing success rate (NB: 68±1% and SB: 68±1%, p>0.05). In conclusion, high-level adult female footballers had a higher kicking speed when using a smaller, lighter ball, but no differences were observed during match-play with the 2 ball types in respect of technical-tactical and physical match performance. The physical loading was high for the players when playing with both ball types.

Effect of high-intensity training on speed and agility performance in 10-year-old soccer players.

AIM: The aim of the present study was to assess the effect of short-burst high intensity training on speed and agility performance in 10-year-old male soccer players. METHODS: Pretest posttest experimental design. A training group (TG) (N.=20; age 10.5 SD ± 0.2), followed an 8 week intervention program, and with an corresponding control group (CG) (N.=12; age 10.4 SD ± 0.2). MAIN OUTCOME MEASURES: 10 m sprint, 20 m sprint and 20 m agility performance, and correlation between linear sprint and agility performance. Brower Timing System (USA) were used to record split and completion time. One way analysis of variance (ANOVA), two tailed paired t-test and Pearson's correlation r were used in statistical analyses. All analyses were performed using SPSS version 19.0. RESULTS: Findings from the present study showed significant improvement in agility performance (7.8%) and 20 m sprint (1.8%) (P<0.05). No significant performance increase was obtained in the CG. Furthermore the correlation between 10 m sprint and agility was r=0.40 and between 20 m sprint and agility performance r=0.58 (P<0.05). CONCLUSION: These results demonstrate that short-burst high intensity training increase speed and agility performance in 10-year-old male soccer players. The results also indicate a common variance between straight line sprinting and agility performance.

The correlation between peak oxygen uptake (VO2peak) and running performance in children and adolescents. aspects of different units.

The method of removing the confounding effect of body mass on peak oxygen uptake simply by dividing the measured values by body mass has been questioned. The aim of the study was to find an expression of body mass for compensating for differences in body mass so as to achieve the best correlation to running performance. In a cross-sectional study, design peak oxygen uptake (VO2peak) was measured in 107 boys in the age range 8-17 years and 88 girls in the age range 8-16 years. The present study indicates that VO2peak do not increase in proportion to body mass during running, rather that VO2peak is inversely related to body mass. When using allometric regression standards with the sexes separated in gender groups, there was a tendency that boys achieved scaling factors closer to unity than did the girls. The increase in subcutaneous fat in the girls throughout the pubertal years is the most likely reason why body mass increased proportionally more than VO2peak in girls. The present study indicates that VO2peak when expressed as milliliters per kilogram per minute (ml kg(-1) min(-1)) is a poor denominator for VO2peak as a function of running performance in children and adolescents.

[Physical activity and physical performance in children and adolescents]. / Fysisk aktivitet og fysisk yteevne hos barn og unge.

BACKGROUND: Research and general experience regarding the importance of physical activity in adults on various parameters such as performance ability and weight control is often extrapolated to be valid for children and adolescents. MATERIAL AND METHODS: This article is a brief review of research on physical activity level and performance ability in children and adolescents. RESULTS: Findings regarding physical activity level and physical fitness are reviewed. INTERPRETATION: The absence of reference material which goes 20-30 years back in time as well as contradictive findings on whether changes in social structure have caused a reduction in physical activity, makes it difficult to draw conclusions. The relationship between physical activity and physical fitness is not clear. Growth per se leads to methodical problems regarding whether it is the activity or maturation that cause changes in physical parameters. Contradictory results might partly be a consequence of the different methods used. An important challenge in future research on physical fitness is to establish a reference material with valid measures of physical activity levels.