Physical qualities and body composition predictors of running performance in national level women's official soccer matches.

The purpose of the study was to (1) determine match running performance, anthropometry and various physical qualities of national level women soccer players and (2) identify key physical qualities and anthropometric predictors of match running profile during a competitive season. Twenty-five national level Finnish soccer players participated in the study. Players performed countermovement jump, loaded squat jumps, 30-meter sprint, maximum isokinetic knee flexor and extensor contractions, an incremental treadmill test and underwent body composition assessment in the lab. Match running performance was analyzed from 115 match observations during competitive league matches over 11 weeks after the laboratory tests. Pearson's correlation was used to determine bivariate relationships between match running variables and physical qualities and anthropometric variables. Identified significant bivariate relationships were then entered into multiple regression analyses to identify the best predictors of match running performance. Physical qualities and anthropometric variables predicted 65% of very high-intensity (VHIR) (> 19 km/h) and 63% of high-intensity (HIR) (13-19 km/h) running distances covered during matches, but only 22% of low-intensity (LIR) and 43% of total distances. Body fat percentage and high-speed knee flexor concentric strength were the most important predictors to VHIR and HIR while aerobic capacity-related variables were most important predictors to LIR and total distance. Physical qualities and anthropometry can predict a large portion of players' VHIR and HIR performance during matches in women's national level soccer. To increase player's VHIR and HIR distance, coaches could aim to develop players' high-speed (especially knee flexor concentric) strength and optimize player's body composition.

The Effect of Paddle Stroke Variables Measured by Trainesense SmartPaddle® on the Velocity of the Kayak.

(1) Background: This study aimed to compare key variables of paddle stroke measured by a commercial Trainesense SmartPaddle® against the strain-gauge shaft and investigate how these variables are associated with the velocity of the boat among national-level canoe polo players. (2) Methods: This study involved 14 Finnish national-level canoe polo players. The measurement protocol consisted of three different paddling velocities, which were performed in indoor swimming pools. The velocity of the boat was calculated based on the performance time measured with the laser photocell gate. Canoe polo equipment was used in the study and a SmartPaddle sensor was attached to the paddle blade. A strain-gauge paddle shaft was used as a reference method to examine the validity of SmartPaddle. (3) Results: The stroke rate, force production time, mean and maximal force measured with the strain-gauge paddle shaft correlated strongly (r = 0.84-0.95, p < 0.01) with SmartPaddle. However, the SmartPaddle overestimated the maximum force compared to the strain-gauge shaft. Stroke rate (r = 0.86, p < 0.01), mean force (r = 0.79, p < 0.01), maximal force (r = 0.78, p < 0.01) and total absolute impulse (r = 0.70, p < 0.01) correlated positively and force production time negatively (r = -0.76, p < 0.01) with the velocity of the boat. (4) Conclusions: We conclude that the SmartPaddle provides promising information on stroke key variables when compared to the strain-gauge paddle shaft. The SmartPaddle is a new and interesting tool for biomechanical research and daily kayaking coaching in real open water conditions. However, more research and algorithm development are needed before the SmartPaddle can be used in everyday coaching sessions in kayaking.

Changes in body composition, hormonal status, and physical fitness in 11-, 13-, and 15-year-old Finnish regional youth soccer players during a two-year follow-up.

Vänttinen, T, Blomqvist, M, Nyman, K, and Häkkinen, K. Changes in body composition, hormonal status, and physical fitness in 11-, 13-, and 15-year-old Finnish regional youth soccer players during a two-year follow-up. J Strength Cond Res 25(12): 3342-3351, 2011-The purpose of this study was to examine the changes in body composition, hormonal status, and physical fitness in 10.8 ± 0.3-year-old (n = 13), 12.7 ± 0.2-year-old (n = 14), and 14.7 ± 0.3-year-old (n = 12) Finnish regional youth soccer players during a 2-year monitoring period and to compare physical fitness characteristics of soccer players with those of age-matched controls (10.7 ± 0.3 years, n = 13; 14.7 ± 0.3 years, n = 10) not participating in soccer. Body composition was measured in terms of height, weight, muscle mass, percentage of body fat, and lean body weight of trunk, legs, and arms. Hormonal status was monitored by concentrations of serum testosterone and cortisol. Physical fitness was measured in terms of sprinting speed, agility, isometric maximal strength (leg extensors, abdominal, back, grip), explosive strength, and endurance. Age-related development was detected in all other measured variables except in the percentage of body fat. The results showed that the physical fitness of regional soccer players was better than that of the control groups in all age groups, especially in cardiovascular endurance (p < 0.01-0.001) and in agility (p < 0.01-0.001). In conclusion, playing in a regional level soccer team seems to provide training adaptation, which is beyond normal development and which in all likelihood leads to positive health effects over a prolonged period of time.

Development of body composition, hormone profile, physical fitness, general perceptual motor skills, soccer skills and on-the-ball performance in soccer-specific laboratory test among adolescent soccer players.

The aim of the present study was to examine the development of on-the-ball skills in soccer-specific laboratory test and to examine how traditional measures of body composition, hormone profile, physical fitness, general perceptual motor skills and soccer skills were related to performance measured in open skill environment among 10, 12, and 14-year-old regional male soccer players (n = 12/group). The measured variables were height, weight, fat, muscle mass, testosterone, 10m sprint, agility, counter movement jump, peripheral awareness, Eye- Hand-Foot coordination, passing skill, dribbling skill and on-the-ball skills (performance time and passing accuracy) in soccer-specific laboratory test. A significant main effect by age was found in all measured variables except in fat, in peripheral awareness and in passing accuracy. In discriminant analysis 63.9% (λ = 0.603, F = 4.600, p < 0.01) of the players were classified correctly based on physical fitness and general perceptual motor skills into three ability groups originally classified with performance time in soccer-specific laboratory test. Correlation co- efficient analysis with-in age groups revealed that variables associated with performance time in soccer-specific laboratory test were peripheral awareness (r = 0.72, p < 0.01) in 10-year-olds; testosterone (r = -0.70, p < 0.05), dribbling skill (r = 0.73, p < 0.01) and passing skill (r = 0.73, p < 0.01) in 12-year-olds; agility (r = 0.79, p < 0.01), counter movement jump (r = - 0.62, p < 0.01), dribbling skill (r = 0.80, p < 0.01) and passing skill (r = 0.58, p < 0. 05) in 14-year olds. Corresponding relationships with passing accuracy were weight (r = 0.59, p < 0.05), fat (r = 0.66, p < 0.05), 10m sprint (r = 0.71, p < 0.01) and countermovement jump (r = -0.64, p < 0.05) in 10-year-olds; Eye-Hand-Foot coordination (r = 0.63, p < 0.05) in 14-year- olds. The relationship between soccer-specific anticipation time and performance time in soccer- specific laboratory test was significant only in the 14-year-old age group (r = 0.76, p < 0.01). To conclude, on-the-ball skill performance in soccer-specific laboratory test improved with age and it seemed that soccer-specific perceptual skills became more and general perceptual motor skills less important with age in soccer-specific laboratory test. Key pointsPhysical fitness characteristics and general perceptual motor skills predicted performance time of the open skill soccer-specific laboratory test in the group of 10-14 year-old regional soccer players.Before puberty the players were able to compensate weaker soccer-specific skills with better general physical performance abilities.Soccer-specific skills became more important with age and at the age of 14 the players were not able to compensate soccer-specific skills with general physical performance abilities.Beside basic ball-handling skills it also important to recognize the importance of soccer-specific perceptual skills (anticipation and reaction) as a part of successful soccer performance.