Traditionally, lower extremity strength assessment has been performed in an open kinetic chain. Several authors, however, recommend closed kinetic chain assessment of lower extremity performance. Reliability of closed kinetic chain tests is not available. Therefore, the purpose of this study was to determine the reliability of the following single-leg hop tests: hop for distance, 6-m hop for time, and 30-m agility hop. Eighteen subjects (4 males and 14 females) participated in this study. An ANOVA repeated measures analysis revealed significant differences between the test trials within and between sessions for all dependent variables. However, when the mean of two test trials was analyzed, the three single-leg hop tests values were stable, that is, intraclass correlation coefficient (ICC 2,1) ranged from 0.77 to 0.99. Results demonstrate that these three single-leg hop tests were reliable as used in this study. Future research is needed to determine the sensitivity of these tests in the assessment of lower extremity performance following injury and following rehabilitation procedures.
Laurie D. Booher, Karla M. Hench, Teddy W. Worrell and Jill Stikeleather
Pauline Maillot, Alexandra Perrot, Alan Hartley and Manh-Cuong Do
The purposes of this present research were, in the first study, to determine whether age impacts a measure of postural control (the braking force in walking) and, in a second study, to determine whether exergame training in physically-simulated sport activity would show transfer, increasing the braking force in walking and also improving balance assessed by clinical measures, functional fitness, and health-related quality of life in older adults. For the second study, the authors developed an active video game training program (using the Wii system) with a pretest-training-posttest design comparing an experimental group (24 1-hr sessions of training) with a control group. Participants completed a battery comprising balance (braking force in short and normal step conditions), functional fitness (Senior Fitness Test), and health-related quality of life (SF-36). Results show that 12 weeks of video game-based exercise program training improved the braking force in the normal step condition, along with the functional fitness of lower limb strength, cardiovascular endurance, and motor agility, as measured by the Senior Fitness Test. Only the global mental dimension of the SF-36 was sensitive to exergame practice. Exergames appear to be an effective way to train postural control in older adults. Because of the multimodal nature of the activity, exergames provide an effective tool for remediation of age-related problems.
Jaime Fernandez-Fernandez, Eduardo Sáez De Villarreal, David Sanz-Rivas and Manuel Moya
The aim of this study was to analyze the effects of an 8-week (conducted biweekly for a total of 16 sessions) plyometric training program (PT) (e.g., upper- and lower-body exercises) combined with regular tennis training on physical qualities in young tennis players.
Sixty tennis players between the ages of 12 and 13 years (age 12.5 ± 0.3 years, weight 44.2 ± 7.0 kg, height 156.6 ± 7.1 cm) were allocated to either the control group (standard in-season regimen) (CG; n = 30) or the experimental group, which received an additional PT (TG; n = 30) for 30–60 min as a substitute for some tennis training within the usual 90-min practice.
Pre- and posttests included: anthropometric measures; vertical countermovement jump (CMJ); standing long jump (SLJ); 20 m sprint time (with 5 and 10 m splits); a modified 505 agility test; overhead medicine ball throw; and serve velocity test.
After the training intervention, the TG showed significant (p < .01) improvements in all the parameters analyzed, with percentages of change and effect sizes ranging from 3.1% to 10.1% and 0.4 (small) to 1.3 (moderate), respectively. No significant changes were observed in the CG after the training intervention.
PT was shown as an important stimulus for enhancing explosive actions in young tennis players.
Kathryn Froiland, Wanda Koszewski, Joshua Hingst and Lisa Kopecky
A survey was conducted to examine the source of information and usage of nutritional supplements in 115 male and 88 female varsity athletes at a Division I university. The survey asked each athlete to define supplement, and report supplement use and type, source of information, and reasons for use. Supplement use frequencies were determined, and comparisons were made between gender and sport. Eighty-nine percent of the subjects had or were currently using nutritional supplements. Many athletes did not consider sports drinks and calorie replacement products as supplements. Females were more likely to take calcium and multivitamins, and males had significant intake for ginseng, amino acids, glutamine, hydroxy-methyl-buterate (HMB), weight gainers, whey protein, and Juven. The most frequently used supplements overall were energy drinks (73%), calorie replacement products of all types (61.4%), multivitamin (47.3%), creatine (37.2%), and vitamin C (32.4%). There was also significant supplement use noted per sport. Females were more likely to obtain information from family members regarding supplementation, and males from a store nutritionist, fellow athletes, friends, or a coach. Female athletes were more likely to take supplements for their health or because of an inadequate diet, while men reported taking supplements to improve speed and agility, strength and power, or for weight/muscle gain.
Gregory R. Cox, Iñigo Mujika and Cees-Rein van den Hoogenband
Water polo is an aquatic team sport that requires endurance, strength, power, swimming speed, agility, tactical awareness, and specific technical skills, including ball control. Unlike other team sports, few researchers have examined the nutritional habits of water polo athletes or potential dietary strategies that improve performance in water polo match play. Water polo players are typically well muscled, taller athletes; female players display higher levels of adiposity compared with their male counterparts. Positional differences exist: Center players are heavier and have higher body fat levels compared with perimeter players. Knowledge of the physical differences that exist among water polo players offers the advantage of player identification as well as individualizing nutrition strategies to optimize desired physique goals. Individual dietary counseling is warranted to ensure dietary adequacy, and in cases of physique manipulation. Performance in games and during quality workouts is likely to improve by adopting strategies that promote high carbohydrate availability, although research specific to water polo is lacking. A planned approach incorporating strategies to facilitate muscle glycogen refueling and muscle protein synthesis should be implemented following intensified training sessions and matches, particularly when short recovery times are scheduled. Although sweat losses of water polo players are less than what is reported for land-based athletes, specific knowledge allows for appropriate planning of carbohydrate intake strategies for match play and training. Postgame strategies to manage alcohol intake should be developed with input from the senior player group to minimize the negative consequences on recovery and player welfare.
Ricardo Rebelo-Gonçalves, Manuel João Coelho-e-Silva, Vítor Severino, Antonio Tessitore and António José Barata Figueiredo
Studies focused on position-related characteristics of young soccer players often ignore the goalkeepers. The aim of this study was to examine the effect of playing position on anthropometry, physiological attributes, soccer skills, and goal orientation across adolescence. One hundred forty-five soccer players age 11–19 y were assessed in training experience, body size, maturation, physiological parameters, soccer skills, and goal orientation. Factorial ANOVA was used to test the effect of age group, playing position, and respective interaction terms, while analysis of variance was used to compare goalkeepers vs outfielders in middle (under 13 [U-13] and U-15) and late (U-17 and U-19) adolescence. Discriminant analysis was used to identify the variables that contributed to explaining playing positions. Age group was a consistent source of variation for all variables except task and ego orientations. Fat mass, agility, endurance, dribbling speed, shooting accuracy, and passing were affected by the gradient derived from the classification between goalkeepers and outfielders. It was possible to correctly classify the playing position based on fat-free mass and 3 manipulative skills in younger players and on 4 skills in U-17 and U-19 soccer players. Future research should include longitudinal information to improve our understanding of the factors that contribute to distinguish goalkeepers from outfielders.
Anneke G. van der Niet, Joanne Smith, Jaap Oosterlaan, Erik J.A. Scherder, Esther Hartman and Chris Visscher
The objective of this study was to analyze the effects of a physical activity program including both aerobic exercise and cognitively engaging physical activities on children’s physical fitness and executive functions. Children from 3 primary schools (aged 8–12 years) were recruited. A quasi-experimental design was used. Children in the intervention group (n = 53; 19 boys, 34 girls) participated in a 22-week physical activity program for 30 min during lunch recess, twice a week. Children in the control group (n = 52; 32 boys, 20 girls) followed their normal lunch routine. Aerobic fitness, speed and agility, and muscle strength were assessed using the Eurofit test battery. Executive functions were assessed using tasks measuring inhibition (Stroop test), working memory (Visual Memory Span test, Digit Span test), cognitive flexibility (Trailmaking test), and planning (Tower of London). Children in the intervention group showed significantly greater improvement than children in the control group on the Stroop test and Digit Span test, reflecting enhanced inhibition and verbal working memory skills, respectively. No differences were found on any of the physical fitness variables. A physical activity program including aerobic exercise and cognitively engaging physical activities can enhance aspects of executive functioning in primary school children.
Gal Ziv and Ronnie Lidor
The soccer goalkeeper (GK) is required to perform strenuous actions during practice sessions and actual games. One of the objectives of those professionals who work with GKs is to obtain relevant information on physical characteristics and physiological attributes of GKs, and to use it effectively when planning training programs for them. This article has three purposes: (a) to review a series of studies (n = 23) on physical characteristics, physiological attributes, and on-field performances of soccer GKs; (b) to outline a number of methodological limitations and research concerns associated with these studies; and (c) to suggest several practical recommendations for soccer coaches who work with GKs. Four main fndings emerged from our review: (a) professional adult GKs usually are over 180 cm tall and have a body mass of over 77 kg; (b) studies on agility and speed produced mixed results, with some showing similar values between GKs and field players and others showing reduced performance in GKs; (c) GKs usually have higher vertical jump values when compared with players playing the various field positions; (d) GKs cover approximately 5.5 km during a game, mostly by walking and jogging. Four methodological limitations and research concerns associated with the reviewed studies were discussed, among them the lack of a longitudinal approach and the lack of on-field performance studies. Three practical recommendations are made for coaches, one of which is that coaches should adopt a careful approach when selecting testing protocols and devices for the assessment of GKs’ physiological attributes.
Jacqueline M. Miotto, Wojtek J. Chodzko-Zajko, Jennifer L. Reich and Melissa M. Supler
A limiting factor in evaluating the functional status of older people is the lack of appropriate measurement tools for assessing functional mobility, muscle strength, aerobic endurance, agility, and flexibility. In this study, the reliability and validity of the seven-item Fullerton Functional Fitness Test (FFT) battery, designed for use with community-dwelling older adults, was examined. The test items were as follows: floor sit-and-reach, back scratch, 8-ft up-and-go, arm curl, 30-s chair stand. 2-min step, and 9-min walk. Seventy-nine participants (42 physically active, 37 sedentary) completed the FFT battery three times within a 2-week period. The test-retest reliability intraclass correlation coefficients were high. Construct validity analysis revealed that five of the seven FFT items discriminated between the physically active and sedentary groups. In conclusion, most of the evidence from the stability reliability and discriminant validity analyses supports the view that the Fullerton FFT battery is a reliable and valid test of functional fitness.
Thomas A. Haugen, Espen Tønnessen, Jonny Hisdal and Stephen Seiler
The overall objective of this review was to investigate the role and development of sprinting speed in soccer. Time–motion analyses show that short sprints occur frequently during soccer games. Straight sprinting is the most frequent action before goals, both for the scoring and assisting player. Straight-line sprinting velocity (both acceleration and maximal sprinting speed), certain agility skills, and repeated-sprint ability are shown to distinguish groups from different performance levels. Professional players have become faster over time, indicating that sprinting skills are becoming more and more important in modern soccer. In research literature, the majority of soccer-related training interventions have provided positive effects on sprinting capabilities, leading to the assumption that all kinds of training can be performed with success. However, most successful intervention studies are time consuming and challenging to incorporate into the overall soccer training program. Even though the principle of specificity is clearly present, several questions remain regarding the optimal training methods within the larger context of the team-sport setting. Considering time-efficiency effects, soccer players may benefit more by performing sprint-training regimens similar to the progression model used in strength training and by world-leading athletics practitioners, compared with the majority of guidelines that traditionally have been presented in research literature.