The purpose of this study was to compare the injured versus noninjured lower extremity on three single-leg hop tests following inversion ankle sprain. Twenty-two subjects with a history of unilateral inversion ankle sprain participated in this study. Subjects performed the three single-leg hop tests (hop for distance, hop for time, and agility hop). An independent t test was used to compare extremities. No significant differences existed on any hop test for the 22 subjects. In 8 of the 22 subjects who reported pain with activities of daily living and/or sports activities, an independent t test revealed no significant difference on hop test performance between extremities. We conclude that these three single-leg hop tests lack sensitivity (validity) in detecting lower extremity performance deficits as reported by the subjects following inversion ankle sprain.
Teddy W. Worrell, Laurie D. Booher and Karla M. Hench
Jeffrey Paszkewicz, Tristen Webb, Brian Waters, Cailee Welch McCarty and Bonnie Van Lunen
There is a high incidence of anterior cruciate ligament (ACL) injury in adolescents participating in pivoting sports such as soccer, basketball, and handball. Most ACL injuries in athletes are noncontact injuries, with a mechanism of sudden deceleration, change in direction, or landing from a jump. These mechanisms coupled with an increase in contraction of the quadriceps have been shown as risk factors for ACL injuries. Injuries to the ACL may require surgery, a long rehabilitation, and the potential for reinjury. Studies have shown reductions in lower extremity injury rates using training protocols that focus on landing mechanics, balance training, strength training, and/or agility training. There has been some thought that starting preventive training programs with adolescent athletes may be the most effective approach to reducing adolescent ACL injuries.
Focused Clinical Question:
Can lower extremity injury-prevention programs effectively reduce ACL injury rates in adolescent athletes?
Justin W.L. Keogh, Andrew Kilding, Philippa Pidgeon, Linda Ashley and Dawn Gillis
Dancing is a mode of physical activity that may allow older adults to improve their physical function, health, and well-being. However, no reviews on the physical benefits of dancing for healthy older adults have been published in the scientific literature. Using relevant databases and keywords, 15 training and 3 cross-sectional studies that met the inclusion criteria were reviewed. Grade B–level evidence indicated that older adults can significantly improve their aerobic power, lower body muscle endurance, strength and flexibility, balance, agility, and gait through dancing. Grade C evidence suggested that dancing might improve older adults’ lower body bone-mineral content and muscle power, as well as reduce the prevalence of falls and cardiovascular health risks. Further research is, however, needed to determine the efficacy of different forms of dance, the relative effectiveness of these forms of dance compared with other exercise modes, and how best to engage older adults in dance participation.
James Zois, David Bishop and Rob Aughey
High-intensity, short-duration warm-up techniques improve acute physical performance, but sparse research has examined their consequence when followed by intermittent activity, which is pertinent to team sports. The authors compared a 5-repetition-maximum (5RM) leg-press, a small-sided game (SSG), and a current team-sport warm-up in 10 semiprofessional soccer players after 2 intermittent-activity protocols consisting of 15 repetitions of a 60-s circuit that included sprinting, slalom, walking, jogging, decelerations, changes of direction, backward running, and striding activities. There was a large improvement in countermovement-jump height in the 5RM after the 1st intermittent-activity protocol (mean, ±90% CL 6.0, ±4.0%, P = .03) and a small improvement after the 2nd (4.6, ±4.0%, P = .04) compared with team sport. Reactive agility was moderately faster via 5RM after the 1st intermittent-activity protocol (3.1, ±2.6%: P = .04) and the 2nd (5.7, ±2.7%, P = .001) than via SSG. There was a small improvement in reactive agility after the 1st intermittent-activity protocol in the 5RM, compared with team sport (3.3, ±2.9%, P = .04). There was a small improvement in mean 20-m-sprint times after both intermittent-activity protocols in the 5RM, compared with SSG (4.2, ±2.0%, P = .01, and 4.3, ±2.0%, P = .01) and, after the 1st intermittent-activity protocol only, compared with team sport (4.2, ±2.1%, P = 0.02). Small increases in blood lactate concentration were observed (46.7, ±18.6%, P = .01) in the 5RM compared with the SSG after the 2nd intermittent-activity protocol. Improved performances after the 5RM warm-up should encourage practitioners to reduce activity time and include high-intensity tasks in team-sport warmups aimed at inducing a potentiating effect.
Jan Boone and Jan Bourgois
The current study aimed to gain insight into the physiological profile of elite basketball players in Belgium in relation to their position on the field.
The group consisted of 144 players, divided into 5 groups according to position (point guards [PGs], shooting guards [SGs], small forwards [SFs], power forwards [PFs], and centers [Cs]). The anthropometrics were measured and the subjects underwent fitness tests (incremental running test, 10-m sprint, 5 ×-10 m, squat and countermovement jump, isokinetic test) to obtain insight into endurance, speed, agility, and power. The parameters of these tests were compared among the different positions by means of 1-way variance analysis (MANOVA). Tukey post hoc tests were performed in case of a significant MANOVA.
It was observed that Cs were taller and heavier and had a higher percentage body fat than PGs and SGs. For the anaerobic sprint test Cs were slower than the other positions. For the 5 × 10-m the PGs and SGs were faster than SFs and PFs. For the jump test Cs displayed a significantly lower absolute performance than the other positions. PGs and SGs had a higher VO2peak and speed at the anaerobic threshold than PFs and Cs. The isokinetic strength test showed that the quadriceps muscle group of Cs could exert a higher torque during knee extension than the other positions.
The current study showed that the physiological profile of elite players in the Belgian first division differs by player position. More specifically, guards were characterized by high endurance, speed, and agility, whereas centers and power forwards had higher muscle strength than the other positions.
Juan Del Coso, Alberto Pérez-López, Javier Abian-Vicen, Juan Jose Salinero, Beatriz Lara and David Valadés
There are no scientific data about the effects of caffeine intake on volleyball performance. The aim of this study was to investigate the effect of a caffeine-containing energy drink to enhance physical performance in male volleyball players. A double-blind, placebo-controlled, randomized experimental design was used. In 2 different sessions separated by 1 wk, 15 college volleyball players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed volleyball-specific tests: standing spike test, maximal squat jump (SJ), maximal countermovement jump (CMJ), 15-s rebound jump test (15RJ), and agility T-test. Later, a simulated volleyball match was played and recorded. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the spike test (73 ± 9 vs 75 ± 10 km/h, P < .05) and the mean jump height in SJ (31.1 ± 4.3 vs 32.7 ± 4.2 cm, P < .05), CMJ (35.9 ± 4.6 vs 37.7 ± 4.4 cm, P < .05), and 15RJ (29.0 ± 4.0 vs 30.5 ± 4.6 cm, P < .05). The time to complete the agility test was significantly reduced with the caffeinated energy drink (10.8 ± 0.7 vs 10.3 ± 0.4 s, P < .05). In addition, players performed successful volleyball actions more frequently (24.6% ± 14.3% vs 34.3% ± 16.5%, P < .05) with the ingestion of the caffeinated energy drink than with the placebo drink during the simulated game. A caffeine-containing energy drink, with a dose equivalent to 3 mg of caffeine per kg body mass, might be an effective ergogenic aid to improve physical performance and accuracy in male volleyball players.
Jaime Fernandez-Fernandez, David Sanz, Jose Manuel Sarabia and Manuel Moya
To compare the effects of combining high-intensity training (HIT) and sport-specific drill training (MT) versus sportspecific drill training alone (DT) on fitness performance characteristics in young tennis players.
Twenty young tennis players (14.8 ± 0.1 y) were assigned to either DT (n = 10) or MT (n = 10) for 8 wk. Tennis drills consisted of two 16- to 22-min on-court exercise sessions separated by 3 min of passive rest, while MT consisted of 1 sport-specific DT session and 1 HIT session, using 16–22 min of runs at intensities (90–95%) related to the velocity obtained in the 30–15 Intermittent Fitness Test (VIFT) separated by 3 min of passive rest. Pre- and posttests included peak oxygen uptake (VO2peak), VIFT, speed (20 m, with 5- and 10-m splits), 505 Agility Test, and countermovement jump (CMJ).
There were significant improvements after the training period in VO2peak (DT 2.4%, ES = moderate; MT 4.2%, ES = large) and VIFT (DT 2.2%, ES = small; MT 6.3%, ES = large) for both DT and MT, with no differences between training protocols. Results also showed a large increase in the 505 Agility Test after MT, while no changes were reported in the other tests (sprint and CMJ), either for MT or DT.
Even though both training programs resulted in significant improvements in aerobic performance, a mixed program combining tennis drills and runs based on the VIFT led to greater gains and should be considered the preferred training method for improving aerobic power in young athletes.
Patrick Delisle-Houde, Nathan A. Chiarlitti, Ryan E.R. Reid and Ross E. Andersen
Ice hockey is a physically demanding contact sport that requires players to perform repeated bouts of high-energy output shifts lasting 30 to 80 seconds. 1 , 2 Ice hockey players are required to develop many physical attributes such as speed, agility, and flexibility to perform optimally in the
Peggy M. Roswal, Claudine Sherrill and Glenn M. Roswal
This study compared the effectiveness of data based and creative dance pedagogies in relation to motor skill performance and self-concept of mentally retarded students. Subjects (N=35) were moderately mentally retarded males and females, ages 11 to 16 years, in special education classes. Their mean age was 12.88 years in the data based group and 13.47 years in the creative dance group. Excluding testing, the study lasted 8 weeks. Each group received 40 lessons of 30 minutes each. Data based pedagogy was based on the work of Dunn, Morehouse, and Dalke (1979), and creative dance pedagogy was based primarily on the work of Riordan (Fitt & Riordan, 1980). Pretest and posttest data were collected through administration of the Data Based Dance Skills Placement Test, selected subtests of the Cratty Six-Category Gross Motor Test, and the Martinek-Zaichkowsky Self-Concept Scale. Multivariate analysis of covariance revealed no difference between pedagogies. The group means indicated improvement in dance skill performance but not in self-concept or body perception, balance, and gross and locomotor agility.
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.