The aim of this observational cross-sectional survey was to determine the prevalence of rapid weight loss (RWL) in elite kickboxers. Kickboxers (61 males; age = 24.2 ± 4.6 years, weight = 73.9 ± 12.8 kg, and height = 179.2 ± 7.9 cm) from eight European countries completed a Rapid Weight Loss Questionnaire regarding prevalence, magnitude, and methods of RWL. All athletes (100%) were practicing RWL before the competition with a Rapid Weight Loss Questionnaire score of 52.4 ±12.9. Most kickboxers ‘usually lose between 2% and 5% of their body mass, whereas ∼30% lose between 6% and 8%. However, it is alarming that almost 30% reported cutting 10% of body weight or more sometime during their kickboxing career. Almost half of the athletes always practice gradual dieting (45.9%) and increased exercising (44.3%) to reduce body mass. Kickboxers usually reduce weight three to four times during a year, usually 7–15 days before a competition. More than a third (34.4%) started with RWL practice under the age of 17. There was no significant difference between weight divisions in weight management behaviors (p = .5, F = 0.6; η2 = .0) and no relation between the main characteristics of elite kickboxing athletes and the total RWL score. In conclusion, RWL practices in kickboxing athletes are somewhat specific and different when compared with other combat sports, which can be explained by greater number of weight classes and specific weigh-in protocol.
Boris Dugonjić, Saša Krstulović, and Goran Kuvačić
Damir Sekulic, Sasa Krstulovic, Ratko Katic, and Ljerka Ostojic
In this article we compared the effects of 9 months of judo training (JT; N = 41) and recreational sports games training (SGT; N = 57) on the fitness development of 7-year-old boys. Both programs were performed three times per week. Apart from body height, body weight, and skinfold thickness (SUM2SF), changes in muscular and cardiovascular endurance, flexibility, speed, agility, and coordination were studied. Using the analysis of variance, we found no differences between the groups at study entry, but after 9 months the JT participants achieved significantly better results in the shuttle-run task to test agility, the sit-up test for abdominal muscle endurance, and the sit-and-reach test for flexibility. The JT group also maintained their SUM2SF over the 9-month period, whereas the SGT group showed a significant increase in SUM2SF. No differences were observed between the groups in coordination, flexibility of the shoulder joint, speed, endurance, body height, and body weight. In conclusion, the specialized JT allowed the participants to improve more of their fitness capacities compared with nonspecialized SGT.
Saša Krstulović, Andrea De Giorgio, Óscar DelCastillo Andrés, Emerson Franchini, and Goran Kuvačić
The main aim of this investigation was to determine the effect of high contextual interference (HCI) and low contextual interference (LCI) on motor learning of falling techniques. Thirty-five kinesiology students (21 males and 14 females; mean ± SD, age = 19.4 ± 0.69 years) were randomly assigned to the HCI or LCI practice group. The participants’ task was to learn two judo falling techniques on both sides over 3 weeks. The two-way analysis of variance found no difference between LCI and HCI in the performance at the pretest, posttest, retention, and transfer. Both groups improved posttest and retention performance. Finally, differences were found for both groups between the falling performance in the posttest and the application test (except for the right yoko ukemi fall in the HCI). Lower application test scores led to the conclusion that the 3-week treatment was insufficient to reach the application level of the falling techniques.