Purpose. The aim of this study was to investigate the contextual interference effect on learning a sport-related task in older adults. Methods. We selected 40 physically active individuals aged 65-80 years that were randomly divided into random and blocked practice groups. The task comprised throwing a bocce ball to three targets at distances of 2, 4 and 6 m. Practice consisted of 120 trials divided into two sessions. Two retention tests at a distance of 4 m were conducted (post-10 min and 24 h) and then two transfer tests with a target at 5 m (post-24 h) were performed with the preferred and non-preferred hand. Task performance and movement patterns were measured. Results. Comparisons between the practice groups revealed no contextual interference effect (p > 0.05); the random group showed improved performance during practice (p < 0.05) but the blocked group did not. Overall, the results showed similar performance between the groups in the retention and transfer tests, although it was inferred that the blocked group made insufficient corrective adjustments. Conclusions. It was concluded that contextual interference did not affect the learning of a sport-based skill in older adults. Nonetheless, it can be argued that the parameter modifications may have negatively influenced learning this task by the practice groups and/or they may have required more practice time.
Keywords: Contextual interference; practice schedule; bocce; motor learning; older adults
Purpose. The aim of the study was to check whether and to what extent leisure-time physical activity and commuting activity constitute a factor differentiating physical fitness in a selected group of females and males aged 20-59 years. Methods. The study was performed in the Świętokrzyskie region of Poland in the spring of 2010. The sample included 1032 adults (517 females and 515 males) employed and at the same time completing extramural education or attending vocational improvement programs. Four age groups were delineated (20-29, 30-39, 40-49 and 50-59). A self-report questionnaire assessed physical activity level whereas physical fitness was determined by tests assessing handgrip strength, upper (dynamic) and lower (explosive) extremity strength, agility, hand movement speed, and endurance. Results. A significant relationship was found between leisure-time physical activity and all the performance-based measures in both females and males. With regard to commuting activity, statistically significant relationships were observed only in the females with regard to handgrip strength, lower extremity strength and endurance. Conclusions. A significant positive relationship between leisure-time physical activity and physical fitness was demonstrated in both females and males aged 20-59 years while commuting activity should significant correlations only in females.
Keywords: health; leisure-time; motor abilities; commuting activity
Purpose. While take-off accuracy and approach run velocity are known determinants of long and triple jump performance, the interaction of these factors with step length adjustment (SLA) is not as clear. Methods. The study involved 39 male and 31 female national-level long and triple jumpers. The Optojump Next device was used to analyse jump attempts. Three groups were identified according to maximum variability of footfall placement (HVF - high, MVF - medium, LVF - Low) as well as three groups regarding the onset of step length adjustment (ESLA - early, MSLA - mid, LSLA - late). Results. Take-off accuracy in the LVF and MVF groups was greater compared with the HVF group among females. Among males, the LVF group made significantly (p < 0.05) fewer foul attempts than the HVF group. The ESLA group achieved significantly (p < 0.05) higher velocity during the last five steps of the approach run than the LSLA group in men. Conclusions. Coaches should implement exercises targeting SLA in long and triple jump training exercises to improve performance.
Keywords: movement pattern; gait; speed; athletics
Purpose. The aim of the paper was to determine the occurrence of feet and ankle deformities in trampoline and artistic gymnasts. Methods. Ten acrobatic gymnasts (trampolinists) and 10 artistic gymnasts aged 6-14 years were recruited. The calcaneal-tibial (rearfoot) angle was determined as the angle of the upper calcaneal tendon and the longitudinal heel axis while Clarke angles were determined by podoscopy. Results. The trampolinists showed significantly greater medial angulation (calcaneal valgus) than the group of gymnasts. Right and left foot Clark’s angles in both the trampoline and artistic gymnasts were above 55°. Conclusions. Trampolinists exhibit significantly more pronounced calcaneal valgus than artistic gymnasts. The prevalence of foot and ankle deformities in both populations should be addressed by coaches in the gymnastics training of young children.
Key words: foot and ankle deformities; young gymnasts; acrobats-trampolinists
Purpose. Female runners are known to be at greater risk from chronic running injuries than age-matched males, although the exact mechanisms are often poorly understood. The aim of the current investigation was to determine if female recreational runners exhibit distinct limb and joint stiffness characteristics in relation to their male counterparts. Methods. Fourteen male and fourteen female runners ran over a force platform at 4.0 m · s-1. Lower limb kinematics were collected using an eight-camera optoelectric motion capture system operating at 250 Hz. Measures of limb and joint stiffness were calculated as a function of limb length and joint moments divided by the extent of limb and joint excursion. All stiffness and joint moment parameters were normalized to body mass. Sex differences in normalized limb and knee and ankle joint stiffness were examined statistically using independent samples t tests. Results. The results indicate that normalized limb (male = 0.18 ± 0.07, female = 0.37 ± 0.10 kN · kg · m-1) and knee stiffness (male = 5.59 ± 2.02, female = 7.34 ± 1.78 Nm · kg · rad-1) were significantly greater in female runners. Conclusions. On the basis that normalized knee and limb stiffness were shown to be significantly greater in female runners, the findings from the current investigation may provide further insight into the aetiology of the distinct injury patterns observed between sexes.
Key words: running; sex; limb stiffness; biomechanics
Purpose. Increased contact pressure and skin friction may lead to higher skin temperature. Here, we hypothesized a relationship between plantar pressure and foot temperature. To elicit different conditions of stress to the foot, participants performed running trials of barefoot and shod running. Methods. Eighteen male recreational runners ran shod and barefoot at a self-selected speed for 15 min over different days. Before and immediately after running, plantar pressure during standing (via a pressure mapping system) and skin temperature (using thermography) were recorded. Results. No significant changes were found in plantar pressure after barefoot or shod conditions (p > 0.9). Shod running elicited higher temperatures in the forefoot (by 0.5-2.2°C or 0.1-1.2% compared with the whole foot, p < 0.01) and midfoot (by 0.9-2.4°C, p < 0.01). Barefoot running resulted in higher temperature variation in the rearfoot (0.1-10.4%, p = 0.04). Correlations between skin temperature and plantar pressure were not significant (r < 0.5 and r > -0.5, p > 0.05). Conclusions. The increase in temperature after the shod condition was most likely the result of footwear insulation. However, variation of the temperature in the rearfoot was higher after barefoot running, possible due to a higher contact load. Changes in temperature could not predict changes in plantar pressure and vice-versa.
Keywords: sports; thermography; shoes; gait
Purpose. The aim of this study was to determine the magnitude of changes in anaerobic endurance in response to a training protocol targeting glycolytic capacity. Methods. The study involved 24 soccer players from two U-18 teams. One team served as an experimental (E) group the other a control (C). Besides standard soccer practice performed by both groups, an interval training protocol was administered to the experimental group twice a week (15 sessions). One training repetition involved running a soccerspecific course. Repetition time was equal to 15 s interspersed with 45 s passive recovery. Total number of repetitions was determined by the ability to maintain target time (power) in subsequent repetitions. A 5% reduction in the distance covered (m) compared with the first repetition ended a set. The number of sets was based on the ability of player to maintain target time per repetition. Rest interval between sets was 15 min. Anaerobic performance was assessed before and after the 8-week protocol by the Wingate test in which arterial blood gases, blood lactate concentration, and respiratory variables on a breath-by-breath basis were measured. Results. Distance covered in group E in the first training session was 470.38 ± 77.82 m and 1182.31 ± 164.44 m in the last session. Post-intervention total work (273.63 ± 18.32 to 284.98 ± 15.76 J/kg) and maximum power (13.28 ± 1.43 to 14.14 ± 1.25 W/kg) significantly increased in the Wingate test. Statistically significant increases in lactate concentration (10.64 ± 1.54 and 12.72 ± 1.59 mmol/l) and lower blood pH (7.21 ± 0.03 and 7.19 ± 0.02) were also observed. No significant changes in any of the above variables were observed in group C. Conclusions. Interval training develops glycolytic capacity but with large inter-individual variability.
Keywords: interval training; anaerobic endurance; glycolytic capacity; soccer
Purpose. The aim of the study was to investigate the social competence (SC) and emotional intelligence (EI) of future physical education (PE) teachers after targeted psychological training. Methods. PE university students completing their bachelor’s (28 third-year students) and master’s degrees (31 first-year students) were recruited and divided into an experimental and control group. The participants completed a questionnaire assessing SC and EI. The experimental group then participated in a series of psychological workshops (four 8-hour sessions) that included Video Interaction Training and interpersonal training. The questionnaire was again administered immediately and 6 months after the workshops were completed. Results. The indicators of SC and EI were significantly higher in experimental group in both post-workshop time points. No increases were observed in the control group. Conclusions. The results justify the inclusion of interactive psychological courses in the curricula of future PE teachers.
Keywords: social competence; emotional intelligence; psychological workshops; physical education teachers
University School of Physical Education in Wrocław
al. I. J. Paderewskiego 35
51-612 Wrocław, Poland