considerable decrease in the risk of fall-related injuries. In the motor learning field, numerous factors can influence the efficacy of skill practice. One of the learning phenomena that occurs during multiple skills practice is the contextual interference effect (CI). The interference is created when motor
Saša Krstulović, Andrea De Giorgio, Óscar DelCastillo Andrés, Emerson Franchini, and Goran Kuvačić
Takehide Kimura and Ryouta Matsuura
When an individual performs two tasks simultaneously, performance in either one or both tasks often decreases. This decrement in performance is defined as dual-task interference ( Ebersbach, Dimitrijevic, & Poewe, 1995 ). In our daily life, we perform various combinations of dual tasks and
Nicholas Stanger, Ryan Chettle, Jessica Whittle, and Jamie Poolton
). However, research has neglected to examine how emotions experienced before and during performance are linked with specific internal thought disruptions (i.e., cognitive interference) or to test for amenable moderators of such relationships. Such research would guide sport practitioners (e.g., coaches
Markus Janczyk and Wilfried Kunde
According to the Perception-Action-Model (PAM), the human visual cortex consists of the ventral vision-for-perception and the dorsal vision-for-action streams. Performance decrements with increasing variation of nominally task-irrelevant stimulus features (Garner-Interference) was suggested as an empirical tool for identifying contributions of these streams: vision-for-perception, but not visionfor-action, should suffer from Garner-Interference, but inconsistencies in this argument were revealed by several studies. We here used a new manipulation to induce Garner-Interference in a dorsal task: The stimulus objects did not differ in their lengths but in the side to which they were weighted. In Experiment 1, Garner-Interference was found in a ventral perceptual judgment task. Notably, we did also find Garner-Interference in skilled right-handed grasping in Experiment 2. These findings suggest that the presence or absence of Garner-Interference does not consistently index the contribution of different processing streams for perception and action, but the coprocessing of nominally task-irrelevant stimulus features in general, be it for perception of action.
Julien Robineau, Mathieu Lacome, Julien Piscione, Xavier Bigard, and Nicolas Babault
To assess the impact of 2 high-intensity interval-training (HIT) programs (short interval vs sprint interval training) on muscle strength and aerobic performances in a concurrent training program in amateur rugby sevens players.
Thirty-six amateur rugby sevens players were randomly assigned to strength and short interval training (INT), strength and sprint interval training (SIT), or a strength-only training group (CON) during an 8-wk period. Maximal strength and power tests, aerobic measurements (peak oxygen uptake [VO2peak] and maximal aerobic velocity), and a specific repeated-sprint ability (RSA) test were conducted before and immediately after the overall training period.
From magnitude-based inference and effect size (ES ± 90% confidence limit) analyses, the current study revealed substantial gains in maximal strength and jump-height performance in all groups. The difference in change of slow concentric torque production was greater in CON than in SIT (0.65 ± 0.72, moderate). VO2peak and, consequently, mean performance in the RSA test were improved in the SIT group only (0.64 ± 0.29, moderate; –0.54 ± 0.35, moderate).
The study did not emphasize interference on strength development after INT but showed a slight impairment of slow concentric torque production gains after SIT. Compared with INT, SIT would appear to be more effective to develop VO2peak and RSA but could induce lower muscle-strength gains, especially at low velocity.
Dana Maslovat, Romeo Chua, Timothy D. Lee, and Ian M. Franks
This experiment examined contextual interference in producing a bimanual coordination pattern of 90° relative phase. Acquisition, retention, and transfer performance were compared in a single-task control group and groups that performed 2 tasks in either a blocked or random presentation. Surprisingly, acquisition data revealed that both the random and control groups outperformed the blocked group. Retention data showed a typical CI effect for performance variability, with the random group outperforming the blocked group. Neither the random nor blocked groups outperformed the control group, suggesting interference of a second task may be as beneficial to learning as extra practice on the initial task. No group effects were found during transfer performance. Results suggest that random practice is beneficial for learning only one task.
Xiaogang Hu and Karl M. Newell
This study investigated the asymmetry of bilateral interference in relation to the relative difference of force amplitude between hands and the hand dominance. In Experiment 1, one hand produced a fixed constant force of 5% maximum voluntary contraction (MVC) while the other hand produced different constant forces of 5%, 20%, and 50% MVC in blocked conditions. Asymmetric interference in force amplitude alone was evident in that the hand producing the fixed low force showed a stronger interference than the hand performing the higher force. Asymmetric interference in hand dominance was also found in that more interference was observed when the nondominant left hand produced the higher force, a finding that does not support the hemisphere specialization hypothesis. Experiment 2 was performed to rule out the fixed force level interpretation compared with the low force level account and the fixed force was set at 50% MVC. The results were consistent with the findings in Experiment 1 showing asymmetric interference with force amplitude rather than with fixed force level. The findings revealed that without a timing constraint the task demand associated with force amplitude alone can induce the asymmetric bilateral interference. The external task asymmetry and intrinsic asymmetry of the organism interact and influence the bimanual force coordination and control patterns.
Erik Lundkvist, Henrik Gustafsson, Paul Davis, and Peter Hassmén
The aims of this study were to (a) examine the associations between workaholism and work-related exhaustion and (b) examine associations between work–home/ home–work interference and work-related exhaustion in 261 Swedish coaches. Quantile regression showed that workaholism is only associated with exhaustion for coaches who score high on exhaustion, that negative work–home interference has a stronger association with exhaustion than negative home–work interference, and that the coaches on a mean level scored low on all measured constructs. In addition, coaches in the higher percentiles have a higher risk for burnout. Our results highlight the importance of studying coach exhaustion with respect to aspects that extend beyond the sports life.
Veerle Puttemans, Sophie Vangheluwe, Nicole Wenderoth, and Stephan P. Swinnen
When performing movements with different spatial trajectories in both upper limbs simultaneously, patterns of interference emerge that can be overcome with practice. Even though studies on the role of augmented feedback in motor learning have been abundant, it still remains to be discovered how overcoming such specific patterns of spatial interference can be optimized by instructional intervention. In the present study, one group acquired a bimanual movement with normal vision, whereas a second group received augmented feedback of the obtained trajectories on a computer screen in real time. Findings revealed that, relative to normal vision, the augmented feedback hampered skill learning and transfer to different environmental conditions. These observations are discussed in view of the benefits and pitfalls of augmented feedback in relation to task context and instructional condition.
Jacqueline M. Edwards, Digby Elliott, and Timothy D. Lee
An experiment is reported that investigated the effects of contextual interference on motor skill acquisition, and transfer of training in Down’s syndrome adolescents. Twenty Down’s syndrome adolescents and 20 nonhandicapped mental age controls learned a coincident anticipation timing task using either a random or a blocked training schedule. For transfer to a novel but similar task, subjects from both populations evidenced beneficial effects due to random practice. These data are discussed in terms of recent developments for strategy enhancement in motor learning by mentally retarded individuals.