Is there a contextual interference effect for sub-elite alpine ski racers learning complex skills?

Scientific understanding of the contextual interference effect stems mainly from studies on unskilled participants learning artificial laboratory tasks. Although one goal of such studies is to extrapolate the findings to include real-world learning situations such as sports, this generalization is not straightforward. This study tested the contextual interference effect with 66 sub-elite, competitive alpine ski racers who learned a new movement pattern−the pumping technique to increase velocity in slalom−by practicing this skill in three different slalom courses over a 3-day training period. The interleaved group practiced all three courses each day in a semi-random order. In contrast, the blocked group practiced only one course each day, which was randomized and counterbalanced across the participants in this group. A retention test was delivered 72 h after the last practice day. In contrast to our hypothesis, the interleaved group did not display significantly better retention than the blocked group. The interleaved group’s performance was also not significantly attenuated during skill learning compared to the blocked group. Our results underscore the importance of conducting motor learning experiments in natural environments to understand the conditions that facilitate learning beyond the laboratory environment.

Always Pay Attention to Which Model of Motor Learning You Are Using

This critical review considers the epistemological and historical background of the theoretical construct of motor learning for a more differentiated understanding. More than simply reflecting critically on the models that are used to solve problems-whether they are applied in therapy, physical education, or training practice-this review seeks to respond constructively to the recent discussion caused by the replication crisis in life sciences. To this end, an in-depth review of contemporary motor learning approaches is provided, with a pragmatism-oriented clarification of the researcher's intentions on fundamentals (what?), subjects (for whom?), time intervals (when?), and purpose (for what?). The complexity in which the processes of movement acquisition, learning, and refinement take place removes their predictable and linear character and therefore, from an applied point of view, invites a great deal of caution when trying to make generalization claims. Particularly when we attempt to understand and study these phenomena in unpredictable and dynamic contexts, it is recommended that scientists and practitioners seek to better understand the central role that the individual and their situatedness plays in the system. In this way, we will be closer to making a meaningful and authentic contribution to the advancement of knowledge, and not merely for the sake of renaming inventions.

The Effect of Choice on Motor Learning for Learners With Different Levels of Intrinsic Motivation

This study examines whether the positive effect of choice on motor learning in a dart-throwing task varies by intrinsic motivation. Participants were allocated to a highly motivated or less-motivated group based on measured task motivation and randomly to a Choice or No Choice group. In Experiment 1, participants in the Choice group chose their dart color. In Experiment 2, they chose when to observe a model demonstration. Results showed that the effect of choice on motor learning differed between highly and less-motivated participants in Experiment 1 (i.e., interaction between motivation and choice) but not Experiment 2 (i.e., main effects of motivation and choice). Specifically, motor learning was enhanced in less-motivated but not highly motivated participants when choosing dart color, while it was enhanced regardless of initial intrinsic motivation when choosing model-demonstration time. Therefore, external provision of choice in a motor-learning situation may not be equally effective across learners.

The role of the practice order: A systematic review about contextual interference in children

Aim

We aimed to identify and evaluate the quality and evidence of the motor learning literature about intervention studies regarding the contextual interference (CI) effect (blocked vs. random practice order) in children with brain lesions and typically developing (TD) children.

Method

Eight databases (Cinahl, Cochrane, Embase, PubMed, Pedro, PsycINFO, Scopus and Web of Knowledge) were searched systematically with predefined search terms. Controlled studies examining the CI effect in children (with brain lesions or TD) were included. Evidence level, conduct quality, and risk of bias were evaluated by two authors independently. A best evidence synthesis was performed.

Results

Twenty-five papers evaluating TD children were included. One of these studies also assessed children with cerebral palsy. Evidence levels were I, II, or III. Conduct quality was low and the risk of bias high, due to methodological issues in the study designs or poor description thereof. Best evidence synthesis showed mainly no or conflicting evidence. Single tasks showed limited to moderate evidence supporting the CI effect in TD children.

Conclusion

There is a severe limitation of good-quality evidence about the CI effect in children who practice different tasks in one session, especially in children with brain lesions.

Effects of Contextual Interference on Retention of Three Volleyball Skills

Previous research in motor learning has shown that random practice schedules facilitate retention and transfer of motor skills more than repetitive practice schedules. The purpose of this study was to investigate the generalizability of contextual interference effects. High school students (63 boys, 76 girls) from three physical education class periods were randomly assigned to one of three practice conditions, random, random-blocked, or blocked practice within a class period. Three teachers were randomly assigned to a practice group within a class period and taught a different practice condition each class period. There were nine groups with three practice groups per class period. Subjects practiced the volleyball forearm pass, set, or overhead serve for 30 trials every day for nine class periods. All subjects recorded scores for their practice trials each day during acquisition and were posttested after a 2-day retention interval. Analysis of variance indicated significant improvement in all groups but no significant effects of practice condition during acquisition or retention. These findings suggest that practice was long enough to produce change during acquisition. However, factors characteristic of physical education classes may reduce or mask contextual interference effects commonly observed in other settings.

Random versus blocked practice in treatment for childhood apraxia of speech

PURPOSE

To compare the relative effects of random vs. blocked practice schedules in treatment for childhood apraxia of speech (CAS). Although there have been repeated suggestions in the literature to use random practice in CAS treatment, no systematic studies exist that have directly compared random with blocked practice in this population.

METHOD

Using an alternating treatments single-subject design with multiple baselines across behaviors, the authors compared random and blocked practice in 4 children diagnosed with CAS in terms of retention and transfer. Random and blocked practice were implemented in the context of a version of Dynamic Temporal and Tactile *Cueing treatment (Strand, Stoeckel, & Baas, 2006). Perceptual accuracy of target utterances was scored, and effect sizes were calculated to quantify the magnitude of treatment effects.

RESULTS

Findings were mixed, with 2 children showing a blocked practice advantage, 1 child showing a random practice advantage, and 1 child showing no clear improvement in either condition.

CONCLUSIONS

These findings suggest that the random practice advantage observed in the nonspeech motor learning literature may not extend to treatment for CAS. Furthermore, the findings add to the small body of literature indicating that integral stimulation treatment can lead to improvements in speech production for children with CAS.

Specificity and variability of practice, and contextual interference in acquisition and transfer of an underhand volleyball serve

The present study investigated the effects of practice composition on acquisition and transfer of the underhand volleyball serve in a standard high school physical education setting. 72 middle-school students (M age = 14.1 yr., SD = 0.7) were selected and assigned to six groups: five experimental (Random, Serial, Blocked, Constant, Specific), and one Control group all pretested. The five experimental groups received 45 acquisition trials over three class periods. Directional quantitative knowledge of results was provided to the students after each trial. After a 72-hr. retention interval, all groups performed 15 underhand volleyball serves without knowledge of results. Analyses indicated (a) better acquisition in the Specific and Constant groups relative to the Serial, Random, and Blocked groups, and (b) significantly superior transfer performance in the Specific and Random groups relative to the Serial, Blocked, Constant, and Control groups. This provides partial support for specificity of learning and contextual interference hypotheses. Practice in accord with the contextual interference hypothesis permits differentiations among varied practice schedules only during transfer.

High Levels of Contextual Interference Enhance Handwriting Skill Acquisition

The authors conducted 3 experiments to examine whether introducing high levels of contextual interference is useful in handwriting skill acquisition. For all experiments, elementary school students (Ns = 44, 50, and 78, respectively) were randomly assigned to 1 of 2 practice schedules-blocked or random practice-in the acquisition phase. In the blocked condition, each of 3 letters (h, a, and y) or (in Experiment 1) symbols was handwritten 24 times consecutively. In the random condition, each letter (or symbol) was practiced 24 times, but in an intermixed, unsystematic sequence. Overall, the results showed that the random practice schedule leads to enhanced retention and transfer performance of handwriting skill acquisition.

Effects of cognitive processes and task complexity on acquisition, retention, and transfer of motor skills

This experiment was designed to investigate the effect of cognitive problem-solving operations (termed contextual interference) and complexity of tasks on the acquisition retention and transfer of motor skills. Ninety-six children, ages 7.5-9.5 practiced the task of throwing beanbags under either low contextual interference (blocked practice), high contextual interference (random practice) or medium contextual interference (combined practice). Half of the participants acquired a complex task and the other half a simple task. All participants performed 30 acquisition trials, 9 retention trials and 4 transfer trials. Results indicated that participants who practiced in the blocked practice group did not differ in their performance whether they acquired complex or simple tasks. On the other hand, participants from the random and combined practice groups who acquired simple tasks performed better than those who acquired complex tasks. These findings support the hypothesis that there is a limit to the interference during practice that will benefit retention and transfer, thus creating the contextual interference effect. It seems that the complex-task condition combined with random or combined practice schedule increased the difficulty of acquisition, possibly impeding the cognitive processing during acquisition, thus impairing the learning process.

Effects of Cognitive Processes and Task Complexity on Acquisition, Retention, and Transfer of Motor Skills

This experiment was designed to investigate the effect of cognitive problem-solving operations (termed contextual interference) and complexity of tasks on the acquisition retention and transfer of motor skills. Ninety-six children, ages 7.5-9.5 practised the task of throwing beanbags under either low contextual interference (blocked practice), high contextual interference (random practice) or medium contextual interference (combined practice). Half of the participants acquired a complex task and the other half a simple task. All participants performed 30 acquisition trials, 9 retention trials and 4 transfer trials. Results indicated that participants who practised in the blocked practice group did not differ in their performance whether they acquired complex or simple tasks. On the other hand, participants from the random and combined practice groups who acquired simple tasks performed better than those who acquired complex tasks. These findings support the hypothesis that there is a limit to the interference during practice that will benefit retention and transfer, thus creating the contextual interference effect. It seems that the complex-task condition combined with random or combined practice schedule increased the difficulty of acquisition, possibly impeding the cognitive processing during acquisition, thus impairing the learning process.

Variability effects on retention of a motor skill in elementary school children

Variability effects on learning, retention, and transfer of motor skills have been a main issue for scientists involved in laboratory and field research. Variable practice is intended as parameter variations of a generalized motor program as well as rehearsal of different motor programs. Although the benefits deriving from variable practice on motor skill retention appear quite robust in laboratory settings, field investigations have produced mixed results. Hence, the aim of this study was to examine the effects of different variable schedules on the retention of a complex min tor skill in a physical education setting. 61 elementary school children were assigned Blocked/Nonvariable, Blocked/Variable, Serial/Nonvariable, or Serial/Variable schedules, and practiced two tasks (throwing and hurdle running) and a complex skill (jumping) across 14 lessons. Improved performance in the complex skill was found after practice, with the Serial/Nonvariable group outperforming all other groups. Therefore. the rehearsal of different motor programs was beneficial for jumping skill retention, whereas parameter variation was not.

Effects of contextual interference and age on acquisition, retention, and transfer of motor skill

This experiment was designed to investigate the varying conditions of contextual interference within three age groups. 40 5-yr.-olds, 40 7-yr.-olds, and 40 11-yr.-olds practiced the task of throwing beanbags under either low contextual interference (blocked practice), high contextual interference (random practice), or medium contextual interference (combined practice). All subjects performed 30 acquisition trials, 12 retention trials and 6 transfer trials. Analysis indicated that only the 7-yr.-old subjects differed in their performance in the various practice groups. As hypothesized and suggested by developmental theories, the combined and blocked practice groups acquired the task better. On the other hand, the 5- and 11-yr.-olds did not differ in performance in the different practice groups. Whether this is associated with difficulty of the task or the length of practice can be assessed in further study. Contextual interference in different age groups needs further investigation.

Dissociated contextual interference effects in children and adults

24 7-yr.-old children and 24 university-age adults practiced a ballistic aiming task under either low contextual interference (blocked practice) or high contextual interference (random practice). All subjects performed 90 acquisition trials, followed by 20 transfer trials and 15 retention trials. Similar to previous findings, the adults performed the acquisition trials better under blocked than under random conditions, yet performed the retention and transfer tests better after random than blocked practice. No differences in acquisition were found between blocked and random practice conditions for the children; nevertheless, the random group performed the retention and transfer tests better than the blocked group. The results are discussed in relation to applied and theoretical issues of contextual interference.

Practice schedule effects on the performance and learning of low- and high-skilled students: an applied study

This study examined the effects of practice schedule manipulations implemented in an instructional setting on the performance and learning of low- and high-skilled students. College undergraduates (N = 83) enrolled in 5 tennis classes completed a pretest on the forehand and backhand ground strokes, practiced these skills under a blocked or alternating schedule, and then completed a posttest. Results indicated that practice schedule effects on learning were influenced by student ability. Low-skilled students assigned to the blocked schedule had higher posttest scores than those assigned to the alternating schedule, whereas no significant differences were found for high-skilled students. These findings are discussed in relation to previous applied and laboratory-based findings and as a means for manipulating practice difficulty in teaching physical education.

The influence of proficiency level, transfer distality, and gender on the contextual interference effect

This study examined the impact of high and low proficiency level, transfer distality, and gender on the contextual interference effect with an open skill. Subjects were separated into two levels of proficiency based on performance on a pretest similar to the experimental task. Analysis of error scores during acquisition indicated that the partitioning of subjects according to ability level had been successful. Transfer distality was varied by presenting subjects with two tasks varying in similarity to the acquisition task. Analysis of absolute constant, constant, variable, and total error scores in transfer strongly suggested that subjects' consistency rather than response bias was affected by the experimental variables. The findings suggested that, for the task used in this study, proficiency level does not account for gender differences in the contextual interference effect, as the effect was only reliably found for females. For coincident timing skills, it appears that there may be two distinct conclusions drawn from the results of this study: contextual interference only benefits female subjects' consistency and the effect of contextual interference increases with the distality of transfer, regardless of the subjects' proficiency level.

Effects of contextual interference on learning technical sports skills

The effects of contextual interference on learning skills of volleyball (volley, bump, serve) are influenced by the scheduling of actual practice sessions: the activities can be proposed in a repetitive practice schedule (blocked practice) by continuously repeating the same task (low interference) or in random practice schedules by performing more tasks or variations of one same activity (high interference). High contextual interference, even though causing immediate limited performance, leads to superior performance on retention and transfer tests. Four experimental groups (13 students each) were placed in conditions of random, blocked, serial, and serial with high interference practice for 8 meetings (2 tests and 6 practice). Analysis yielded significant differences among the groups on a transfer test (long transfer) for the serve, so results in this instructional setting are partially in line with those generally found in laboratory experiments.