Effects of contextual interference on learning technical sports skills

High contextual interference improves retention in motor learning: systematic review and meta-analysis

The effect of practice schedule on retention and transfer has been studied since the first publication on contextual interference (CI) in 1966. However, strongly advocated by scientists and practitioners, the CI effect also aroused some doubts. Therefore, our objective was to review the existing literature on CI and to determine how it affects retention in motor learning. We found 1255 articles in the following databases: Scopus, EBSCO, Web of Science, PsycINFO, ScienceDirect, supplemented by the Google Scholar search engine. We screened full texts of 294 studies, of which 54 were included in the meta-analysis. In the meta-analyses, two different models were applied, i.e., a three-level mixed model and random-effects model with averaged effect sizes from single studies. According to both analyses, high CI has a medium beneficial effect on the whole population. These effects were statistically significant. We found that the random practice schedule in laboratory settings effectively improved motor skills retention. On the contrary, in the applied setting, the beneficial effect of random practice on the retention was almost negligible. The random schedule was more beneficial for retention in older adults (large effect size) and in adults (medium effect size). In young participants, the pooled effect size was negligible and statically insignificant.

The learning of sprint hurdles: A comparative study on increasing contextual interference and blocked practice schedules

The contextual interference (CI) approach has proposed that a random order of practice for motor skills is superior in facilitating learning compared to a blocked arrangement of practice trials. Two groups of physical education students learned sprint hurdles, employing either an increasing CI practice schedule (n = 23) or a blocked practice schedule (n = 23). In both the practice schedules, the same exercises were used in a different trial order during each learning session. Eleven practice sessions were conducted over a period of six weeks, with two days of practice per week. Ten and 40 days after the acquisition phase, a retention and transfer test were conducted. The results showed no differences between the two practice schedules during the retention tests. However, students practicing with an increasing CI arrangement performed better on the delayed transfer test compared to students which practiced with a blocked schedule. Specifically, the increasing CI group more effectively (p < 0.05) cleared the hurdles due to a lower take-off step angle and longer step length than the blocked practice group. Although utilizing an increase in CI during the learning phase of sprint hurdling produced more persistent learning effects relative to a traditional blocked practice schedule for adult novice learners, further research is warranted to explore the CI effect across a broader range of sport skills.

Resonance Effects in Variable Practice for Handball, Basketball, and Volleyball Skills: A Study on Contextual Interference and Differential Learning

Effective sports training should be attuned to the athlete's specific conditionings and characteristics. In motor learning research, two often neglected factors that influence this resonance are the learner's athletic background and the structural diversity of exercises (e.g., relative similarity). In the setting of real-word training with higher external validity, this study examines the effects of three learning approaches (i.e., contextual interference (CI), differential learning (DL), and free-play control condition (CO)) on the parallel learning of handball (HB), volleyball (VB), and basketball (BB) skills, considering participants' prior sport backgrounds. Forty-five males (15 HB, 15 VB, and 15 BB players) with a mean age of 22 ± 1.4 years and at least 6 years of experience in the mastered discipline voluntarily participated in this study. A pre-post-retention test design including a 6-week-intervention program was employed. During the intervention period, participants engaged in three training sessions a week, with each one lasting approximately 80 min. Each of the three test sessions involved the execution of ten attempts of BB free-throw shooting, HB three-step goal throwing, and VB underarm passing following a blocked order. In terms of short-term (pre-post) gain, only the DL group significantly improved their performance in both non-mastered disciplines (p = 0.03, ES = 1.58 for the BB free-throw and p = 0.05, ES = 0.9 for the HB shooting tests), with a trend (ES = 0.53) towards an improvement in the performance of the mastered VB underarm-pass skill. In terms of relatively permanent gains, the CI group significantly improved their performances from pre- to retention test only in the non-mastered BB free-throw skill (p = 0.018, ES = 1.17). In contrast, the DL group significantly improved their performance at retention compared to the pre-test in both non-mastered BB (p = 0.004, ES = 1.65) and HB (p = 0.003, ES = 2.15) skills, with a trend (ES = 0.4) towards improvement in the mastered VB test. In both the short-term and relatively long-term, higher composite score gains were observed in DL compared to CI (p = 0.006, ES = 1.11 and 0.049, ES = 1.01) and CO (p = 0.001, ES = 1.73 and <0.0001, ES = 2.67). In conclusion, the present findings provide additional support for the potential advantages of the DL model over those of CI. These findings can serve as the basis for tailored training and intervention strategies and provide a new perspective for addressing various issues related to individual and situational learning.

The role of lag effect in distributed practice on learning novel vocabulary

PURPOSE

The purpose of the current study was to investigate the lag effects in two different versions of distributed practice on learning novel language vocabulary.

METHOD

Forty-four healthy monolingual English-speaking participants were randomly assigned to two versions of distributed practice. The two versions of distributed practice were created by altering the temporal lag between the practice sessions. Participants in both groups completed a similar practice regimen wherein they practiced 30 French occupations five times each for a total of 150 times. The pre/post-design employed in this experiment involved participants completing baseline, immediate, and delayed retention tests. The outcome measures included a comprehensive multiple-choice test and a written expression task.

RESULTS

The findings from the comprehensive and expressive tasks indicated that the learning performance of participants across both groups was better during the immediate retention test compared to the delayed retention test. With regard to the group, participants assigned to the condensed version of distributed practice demonstrated superior learning of the novel vocabulary over participants assigned to the extended version of distributed practice.

CONCLUSION

The findings indicate that an increased temporal lag between the practice sessions results in a "non-monotonic function," wherein the learning continues to improve until an optimal lag, after which the learning declines as the lag continues to increase. This line of research will have a substantive impact on service-delivery models in speech-language pathology.

Error-based and reinforcement learning in basketball free throw shooting

This study investigates the effects of error-based and reinforcement training on the acquisition and long-term retention of free throw accuracy in basketball. Sixty participants were divided into four groups (n = 15 per group): (i) the error-based group (sensory feedback), (ii) the reinforcement group (binary feedback including success or failure), (iii) the mixed group (sensory feedback followed by binary feedback), and (iv) the control group (without training). Free throws success was recorded before training (PreT), immediately after (Postd0), one day later (Postd1), and seven days later (Postd7). The error-based group, but not the reinforcement group, showed a significant immediate improvement in free throw accuracy (PreT vs Postd0). Interestingly, over time (Postd0 vs Postd1 vs Postd7), the reinforcement group significantly improved its accuracy, while the error-based group decreased it, returning to the PreT level (PreT vs Post7). The mixed group showed the advantage of both training methods, i.e., fast acquisition and retention on a long-term scale. Error-based learning leads to better acquisition, while reinforcement learning leads to better retention. Therefore, the combination of both types of learning is more efficient for both acquisition and retention processes. These findings provide new insight into the acquisition and retention of a fundamental basketball skill in free throw shooting.

A comparison of perceptual anticipation in combat sports between experts and non-experts: A systematic review and meta-analysis

In order to systematically evaluate perceptual anticipation between experts and non-experts for different kinds of combat sports, we needed to perform a comprehensive assessment. In this systematic review and meta-analysis, we searched four English-language and three Chinese-language databases that used expert/non-expert research paradigms, to explore perceptual anticipation in combat sports. We employed a random effects model for pooled analyses using the inverse variance method. We included 27 eligible studies involving 233 datasets in this meta-analysis. We observed large effect sizes for the differences between experts and non-experts in both response accuracy (1.51; 95% CI: 1.15 to 1.87, p < 0.05) and reaction time (-0.91; 95% CI: −1.08 to−0.73, p < 0.05). We also observed substantial differences between experts and non-experts in the mean duration of visual fixations per trial (1.51; 95% CI: −2.40 to −0.63, p < 0.05), but not in the visual fixation duration (0.16; −061 to 0.92, p = 0.69). Taken together, high-level combat athletes have more advantages in perceptual anticipation than lower-level athletes, showing faster and more accurate responses when facing the opponent's attacks, as well as focusing on fewer points of visual fixations than novice athletes. Different types of combat sports and stimulus presentations affect perceptual anticipation abilities to varying extents in relation to outcome measures, with more pronounced expertise in a stimulus that is closer to real-world situations.

Learning Multiple Movements in Parallel-Accurately and in Random Order, or Each with Added Noise?

Traditionally, studies on learning have mainly focused on the acquisition and stabilization of only single movement tasks. In everyday life and in sports, however, several new skills often must be learned in parallel. The extent to which the similarity of the movements or the order in which they are learned influences success has only recently begun to attract increased interest. This study aimed to compare the effects of CI in random practice order (high CI) with differential learning (DL) in learning three volleyball skills in parallel. Thirty-two advanced beginners in volleyball (mean age = 24, SD = 2.7) voluntarily participated in the study. Within a pre-, post-, retention test design, an intervention of six weeks and one week retention phase, the effects of three practice protocols of a CI, DL, and control (CO) group were compared. Three different volleyball skills (underhand pass, overhand pass, and overhand serve) were trained with emphasis on accuracy. Results showed statistically significant higher rates of improvement in the acquisition and learning phases for the DL group compared to the CI and CO groups. The differences were associated with moderate to high effect sizes in all individual skills and in the combined skills. The findings show more agreement with DL than with CI theory.

Promoting Children's Psychomotor Development with Multi-Teaching Didactics

This group randomized control trial examined the dose-response effect of varied combinations of linear and nonlinear pedagogy (enriched physical education with specific program led by specialist vs. conventional physical education led by generalist) for improving first-grade children's motor creativity, executive functions, self-efficacy, and learning enjoyment. We led three physical education classes per group through 12 weeks of combined instruction, based on linear and nonlinear pedagogy: mostly linear (ML; 80% linear, 20% nonlinear; n = 62); mostly nonlinear (MNL; 20% linear, 80% nonlinear; n = 61); and control (C; conventional teaching from generalists; n = 60). MNL improved in (a) motor creativity ability (DMA; 48.7%, 76.5%, and 47.6% for locomotor, stability, and manipulative tasks, respectively); (b) executive functions (working memory and inhibitory control) for RNG task (14.7%) and task errors (70.8%); (c) self-efficacy (5.9%); and (d) enjoyment (8.3%). In ML, DMA improved by 18.0% in locomotor and 60.9% in manipulative tasks. C improved of 10.5% in enjoyment, and RNG task worsened by 22.6%. MNL improvements in DMA tasks, executive functions, and self-efficacy were significantly better than those in C. ML was better than C in DMA task and in executive functions' task errors. Overall, ML and MNL approaches were more effective than conventional generalist teaching (C), and the MNL combination of 80% nonlinear and 20% linear pedagogy was optimal. We recommend that educators favor the MNL approach.

Effects of Varied Practice Approach in Physical Education Teaching on Inhibitory Control and Reaction Time in Preadolescents

This study aimed to investigate the effects of nonlinear and linear varied practice compared to a constant linear practice on inhibitory control and reaction time, which are capacities that involve cognition in preadolescents. Eighty-three participants in the 8th grade participated in the study. They were assigned to two experimental groups (varied practice), taught using nonlinear pedagogy (NLP) and linear pedagogy (VLP), respectively, or one control group (constant practice), taught using linear pedagogy (CLP). All participants were tested for inhibitory control (congruent and incongruent conditions) and simple reaction time. Overall, varied practice (both linear and nonlinear) induced larger improvements than constant practice under both congruent (p = 0.026) and incongruent (p = 0.013) conditions of inhibitory control. Additionally, VLP provided greater improvements in inhibitory control (for the incongruent condition) than NLP and CLP. Although NLP and VLP may be preferable to CLP approaches for enhancing executive functions in preadolescents, VLP seems to be the most effective approach aimed to improve cognition within PE classes.

Repetition without Repetition or Differential Learning of Multiple Techniques in Volleyball?

A variety of approaches have been proposed for teaching several volleyball techniques to beginners, ranging from general ball familiarization to model-oriented repetition to highly variable learning. This study compared the effects of acquiring three volleyball techniques in parallel with three approaches. Female secondary school students (N = 42; 15.6 ± 0.54 years) participated in a pretest for three different volleyball techniques (underhand pass, overhand pass, and overhead serve) with an emphasis on accuracy. Based on their results, they were parallelized into three practice protocols, a repetitive learning group (RG), a differential learning group (DG), and a control group (CG). After a period of six weeks with 12 intervention sessions, all participants attended a posttest. An additional retention test after two weeks revealed a statistically significant difference between DG, RG, and CG for all single techniques as well as the combined multiple technique. In each technique-the overhand pass, the underhand pass, the overhand service, and the combination of the three techniques-DG performed best (each p < 0.001).

Sports in time of COVID-19: Impact of the lockdown on team activity

The COVID-19 pandemic has affected many sectors of our global society since its detection in Wuhan in December 2019, and team sports have been no stranger to this reality. This special article presents a review of the literature exposing the dangers for athletes of this virus, reporting the effects of the pandemic on competitive sport, and making evidence-based recommendations to avoid the consequences of detraining in confined athletes. Furthermore, we present the results of a survey with 361 answers computed from coaches and different staff members from 26 different countries, representing the activity of more than 4500 athletes from all over the world. The aim was to know more teams’ activity during this cessation period. Finally, the article outlines recommendations based on the answers to help teams if a second outbreak of the virus forces massive confinements again, guiding a safe return to sport at any competitive level.

What Is the Level of Contextual Interference in Serial Practice? A Meta-Analytic Review

For over 40 years, the contextual interference effect in motor learning has been investigated. While the difference between levels of contextual interference experienced under blocked and random practice are well established, the difference in the levels of contextual interference experienced under serial and random practice is still ambiguous. Therefore, a meta-analytic review was conducted to clarify this inconsistency. We focused on one question: Do random practice and serial practice have the same effect on motor learning? ISI Web of Science, PubMed, and Scopus database were searched. Nine studies were included. The results of our meta-analyses show that serial and random practices present the same results in terms of performance in retention and transfer tests. This result is aligned to the original finding of the contextual interference effect, as well as its explanatory hypotheses. In addition, a complementary explanation in defense of the same mechanisms operating in serial and random practices is discussed. In conclusion, our results suggest that serial practice present high contextual interference.

Role of Massed Versus Distributed Practice in Learning Novel Foreign Language Utterances

The current study compared the role of massed versus distributed practice in learning novel foreign language utterances. Fifty healthy native English-speaking participants were randomly assigned to either massed or distributed practice groups. All participants practiced eight novel French utterances 25 times each for a total of 200 times, with the spacing of practice sessions differing between the two groups. Both the groups completed an immediate retention as well as a delayed retention test. Participants' learning was evaluated based on phonetic accuracy and naturalness of the French utterances. The findings revealed that participants involved in distributed practice demonstrated better learning over participants involved in massed practice. Future research should aim to extrapolate these findings in treating speech disorders.

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.

Enhancing technical skill learning through interleaved mixed-model observational practice

A broad foundation of behavioural (Hayes et al. in Exp Brain Res 204(2): 199-206, 2010) and neurophysiological (Kohler et al. in Science 297(5582): 846-848, 2002) evidence has revealed that the acquisition of psychomotor skills, including those germane to clinical practice (Domuracki et al. in Med Educ 49(2): 186-192, 2015), can be facilitated through observational practice. Interestingly, research also reveals that learning via observation is greatest when the learner has the opportunity to view both error-free expert demonstrations and flawed novice demonstrations (Rohbanfard and Proteau in Exp Brain Res 215: 183-197, 2011). In this study, we explored whether the learning that results from the combined viewing of experts and novices is greater when the demonstrations are presented under observation schedules characterized by higher levels of contextual interference. To do so, we engaged participants in an observational learning study of the Fundamentals of Laparoscopic Surgery pots-and-beans task: a simulated procedure in which performers must move objects under precision constraints in the minimal access surgery environment. Each participant was randomized to one of three groups that engaged in identical physical and mixed-model observational practice of this skill, with the only difference being that one group's observation was presented in blocked fashion (low interference) while the other two groups' observations were presented in semi-interleaved (medium interference) and interleaved (high interference) fashions. Total errors and time-to-complete measures taken during physical practice blocks revealed that all three groups improved over the intervention. Further analyses revealed that the low interference group performed better immediately following the physical and observational practice intervention, but that the medium- and high-interference groups were conveyed a performance advantage in a transfer test conducted after a period of retention that challenged participants to perform in the opposite direction. The results are discussed with respect to the classic contextual interference effect (Shea and Morgan in J Exp Psychol 5(2): 179-187, 1979) and with particular relevance to clinical skills education.

Role of Constant, Random and Blocked Practice in an Electromyography-Based Oral Motor Learning Task

PURPOSE

The role of principles of motor learning (PMLs) in speech has received much attention in the past decade. Oral motor learning, however, has not received similar consideration. This study evaluated the role of three practice conditions in an oral motor tracking task.

METHOD

Forty-five healthy adult participants were randomly and equally assigned to one of three practice conditions (constant, blocked, and random) and participated in an electromyography-based task. The study consisted of four sessions, at one session a day for four consecutive days. The first three days sessions included a practice phase, with immediate visual feedback, and an immediate retention phase, without visual feedback. The fourth session did not include practice, but only delayed retention testing, lasting 10-15 minutes, without visual feedback.

RESULTS

Random group participants performed better than participants in constant and blocked practice conditions on all the four days. Constant group participants demonstrated superior learning over blocked group participants only on day 4.

CONCLUSION

Findings indicate that random practice facilitates oral motor learning, which is in line with limb/speech motor learning literature. Future research should systematically investigate the outcomes of random practice as a function of different oral and speech-based tasks.

No Overt Effects of a 6-Week Exergame Training on Sensorimotor and Cognitive Function in Older Adults. A Preliminary Investigation

Several studies investigating the relationship between physical activity and cognition showed that exercise interventions might have beneficial effects on working memory, executive functions as well as motor fitness in old adults. Recently, movement based video games (exergames) have been introduced to have the capability to improve cognitive function in older adults. Healthy aging is associated with a loss of cognitive, as well as sensorimotor functions. During exergaming, participants are required to perform physical activities while being simultaneously surrounded by a cognitively challenging environment. However, only little is known about the impact of exergame training interventions on a broad range of motor, sensory, and cognitive skills. Therefore, the present study aims at investigating the effects of an exergame training over 6 weeks on cognitive, motor, and sensory functions in healthy old participants. For this purpose, 30 neurologically healthy older adults were randomly assigned to either an experimental (ETG, n = 15, 1 h training, twice a week) or a control group (NTG, n = 15, no training). Several cognitive tests were performed before and after exergaming in order to capture potential training-induced effects on processing speed as well as on executive functions. To measure the impact of exergaming on sensorimotor performance, a test battery consisting of pinch and grip force of the hand, tactile acuity, eye-hand coordination, flexibility, reaction time, coordination, and static balance were additionally performed. While we observed significant improvements in the trained exergame (mainly in tasks that required a high load of coordinative abilities), these gains did not result in differential performance improvements when comparing ETG and NTG. The only exergaming-induced difference was a superior behavioral gain in fine motor skills of the left hand in ETG compared to NTG. In an exploratory analysis, within-group comparison revealed improvements in sensorimotor and cognitive tasks (ETG) while NTG only showed an improvement in a static balance test. Taken together, the present study indicates that even though exergames might improve gaming performance, our behavioral assessment was probably not sensitive enough to capture exergaming-induced improvements. Hence, we suggest to use more tailored outcome measures in future studies to assess potential exergaming-induced changes.

Contextual Interference Effect on Acquisition and Retention of Pistol-Shooting Skills

The effects of contextual interference on learning pistol-shooting skills in a natural training environment were examined. The shooting skills consisted of three “stages” with different requirements for the skill variations commonly used in the field. 12 participants were randomly assigned into one of two practice conditions, blocked vs serial. Following a 20-min. safety and skill instructional session, Blocked group practiced 10 trials in a row at each stage, while Serial group performed 5 trials in a row for each of the three stages and then repeated the cycle. Both groups completed a total of 30 practice trials over the three stages. A 10-min. rest interval was provided prior to a retention test which included 9 trials (3 trials at each stage in a blocked format). Results based on the data of Stage III, the most complex skill among the three stages, showed a pattern consistent with previous findings that practicing in the serial schedule depressed performance during initial training but maintained the performance better at retention, relative to the blocked practice.

Effects of Contextual Interference on Acquisition and Retention of Three Volleyball Skills

Manipulating the organization of practice conditions, through contextual interference, was identified as a method to promote motor skill acquisition by Brady in 1998. The generalizability of this learning effect is questionable and the amount of repetition versus the amount of change in task presentation requires investigation. The purpose of this study was to explore explanations for the performance of learners practicing the AAHPERD volleyball skills test when the change in task presentation varied. High school students were randomly assigned to blocked, random, and random-blocked practice groups. While all groups significantly improved all skills during acquisition, there was no support for the contextual interference effect. Potential explanations might be dependent upon the learners' skill and the complexity of the task to be learned. Further research is warranted examining contextual interference effect on practice organization at levels of difficulty appropriate to facilitate cognitive processing of task-related information.

Contextual Interference: A Meta-Analytic Study

A meta-analysis of the contextual interference effect produced 139 estimates of effect sizes from 61 studies. The average overall effect size was .38. The effect size for basic research (.57) was significantly different from applied research (.19). Significant differences were also obtained between the effect sizes for adults (.50) and those for younger learners (.10). Power for retention and transfer scores was not significantly different. The overall mean power of the studies reviewed was .43.

Enhancing astronaut performance using sensorimotor adaptability training

Astronauts experience disturbances in balance and gait function when they return to Earth. The highly plastic human brain enables individuals to modify their behavior to match the prevailing environment. Subjects participating in specially designed variable sensory challenge training programs can enhance their ability to rapidly adapt to novel sensory situations. This is useful in our application because we aim to train astronauts to rapidly formulate effective strategies to cope with the balance and locomotor challenges associated with new gravitational environments—enhancing their ability to “learn to learn.” We do this by coupling various combinations of sensorimotor challenges with treadmill walking. A unique training system has been developed that is comprised of a treadmill mounted on a motion base to produce movement of the support surface during walking. This system provides challenges to gait stability. Additional sensory variation and challenge are imposed with a virtual visual scene that presents subjects with various combinations of discordant visual information during treadmill walking. This experience allows them to practice resolving challenging and conflicting novel sensory information to improve their ability to adapt rapidly. Information obtained from this work will inform the design of the next generation of sensorimotor countermeasures for astronauts.

Effects of variability of practice in music: a pilot study on fast goal-directed movements in pianists

Variability of Practice (VOP) refers to the acquisition of a particular target movement by practicing a range of varying targets rather than by focusing on fixed repetitions of the target only. VOP has been demonstrated to have beneficial effects on transfer to a novel task and on skill consolidation. This study extends the line of research to musical practice. In a task resembling a barrier-knockdown paradigm, 36 music students trained to perform a wide left-hand interval leap on the piano. Performance at the target distance was tested before and after a 30-min standardized training session. The high-variability group (VAR) practiced four different intervals including the target. Another group (FIX) practiced the target interval only. A third group (SPA) performed spaced practice on the target only, interweaving with periods of not playing. Transfer was tested by introducing an interval novel to either group. After a 24-h period with no further exposure to the instrument, performance was retested. All groups performed at comparable error levels before training, after training, and after the retention (RET) interval. At transfer, however, the FIX group, unlike the other groups, committed significantly more errors than in the target task. After the RET period, the effect was washed out for the FIX group but then was present for VAR. Thus, the results provide only partial support for the VOP hypothesis for the given setting. Additional exploratory observations suggest tentative benefits of VOP regarding execution speed, loudness, and performance confidence. We derive specific hypotheses and specific recommendations regarding sample selection and intervention duration for future investigations. Furthermore, the proposed leap task measurement is shown to be (a) robust enough to serve as a standard framework for studies in the music domain, yet (b) versatile enough to allow for a wide range of designs not previously investigated for music on a standardized basis.

Contextual interference effects on the acquisition of skill and strength of the bench press

The purpose of this study was to investigate contextual interference effects on skill acquisition and strength gains during the learning of the bench press movement. Twenty-four healthy, college-aged males and females were stratified to control, high contextual interference (HCI), and low contextual interference (LCI) groups. Treatment groups were provided with written and visual instruction on proper bench press form and practiced the bench press and dart throwing for four weeks. Within each session, LCI performed all bench press sets before undertaking dart-throws. HCI undertook dart-throws immediately following each set of bench press. Control only did testing. Measurements, including one repetition maximum (1RM), checklist scores based on video recordings of participants' 1RM's, and dart-throw test scores were taken at pre-test, 1 week, 2 week, post-test, and retention test. Results were consistent with the basic premise of the contextual interference effect. LCI had significant improvements in percent 1RM and checklist scores during training, but were mostly absent after training (post-test and retention test). HCI had significant improvements in percent 1RM and checklist scores both during and after training. Thus, HCI may augment strength and movement skill on the bench press since proper technique is an important component of resistance exercise movements.

Task characteristics and the contextual interference effect

The purpose of this exploratory study was to examine the influence of blocked and random practice on the acquisition and retention of a criterion multisegment motor task practiced alongside either two similar-distractors tasks or two different-distractors tasks. The random-practice similar-distractors group made more decision-making errors and performed the criterion task more slowly than the blocked-practice similar-distractors group during the acquisition phase. Following a brief filled retention interval, the blocked-practice similar-distractors group demonstrated a loss of acquired performance capabilities, whereas the random-practice similar-distractors group did not. The blocked- and random-practice different-distractors groups performed similarly throughout the experiment. Results are interpreted within Glenberg's component-levels theory, in which it was argued that random practice must stimulate the differential storage of multilevel contextual components associated with the multiple motor tasks being learned to produce a contextual interference effect. The theoretical and practical implications of differential storage versus nonrepetition as a function of random practice are discussed.

Chunking and compound cueing of movement sequences: learning, retention, and transfer

When teaching a complex sequence, the sequence is often chunked into components; however, this strategy may not always benefit learning, but may be detrimental. The hypothesis is that this occurs because chunking deprives learners of compound cues that could aid recall. To test this, participants learned 9-item movement sequences, either as three 3-item chunks or as one 9-item series. To undermine compound cueing, some sequences had several movements in common. Learning a sequence in chunks impaired motor skill acquisition only when participants could have exploited compound cues; it also led participants to adopt an alternative recall strategy, which transferred to novel sequences even though this was detrimental to recall.

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.

Blocked and Random Practice Organization in the Learning of Rhythmic Dance Step Sequences

This study investigated the role played by Blocked (low contextual interference) and Random (high contextual interference) schedules in the acquisition of rhythmic footstep sequences by adolescent females ( N = 40, M age = 15.8 yr., SD = 1.3). After a baseline assessment (T0), motor learning was assessed after six sessions (T1) in terms of the participants' ability to reproduce the step sequences using visual and auditory guidance. A retention test (T2) also occurred 21 days after T1. Analysis of variance yielded significant main effects of group, test, and an interaction. Both groups improved performance from T0 to T1, but the Blocked schedule group outperformed the Random schedule group at T2. Significant group differences were not observed at T2. The Random schedule group's performance did not significantly change from T1 to T2, and the Blocked schedule group's performance significantly decreased. Apparently, the learning of rhythmic footstep dance sequences was not influenced by practice organization.

Contextual interference effects in learning volleyball skills

The aim of this study was to examine the contextual interference effect on learning three volleyball skills. Participants were 26 novice female volleyball players (M age= 12.4 yr., SD= 1.2). They were assigned into two groups, Low Interference (n = 13) and High Interference (n = 13). Two practice schedules were used: blocked (Low Interference) and random (High Interference). The training period lasted for 10 weeks and included 2 training sessions of 75 min. each per week. The pretest was performed before the first training session, the posttest was performed after the completion of the last training period, and the retention test was performed two weeks after the posttest. A 2 (Groups) x 3 (Measurement Periods) analysis of variance with repeated measures indicated significant improvement in performance between pre- and posttests for both High Interference and Low Interference groups for the three skills included in this study. There was no significant main effect of group or interaction effect of group and measure. These findings suggest that either blocked or random practice could be effectively used in learning of volleyball skills by unskilled children.

Variable practice with lenses improves visuo-motor plasticity

Novel sensorimotor situations present a unique challenge to an individual's adaptive ability. Using the simple and easily measured paradigm of visual-motor rearrangement created by the use of visual displacement lenses, we sought to determine whether an individual's ability to adapt to visuo-motor discordance could be improved through training. Subjects threw small balls at a stationary target during a 3-week practice regimen involving repeated exposure to one set of lenses in block practice (x 2.0 magnifying lenses), multiple sets of lenses in variable practice (x 2.0 magnifying, x 0.5 minifying and up-down reversing lenses) or sham lenses. At the end of training, adaptation to a novel visuo-motor situation (20-degree right shift lenses) was tested. We found that (1) training with variable practice can increase adaptability to a novel visuo-motor situation, (2) increased adaptability is retained for at least 1 month and is transferable to further novel visuo-motor permutations and (3) variable practice improves performance of a simple motor task even in the undisturbed state. These results have implications for the design of clinical rehabilitation programs and countermeasures to enhance astronaut adaptability, facilitating adaptive transitions between gravitational environments.

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.

The contextual interference effect in acquisition of dart-throwing skill tested on a transfer test with extended trials

Previous studies of contextual interference have shown that practicing several motor skills randomly (high contextual interference) facilitates retention and transfer in comparison to practicing the same tasks in a blocked order (low contextual interference). However, many studies have not supported this phenomenon in motor learning, and some researchers have questioned whether the effect can be tested by using only a few trials on the transfer test. The present study used a different methodological approach in which the number of test trials was increased to assess whether the contextual interference effect is sustained over an extended number of trials in the transfer phase. Undergraduate students (N=32) were randomly allocated to either a blocked or random group. The participants practiced 80 acquisition trials in the dart-throwing task from distances of 300 cm and 420 cm, using two different grips. The transfer test after a 10-min. interval consisted of 40 trials with a new grip at a distance of 360 cm. The results did not support the contextual interference effect since there were no significant differences between groups on transfer. These findings suggest that the contextual interference effect may not be a global learning phenomenon which can be generalized to all learning situations.

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.