Search Results

You are looking at 11 - 20 of 762 items for :

  • "complexity" x
Clear All
Restricted access

Tami Abourezk and Tonya Toole

Thirty-four women ages 60 to 75 years were divided into two groups based on self-reported physical activity levels. The presence of significant fitness differences between the two activity groups was confirmed by testing all subjects on a well-established submaximal mile walking test. Both groups performed a reaction time task under two levels of task complexity: simple reaction time (SRT) and complex choice reaction time (CCRT). Time to react in milliseconds was recorded for both levels of task complexity. Analysis of variance revealed that the active group reacted faster (p < .05) than the less active group on CCRT (active M, 1.100 sec; less active M, 1.818 sec). However, SRT times did not differ between groups (active M, .345 msec; less active M, .374 msec). This finding lends support to the hypothesis that cognitive task complexity influences the strength of the association between physical fitness and cognitive performance in older adults.

Restricted access

W. Jack Rejeski and Elizabeth Kenney

This study examined how exercise endurance was influenced by varying the task complexity of dissociative coping. In Trial 1, 60 subjects were randomly assigned to one of three conditions: a simple cognitive task (SCT), a complex cognitive task (CCT), or a control group (CG). All subjects were instructed to maintain an isometric contraction of 40% maximum on a handgrip dynamometer for as long as possible. Results revealed that subjects in the SCT and CCT conditions had greater endurance than those in the CG; however, varying the complexity of the task made no difference. Trial 2, a within-subjects design, was implemented to examine the potential mediating effects of task preference on cognitive coping. The protocol was identical to Trial 1 except that subjects previously assigned to the SCT condition were given the CCT and vice versa. Upon completion of Trial 2, subjects were asked which coping style they had preferred. A two-way mixed ANO-VA resulted in a significant coping style X preference interaction term. Specifically, subjects who preferred the complex task did equally well in both conditions, whereas subjects who preferred the simple task performed significantly better with the simple than with the complex task.

Restricted access

Amanda Louise Lewis and Frank F. Eves

Background/Objective:

While point-of-choice prompts consistently increase stair climbing, experimental comparisons of message content are rare. Here, the effects of 2 messages differing in complexity about the health outcomes obtainable from stair climbing were compared.

Methods:

In a UK train station with 2 independent platforms exited by identical 39-step staircases and adjacent escalators, observers recorded travelers ascent method and gender from 8:00 A.M. to 10:00 A.M. on 2 weekdays during February/March 2008 (n = 48,697). Baseline observations (2-weeks) preceded a 3-week poster phase. Two posters (594 × 841mm) that differed in the complexity of the message were positioned at the point-of-choice between ascent methods, with 1 placed on each side of the station simultaneously. Logistic regression analysis was conducted in April 2010.

Results:

Omnibus analysis contained main effects of the intervention (OR = 1.07, CI = 1.02–1.13, P = .01) and pedestrian traffic volume (OR = 5.42, CI = 3.05–9.62, P < .001). Similar effects occurred for complex (OR = 1.10, CI = 1.02–1.18, P = .01) and simple messages (OR = 1.07, CI = 1.01–1.13, P = .02) when analyses controlled for the influence of pedestrian traffic volume. There was reduced efficacy for the complex message during busier periods (OR = 0.36, CI = 0.20–0.66, P = .001), whereas the simple message was immune to these effects of traffic volume.

Conclusions:

Pedestrian traffic flow in stations can influence message effectiveness. Simple messages appear more suitable for busy sites.

Restricted access

Darren J. Paul, Paul S. Bradley and George P. Nassis

Time-motion analysis is a valuable data-collection technique used to quantify the match running performance of elite soccer players. However, interpreting the reductions in running performance in the 2nd half or temporarily after the most intense period of games is highly complex, as it could be attributed to physical or mental fatigue, pacing strategies, contextual factors, or a combination of mutually inclusive factors. Given that research in this domain typically uses a reductionist approach whereby match running performance is examined in isolation without integrating other factors, this ultimately leads to a 1-dimensional insight into match performance. Subsequently, a cohesive review of influencing factors does not yet exist. The aim of this commentary is to provide a detailed insight into the complexity of match running performance and its most influential factors.

Restricted access

Jennifer J. Heisz and Ana Kovacevic

Age-related changes in the brain can compromise cognitive function. However, in some cases, the brain is able to functionally reorganize to compensate for some of this loss. The present paper reviews the benefits of exercise on executive functions in older adults and discusses a potential mechanism through which exercise may change the way the brain processes information for better cognitive outcomes. Specifically, older adults who are more physically active demonstrate a shift toward local neural processing that is associated with better executive functions. We discuss the use of neural complexity as a sensitive measure of the neural network plasticity that is enhanced through exercise. We conclude by highlighting the future work needed to improve exercise prescriptions that help older adults maintain their cognitive and physical functions for longer into their lifespan.

Restricted access

Jay P. Mehta, Matthew D. Verber, Jon A. Wieser, Brian D. Schmit and Sheila M. Schindler-Ivens

We used functional magnetic resonance imaging (fMRI) to record human brain activity during slow (30 RPM), fast (60 RPM), passive (30 RPM), and variable rate pedaling. Ten healthy adults participated. After identifying regions of interest, the intensity and volume of brain activation in each region was calculated and compared across conditions (p < .05). Results showed that the primary sensory and motor cortices (S1, M1), supplementary motor area (SMA), and cerebellum (Cb) were active during pedaling. The intensity of activity in these areas increased with increasing pedaling rate and complexity. The Cb was the only brain region that showed significantly lower activity during passive as compared with active pedaling. We conclude that M1, S1, SMA, and Cb have a role in modifying continuous, bilateral, multijoint lower extremity movements. Much of this brain activity may be driven by sensory signals from the moving limbs.

Restricted access

Nicholas L. Holt, Danielle E. Black, Katherine A. Tamminen, Kenneth R. Fox and James L. Mandigo

We assessed young adolescent female soccer players’ perceptions of their peer group experiences. Data were collected via interviews with 34 girls from two youth soccer teams (M age = 13.0 years). Following inductive discovery analysis, data were subjected to an interpretive theoretical analysis guided by a model of peer experiences (Rubin, Bukowski, & Parker, 2006). Five categories of peer experiences were identified across three levels of social complexity. At the interaction level players integrated new members into the team and learned to interact with different types of people. At the relationship level players learned about managing peer conflict. At the group level a structure of leadership emerged and players learned to work together. Findings demonstrated interfaces between peer interactions, relationships, and group processes while also simplifying some apparently complex systems that characterized peer experiences on the teams studied.

Restricted access

Robert Sparks

Although it is apparent that conceptual reconciliation between the critical frameworks of sport and leisure studies would enable more strategic and innovative work, this paper argues that the complexity of this undertaking should not be underestimated. Several shortcomings in Deem’s analysis of theoretical integration are traced out, and a basis is struck for critically analyzing work in leisure and sports studies generally. Finally, Deem’s conception of “radical pluralism” is reviewed and a way of proceeding is proposed.

Restricted access

Phillip D. Tomporowski and Daniel M. Pendleton

examined the effects of task complexity on psychomotor learning are consistent; however, Thomas et al. ( 2017 ) found that young male adults who engaged in either circuit strength training or indoor hockey activities for 50 min following practice on a visual motor tracking task performed better than

Restricted access

Dan Weaving, Clive Beggs, Nicholas Dalton-Barron, Ben Jones and Grant Abt

important tool for practitioners when determining the likelihood of a meaningful change over time, this approach suffers from the major limitation that each individual variable generates its own individual change statistic. Therefore, given the complexity of athlete monitoring, if practitioners collect 3