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Stephan Swinnen, Joost Vandenberghe and Erik Van Assche

This study sought to determine the relationships between the cognitive styles field dependence-independence and reflection-impulsivity and the acquisition of a gross motor skill in an unstructured learning environment. In reference to the first cognitive style construct, it was hypothesized that field-independent subjects perform better than field-dependent subjects because they provide organization when the material to be learned lacks structure, leading them to rely on their analyzing and restructuring ability. The second construct refers to cognitive inhibition required for response uncertainty tasks as well as motor impulse inhibition. Subjects (57 boys, 65 girls) were 13-year-old junior high school students. Several visual perceptual tests were administered and gymnastic performance scores were measured at pretest, during the learning session, and posttest. The hypothesis that field-independent subjects are more successful in an unstructured learning environment than field-dependent subjects was confirmed for boys only. The correlations between the reflection-impulsivity variables and gymnastic performance were generally low, and no support could be found for the hypothesis that reflective subjects are more successful in learning the skill than impulsive subjects.

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Gary R. Gray

This study was conducted to determine the reasons that influence the decision to settle a personal injury lawsuit rather than proceed to court for a trial. Additionally, this study compared plaintiff attorneys’ and insurance company attorneys’ reasons for settlement in personal injury lawsuits to determine whether there are significant differences between the two groups. Subjects, 28 plaintiff attorneys and 57 insurance company attorneys, rated the importance of or degree of agreement with 77 statements related to their decision to settle or to recommend settlement. T tests revealed significant differences between the two groups on 31 of the 77 items. Among all 85 attorneys, the top four reasons for settlement were (a) if the opposing attorney offers realistic settlement figures, a jury trial will offer more risk than advantage; (b) settlements are an attractive alternative to a trial partly because of the high costs of litigation; (c) in deciding whether to settle, attorneys attempt to determine the probable verdict in light of the evidence; and (d) attorneys attempt to determine the value of an immediate settlement compared to the uncertainty of a trial.

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Xavier Ohl, Pierre-Yves Lagacé, Fabien Billuart, Olivier Gagey, Wafa Skalli and Nicola Hagemeister

A robust and reproducible scapular coordinate system is necessary to study scapulothoracic kinematics. The coordinate system recommended by the ISB (International Society of Biomechanics) is difficult to apply in studies using medical imaging, which mostly use a glenoid-centered coordinate system. The aim of this study was to assess the robustness of a glenoid-centered coordinate system compared with the ISB coordinate system, and to study the reproducibility of this coordinate system measure during abduction. A Monte-Carlo analysis was performed to test the robustness of the two coordinate systems. This method enabled the variability of the orientation of the coordinate system to be assessed in a laboratory setting. A reproducibility study of the glenoid-centered coordinate system in the thorax reference frame was performed during abduction in the scapular plane using a low-dose stereoradiography system. We showed that the glenoid-centered coordinate system was slightly more robust than the ISB-recommended coordinate system. Most reproducible rotation was upward/downward rotation (x axis) and most reproducible translation was along the Y axis (superior-inferior translation). In conclusion, the glenoid-centered coordinate system can be used with confidence for scapular kinematics analysis. The uncertainty of the measures derived from our technique is acceptable compared with that reported in the literature. Functional quantitative analysis of the scapulothoracic joint is possible with this method.

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Cyril Schmit, Rob Duffield, Christophe Hausswirth, Aaron J. Coutts and Yann Le Meur

Purpose:

To describe the effect of the initial perceptual experience from heat familiarization on the pacing profile during a freepaced endurance time trial (TT) compared with temperate conditions.

Methods:

Two groups of well-trained triathletes performed two 20-km TTs in either hot (35°C and 50% relative humidity [RH], n = 12) or temperate (21°C and 50% RH, n = 22) conditions, after standardization of training for each group before both trials. To ensure no physiological acclimation differences between conditions, the TTs for both groups were separated by 11 ± 4 d.

Results:

Performance improvement in the heat (11 ± 24 W) from the 1st to 2nd trial appeared comparable to that in temperate conditions (8 ± 14 W, P = .67). However, the specific alteration in pacing profile in the heat was markedly different than temperate conditions, with a change from “positive” to an “even” pacing strategy.

Conclusions:

Altered perceptions of heat during heat familiarization, rather than physiological acclimatization per se, may mediate initial changes in pacing and TT performance in the heat. These results highlight the need for athletes without time for sufficient heat acclimatization to familiarize themselves with hot conditions to reduce the uncertainty from behavior-based outcomes that may impede performance.

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Marj Moodie, Michelle M. Haby, Boyd Swinburn and Robert Carter

Background:

To assess from a societal perspective the cost-effectiveness of a school program to increase active transport in 10- to 11-year-old Australian children as an obesity prevention measure.

Methods:

The TravelSMART Schools Curriculum program was modeled nationally for 2001 in terms of its impact on Body Mass Index (BMI) and Disability-Adjusted Life Years (DALYs) measured against current practice. Cost offsets and DALY benefits were modeled until the eligible cohort reached age 100 or died. The intervention was qualitatively assessed against second stage filter criteria (‘equity,’ ‘strength of evidence,’ ‘acceptability to stakeholders,’ ‘feasibility of implementation,’ ‘sustainability,’ and ‘side-effects’) given their potential impact on funding decisions.

Results:

The modeled intervention reached 267,700 children and cost $AUD13.3M (95% uncertainty interval [UI] $6.9M; $22.8M) per year. It resulted in an incremental saving of 890 (95%UI −540; 2,900) BMI units, which translated to 95 (95% UI −40; 230) DALYs and a net cost per DALY saved of $AUD117,000 (95% UI dominated; $1.06M).

Conclusions:

The intervention was not cost-effective as an obesity prevention measure under base-run modeling assumptions. The attribution of some costs to nonobesity objectives would be justified given the program’s multiple benefits. Cost-effectiveness would be further improved by considering the wider school community impacts.

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Faye Prior, Margaret Coffey, Anna Robins and Penny Cook

Background: Exercise referral schemes (ERSs) support inactive adults, who have chronic health conditions, to become physically active. Uncertainty exists regarding the effectiveness of ERSs, with few studies evaluating their long-term impact. The aims of this study were to evaluate the long-term impact (12 mo) of participation in an ERS on self-reported physical activity (PA) and a range of health-related outcomes. Methods: Data were analyzed for participants of a 24-week ERS who attended a week 52 follow-up between July 2015 and 2017. PA and health-related outcomes collected at weeks 1, 24, and 52 were analyzed using the Friedman test and Wilcoxon signed-ranks test. Results: A total of 273 participants attended the week 52 follow-up. Self-reported PA significantly increased by a median of 636 MET minutes at week 52. There were also significant improvements in body mass index, systolic blood pressure, mental well-being, and health-related quality of life. Conclusions: For every 8 participants referred to this 24-week ERS, 1 participant went on to show long-term improvements in at least 1 health indicator. The evidence base requires further long-term evaluations to confirm these findings across a range of ERS providers. Changes in self-reported PA would be supported by the inclusion of device-based measurment of PA.

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Roy J. Shephard

The Journal of Physical Activity and Health seems likely to develop as a vehicle for practical, evidence-based answers to problems concerning physical activity and health, issues that have important implications for public health policy. There is strong epidemiological evidence for an association between the regular practice of physical activity and preventive or therapeutic benefit in a wide range of chronic health conditions,1-4 and already many professional groups have been eager to pre¬pare position statements, indicating their assessments of an appropriate minimum weekly dose of physical activity to maintain health.5 Unfortunately, there have been substantial discrepancies between successive recommendations, and uncertainties in the message are one probable factor, limiting its acceptance by both the general public and immediate health-care providers.6,7 The purpose of this brief commentary is to suggest some areas of investigation that would help in formulating a clear and consistent message. Topics discussed include the desired health outcome, the shape of the dose–response relationship, the impact of confounding variables, the quality of the evidence accepted, the basis for shaping the message, and the need for multiple messages.

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Thomas Gotschi

Background:

Promoting bicycling has great potential to increase overall physical activity; however, significant uncertainty exists with regard to the amount and effectiveness of investment needed for infrastructure. The objective of this study is to assess how costs of Portland’s past and planned investments in bicycling relate to health and other benefits.

Methods:

Costs of investment plans are compared with 2 types of monetized health benefits, health care cost savings and value of statistical life savings. Levels of bicycling are estimated using past trends, future mode share goals, and a traffic demand model.

Results:

By 2040, investments in the range of $138 to $605 million will result in health care cost savings of $388 to $594 million, fuel savings of $143 to $218 million, and savings in value of statistical lives of $7 to $12 billion. The benefit-cost ratios for health care and fuel savings are between 3.8 and 1.2 to 1, and an order of magnitude larger when value of statistical lives is used.

Conclusions:

This first of its kind cost-benefit analysis of investments in bicycling in a US city shows that such efforts are cost-effective, even when only a limited selection of benefits is considered.

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Michael Joch, Mathias Hegele, Heiko Maurer, Hermann Müller and Lisa K. Maurer

Motor learning can be monitored by observing the development of neural correlates of error processing. Among these neural correlates, the error- and feedback-related negativity (Ne/ERN and FRN) represent error processing mechanisms. While the Ne/ERN is more related to error prediction, the FRN is found after an error is manifested. The questions the current study strives to answer are: What information is needed by the system to make error predictions and how is this represented by the Ne/ERN and FRN in a complex motor task? We reduced the information and increased the difficulty level for the prediction in a semivirtual throwing task and found no Ne/ERN but a large FRN when the action result was finally observed (hitting or missing a target). We assume that uncertainty for error prediction was too high (either due to insufficient information or due to lacking prerequisites for prediction), such that error processing had to be mainly based on feedback. The finding is in line with the reinforcement theory of learning, after which Ne/ERN and FRN should behave complementary.

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Paul G. Montgomery and Will G. Hopkins

Australian Football is an intense team sport played over ~120 min on a weekly basis. To determine the effects of game and training load on muscle soreness and the time frame of soreness dissipation, 64 elite Australian Football players (age 23.8 ± 1.8 y, height 183.9 ± 3.8 cm, weight 83.2 ± 5.0 kg; mean ± SD) recorded perceptions of muscle soreness, game intensity, and training intensity on scales of 1–10 on most mornings for up to 3 competition seasons. Playing and training times were also recorded in minutes. Data were analyzed with a mixed linear model, and magnitudes of effects on soreness were evaluated by standardization. All effects had acceptably low uncertainty. Game and training-session loads were 790 ± 182 and 229 ± 98 intensity-minutes (mean ± SD), respectively. General muscle soreness was 4.6 ± 1.1 units on d 1 postgame and fell to 1.9 ± 1.0 by d 6. There was a small increase in general muscle soreness (0.22 ± 0.07–0.50 ± 0.13 units) in the 3 d after high-load games relative to low-load games. Other soreness responses showed similar timelines and magnitudes of change. Training sessions made only small contributions to soreness over the 3 d after each session. Practitioners should be aware of these responses when planning weekly training and recovery programs, as it appears that game-related soreness dissipates after 3 d regardless of game load and increased training loads in the following week produce only small increases in soreness.