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.

Performance Analysis in Ski Jumping with a Differential Global Navigation Satellite System and Video-Based Pose Estimation.

This study investigated the explanatory power of a sensor fusion of two complementary methods to explain performance and its underlying mechanisms in ski jumping. A differential Global Navigation Satellite System (dGNSS) and a markerless video-based pose estimation system (PosEst) were used to measure the kinematics and kinetics from the start of the in-run to the landing. The study had two aims; firstly, the agreement between the two methods was assessed using 16 jumps by athletes of national level from 5 m before the take-off to 20 m after, where the methods had spatial overlap. The comparison revealed a good agreement from 5 m after the take-off, within the uncertainty of the dGNSS (±0.05m). The second part of the study served as a proof of concept of the sensor fusion application, by showcasing the type of performance analysis the systems allows. Two ski jumps by the same ski jumper, with comparable external conditions, were chosen for the case study. The dGNSS was used to analyse the in-run and flight phase, while the PosEst system was used to analyse the take-off and the early flight phase. The proof-of-concept study showed that the methods are suitable to track the kinematic and kinetic characteristics that determine performance in ski jumping and their usability in both research and practice.

Alpine Ski Motion Characteristics in Slalom.

Important insight into ski function, and ultimately skier technique and tactics, can be gained by studying how measured ski trajectories compare to predictions based on theoretical models of ski-snow interaction mechanics. The aim of this investigation was to use a 3D kinematic data set collected on highly-skilled skiers during slalom race simulations to quantify ski motion characteristics and to compare these measures with theoretical predictions based primarily on ski geometrical characteristics. For slalom turns on moderate steepness (19°), ski edging angles reached maximum values of 65.7 ± 1.7° and 71.0 ± 1.9° for 10 and 13 m gate spacings. Turn radii reached minimum values of 3.96 ± 0.23 and 4.94 ± 0.59 m for the 10 and 13 m courses. These values were in good agreement with theoretical predictions by Howe (2001) of turn radius based on edging angle. Other results of the study support recent developments in understanding of the role which the ski shovel plays in groove formation during carving, and also point to the need for further study of how ski geometrical and physical characteristics interact to determine the ski's trajectory, particularly at low edge angles. These results have important implications for understanding the consequences that ski design can have for skier technique and tactics in competitive slalom skiing.

Coping with transitions in life: a four-year longitudinal narrative study of single younger people with dementia.

Background: People with younger onset dementia (YOD <65 years) experience a great transformation of existential life. Living alone, they lack the support of a partner, and have a higher risk of moving into a residential care facility. Aim: To explore how people living alone with YOD experience and cope with transitions during the progression of dementia. Method: A longitudinal qualitative approach was used. From 2014 to 2018, we interviewed 10 persons with YOD every 6 months for up to four years. Findings: Two significant main transitions and themes were registered under the perspective; experiencing and coping with (1) receiving the diagnosis of dementia and (2) moving to a residential care facility, which covers two subthemes: moving to a supported living accommodation and moving to a nursing home. To get the diagnosis was initially experienced as a dramatic disaster, while moving to residential care were mainly experienced as positive. With efficient cognitive and emotion-focused coping strategies, the participants adapted and experienced a mostly good life for a long time. Conclusion: People with dementia can describe their lived experiences for a long time after receiving the diagnosis. They adapt and preserve a feeling of a rather good life by the efficient use of various coping strategies. High-quality public support is of significant importance to assist them in sustaining quality of life and vitality.

"To be, or not to be": experiencing deterioration among people with young-onset dementia living alone.

Having dementia before the age of 65 (YOD) represents a radical break from an age-normative and expected life course. The disease afflicts the person's identity, threatens the self-image and self-confidence, and erodes the person's plans. The aim of the study was toexamine how people living alone with YOD perceive the course of dementia, their needs, and coping strategies, with a focus on narrating everyday life experiences. A longitudinal study using a qualitative approach was used. Five interviews, each with 10 informants, took place every 6 months from 2014 to 2017. The main theme is the person's experiences of changes of identity over time. The most significant aspects of their experiences of the dementia affecting them and their reactions are these: the initial signs, coping efforts, concealing the diagnosis, social retraction, existential anxiety, revival of the self, worse and worse, and health personnel as background. The study concluded thatpeople with dementia are able to describe their experiences and needs for a long time during the progression of dementia. Their voices should be listened to for planning of services. Personalized care should be used to support them in order to preserve their identity in a normalized everyday life as far as possible.

Determinants of quality of life in young onset dementia - results from a European multicenter assessment.

BACKGROUND: Promoting adaptation, improving well-being and maintaining an optimal quality of life (QOL) is an important aspect in dementia care. The purpose of this study was to identify determinants of QOL in young onset dementia, and to assess differences in QoL domains between people with Alzheimer's disease (AD) and frontotemporal dementia (FTD). METHODS: In total 135 persons with AD and 58 persons with FTD were included from two prospective cohort studies. QOL was assessed with the proxy reported quality of life in Alzheimer's disease questionnaire (QoL-AD). Possible determinants were explored using multiple linear regression and included sociodemographic variables, diagnosis, dementia severity, disease awareness, neuropsychiatric symptoms, met and unmet needs and hours of personal and instrumental care. Differences between QOL domains in people with AD and FTD were calculated using Mann-Whitney U tests. RESULTS: Lower QOL was associated with more depressive symptoms, lower disease awareness, and a higher amount of needs, both met and unmet. People with AD scored lower on the memory and higher on the friends' subscale. No differences were found for the other items. CONCLUSION: This study demonstrates a unique set of determinants of QOL in AD and FTD. Interventions directed towards these specific factors may improve QOL.

A shifting sense of being: a secondary analysis and comparison of two qualitative studies on young-onset dementia.

The aim of the present study was to investigate and interpret metaphorical expressions of the lived experiences of everyday life in people with young-onset dementia (YOD) and to compare these findings with findings from an analysis via grounded theory to see if the second analysis adds more knowledge to the topic. In this secondary analysis of data, metaphors from 20 Norwegian men and women living with YOD were investigated. Using Steger's anthropological three-step method, three categories were identified: Sliding away, leaving traces, and all alone in the world. Comprehensively, we understood the metaphors as representing the participants' shifting sense of being. The main findings of the study show that by analysing the data by combining and using both methods, more knowledge to the topic was added. Acknowledging metaphorical expressions as a source of knowledge, this study reflects on how metaphors can be used in therapeutic dialogue. We conclude that metaphors add to the understanding of descriptions of daily life in a more existential way, beyond the results gained from the grounded theory analysis. However, the findings from the analysis via grounded theory included aspects that we did not find when analysing the metaphors.

Nobody asked me how I felt: experiences of adult children of persons with young-onset dementia.

BACKGROUND: There are few studies of young persons (<65 years old) with dementia, and the situation of their children has been a neglected research field. The aim is explore how adult children of a parent with young-onset dementia have experienced the development of their parents' dementia and what needs they have for assistance. METHOD: Qualitative interviews with 14 informants (aged 20-37 years; 12 daughters, 2 sons) during 2011 were conducted and analyzed thematically. RESULTS: The informants experienced great burdens and felt neglected during the development of their parents' dementia, both by their family and by health and social services. They emphasized a need to be seen as individuals, with their experiences, feelings, and personal needs for assistance. The stresses experienced during the development of parental dementia seemed to increase conflicts in the family. There were variations in reactions between children, depending on age, gender, family structure and relationships, responsibilities, personal relations with both parents, and whether there was an adult primary caregiver. The length of time living together with the parent with dementia seemed to increase the stress and burden to the children. They expressed a great need for information and support. CONCLUSION: The findings strengthen the notion of the need for family-oriented support, combined with person-centered care for the children according to their needs. In addition, group meetings and contact with other young people in the same stage of life could be of interest for some.

Assessment of dementia by a primary health care dementia team cooperating with the family doctor - the Norwegian model.

BACKGROUND: To describe how dementia assessment could be organized in primary health care and how it works. METHODS: The project had two phases. In phase one 104 elderly patients were assessed by a local authority dementia team that used a standardized examination protocol, which enabled the family doctors to establish a dementia diagnosis. After evaluation and adjustments the model was extended to 31 local authorities and 474 patients were assessed. RESULTS: The mean age of the patients was 84.4 (SD 5.6) and 81.8 (SD 7.8) years, respectively; 81 and 67% were women, respectively. The mean Mini Mental State Examination scores were 21.1 (SD 5.0) and 19.2 (SD 5.1), respectively. All patients in phase one and 70% in phase two were diagnosed with dementia. In 15 local authorities a specially assigned family doctor assisted in establishing diagnoses. In these local authorities 80% of the patients were diagnosed. CONCLUSION: A local authority dementia team can collect the information required to enable a family doctor to establish a dementia diagnosis. Ideally, such teams should be assisted by a family doctor interested in dementia diagnostics.

[Early onset dementia]. / Når demens rammer unge.

BACKGROUND: It is estimated that 1,200 people under the age of 65 have been diagnosed with dementia in Norway. This article provides an overview of the types of dementia frequently seen in younger patients. MATERIAL AND METHODS: The article is based on a non-systematic search in PubMed, as well as the authors' own clinical and research experience. RESULTS: Alzheimer's disease, frontotemporal dementia, vascular dementia and dementia with Lewy bodies, are the most common types of dementia occurring more often in younger than in older patients. The cognitive symptoms are more variable in younger patients than in older. Only a small percentage of early onset dementia is caused by genetic factors. There are few diagnostic tools available for this age group and it takes considerable time to reach a correct diagnosis. Early diagnosis allows the patient and carer to plan for the future. INTERPRETATION: Physicians should be aware that dementia can occur in younger people, and more diagnostic assessments should be developed for this patient group. Better coordination from the public health authority and municipalities is needed to provide respite care for early onset dementia patients and their carers.

Support to family carers of patients with frontotemporal dementia.

OBJECTIVES: To examine the provision of support to patients with frontotemporal dementia (FTD) and their family carers compared with patients with early onset Alzheimer's dementia (AD) and their carers, and the carers' satisfaction with the support. METHOD: Data came from 60 dyads of patients with dementia and their principal family carers, 23 subjects with frontotemporal dementia and their 23 carers, and 37 subjects with early onset Alzheimer's disease and their 37 carers. RESULTS: Patients with a frontotemporal dementia diagnosis were significantly more frequently offered stays in nursing homes (p = 0.04). Carers of patients with frontotemporal dementia were significantly less satisfied with the provision of information about the disease compared with carers of early onset Alzheimer's disease patients (p = 0.05) and were significantly less satisfied with counseling and follow-up advice (p = 0.05). CONCLUSION: Changes of personality in patients with frontotemporal dementia may be the major reason why they were offered more stays in institutions. These family carers tend to be less satisfied with the provision of support they received from the specialist health service compared to carers of Alzheimer's disease patients, and are in need of more, and other forms of support.

Validation of the Seven Minute Screen and Syndrom Kurztest among elderly Norwegian outpatients.

BACKGROUND: Brief cognitive tests represent a first step in the assessment of elderly people referred to outpatient clinics because of cognitive impairment. The aim of this study is to determine sensitivity, specificity and likelihood ratio for a positive result (LR+) for the brief cognitive tests Seven Minute Screen (7MS) and Syndrom Kurztest (SKT) in an outpatient sample of elderly patients with no dementia or mild dementia. METHODS: Ninety-five patients aged 65 years or more from 10 Norwegian geriatric and psychogeriatric outpatient clinics were included in the study. All the subjects had a Mini-mental State Examination score of 22-30. A consensus diagnosis of dementia according to ICD-10 was established by an expert panel that considered data from a standardized assessment protocol blinded for 7MS and SKT results. RESULTS: Subjects were diagnosed with mild dementia (n = 69) or no dementia (n = 26). Sensitivity for 7MS was 71%, specificity 73% and LR+ was 2.6. Sensitivity for SKT was 65%, specificity 65% and LR+ was 1.9. CONCLUSION: Sensitivity, specificity and LR+ for 7MS and SKT were unacceptably low in this outpatient sample.

Frontotemporal dementia: a clinically complex diagnosis.

OBJECTIVE: To compare the time taken to establish a clinical diagnosis of Frontotemporal dementia (FTD) relative to a diagnosis of early onset Alzheimer's dementia (AD). METHODS: The data came from 89 patients under the age of 65 years, 52 of whom met the Manchester-Lund criteria for Frontotemporal dementia; 20 of these came from Lund University Hospital in Sweden. The other 32 patients with FTD along with 37 subjects who fulfilled the ICD-10 criteria for early onset Alzheimer's disease were recruited from four memory clinics and two neurology departments in Norway. RESULTS: For FTD patients in Norway it took 59.2 months (SD 36.1) from the onset of illness until a clinical FTD diagnosis was made. The corresponding time period for FTD patients in Sweden is 49.5 months (SD 24.5) and for AD patients in Norway 39.1 months (SD 19.9). The time from the first visit to a medical doctor until a diagnosis was made for the FTD patients in Norway was 34.5 months (SD 22.6), for the Swedish FTD patients 23.1 months (SD 22.4) and for the AD patients 25.9 months (SD 13.1). In all, 71% of FTD patients and 30% of AD patients initially received a non-dementia diagnosis. CONCLUSION: More knowledge about early presenting cognitive and behavioural signs of FTD is needed in both primary and secondary health care to reduce the time period needed to establish a clinical diagnosis of FTD.

Knee angular displacement and extensor muscle activity in telemark skiing and in ski-specific strength exercises.

Much of the training of competitive telemark skiers is performed as dry-land exercises. The specificity of these exercises is important for optimizing the training effect. Our aim here was to study the activation of the knee extensor musculature and knee angular displacement during competitive telemark skiing and during dry-land strength training exercises to determine the specificity of the latter. Specificity was analysed with respect to angular amplitude, angular velocity, muscle action and electromyographic (EMG) activity. Five male telemark skiers of national and international standard volunteered to participate in the study, which consisted of two parts: (1) skiing a telemark ski course and (2) specific dry-land strength training exercises for telemark skiing (telemark jumps and barbell squats). The angular displacement of the right knee joint was recorded with an electrogoniometer. A tape pressure sensor was used to measure pressure between the sole of the foot and the bottom of the right ski boot. Electromyographic activity in the right vastus lateralis was recorded with surface electrodes. The EMG activity recorded during maximum countermovement jumps was used to normalize the EMG activity during telemark skiing, telemark jumps and barbell squats. The results showed that knee angular displacement during telemark skiing and dry-land telemark jumps had four distinct phases: a flexion (F1) and extension (E1) phase during the thrust phase of the outside ski/leg in the turn/jump and a flexion (F2) and extension (E2) phase when the leg was on the inside of the turn/jump. The vastus lateralis muscle was activated during F1 and E1 in the thrust phase during telemark skiing and telemark jumps. The overall net knee angular amplitude was significantly greater (P < 0.05) for telemark jumps than for telemark skiing. Barbell squats showed a knee angular amplitude significantly greater than that in telemark skiing (P < 0.05). The mean knee angular velocity of the F1 and E1 phases during telemark skiing was about 0.47 rad x s(-1); during barbell squats, it was about 1.22 rad x s(-1). The angular velocity during telemark jumps was 2.34 and 1.59 rad x s(-1) in the F1 and E1 phase, respectively. The normalized activation level of the EMG bursts during telemark skiing, telemark jumps and barbell squats was 70-80%. In conclusion, the muscle action and level of activation in the vastus lateralis during the F1 and E1 phases were similar during telemark skiing and dry-land exercises. However, the dry-land exercises showed a larger knee extension and flexion amplitude and angular velocity compared with telemark skiing. It appears that an adjustment of knee angular velocity during barbell squats and an adjustment of knee angle amplitude during both telemark jumps and barbell squats will improve specificity during training.