| 1. |
- Markström, Jonas, et al.
(författare)
-
Countermovement jump peak force relative to body weight and jump height as predictors for sprint running performances : (in)homogeneity of track and field athletes?
- 2013
-
Ingår i: Journal of Strength and Conditioning Research. - Philadelphia : Lippincott Williams & Wilkins. - 1064-8011 .- 1533-4287. ; 27:4, s. 944-953
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to investigate: (1) If variables from one-leg drop jump (DJ), DJ, squat jump (SJ), and counter movement jump (CMJ) tests can predict sprint performances for sprinters. (2) If sprinters and jumpers can be distinguished based on variables from one-leg DJ, DJ, SJ, and CMJ tests, also if sprinters and throwers can be distinguished based on variables from stiff leg jump (SLJ), SJ, and CMJ tests. A single linear regression and multiple linear regression analysis approach with models including two or three variables were used when predicting sprint performances. Five elite sprinters (1 female) participated in the first subexamination and five sprinters (1 female) vs five jumpers and six sprinters vs. six throwers (4 females) participated in the second. The force variable CMJ peak force relative to body weight significantly predicted the sprint performances maximal running velocity through 10 m (Vmax10m) and 60 m time. Vmax10m was also predicted by CMJ height. Jump heights from SJ and DJ did not predict sprint performances. The between group analysis of the athletes showed a non-significant group difference with respect to the jump variables. However, planned comparisons between sprinters and throwers showed significant differences on a number of SLJ variables. When constructing training programs for sprinters, aim should be to improve CMJ peak force and CMJ height because of the prediction of Vmax10m and 60 m time, presumably due to velocity specificity components.
|
|
| 2. |
- Molander, Bo, et al.
(författare)
-
Regulating force in putting by using the Borg CR100 scale®
- 2013
-
Ingår i: Frontiers in Psychology. - : Frontiers Media SA. - 1664-1078. ; 4
-
Tidskriftsartikel (refereegranskat)abstract
- Studies investigating the regulation of force of motor actions are scarce, and particularly so in the area of sports. This is surprising, considering that in most sports precise force is of great importance. The current study demonstrates how a psychophysical scale, the Borg CR100 scale® (Borg and Borg, 2001), can be used to assess subjective force as well as regulate force in putting. Psychophysical functions were calculated on the relationships between judgments of force using the CR100 scale and the length of putting shots, examined in a laboratory setting, where 44 amateur golfers played on both flat and uphill surfaces. High agreement and consistency between CR 100 ratings and distances putted was demonstrated. No significant differences in handling the scale were observed between younger (mean age ≈37 years) and older (mean age ≈69 years) players or between players of different skill level. This study provides a new innovative use of an existing instrument, the Borg CR 100 scale®, in order to understand the regulation of force needed for putts of various lengths and surfaces. These results and the potential future benefits of the psychophysical approach in golf are discussed.
|
|
| 3. |
- Månsson, Kristoffer N T, et al.
(författare)
-
Altered neural correlates of affective processing after internet-delivered cognitive behavior therapy for social anxiety disorder
- 2013
-
Ingår i: Psychiatry Research. - : Elsevier BV. - 0925-4927 .- 1872-7506 .- 0165-1781 .- 1872-7123. ; 214:3, s. 229-237
-
Tidskriftsartikel (refereegranskat)abstract
- Randomized controlled trials have yielded promising results for internet-delivered cognitive behavior therapy (iCBT) for patients with social anxiety disorder (SAD). The present study investigated anxiety-related neural changes after iCBT for SAD. The amygdala is a critical hub in the neural fear network, receptive to change using emotion regulation strategies and a putative target for iCBT. Twenty-two subjects were included in pre- and post-treatment functional magnetic resonance imaging at 3T assessing neural changes during an affective face processing task. Treatment outcome was assessed using social anxiety self-reports and the Clinical Global Impression-Improvement (CGI-I) scale. ICBT yielded better outcome than ABM (66% vs. 25% CGI-I responders). A significant differential activation of the left amygdala was found with relatively decreased reactivity after iCBT. Changes in the amygdala were related to a behavioral measure of social anxiety. Functional connectivity analysis in the iCBT group showed that the amygdala attenuation was associated with increased activity in the medial orbitofrontal cortex and decreased activity in the right ventrolateral and dorsolateral (dlPFC) cortices. Treatment-induced neural changes with iCBT were consistent with previously reported studies on regular CBT and emotion regulation in general.
|
|
| 4. |
- Månsson, Kristoffer N.T., et al.
(författare)
-
Multi-voxel Patterns in Fear Network Regions Predict Clinical Outcome One-year after Cognitive Behavior Therapy for Social Anxiety Disorder : A Support Vector Machine fMRI Study
- 2014
-
Ingår i: Biological Psychiatry. - : Elsevier. ; , s. 83S-84S
-
Konferensbidrag (refereegranskat)abstract
- Background: Cognitive behavioral therapy (CBT) has yielded robust treatment effects for social anxiety disorder (SAD) but still many patients do not respond fully to treatment, and a substantial proportion relapse after treatment has ended. Identification of robust predictors of sustained treatment responses could be of high clinical importance. Methods: We used functional magnetic resonance imaging (fMRI; 3T General Electric) to assess 26 patients (85% women, mean age 32.3 years) with SAD. Blood-oxygen-level dependent (BOLD) responses to self-referential criticism, i.e. reading sentences such as “Nobody likes you” were compared to criticism referring to other individuals. Responses in the fear network, i.e. the amygdala, hippocampus, anterior cingulate cortex (ACC), and insula, were evaluated in a Support Vector Machine (SVM) approach to predict treatment outcome one-year after Internet-delivered CBT. We applied leave-one-out cross-validation to increase the generalizability of the data. Results: At one-year follow-up, three patients had dropped out. Twelve (52%) of the assessed patients met the response criteria, i.e. very much or much improved according to the Clinical Global Impression-Improvement scale (CGI-I). SVM on initial BOLD response, accurately classified patients according to responder status, based on multi-voxel patterns in the ACC (balanced accuracy of 91.7%, p=.001, Figure 1), and the ACC together with the amygdala (83.0%, p=.004) as well as the hippocampus (73.9%, p=.032). Conclusions: We demonstrate that initial multi-voxel BOLD response patterns to self-referential criticism in the ACC, amygdala, and hippocampus are highly predictive of long-term improvement of CBT in patients with SAD.
|
|
| 5. |
|
|
| 6. |
- Olsson, Carl-Johan, 1980-, et al.
(författare)
-
Increased prefrontal activity and reduced motor cortex activity during imagined eccentric compared to concentric muscle actions
- 2012
-
Ingår i: Frontiers in Human Neuroscience. - : Frontiers Media SA. - 1662-5161. ; 6:255
-
Tidskriftsartikel (refereegranskat)abstract
- In this study we used functional magnetic resonance imaging (fMRI) to examine differences in recruited brain regions during the concentric and the eccentric phase of an imagined maximum resistance training task of the elbow flexors in healthy young subjects. The results showed that during the eccentric phase, pre-frontal cortex (BA44) bilaterally was recruited when contrasted to the concentric phase. During the concentric phase, however, the motor and pre-motor cortex (BA 4/6) was recruited when contrasted to the eccentric phase. Interestingly, the brain activity of this region was reduced, when compared to the mean activity of the session, during the eccentric phase. Thus, the neural mechanisms governing imagined concentric and eccentric contractions appear to differ. We propose that the recruitment of the pre-frontal cortex is due to an increased demand of regulating force during the eccentric phase. Moreover, it is possible that the inability to fully activate a muscle during eccentric contractions may partly be explained by a reduction of activity in the motor and pre-motor cortex.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Olsson, Carl-Johan, 1980-, et al.
(författare)
-
Using action observation to study superior motor performance : a pilot fMRI study
- 2013
-
Ingår i: Frontiers in Human Neuroscience. - : Frontiers Research Foundation. - 1662-5161. ; 7
-
Tidskriftsartikel (refereegranskat)abstract
- The most efficient way to acquire motor skills may be through physical practice. Nevertheless, it has also been shown that action observation may improve motor performance. The aim of the present pilot study was to examine a potential action observation paradigm used to (1) capture the superior performance of expert athletes and (2) capture the underlying neural mechanisms of successful action observation in relation to task experience. We used functional magnetic resonance imaging to measure regional blood flow while presenting videos of a hockey player shooting a puck toward a hockey goal. The videos (a total of 120) where stopped at different time frames with different amount of information provided, creating a paradigm with three different levels of difficulty to decide the fate of a shot. Since this was only a pilot study, we first tested the paradigm behaviorally on six elite expert hockey players, five intermediate players, and six non-hockey playing controls. The results showed that expert hockey players were significantly (p < 0.05) more accurate on deciding the fate of the action compared to the others. Thus, it appears as if the paradigm can capture superior performance of expert athletes (aim 1). We then tested three of the hockey players and three of the controls on the same paradigm in the MRI scanner to investigate the underlying neural mechanisms of successful action anticipation. The imaging results showed that when expert hockey players observed and correctly anticipated situations, they recruited motor and temporal regions of the brain. Novices, on the other hand, relied on visual regions during observation and prefrontal regions during action decision. Thus, the results from the imaging data suggest that different networks of the brain are recruited depending on task experience (aim 2). In conclusion, depending on the level of motor skill of the observer, when correctly anticipating actions different neural systems will be recruited.
|
|
