| 1. |
- Almqvist, Andreas, et al.
(författare)
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A Scientific Perspective on Reducing Ski-Snow Friction to Improve Performance in Olympic Cross-Country Skiing, the Biathlon and Nordic Combined
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media S.A.. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Of the medals awarded at the 2022 Winter Olympics in Beijing, 24% were for events involving cross-country skiing, the biathlon and Nordic combined. Although much research has focused on physiological and biomechanical characteristics that determine success in these sports, considerably less is yet known about the resistive forces. Here, we specifically describe what is presently known about ski-snow friction, one of the major resistive forces. Today, elite ski races take place on natural and/or machine-made snow. Prior to each race, several pairs of skis with different grinding and waxing of the base are tested against one another with respect to key parameters, such as how rapidly and for how long the ski glides, which is dependent on ski-snow friction. This friction arises from a combination of factors, including compaction, plowing, adhesion, viscous drag, and water bridging, as well as contaminants and dirt on the surface of and within the snow. In this context the stiffness of the ski, shape of its camber, and material composition and topography of the base exert a major influence. An understanding of the interactions between these factors, in combination with information concerning the temperature and humidity of both the air and snow, as well as the nature of the snow, provides a basis for designing specific strategies to minimize ski-snow friction. In conclusion, although performance on “narrow skis” has improved considerably in recent decades, future insights into how best to reduce ski-snow friction offer great promise for even further advances.
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| 2. |
- Bentzen, Marte, et al.
(författare)
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Monitoring mental distress in Para athletes in preparation, during and after the Beijing Paralympic Games 2022 : A 22 week prospective mixed-method study.
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media S.A.. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- It is common in elite sport to monitor athletes' training load, injuries and illnesses, but mental distress is rarely included. An improved understanding of the epidemiology of mental distress among elite Para athletes and how their coaches perceive such monitoring would allow us to better develop and implement preventive measures. The purpose of this study was therefore to (1) prospectively describe elite Para athletes' mental distress, before, during and after the Beijing Paralympic Games (Paralympics Games 22 = PG22); and to (2) gain a better understanding of if and potentially how awareness of athletes' mental distress changed, through weekly monitoring, and influenced how coachers perceive athletes' mental distress and if they accounted for this before, during and after PG22. A mixed-method study design was used, in which prospective mental distress (depression and anxiety) data were collected weekly from 13 [Swedish] elite Para athletes in preparation, during and after PG22. Data were screened and evaluated weekly by a physiotherapist and a sports psychologist, and coaches also received weekly reports. A focus-group interview with the coaches were conducted post Paralympics to address coaches' awareness about mental distress and athlete health monitoring in Parasport. For data analyses, descriptive statistics was used for the quantitative data and a content analysis was conducted for the qualitative data. The results reveled the following proportion of datapoints indicating symptoms of anxiety and depression: before PG22 (15.8 and 19.1%); during PG22 (47.6 and 38.2%); and after PG22 (0 and 11.8%). The qualitative results indicated that coaches perceived athlete health monitoring as helpful for increasing their awareness of mental distress, and as a useful tool to initiate support for their athletes as well as improving their coaching. In summary, this cohort of elite Para athletes reported a high proportion of mental distress during the Winter Paralympic Games in Beijing. The results also show that it is important and feasible to monitor Para athletes' mental distress to detect and manage early symptoms of mental distress.
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| 3. |
- Bjørke, Ann Christin Helgesen, et al.
(författare)
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Exploring Moderators of the Effect of High vs. Low-to-Moderate Intensity Exercise on Cardiorespiratory Fitness During Breast Cancer Treatment - Analyses of a Subsample From the Phys-Can RCT
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media S.A.. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: The results from the physical training and cancer randomized controlled trial (Phys-Can RCT) indicate that high intensity (HI) strength and endurance training during (neo-)adjuvant cancer treatment is more beneficial for cardiorespiratory fitness (CRF, measured as peak oxygen uptake [VO2peak]) than low-to-moderate intensity (LMI) exercise. Adherence to the exercise intervention and demographic or clinical characteristics of patients with breast cancer undergoing adjuvant treatment may moderate the exercise intervention effect on VO2peak. In this study, the objective was to investigate whether baseline values of VO2peak, body mass index (BMI), time spent in moderate- to vigorous-intensity physical activity (MVPA), physical fatigue, age, chemotherapy treatment, and the adherence to the endurance training moderated the effect of HI vs. LMI exercise on VO2peak.Materials and Methods: We used data collected from a subsample from the Phys-Can RCT; women who were diagnosed with breast cancer and had a valid baseline and post-intervention VO2peak test were included (n = 255). The exercise interventions from the RCT included strength and endurance training at either LMI, which was continuous endurance training at 40–50% of heart rate reserve (HRR), or at HI, which was interval training at 80–90% of HRR, with similar exercise volume in the two groups. Linear regression analyses were used to investigate moderating effects using a significance level of p < 0.10. Statistically significant interactions were examined further using the Johnson–Neyman (J-N) technique and regions of significance (for continuous variables) or box plots with adjusted means of post-intervention VO2peak (for binary variables).Results: Age, as a continuous variable, and adherence, dichotomized into < or > 58% based on median, moderated the effect of HI vs. LMI on CRF (B = −0.08, 95% CI [−0.16, 0.01], pinteraction = 0.06, and B = 1.63, 95% CI [−0.12, 3.38], pinteraction = 0.07, respectively). The J-N technique and regions of significance indicated that the intervention effect (HI vs. LMI) was positive and statistically significant in participants aged 61 years or older. Baseline measurement of CRF, MVPA, BMI, physical fatigue, and chemotherapy treatment did not significantly moderate the intervention effect on CRF.Conclusion: Women with breast cancer who are older and who have higher adherence to the exercise regimen may have larger effects of HI exercise during (neo-)adjuvant cancer treatment on CRF.
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| 4. |
- Björklund, Glenn, 1972-, et al.
(författare)
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How Does the Starting Order in the First and Second Run Affect the Final Rank in the FIS World Cup Giant Slalom?
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media S.A.. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to determine the impact of runs 1 and 2 on overall rank in Giant Slalom. Data from 15 seasons (2005/2006–2019/2020) including and unique starts for women (n = 2,294) and men (n = 2,328) were analyzed. Skiers were grouped based on final ranks 1–3 (G3), 4–10 (G10), and 11–20 (G20) and separately analyzed for women and men. A Wilcoxon-signed rank test was used for comparisons between runs 1 and 2, while a multi-nominal logistic regression was used to identify odds ratios (OR) associated with group rank. Women had similar run times for runs 1 and 2 (p = 0.734), while men had faster times on run 2 (p < 0.001). The strongest association to G3 was during run 1 for run time (men: OR 1.06–1.12; women: OR 1.06–1.11, all p < 0.01) and gate-to-gate times (men: OR 33–475; women: OR 81–2,301, all p < 0.001). Overall, this study demonstrates the importance of a fast first run for improving the final ranking group and the need to increase the tempo going from the first to the second run for men. Copyright © 2022 Björklund and Swarén.
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| 5. |
- Björklund, Glenn, 1972-, et al.
(författare)
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The Determinants of Performance in Biathlon World Cup Sprint and Individual Competitions
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media SA. - 2624-9367. ; 4:March, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: The present study aimed to determine the association of skiing speed (SS), range time (RT), and the number of missed targets (MT) with rank in sprint and individual biathlon competitions.Methods: Data were collected from the International Biathlon Union's database for 17 seasons (2002/2003–2018/2019). Furthermore, the biathletes were divided into three rank groups (G3, rank 1–3; G10, rank 4–10; and G20, rank 11–20). Multinominal regression was used to detect odds ratios associated with group rank for both sexes, separately.Results: MT was the only variable that was constantly related to G3 (OR 1.90–6.35, all p < 0.001) for both women and men. SS was associated with G3 in the last lap in the sprint for both sexes (OR 0.46–0.66, all p < 0.001) and RT for standing shooting (OR 1.04–1.14, all p < 0.05).Conclusion: These results show that shooting is the fundamental factor for performance in both competitions, but that SS is increasingly important for the last lap in the sprint for both sexes. Further, a fast RT in the standing shooting for women in individual and men in the sprint seems important for improving final rank.
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| 6. |
- Broms, Lovisa, 1987-, et al.
(författare)
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Accessibility, Agency, and Trust: A Study About Equestrians' (Online) Learning Repertoires
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media S.A.. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Todays' online media landscape facilitates communication on how sports practitioners can develop in their sport. Hence, sports and educational institutions need to recognize the increased role of the individual as “a facilitator of knowledge” through information and communications technology (ICT). For sport organizations and educational institutions to effectively reach out with knowledge and research, they need to know how individuals assess, value, and trust information sources. This article aims to increase the knowledge and understanding of how the traditional culture in equestrianism meets the contemporary media user. It is based on a study that uses a mixed methods design, containing a questionnaire with 1,655 respondents and 28 focus group interviews with Swedish and Norwegian equestrians, to investigate how equestrians create their own repertoires of horse-knowledge online and what sources of knowledge they trust and prioritize. The results show that accessibility, agency, and trust are key terms when mapping equestrians' preferred knowledge platforms, and that equestrians are generally not satisfied with the availability and the quality of horse-related online content. Horse experience is the most important positional factor influencing online repertoires in the equestrian community. Riders with less experience turn to Social Network Sites (SNS) to a higher extent than riders with more experience. Further, equestrians find the ability to assess information as an important yet challenging task. This article shows that the term (online) learning repertoires is appropriate when discussing the relationship (or clash) between the traditional culture in equestrian sports and the contemporary media user. On the one hand, many equestrians clearly express that they would rather stay away from obtaining information about horses and riding on ICTs. On the other hand, the data, together with previous research, indicates that many equestrians see ICTs as important platforms for discussing and exchanging information about horses and riding.
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| 7. |
- Byrkjedal, Per Thomas, et al.
(författare)
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Simulated Game-Based Ice Hockey Match Design (Scrimmage) Elicits Greater Intensity in External Load Parameters Compared With Official Matches
- 2022
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Ingår i: Frontiers in Sports and Active Living. - Lausanne : Frontiers Media S.A.. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Objective: A limited number of studies have explored the external load experienced in indoor sports such as ice hockey, and few the link between training and match performance. As a paucity exists within this topic, this study explored whether a simulated match design (i.e., scrimmage) could be representative of official match demands and elicit similar external loads as in official matches in a group of elite youth male ice hockey players.Methods: A total of 26 players were monitored during eight official and four simulation matches using a Local Positioning System. Total distance, max velocity, slow (0–10.9 km/h), moderate (11–16.9 km/h), high (17.0–23.9 km/h), and sprint (>24 km/h) speed skating distance, distance per min, PlayerLoadTM, PlayerLoadTM per min, high-intensity events (HIEs) (>2.5 m/s−2), acceleration (ACCs), decelerations (DECs), and change of directions (CODs) were extracted from the tracking devices. A two-level regression analysis was conducted to compare the difference between match types when controlling for time on ice, match day, and position.Results: Between match-type results showed a credible difference in all variables except max velocity and ACCs. Distance per min was 27.3% higher during simulation matches and was explained by a 21.3, 24.1, and 14.8% higher distance in sprint-, high-, and moderate speed skating distance, while slow speed-skating distance was 49.2% lower and total distance only trivially different from official to simulation matches. Total PlayerLoadTM was 11.2% lower, while PlayerLoadTM per min was 8.5% higher during simulation matches. HIEs, CODs, and DECs were 10.0, 11.9, and 22.3% higher during simulation matches.Conclusion: The simulated match design is related to official match demands with comparable match-time, playing time, number of shifts, and shift duration. However, simulation matches provoked a higher external load output compared with official matches, possibly explained by a more continuous movement design. A game-based simulation match design can therefore be utilized when match-related actions at high intensity are warranted. © 2022 Byrkjedal, Luteberge, Bjørnsen, Ivarsson and Spencer.
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| 8. |
- Carlsson, Tomas, et al.
(författare)
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The Modern Double-Poling Technique Is Not More Energy Efficient Than the Old-Fashioned Double-Poling Technique at a Submaximal Work Intensity
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media SA. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the study was to investigate whether there are energy-efficiency differences between the execution of the old-fashioned double-poling technique (DPOLD) and the modern double-poling technique (DPMOD) at a submaximal work intensity among elite male cross-country skiers. Fifteen elite male cross-country skiers completed two 4-min tests at a constant mechanical work rate (MWR) using the DPMOD and DPOLD. During the last minute of each test, the mean oxygen uptake (VO2) and respiratory exchange ratio (RER) were analyzed, from which the metabolic rate (MR) and gross efficiency (GE) were calculated. In addition, the difference between pretest and posttest blood-lactate concentrations (BLadiff) was determined. For each technique, skiers’ joint angles (i.e., heel, ankle, knee, hip, shoulder, and elbow) were analyzed at the highest and lowest positions during the double-poling cycle. Paired-samples t-tests were used to investigate differences between DPMOD and DPOLD outcomes. There were no significant differences in either VO2mean, MR, GE, or BLadiff (all P > 0.05) between the DPMOD and DPOLD tests. DPMOD execution was associated with a higher RER (P < 0.05). Significant technique-specific differences were found in either the highest and/or the lowest position for all six analyzed joint angles (all P < 0.001). Hence, despite decades of double-poling technique development, which is reflected in the significant biomechanical differences between DPOLD and DPMOD execution, at submaximal work intensity, the modern technique is not more energy efficient than the old-fashioned technique.
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| 9. |
- Fahrenholtz, Ida Lysdahl, et al.
(författare)
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Risk of Low Energy Availability, Disordered Eating, Exercise Addiction, and Food Intolerances in Female Endurance Athletes
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media S.A.. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Relative energy deficiency in sport (RED-S) is a complex syndrome describing health and performance consequences of low energy availability (LEA) and is common among female endurance athletes. Various underlying causes of LEA have been reported, including disordered eating behavior (DE), but studies investigating the association with exercise addiction and food intolerances are lacking. Therefore, the aim of this cross-sectional study was to investigate the association between DE, exercise addiction and food intolerances in athletes at risk of LEA compared to those with low risk. Female endurance athletes, 18-35 years, training >= 5 times/week were recruited in Norway, Sweden, Ireland, and Germany. Participants completed an online-survey comprising the LEA in Females Questionnaire (LEAF-Q), Exercise Addiction Inventory (EAI), Eating Disorder Examination Questionnaire (EDE-Q), and questions regarding food intolerances. Of the 202 participants who met the inclusion criteria and completed the online survey, 65% were at risk of LEA, 23% were at risk of exercise addiction, and 21% had DE. Athletes at risk of LEA had higher EDE-Q and EAI scores compared to athletes with low risk. EAI score remained higher in athletes with risk of LEA after excluding athletes with DE. Athletes at risk of LEA did not report more food intolerances (17 vs. 10%, P = 0.198), but were more frequently reported by athletes with DE (28 vs. 11%, P = 0.004). In conclusion, these athletes had a high risk of LEA, exercise addiction, and DE. Exercise addiction should be considered as an additional risk factor in the prevention, early detection, and targeted treatment of RED-S among female endurance athletes.
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| 10. |
- Gunnarsson, Björn, et al.
(författare)
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Understanding exercise addiction, psychiatric characteristics and use of anabolic androgenic steroids among recreational athletes - An online survey study.
- 2022
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Ingår i: Frontiers in Sports and Active Living. - : Frontiers Media S.A.. - 2624-9367. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Background: The purpose of this paper was to explore maladaptive behaviors among physically active individuals, including exercise dependence and use of anabolic steroids. Both exercise addiction (EA) and use of anabolic androgenic steroids (AAS) correlate to high amounts of exercise and EA have been linked to eating disorders and other mental health problems.Methods: An internet survey was spread through fitness-related social media. Inclusion criteria were age ≥ 15 years and exercise frequency ≥ thrice weekly. Exercise addiction inventory identified those at-risk of EA (rEA). Characteristics of rEA were compared to those not at risk. In a separate analysis, AAS users were compared to AAS-naïve individuals.Results: In total, 3,029 participants completed the questionnaire. Of these, 11% screened positive for being rEA, and 23% for ED. Factors associated with EA included daily exercise, social phobia, eating disorders and OCD. Risk consumption of alcohol was a negative predictor. Thirty seven participants had taken AAS the last year. These were mainly men, bodybuilders/powerlifters and more often used amphetamines and opioids.Discussion: This exploratory study supports EA being strongly associated with eating disorders. Identified associations between EA and compulsive or anxiety disorders warrant further research to clarify if these associations arise prior to, together with, or secondary to EA.
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