Kristin Lundanes Jonvik

• Weijer, Vera C.R.; Jonvik, Kristin Lundanes; van Dam, Lotte; Risvang, Linn; Raastad, Truls & van Loon, Luc J.C. [Vis alle 7 forfattere av denne artikkelen] (2024). Measured and Predicted Resting Metabolic Rate of Dutch and Norwegian Paralympic Athletes. Journal of the Academy of Nutrition and Dietetics. ISSN 2212-2672. doi: 10.1016/j.jand.2024.05.010.
• Weijer, Vera C.R.; van Dijk, Jan-Willem; van Dam, Lotte; Risvang, Linn; Bons, Judith & Raastad, Truls [Vis alle 8 forfattere av denne artikkelen] (2024). Do Paralympic athletes suffer from brittle bones? Prevalence and risk factors of low bone mineral density in Paralympic athletes. Bone Reports. ISSN 2352-1872. 21. doi: 10.1016/j.bonr.2024.101767.
• Weijer, Vera C. R.; Jonvik, Kristin Lundanes; Van Dam, Lotte; Risvang, Linn; Plasqui, Guy & Sandbakk, Øyvind Bucher [Vis alle 9 forfattere av denne artikkelen] (2024). Energy Requirements of Paralympic Athletes: Insights from the Doubly Labeled Water Approach. Medicine & Science in Sports & Exercise. ISSN 0195-9131. 56(5), s. 963–971. doi: 10.1249/MSS.0000000000003379.
• Jonvik, Kristin Lundanes; Torstveit, Monica Klungland; Sundgot-Borgen, Jorunn & Mathisen, Therese Fostervold (2022). Do we need to change the guideline values for determining low bone mineral density in athletes? [Viewpoint]. Journal of applied physiology. ISSN 8750-7587. 132(5), s. 1320–1322. doi: 10.1152/japplphysiol.00851.2021. Fulltekst i vitenarkiv
• van Venrooij, Niek F.J.; Wardenaar, Floris C.; Hoogervorst, Daan; Senden, Joan M.G.; van Dijk, Jan-Willem & Jonvik, Kristin Lundanes (2022). The association between gastrointestinal injury, complaints, and food intake in 60-km ultramarathon runners. Applied Physiology, Nutrition and Metabolism. ISSN 1715-5312. 47(5), s. 547–554. doi: 10.1139/apnm-2021-0711. Fulltekst i vitenarkiv Vis sammendrag

  We aimed to assess the association between gastrointestinal (GI) injury, complaints, and food intake in 60-km ultramarathon runners. Thirty-three ultramarathon runners provided pre- and post-race blood samples for assessment of GI injury by intestinal fatty-acid binding protein (I-FABP), and inflammatory response by interleukin (IL)-6, IL-8, tumour necrosis factor alpha (TNF-α), and C-reactive protein (CRP). GI complaints and nutritional intake were reported by a post-race questionnaire. GI complaints were reported by 73% of the runners, of which 20% reported 1 or 2 severe complaints. IL-6, IL8, TNF-α, and CRP increased significantly from pre- to post-race (P < 0.001 for all biomarkers), while I-FABP did not (1375 [IQR: 1264–2073] to 1726 [IQR: 985–3287] pg/mL; P = 0.330). The ‘GI complaints score’, as the integral of the number and severity of GI complaints, did not correlate with ΔI-FABP (rs: –0.050, P = 0.790) or energy intake (rs: 0.211, P = 0.260). However, there was a significant negative correlation between energy intake and ΔI-FABP (rs: –0.388, P = 0.031). In conclusion, GI complaints were neither associated with food intake nor GI injury as assessed by plasma I-FABP response. Energy intake, however, was inversely related to the I-FABP response to exercise. This finding suggests that substantial energy intakes during exercise may prevent exercise-induced GI injury as assessed by the I-FABP response.

• Shannon, Oliver M.; Allen, Jason D.; Bescos, Raul; Burke, Louise; Clifford, Tom & Easton, Chris [Vis alle 16 forfattere av denne artikkelen] (2022). Dietary Inorganic Nitrate as an Ergogenic Aid: An Expert Consensus Derived via the Modified Delphi Technique. Sports Medicine. ISSN 0112-1642. 52(10), s. 2537–2558. doi: 10.1007/s40279-022-01701-3. Fulltekst i vitenarkiv Vis sammendrag

  Introduction: Dietary inorganic nitrate is a popular nutritional supplement, which increases nitric oxide bioavailability and may improve exercise performance. Despite over a decade of research into the effects of dietary nitrate supplementation during exercise there is currently no expert consensus on how, when and for whom this compound could be recommended as an ergogenic aid. Moreover, there is no consensus on the safe administration of dietary nitrate as an ergogenic aid. This study aimed to address these research gaps. Methods: The modified Delphi technique was used to establish the views of 12 expert panel members on the use of dietary nitrate as an ergogenic aid. Over three iterative rounds (two via questionnaire and one via videoconferencing), the expert panel members voted on 222 statements relating to dietary nitrate as an ergogenic aid. Consensus was reached when > 80% of the panel provided the same answer (i.e. yes or no). Statements for which > 80% of the panel cast a vote of insufficient evidence were categorised as such and removed from further voting. These statements were subsequently used to identify directions for future research. Results: The 12 panel members contributed to voting in all three rounds. A total of 39 statements (17.6%) reached consensus across the three rounds (20 yes, 19 no). In round one, 21 statements reached consensus (11 yes, 10 no). In round two, seven further statements reached consensus (4 yes, 3 no). In round three, an additional 11 statements reached consensus (5 yes, 6 no). The panel agreed that there was insufficient evidence for 134 (60.4%) of the statements, and were unable to agree on the outcome of the remaining statements. Conclusions: This study provides information on the current expert consensus on dietary nitrate, which may be of value to athletes, coaches, practitioners and researchers. The effects of dietary nitrate appear to be diminished in individuals with a higher aerobic fitness (peak oxygen consumption [V̇O2peak] > 60 ml/kg/min), and therefore, aerobic fitness should be taken into account when considering use of dietary nitrate as an ergogenic aid. It is recommended that athletes looking to benefit from dietary nitrate supplementation should consume 8–16 mmol nitrate acutely or 4–16 mmol/day nitrate chronically (with the final dose ingested 2–4 h pre-exercise) to maximise ergogenic effects, taking into consideration that, from a safety perspective, athletes may be best advised to increase their intake of nitrate via vegetables and vegetable juices. Acute nitrate supplementation up to ~ 16 mmol is believed to be safe, although the safety of chronic nitrate supplementation requires further investigation. The expert panel agreed that there was insufficient evidence for most of the appraised statements, highlighting the need for future research in this area.

• Jonvik, Kristin Lundanes; Vardardottir, Birna & Broad, Elizabeth (2022). How Do We Assess Energy Availability and RED-S Risk Factors in Para Athletes? Nutrients. ISSN 2072-6643. 14(5). doi: 10.3390/nu14051068. Fulltekst i vitenarkiv Vis sammendrag

  Low energy availability (LEA) is considered to be the underlying cause of a number of maladaptations in athletes, including impaired physiological function, low bone mineral density (BMD), and hormonal dysfunction. This is collectively referred to as ‘Relative Energy Deficiency in Sport’ (RED-S). LEA is calculated through assessment of dietary energy intake (EI), exercise energy expenditure (EEE) and fat-free mass (FFM). The incidence of LEA in Paralympic athletes is relatively unknown; however, there are legitimate concerns that Para athletes may be at even higher risk of LEA than able-bodied athletes. Unfortunately, there are numerous issues with the application of LEA assessment tools and the criterion for diagnosis within the context of a Para population. The calculation of EEE, in particular, is limited by a distinct lack of published data that cover a range of impairments and activities. In addition, for several RED-S-related factors, it is difficult to distinguish whether they are truly related to LEA or a consequence of the athlete’s impairment and medical history. This narrative review outlines deficits and complexities when assessing RED-S and LEA in Para athletes, presents the information that we do have, and provides suggestions for future progress in this important area of sports nutrition.

• Jonvik, Kristin Lundanes; Torstveit, Monica Klungland; Sundgot-Borgen, Jorunn & Mathisen, Therese Fostervold (2022). Last Word on Viewpoint: Do we need to change the guideline values for determining low bone mineral density in athletes? Journal of applied physiology. ISSN 8750-7587. 132(5), s. 1325–1326. doi: 10.1152/japplphysiol.00227.2022.

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• Baumgart, Julia Kathrin; Jonvik, Kristin Lundanes; Severin, Anna Cecilia; Hrozanova, Maria & Solli, Guro Strøm (2023). Parautøveren. I Sandbakk, Øyvind Bucher; Solli, Guro Strøm & Staff, Hanne Cesilie (Red.), Den kvinnelige idrettsutøveren. Fagbokforlaget. ISSN 9788245036930.
• Mathisen, Therese Fostervold; Jonvik, Kristin Lundanes & Kjellgren, Daniel (2022). "Det grønne skiftet". [Avis]. Aftenposten.

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