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Engan, Harald K.
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Publications (10 of 29) Show all publications
Rodríguez-Zamora, L., Engan, H. K., Lodin-Sundström, A., Schagatay, F., Iglesias, X., Rodriguez, F. A. & Schagatay, E. (2018). Blood lactate accumulation during competitive freediving and synchronized swimming. Undersea & Hyperbaric Medicine, 45(1), 55-63
Open this publication in new window or tab >>Blood lactate accumulation during competitive freediving and synchronized swimming
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2018 (English)In: Undersea & Hyperbaric Medicine, ISSN 1066-2936, Vol. 45, no 1, p. 55-63Article in journal (Refereed) Published
Abstract [en]

A number of competitive water sports are performed while breath-holding (apnea). Such performances put large demands on the anaerobic system, but the study of lactate accumulation in apneic sports is limited. We therefore aimed to determine and compare the net lactate accumulation (NLA) during competition events in six disciplines of competitive freediving (FD) and three disciplines of synchronized swimming (SSW). The FD disciplines were: static apnea (STA; n = 14) dynamic apnea (DYN; n = 19) dynamic apnea no fins (DNF; n = 16) constant weight (CWT; n = 12) constant weight no fins (CNF; n = 8) free immersion (FIM; n =10) The SSW disciplines were solo (n = 21), duet (n = 31) and team (n = 34). Capillary blood lactate concentration was measured before and three minutes after competition performances, and apneic duration and performance variables were recorded. In all nine disciplines NLA was observed. The highest mean (SD) NLA (mmol.L-1) was found in CNF at 6.3 (2.2), followed by CWT at 5.9 (2.3) and SSW solo at 5 (1.9). STA showed the lowest NLA 0.7 (0.7) mmol.L-1 compared to all other disciplines (P < 0.001). The NLA recorded shows that sports involving apnea involve high levels of anaerobic activity. The highest NLA was related to both work done by large muscle groups and long apneic periods, suggesting that NLA is influenced by both the type of work and apnea duration, with lower NLA in SSW due to shorter apneic episodes with intermittent breathing.

Keywords
apnea, anaerobic, breath-hold diving, exercise, hypoxia, underwater, sports
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-33680 (URN)000431654400008 ()29571233 (PubMedID)2-s2.0-85060948755 (Scopus ID)
Available from: 2018-05-31 Created: 2018-05-31 Last updated: 2019-03-19Bibliographically approved
Patrician, A., Engan, H. K., Lundsten, D., Grote, L., Vigetun-Haughey, H. & Schagatay, E. (2018). The Effect of Dietary Nitrate on Nocturnal Sleep-Disordered Breathing and Arterial Oxygen Desaturation at High Altitude. High Altitude Medicine & Biology, 19(1), 21-27
Open this publication in new window or tab >>The Effect of Dietary Nitrate on Nocturnal Sleep-Disordered Breathing and Arterial Oxygen Desaturation at High Altitude
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2018 (English)In: High Altitude Medicine & Biology, ISSN 1527-0297, E-ISSN 1557-8682, Vol. 19, no 1, p. 21-27Article in journal (Refereed) Published
Abstract [en]

Patrician, Alexander, Harald Engan, David Lundsten, Ludger Grote, Helena Vigetun-Haughey, and Erika Schagatay. The effect of dietary nitrate on nocturnal sleep-disordered breathing and arterial oxygen desaturation at high altitude. High Alt Med Biol 00:000-000, 2017.Sleep-disordered breathing and fluctuations in arterial oxygen saturation (SaO(2)) are common during sleep among lowlanders ascending to high altitude. Dietary nitrate (NO3-) supplementation has been shown to lower the O-2 consumption in various conditions. Our objective was to investigate whether dietary NO3- could reduce sleep-disordered breathing and SaO(2) desaturation during sleep at altitude. Cardiorespiratory responses during sleep were measured in 10 healthy lowlanders at 330m and then again in the Himalayas at 3700-4900m. Each subject received two 70mL shots of either beetroot juice (BR; approximate to 5.0mmol NO3- per shot) or placebo (PL: approximate to 0.003mmol NO3- per shot) in a single-blinded, weighted order over two consecutive nights at altitude. At 2.5-4.5 hours into sleep at altitude, BR increased the SaO(2) desaturation drop (4.2 [0.1]% with PL vs. 5.3 [0.4]% with BR; p=0.024) and decreased the SaO(2) desaturation duration (14.1 [0.9] seconds with PL to 11.1 [0.9] seconds with BR; p=0.0.041). There was a reduction in breaths with flow limitation (p=0.025), but no changes in Apnea-Hypopnea Index (AHI), mean and minimum SaO(2). The study suggests BR supplementation does not improve AHI or oxygenation, but may increase fluctuations in arterial O-2 saturation during sleep at altitude in native lowlanders.

Keywords
arterial oxygen desaturation, dietary nitrate, hypobaric hypoxia, pulmonary vasculature, sleep at high altitude
National Category
Sport and Fitness Sciences
Identifiers
urn:nbn:se:miun:diva-32569 (URN)10.1089/ham.2017.0039 (DOI)000417305600001 ()2-s2.0-85044988132 (Scopus ID)
Available from: 2017-12-21 Created: 2017-12-21 Last updated: 2019-08-06Bibliographically approved
Schagatay, E., Patrician, A., Engan, H. & Lodin-Sundström, A. (2017). Spleen Contraction and Hb Increase after Nitrate Ingestion may Explain Enhanced Apneic Diving Performance. Paper presented at Scandinavian Physiological Society Meeting in Oslo, Norway, 26-28 August 2016. Acta Physiologica, 219(S710), 32-32, Article ID P-42.
Open this publication in new window or tab >>Spleen Contraction and Hb Increase after Nitrate Ingestion may Explain Enhanced Apneic Diving Performance
2017 (English)In: Acta Physiologica, ISSN 1748-1708, E-ISSN 1748-1716, Vol. 219, no S710, p. 32-32, article id P-42Article in journal, Meeting abstract (Refereed) Published
Abstract [en]

INTRODUCTION: Ingesting nitrate-rich beetroot juice (BJ) has been suggested to enhance physical performance by reducing the oxygen cost, which could be useful in apneic diving. We previously found that after ingestion of BJ, arterial oxygen saturation was higher after static apneas (Engan et.al, Resp. Physiol & Neurobiol, 2012) and after dynamic apneas involving exercise (Patrician & Schagatay. Scand.J.Med.Sci.Sports, 2016). Our aim was to investigate the effect of BJ ingestion on spleen contraction and the resulting Hb increase, a mechanism known to prolong apneas (Schagatay et.al, J.Appl.Physiol, 2001).

MATERIALS AND METHODS: Eight volunteers aged 24±2 years simulated diving by performing maximal apneas with face immersion during prone rest ~2.5h after ingesting 70 ml BJ (5 mmol NO3-) or placebo (0.003 mmol NO3-) on separate days in a weighted order. We measured spleen diameters for volume calculation and capillary Hb before and after "dives".

RESULTS: Baseline (mean±SE) spleen volume was 269±33 mL with placebo and 206±27 mL after BJ ingestion (P<0.05). Post "dive" spleen volumes were smaller, but similar at 168±35 mL and 193±25 mL, respectively (NS). Baseline Hb was 145.4±3.4 g/L with placebo and 149.8±2.6 g/L with BJ (P<0.05). Post "dive" Hb had increased to 152.0±4.8 g/L with placebo and 153.7±3.0 g/L with BJ (NS). 

CONCLUSION: With BJ ingestion spleen volume was reduced and Hb elevated even before the "dive". The elevated Hb at the start of apnea would likely have a positive effect on apneic duration by enhancing circulating oxygen stores. The positive effect of nitrate on performance in various sports could in part be due to its spleen-emptying effect, causing a natural blood boosting, which is a novel finding.

National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-29758 (URN)000393916600067 ()
Conference
Scandinavian Physiological Society Meeting in Oslo, Norway, 26-28 August 2016
Available from: 2016-12-22 Created: 2016-12-22 Last updated: 2017-12-14Bibliographically approved
Engan, H. K., Hilmarsen, C., Sittlinger, S., Sandmael, J. A., Skanke, F. & Oldervoll, L. M. (2016). Are web-based questionnaires accepted in patients attending rehabilitation?. Disability and Rehabilitation, 38(24-26), 2406-2412
Open this publication in new window or tab >>Are web-based questionnaires accepted in patients attending rehabilitation?
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2016 (English)In: Disability and Rehabilitation, ISSN 0963-8288, E-ISSN 1464-5165, Vol. 38, no 24-26, p. 2406-2412Article in journal (Refereed) Published
Abstract [en]

Purpose: The aim of the present paper was to study preferences for web based self-administered questionnaires (web SAQs) vs. paper-based self-administered questionnaires (paper SAQs) and to evaluate the feasibility of using web SAQs in patients referred to cardiac, lung, occupational and cancer rehabilitation programs. Methods: The patients were approached by mail and given the choice to answer the compulsory SAQs either on paper or on a web-based platform. Results: Hundred and twenty seven out of 183 eligible patients (69.3%) were willing to participate and 126 completed the study. Web SAQs were preferred by 77.7%, and these patients were significantly younger, more often cohabiting and tended to have higher level of education than paper SAQ users. Mean number of data missing per patient was less among the web SAQ users than the paper SAQ users (0.55 vs. 2.15, p <0.001). Costs related to human resources were estimated to be 60% lower with web SAQs compared to paper SAQs. Conclusions: Web SAQs were well accepted among the patients scheduled for rehabilitation, led to less missing data and considerable cost savings related to human resources. Patients referred to rehabilitation should be offered the choice to complete self-administered questionnaires on internet platforms when internet access is common and available.

Keywords
Costs, e-health, health logistics, internet
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-29291 (URN)10.3109/09638288.2015.1129449 (DOI)000385478900008 ()26800715 (PubMedID)2-s2.0-84955060785 (Scopus ID)
Available from: 2016-11-14 Created: 2016-11-14 Last updated: 2017-11-29Bibliographically approved
Bakker, E., Engan, H., Patrician, A., Schagatay, E., Karlsen, T., Wisloff, U. & Gaustad, S. E. (2015). Acute dietary nitrate supplementation improves arterial endothelial function at high altitude: A double-blinded randomized controlled cross over study. Nitric oxide, 50, 58-64
Open this publication in new window or tab >>Acute dietary nitrate supplementation improves arterial endothelial function at high altitude: A double-blinded randomized controlled cross over study
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2015 (English)In: Nitric oxide, ISSN 1089-8603, E-ISSN 1089-8611, Vol. 50, p. 58-64Article in journal (Refereed) Published
Abstract [en]

Introduction: Dietary nitrate (NO3-) supplementation serves as an exogenous source of nitrite (NO3-) and nitric oxide (NO) through the NO3- NO3- NO pathway, and may improve vascular functions during normoxia. The effects of NO3- supplementation in healthy lowlanders during hypobaric hypoxia are unknown. Purpose: Determine the effect of acute oral NO3- supplementation via beetroot juice (BJ) on endothelial function (flow mediated dilation; FMD) in lowlanders at 3700 m. Methods: FMD was measured using ultrasound and Doppler in the brachial artery of 11 healthy subjects (4 females, age 25 +/- 5 yrs; height 1.8 +/- 0.1 m, weight 72 +/- 10 kg) sojourning to high altitude. In a randomized, double-blinded crossover study design, FMD was measured 3 h after drinking BJ (5.0 mmol NO3-) and placebo (PL; 0.003 mmol No-3(-)) supplementation at 3700 m, with a 24-h wash out period between tests. FMD was also measured without any BJ supplementation pre-trek at 1370 m, after 5 days at 4200 m and upon return to 1370 m after 4 weeks of altitude exposure (above 2500 m). The altitude exposure was interrupted by a decent to lower altitude where subjects spent two nights at 1370 m before returning to altitude again. Results: Ten subjects completed the NO3- supplementation. FMD (mean +/- SD) pre-trek value was 6.53 +/- 2.32% at 1370 m. At 3700 m FMD was reduced to 3.84 +/- 1.31% (p < 0.01) after PL supplementation but was normalized after receiving BJ (5.77 +/- 1.14% (p = 1.00). Eight of the subjects completed the interrupted 4-week altitude stay, and their FMD was lower at 4200 m (FMD 3.04 +/- 2.22%) and at post-altitude exposure to 1370 m (FMD 3.91 +/- 2.58%) compared to pre-trek FMD at 1370 m. Conclusion: Acute dietary NO3- supplementation may abolish altitude-induced reduction in endothelial function, and can serve as a dietary strategy to ensure peripheral vascular function in lowland subjects entering high altitude environments. (C) 2015 Elsevier Inc. All rights reserved.

Keywords
Nitric oxide, Beetroot juice, Field-study, FMD, Flow mediated dilation, Nepal, Altitude medicine
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-26568 (URN)10.1016/j.niox.2015.08.006 (DOI)000363362900008 ()2-s2.0-84941336858 (Scopus ID)
Available from: 2015-12-17 Created: 2015-12-17 Last updated: 2017-12-01Bibliographically approved
Engan, H. K. (2015). Cardiovascular, hematological and dietary means to cope with environmentally induced hypoxia in humans. (Doctoral dissertation). Östersund: Mid Sweden University
Open this publication in new window or tab >>Cardiovascular, hematological and dietary means to cope with environmentally induced hypoxia in humans
2015 (English)Doctoral thesis, comprehensive summary (Other academic)
Place, publisher, year, edition, pages
Östersund: Mid Sweden University, 2015. p. 87
Series
Mid Sweden University doctoral thesis, ISSN 1652-893X ; 213
National Category
Sport and Fitness Sciences Physiology
Identifiers
urn:nbn:se:miun:diva-25016 (URN)978-91-88025-01-2 (ISBN)
Supervisors
Available from: 2015-06-01 Created: 2015-06-01 Last updated: 2018-01-11Bibliographically approved
Engan, H. K., Lodin-Sundström, A. & Schagatay, E. (2015). Comparison of two methods potentially reducing metabolism during apnea. In: : . Paper presented at EUBS conference, Amsterdam 19-22 August, 2015.
Open this publication in new window or tab >>Comparison of two methods potentially reducing metabolism during apnea
2015 (English)Conference paper, Poster (with or without abstract) (Refereed)
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-26744 (URN)
Conference
EUBS conference, Amsterdam 19-22 August, 2015
Available from: 2015-12-28 Created: 2015-12-28 Last updated: 2015-12-28Bibliographically approved
Rodríguez-Zamora, L., Lodin-Sundström, A., Engan, H. K., Höök, M., Patrician, A., Degerström, E. & Schagatay, E. (2015). Effects of altitude acclimatization on spleen volume and contraction during submaximal and maximal work in lowlanders. In: : . Paper presented at 20th Annual Congress of the European College of Sport Science (ECSS), Malmö, June 24-27, 2015.
Open this publication in new window or tab >>Effects of altitude acclimatization on spleen volume and contraction during submaximal and maximal work in lowlanders
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2015 (English)Conference paper, Oral presentation with published abstract (Refereed)
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-26743 (URN)
Conference
20th Annual Congress of the European College of Sport Science (ECSS), Malmö, June 24-27, 2015
Available from: 2015-12-28 Created: 2015-12-28 Last updated: 2016-04-25Bibliographically approved
Lodin-Sundström, A., Engan, H. K. & Schagatay, E. (2015). Mechanisms underlying spleen contraction during apneic diving. In: : . Paper presented at EUBS conference, Amsterdam 19-22 August, 2015.
Open this publication in new window or tab >>Mechanisms underlying spleen contraction during apneic diving
2015 (English)Conference paper, Oral presentation with published abstract (Refereed)
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-26745 (URN)
Conference
EUBS conference, Amsterdam 19-22 August, 2015
Available from: 2015-12-28 Created: 2015-12-28 Last updated: 2015-12-28Bibliographically approved
Johansson, H., Engan, H. K., Melin, M., Patrician, A., Lodin-Sundström, A. & Schagatay, E. (2015). No effect of dietary nitrate on the human diving response in dry and wet apneas. In: : . Paper presented at 20th Annual Congress of the European College of Sport Science (ECSS), Malmö, June 24-27, 2015..
Open this publication in new window or tab >>No effect of dietary nitrate on the human diving response in dry and wet apneas
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2015 (English)Conference paper, Oral presentation with published abstract (Refereed)
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-26739 (URN)
Conference
20th Annual Congress of the European College of Sport Science (ECSS), Malmö, June 24-27, 2015.
Available from: 2015-12-28 Created: 2015-12-23 Last updated: 2016-04-25Bibliographically approved
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