miun.sePublications
Change search
Link to record
Permanent link

Direct link
BETA
Lodin-Sundström, Angelica
Alternative names
Publications (10 of 48) Show all publications
Holmström, P., Mulder, E., Lodin-Sundström, A., Limbu, P. & Schagatay, E. (2019). The Magnitude of Diving Bradycardia During Apnea at Low-Altitude Reveals Tolerance to High Altitude Hypoxia. Frontiers in Physiology, 10, 1-12, Article ID 1075.
Open this publication in new window or tab >>The Magnitude of Diving Bradycardia During Apnea at Low-Altitude Reveals Tolerance to High Altitude Hypoxia
Show others...
2019 (English)In: Frontiers in Physiology, ISSN 1664-042X, E-ISSN 1664-042X, Vol. 10, p. 1-12, article id 1075Article in journal (Refereed) Published
Abstract [en]

Acute mountain sickness (AMS) is a potentially life-threatening illness that may develop during exposure to hypoxia at high altitude (HA). Susceptibility to AMS is highly individual, and the ability to predict it is limited. Apneic diving also induces hypoxia, and we aimed to investigate whether protective physiological responses, i.e., the cardiovascular diving response and spleen contraction, induced during apnea at low-altitude could predict individual susceptibility to AMS. Eighteen participants (eight females) performed three static apneas in air, the first at a fixed limit of 60 s (A1) and two of maximal duration (A2-A3), spaced by 2 min, while SaO(2), heart rate (HR) and spleen volume were measured continuously. Tests were conducted in Kathmandu (1470 m) before a 14 day trek to mount Everest Base Camp (5360 m). During the trek, participants reported AMS symptoms daily using the Lake Louise Questionnaire (LLQ). The apnea-induced HR-reduction (diving bradycardia) was negatively correlated with the accumulated LLQ score in A1 (r(s) = -0.628, p= 0.005) and A3 (r(s) = -0.488, p = 0.040) and positively correlated with SaO(2) at 4410 m (A1: r = 0.655, p = 0.003; A2: r = 0.471, p = 0.049; A3: r = 0.635, p = 0.005). Baseline spleen volume correlated negatively with LLQ score (r(s) = -0.479, p = 0.044), but no correlation was found between apnea-induced spleen volume reduction with LLQ score (r(s) = 0.350, p = 0.155). The association between the diving bradycardia and spleen size with AMS symptoms suggests links between physiological responses to HA and apnea. Measuring individual responses to apnea at sea-level could provide means to predict AMS susceptibility prior to ascent.

Keywords
acute mountain sickness, breath-hold diving, hypoxia, prediction, cardiovascular diving response, spleen
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-37117 (URN)10.3389/fphys.2019.01075 (DOI)000482202400001 ()2-s2.0-85072189253 (Scopus ID)
Available from: 2019-09-05 Created: 2019-09-05 Last updated: 2019-09-24Bibliographically approved
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
Show others...
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
Barlow, M. J., Elia, A., Shannon, O. M., Zacharogianni, A. & Lodin-Sundström, A. (2018). The Effect of a Dietary Nitrate Supplementation in the Form of a Single Shot of Beetroot Juice on Static and Dynamic Apnea Performance. International Journal of Sport Nutrition & Exercise Metabolism, 28(5), 497-501
Open this publication in new window or tab >>The Effect of a Dietary Nitrate Supplementation in the Form of a Single Shot of Beetroot Juice on Static and Dynamic Apnea Performance
Show others...
2018 (English)In: International Journal of Sport Nutrition & Exercise Metabolism, ISSN 1526-484X, E-ISSN 1543-2742, Vol. 28, no 5, p. 497-501Article in journal (Refereed) Published
Abstract [en]

The purpose of the present study was to assess the effects of acute nitrate (NO3-)-rich beetroot juice (BRJ) supplementation on peripheral oxygen saturation (SpO(2)), heart rate (HR), and pulmonary gas exchange during submaximal static and dynamic apnea. Methods: Nine (six males and three females) trained apneists (age: 39.6 +/- 8.2 years, stature: 170.4 +/- 11.5 cm, and body mass: 72.0 +/- 11.5 kg) performed three submaximal static apneas at 60%, 70%, and 80% of the participant's current reported personal best time, followed by three submaximal (similar to 75% or personal best distance) dynamic apneas following the consumption of either a 70-ml concentrated BRJ (7.7 mmol NO3-) or a NO3--depleted placebo (PLA; 0.1 mmol NO3-) in doubleblind randomized manner. HR and SpO(2) were measured via fingertip pulse oximetry at the nadir, and online gas analysis was used to assess pulmonary oxygen uptake ((V)over dotO2) during recovery following breath-holds. Results: There were no differences (p < .05) among conditions for HR (PLA = 59 +/- 11 bpm and BRJ = 61 +/- 12 bpm), SpO(2) (PLA = 83% +/- 14% and BRJ = 84% +/- 9%), or (V)over dotO2 (PLA = 1.00 +/- 0.22 L/min and BRJ = 0.97 +/- 0.27 L/min). Conclusion: The consumption of 7.7 mmol of beetroot juice supplementation prior to a series of submaximal static and dynamic apneas did not induce a significant change in SpO(2), HR, and (V)over dotO2 when compared with placebo. Therefore, there is no apparent physiological response that may benefit free divers as a result of the supplementation.

Keywords
breath-hold, ergogenic aid, free diving
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-34728 (URN)10.1123/ijsnem.2017-0300 (DOI)000445902500008 ()29091471 (PubMedID)2-s2.0-85054452946 (Scopus ID)
Available from: 2018-10-16 Created: 2018-10-16 Last updated: 2018-12-06Bibliographically 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
Rodríguez-Zamora, L., Patrician, A., Starfelt, V., Olander, C., Lodin-Sundström, A. & Schagatay, E. (2016). Physiological responses to apnea at sea level predict SaO2 at simulated 5300 m altitude. In: : . Paper presented at 8th European Hypoxia Symposium: High altitude and isobaric hypoxia influence on human performance: science and practice, Police, Slovenia, 8 - 11 September 2016.
Open this publication in new window or tab >>Physiological responses to apnea at sea level predict SaO2 at simulated 5300 m altitude
Show others...
2016 (English)Conference paper, Oral presentation with published abstract (Refereed)
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-29760 (URN)
Conference
8th European Hypoxia Symposium: High altitude and isobaric hypoxia influence on human performance: science and practice, Police, Slovenia, 8 - 11 September 2016
Available from: 2016-12-22 Created: 2016-12-22 Last updated: 2016-12-22Bibliographically 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
Show others...
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
Schagatay, E. & Hubinette, A. (2015). Exercise induce hemoconcentration following spleen contraction in subjects with COPD. COPD Research and practice, 1, 1-7, Article ID 13.
Open this publication in new window or tab >>Exercise induce hemoconcentration following spleen contraction in subjects with COPD
2015 (English)In: COPD Research and practice, ISSN 2054-9040, Vol. 1, p. 1-7, article id 13Article in journal (Refereed) Published
Abstract [en]

The blood-boosting spleen contraction represents a potential protective response to hypoxia by raising the blood gas storage capacity. Human spleen contraction has been observed during exercise, apnea and simulated altitude resulting in ejection of stored red blood cells into circulation. High-altitude exposure has been shown to increase spleen contraction suggesting that long-term hypoxia may improve the response in humans. Subjects with COPD are often exposed to hypoxia, which limits their physical performance. However, it is not known if spleen contraction occurs in subjects with COPD. Our aim was to reveal whether subjects with COPD recruit the spleen erythrocyte reserve during mild exercise.

Methods

SpO2, spleen volume and Hb were measured before and after 6 min walking test (6MWT) in 24 subjects with COPD. Results were analyzed for all subjects pooled and for subject groups with resting SpO2 above and below 90 % separated and expressed as mean.

Results

6MWT reduced SpO2 from 91 to 83 % and spleen volume from 254 to 181 mL, while Hb increased from 150 to 154 g/L (p = 0.001 for all). Compared to subjects with SpO2 > 90 %, the group with SpO2 < 90 % displayed the largest resting spleen volume (339 vs 202 mL; p = 0.001) and the most pronounced spleen volume reduction (139 vs 40 mL; p = 0.007).

Conclusion

Exercise with hypoxia evokes spleen contraction in subjects with COPD and may represent a protective response during periods of hypoxia. The larger spleen volume and more pronounced contraction in the most hypoxic subjects may suggest long-term adaptation to hypoxia.

National Category
Sport and Fitness Sciences
Identifiers
urn:nbn:se:miun:diva-29632 (URN)10.1186/s40749-015-0015-9 (DOI)
Available from: 2016-12-16 Created: 2016-12-16 Last updated: 2019-09-16Bibliographically approved
Lodin, A. (2015). Initiation of spleen contraction resulting in natural blood boosting in humans. (Doctoral dissertation). Östersund: Mid Sweden University
Open this publication in new window or tab >>Initiation of spleen contraction resulting in natural blood boosting in humans
2015 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The spleen has been shown to contract in apneic situations in humans as well as in other diving mammals, expelling its stored red blood cell content into circulation. This natural blood boosting may increase the circulating hemoglobin concentration (Hb) by up to 10%, which would enhance the oxygen carrying capacity and likely increase performance. However, the triggers of this response in humans have not been fully clarified. Study I was therefore focused on the effect of hypoxia as a trigger of spleen contraction. It was found that 20 min of normobaric hypoxic breathing evoked a substantial reduction in spleen volume showing that hypoxia is an important trigger for spleen contraction. Knowing the role of hypoxia, Study II compared two different hypoxic situations – a 2 min apnea and 20 min normobaric hypoxic breathing – which resulted in the same level of arterial hemoglobin desaturation. Apnea evoked a twice as great spleen volume reduction, implying that variables other than hypoxia were likely involved in triggering spleen contraction. This may be hypercapnia which is present during apnea but not during normobaric hypoxic breathing. Study III therefore investigated the effects of breathing gas mixtures containing different proportions of CO2 prior to maximal apneas. Pre-breathing mixtures with higher percentages of CO2 resulted in greater spleen contraction, thus demonstrating hypercapnia's likely role as a trigger in addition to hypoxia. Study IV explored whether an all-or-nothing threshold stimulus for triggering spleen contraction existed, or if contraction was graded in relation to the magnitude of triggering stimuli. Exercise was therefore performed in an already hypoxic state during normobaria. Rest in hypoxia produced a moderate spleen volume reduction, with an enhanced spleen contraction resulting after hypoxic exercise, with a concomitant increase in Hb. This implies that spleen contraction is a graded response related to the magnitude of the stimuli. This could be beneficial in environments with varying oxygen content or work loads. Study V examined the possibility that spleen contraction is part of the acclimatization to altitude, during an expedition to summit Mt Everest. The long-term high altitude exposure, combined with physical work on the mountain, had no effects on resting spleen volume but resulted in a stronger spleen contraction, when provoked by apnea or exercise. This indicates that acclimatization to altitude may enhance the contractile capacity of the spleen, which may be beneficial for the climber. From these studies I concluded that hypoxia is an important trigger for spleen contraction but that hypercapnia also contributes in apneic situations. The spleen contraction likely provides a graded expulsion of erythrocytes in response to these stimuli, causing a temporary increase in gas storage capacity that may facilitate activities such as freediving and climbing. The storage of erythrocytes during rest serves to reduce blood viscosity, which would also be beneficial for the climber or diver. The human spleen contraction appears to become stronger with acclimatization, with beneficial effects at altitude. Such an upgraded response could be beneficial both in sports and diseases involving hypoxia.

Place, publisher, year, edition, pages
Östersund: Mid Sweden University, 2015. p. 87
Series
Mid Sweden University doctoral thesis, ISSN 1652-893X ; 217
Keywords
Acclimatization, altitude, apnea, breath-hold diving, hemoglobin, hypercapnia, hypoxia, triggers
National Category
Health Sciences
Identifiers
urn:nbn:se:miun:diva-25518 (URN)978-91-88025-10-4 (ISBN)
Supervisors
Available from: 2015-07-13 Created: 2015-07-13 Last updated: 2017-06-15Bibliographically 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
Organisations

Search in DiVA

Show all publications