miun.sePublikationer
Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Increase of hemoglobin concentration after maximal apneas in divers, skiers and untrained humans
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
Mittuniversitetet, Fakulteten för humanvetenskap, Institutionen för hälsovetenskap. (Nationellt Vintersportcentrum / Swedish Winter Sports Research Centre)ORCID-id: 0000-0002-3814-6246
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap. (Nationellt Vintersportcentrum / Swedish Winter Sports Research Centre)
Visa övriga samt affilieringar
2005 (Engelska)Ingår i: Canadian Journal of Applied Physiology, ISSN 1066-7814, Vol. 30, nr 3, s. 276-281Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Apnea is physiologically stressful and can within a short time frame pose a threat to survival. To sustain prolonged apnea, oxygen use should be minimized and its storage maximized. Two mechanisms known to have this effect are the cardiovascular diving response, directing the available oxygen selectively to the heart and brain, and spleen contraction increasing the circulating erythrocyte volume and thereby gas storage capacity. Spleen contraction is also observed after maximal exercise, and is thought to enhance aerobic performance. While the cardiovascular diving response is known to be more pronounced after apnea training, spleen contraction has not been studied in conjunction with apnea training or other types of training. The aim of the present investigation is to study the hematological responses to apnea performed during rest by elite apneic divers, by elite cross-country skiers and by untrained subjects. After 20 min of rest, subjects performed 3 maximal apneas spaced by 2 min normal breathing intervals. Blood samples were drawn before, directly after, and 10 min after the apnea series and hemoglobin concentration was measured. All groups responded to maximal apneas with an increase in hemoglobin concentration, which had disappeared after 10 min of recovery. The increase in hemoglobin concentration was more pronounced in the apneic divers (4g/L) than in skiers (3g/L) and untrained subjects (2g/L; P < 0.05). All groups prolonged their apneic times through the series, but the increase was most evident for the divers versus both the skiers (P < 0.05) and untrained subjects (P < 0.01). The results suggest that these responses could be more pronounced as a result of apnea training.

Ort, förlag, år, upplaga, sidor
2005. Vol. 30, nr 3, s. 276-281
Nyckelord [en]
apnea, hemoglobin, endurance training, cross country skiing, spleen contraction
Nationell ämneskategori
Mikrobiologi Biologiska vetenskaper Idrottsvetenskap
Identifikatorer
URN: urn:nbn:se:miun:diva-1688ISI: 000229602800002Lokalt ID: 1516OAI: oai:DiVA.org:miun-1688DiVA, id: diva2:26720
Anmärkning
VR-Medicine, ExternalTillgänglig från: 2008-09-30 Skapad: 2009-07-27 Senast uppdaterad: 2011-04-06Bibliografiskt granskad
Ingår i avhandling
1. Hematological changes arising from spleen contraction during apnea and altitude in humans
Öppna denna publikation i ny flik eller fönster >>Hematological changes arising from spleen contraction during apnea and altitude in humans
2008 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Ort, förlag, år, upplaga, sidor
Östersund: Mid Sweden University, 2008. s. 49
Serie
Mid Sweden University doctoral thesis, ISSN 1652-893X ; 57
Nyckelord
Hypoxia, hypercapnia, hemoglobin, hematocrit, breath-hold diving
Nationell ämneskategori
Mikrobiologi Idrottsvetenskap Fysiologi
Identifikatorer
urn:nbn:se:miun:diva-7786 (URN)978-91-86073-03-9 (ISBN)
Disputation
(Engelska)
Handledare
Tillgänglig från: 2009-07-09 Skapad: 2008-12-15 Senast uppdaterad: 2018-01-13Bibliografiskt granskad
2. Cardiovascular and hematological responses to voluntary apnea in humans
Öppna denna publikation i ny flik eller fönster >>Cardiovascular and hematological responses to voluntary apnea in humans
2007 (Engelska)Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
Abstract [en]

This thesis deals with cardiovascular and hematological responses to voluntary apnea in

humans, with a special focus on O2 usage and storage. Humans, and many other air‐breathing

animals, respond to apnea (breath holding) with a collection of interacting cardiovascular

reflexes, which are collectively called the diving response. In humans, the main characteristics of

the diving response are a reduction in heart rate (bradycardia), decreased cardiac output,

peripheral vasoconstriction and increased arterial blood pressure. Another response during

apnea in mammals, more recently also observed in man, is a transient increase in hemoglobin

concentration across a series of apneas, probably due a reduction in spleen size. There may also

be long‐term effects on erythropoiesis in the apneic diver, as suggested by high hemoglobin

levels observed in divers. The focus of the included studies are the short transient diving

response (I), the more slowly occurring transient hematological changes to apnea, most likely

related to a reduction in spleen size (II), and the possible effects of repeated apnea on serum

erythropoietin concentration (III).

I) The aim was to study the effects of body immersion on the O2‐conserving effect of the

human diving response. The results showed that, regardless of body immersion, apnea with face

immersion causes a stronger cardiovascular diving response compared to during apnea alone,

leading to a smaller reduction in arterial oxygen saturation levels. Thus the diving response is

triggered and conserves O2 even during whole‐body immersion, which has previously only been

observed during apnea without whole‐body immersion.

II) The aim was to study hematological responses to voluntary repeated maximal‐duration

apneas in divers and non‐divers. Increases in hemoglobin concentration were found across a

series of 3 apneas in elite breath‐hold divers, elite cross‐country skiers and untrained subjects.

However a larger increase in hemoglobin was found in divers compared to non‐divers, which

suggests a possible training effect of their extensive apnea‐specific training. In contrast, physical

endurance training does not appear to affect the hematological response to apnea.

III) The aim was to study the effects of serial voluntary apnea on the serum erythropoietin

concentration. In a comparison between elite breath‐hold divers and subjects untrained in apnea,

divers were found to have a 5% higher resting hemoglobin concentration. An average maximum

increase in erythropoietin of 24 % was found in untrained subjects after 15 maximal duration

apneas, preceded by 1 min of hyperventilation. This suggests a possible erythropoietic effect of

apnea‐induced hypoxia, which may connect the increased resting hemoglobin found in divers to

their apnea‐specific training.

It was concluded from these studies that man responds to apnea with a series of different

adjustments in order to limit O2 usage and increase O2 storage: The classical diving response is

effectively restricting O2‐consumption also during full immersion, the spleen related hemoglobin

increase occurs in both divers and non‐divers with different levels of physiological training, but

is more prominent in divers, and finally, the observed high levels of hemoglobin concentration in

divers may be related to enhanced erythropoiesis during dive training.

Ort, förlag, år, upplaga, sidor
Sundsvall: Mittuniversitetet, 2007. s. 47
Serie
Mid Sweden University licentiate thesis, ISSN 1652-8948 ; 28
Nationell ämneskategori
Mikrobiologi
Identifikatorer
urn:nbn:se:miun:diva-9328 (URN)978-91-85317-70-7 (ISBN)
Presentation
(Engelska)
Tillgänglig från: 2009-07-10 Skapad: 2009-07-10 Senast uppdaterad: 2011-04-05Bibliografiskt granskad

Open Access i DiVA

Fulltext saknas i DiVA

Personposter BETA

Richardson, Matthewde Bruijn, RobertHolmberg, Hans-ChristerBjörklund, GlennHaughey, HelenaSchagatay, Erika

Sök vidare i DiVA

Av författaren/redaktören
Richardson, Matthewde Bruijn, RobertHolmberg, Hans-ChristerBjörklund, GlennHaughey, HelenaSchagatay, Erika
Av organisationen
Institutionen för naturvetenskapInstitutionen för hälsovetenskap
MikrobiologiBiologiska vetenskaperIdrottsvetenskap

Sök vidare utanför DiVA

GoogleGoogle Scholar

urn-nbn

Altmetricpoäng

urn-nbn
Totalt: 1166 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf