1
|
Webb KL, Gorman EK, Morkeberg OH, Klassen SA, Regimbal RJ, Wiggins CC, Joyner MJ, Hammer SM, Senefeld JW. The relationship between hemoglobin and [Formula: see text]: A systematic review and meta-analysis. PLoS One 2023; 18:e0292835. [PMID: 37824583 PMCID: PMC10569622 DOI: 10.1371/journal.pone.0292835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 09/29/2023] [Indexed: 10/14/2023] Open
Abstract
OBJECTIVE There is widespread agreement about the key role of hemoglobin for oxygen transport. Both observational and interventional studies have examined the relationship between hemoglobin levels and maximal oxygen uptake ([Formula: see text]) in humans. However, there exists considerable variability in the scientific literature regarding the potential relationship between hemoglobin and [Formula: see text]. Thus, we aimed to provide a comprehensive analysis of the diverse literature and examine the relationship between hemoglobin levels (hemoglobin concentration and mass) and [Formula: see text] (absolute and relative [Formula: see text]) among both observational and interventional studies. METHODS A systematic search was performed on December 6th, 2021. The study procedures and reporting of findings followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Article selection and data abstraction were performed in duplicate by two independent reviewers. Primary outcomes were hemoglobin levels and [Formula: see text] values (absolute and relative). For observational studies, meta-regression models were performed to examine the relationship between hemoglobin levels and [Formula: see text] values. For interventional studies, meta-analysis models were performed to determine the change in [Formula: see text] values (standard paired difference) associated with interventions designed to modify hemoglobin levels or [Formula: see text]. Meta-regression models were then performed to determine the relationship between a change in hemoglobin levels and the change in [Formula: see text] values. RESULTS Data from 384 studies (226 observational studies and 158 interventional studies) were examined. For observational data, there was a positive association between absolute [Formula: see text] and hemoglobin levels (hemoglobin concentration, hemoglobin mass, and hematocrit (P<0.001 for all)). Prespecified subgroup analyses demonstrated no apparent sex-related differences among these relationships. For interventional data, there was a positive association between the change of absolute [Formula: see text] (standard paired difference) and the change in hemoglobin levels (hemoglobin concentration (P<0.0001) and hemoglobin mass (P = 0.006)). CONCLUSION These findings suggest that [Formula: see text] values are closely associated with hemoglobin levels among both observational and interventional studies. Although our findings suggest a lack of sex differences in these relationships, there were limited studies incorporating females or stratifying results by biological sex.
Collapse
Affiliation(s)
- Kevin L. Webb
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Ellen K. Gorman
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Olaf H. Morkeberg
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Stephen A. Klassen
- Department of Kinesiology, Brock University, St. Catharines, Ontario, Canada
| | - Riley J. Regimbal
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Chad C. Wiggins
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Michael J. Joyner
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Shane M. Hammer
- Department of Kinesiology, Applied Health, and Recreation, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - Jonathon W. Senefeld
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois
| |
Collapse
|
2
|
Mancera-Soto EM, Ramos-Caballero DM, Rojas J. JA, Duque L, Chaves-Gomez S, Cristancho-Mejía E, Schmidt WFJ. Hemoglobin Mass, Blood Volume and VO2max of Trained and Untrained Children and Adolescents Living at Different Altitudes. Front Physiol 2022; 13:892247. [PMID: 35721534 PMCID: PMC9204197 DOI: 10.3389/fphys.2022.892247] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 04/18/2022] [Indexed: 11/13/2022] Open
Abstract
Introduction: To a considerable extent, the magnitude of blood volume (BV) and hemoglobin mass (Hbmass) contribute to the maximum O2-uptake (VO2max), especially in endurance-trained athletes. However, the development of Hbmass and BV and their relationships with VO2max during childhood are unknown. The aim of the present cross-sectional study was to investigate Hbmass and BV and their relationships with VO2max in children and adolescents. In addition, the possible influence of endurance training and chronic hypoxia was evaluated.Methods: A total of 475 differently trained children and adolescents (girls n = 217, boys n = 258; untrained n = 171, endurance trained n = 304) living at two different altitudes (∼1,000 m, n = 204, ∼2,600 m, n = 271) and 9–18 years old participated in the study. The stage of puberty was determined according to Tanner; Hbmass and BV were determined by CO rebreathing; and VO2max was determined by cycle ergometry and for runners on the treadmill.Results: Before puberty, there was no association between training status and Hbmass or BV. During and after puberty, we found 7–10% higher values in the trained groups. Living at a moderate altitude had a uniformly positive effect of ∼7% on Hbmass in all groups and no effect on BV. The VO2max before, during and after puberty was strongly associated with training (pre/early puberty: boys +27%, girls +26%; mid puberty: +42% and +45%; late puberty: +43% and +47%) but not with altitude. The associated effects of training in the pre/early pubertal groups were independent of Hbmass and BV, while in the mid- and late pubertal groups, 25% of the training effect could be attributed to the elevated Hbmass.Conclusions: The associated effects of training on Hbmass and BV, resulting in increased VO2max, can only be observed after the onset of puberty.
Collapse
Affiliation(s)
- Erica Mabel Mancera-Soto
- Departamento del Movimiento Corporal Humano, Facultad de Medicina, Universidad Nacional de Colombia, Bogotá, Colombia
- Department of Sports Medicine and Sports Physiology, University of Bayreuth, Bayreuth, Germany
| | - Diana Marcela Ramos-Caballero
- Departamento de Biología, Facultad de Ciencias, Universidad Nacional de Colombia, Bogotá, Colombia
- Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, Colombia
| | - Joel A. Rojas J.
- Programa de Licenciatura en Educación Física Recreación y Deporte, Facultad de Ciencias de la Educación, Unidad Central del Valle del Cauca, Tuluá, Colombia
| | - Lohover Duque
- Programa de Licenciatura en Educación Física Recreación y Deporte, Facultad de Ciencias de la Educación, Unidad Central del Valle del Cauca, Tuluá, Colombia
| | - Sandra Chaves-Gomez
- Laboratorio de Control al Dopaje, Ministerio del Deporte de Colombia, Bogotá, Colombia
| | - Edgar Cristancho-Mejía
- Departamento de Biología, Facultad de Ciencias, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Walter Franz-Joachim Schmidt
- Department of Sports Medicine and Sports Physiology, University of Bayreuth, Bayreuth, Germany
- *Correspondence: Walter Franz-Joachim Schmidt,
| |
Collapse
|
3
|
A Comparative Study of Hematological Parameters of Endurance Runners at Guna Athletics Sport Club (3100 Meters above Sea Level) and Ethiopian Youth Sport Academy (2400 Meters above Sea Level), Ethiopia. JOURNAL OF SPORTS MEDICINE 2021; 2021:8415100. [PMID: 34869775 PMCID: PMC8635926 DOI: 10.1155/2021/8415100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 10/19/2021] [Accepted: 11/05/2021] [Indexed: 11/17/2022]
Abstract
Introduction. Endurance running performance is dependent upon hematological, physiological, anthropometrical, diet, genetic, and training characteristics. Increased oxygen transport and efficiency of tissue in extracting oxygen are the major determinants to competitions that require endurance. Thus, altitude training is often employed to increase blood oxygen-carrying capacity to improve sea-level endurance performance. This study aimed to compare hematological parameters of endurance runners’ training at different clubs with different altitudes (Guna Athletics Sport Club at Guna (3100 meter above sea level) and Ethiopian Youth Sport Academy at Addis Ababa (2400 meter above sea level)). Methods. A comparative cross-sectional study was conducted at GASC and EYSA. Data were collected from a total of 102 eligible study subjects (26 runners and 25 controls at Guna and 26 runners and 25 controls at Addis Ababa) from May to October 2019. About 3 ml of the venous blood was drawn from the antecubital vein by aseptic procedure and analyzed using a hematology analyzer (DIRUI BCC-3000B, China). One-way ANOVA and independent-sample t-tests were used to compare means. Result. Male runners in Guna had significantly higher hemoglobin (Hgb), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and white blood cell (WBC) count than male runners in Addis Ababa. Besides, female runners in Guna had significantly higher MCH and MCHC than female runners in Addis Ababa. However, there were no significant differences between Guna and Addis Ababa runners in red blood cell (RBC) count, Hct, MCV, and platelet count in both sexes, while Hgb and WBC count in females. Conclusion. Decisively, Guna Athletics Sport Club endurance runners had significantly higher hematological parameters than Ethiopian Youth Sport Academy endurance runners. This provides invaluable information for coaches and sport physicians to monitor the hematological profile and the health status of an athlete living and training at different altitudes.
Collapse
|
4
|
Christou GA, Pagourelias ED, Deligiannis AP, Kouidi EJ. Exploring the Anthropometric, Cardiorespiratory, and Haematological Determinants of Marathon Performance. Front Physiol 2021; 12:693733. [PMID: 34539429 PMCID: PMC8446630 DOI: 10.3389/fphys.2021.693733] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 08/11/2021] [Indexed: 11/13/2022] Open
Abstract
Aim We aimed to investigate the main anthropometric, cardiorespiratory and haematological factors that can determine marathon race performance in marathon runners. Methods Forty-five marathon runners (36 males, age: 42 ± 10 years) were examined during the training period for a marathon race. Assessment of training characteristics, anthropometric measurements, including height, body weight (n = 45) and body fat percentage (BF%) (n = 33), echocardiographic study (n = 45), cardiopulmonary exercise testing using treadmill ergometer (n = 33) and blood test (n = 24) were performed. We evaluated the relationships of these measurements with the personal best marathon race time (MRT) within a time frame of one year before or after the evaluation of each athlete. Results The training age regarding long-distance running was 9 ± 7 years. Training volume was 70 (50-175) km/week. MRT was 4:02:53 ± 00:50:20 h. The MRT was positively associated with BF% (r = 0.587, p = 0.001). Among echocardiographic parameters, MRT correlated negatively with right ventricular end-diastolic area (RVEDA) (r = -0.716, p < 0.001). RVEDA was the only independent echocardiographic predictor of MRT. With regard to respiratory parameters, MRT correlated negatively with maximum minute ventilation indexed to body surface area (VEmax/BSA) (r = -0.509, p = 0.003). Among parameters of blood test, MRT correlated negatively with haemoglobin concentration (r = -0.471, p = 0.027) and estimated haemoglobin mass (Hbmass) (r = -0.680, p = 0.002). After performing multivariate linear regression analysis with MRT as dependent variable and BF% (standardised β = 0.501, p = 0.021), RVEDA (standardised β = -0.633, p = 0.003), VEmax/BSA (standardised β = 0.266, p = 0.303) and Hbmass (standardised β = -0.308, p = 0.066) as independent variables, only BF% and RVEDA were significant independent predictors of MRT (adjusted R2 = 0.796, p < 0.001 for the model). Conclusions The main physiological determinants of better marathon performance appear to be low BF% and RV enlargement. Upregulation of both maximum minute ventilation during exercise and haemoglobin mass may have a weaker effect to enhance marathon performance. Clinical Trial Registration www.ClinicalTrials.gov, identifier NCT04738877.
Collapse
Affiliation(s)
- Georgios A Christou
- Laboratory of Sports Medicine, Sports Medicine Division, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Efstathios D Pagourelias
- Laboratory of Sports Medicine, Sports Medicine Division, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Asterios P Deligiannis
- Laboratory of Sports Medicine, Sports Medicine Division, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Evangelia J Kouidi
- Laboratory of Sports Medicine, Sports Medicine Division, Aristotle University of Thessaloniki, Thessaloniki, Greece
| |
Collapse
|
5
|
Baart AM, Klein Gunnewiek JMT, Balvers MGJ, Zwerver J, Vergouwen PCJ. Pitfalls in interpreting red blood cell parameters in elite high-altitude and sea-level athletes: A unique case series. Physiol Rep 2021; 9:e14891. [PMID: 34197694 PMCID: PMC8248916 DOI: 10.14814/phy2.14891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 05/10/2021] [Indexed: 11/24/2022] Open
Abstract
Standard routine hematological measurements are commonly used to investigate differences in blood parameters between high-altitude athletes (HAA) and sea-level athletes (SLA), and to monitor the effect of high-altitude training. In this way, red blood cell (RBC) parameters are usually expressed as relative parameters (concentration) rather than absolute parameters (total amount). In this unique case series of elite HAA and SLA, we describe how different ways of parameter expression can affect the interpretation of blood tests. In a group of 42 elite athletes, relative and absolute RBC parameters were compared between HAA and SLA. Absolute parameters were calculated by multiplying relative values with formula-based estimated blood volume (BV-e). Additionally, in two individual athletes, one HAA and one SLA, absolute parameters were also calculated with blood volume (BV) obtained by measurement with a dilution method (BV-m). In men, HAA had a significantly higher hemoglobin (Hb) concentration (+7.8%; p = 0.001) and total Hb mass per kg body weight (BW) (+12.0%; p = 0.002). When not corrected for BW, HAA had a lower, non-significant, total Hb mass (-7.8%; p = 0.055). In women, no significant differences between HLA and SLA were observed. The two individual athletes showed that, based on BV-m, in the HAA, total Hb mass and total Hb mass per kg BW were respectively 14.1% and 31.0% higher than in the SLA, whereas based on BV-e, in the HAA, total Hb mass was 20.8% lower and total Hb mass per kg BW was only 2.4% higher. Similar inconsistencies were observed for total RBC count. Thus, different ways of parameter expression, and different methods of BV assessment for the calculation of absolute parameter values, influence the interpretation of blood tests in athletes, which may lead to misinterpretation and incorrect conclusions.
Collapse
Affiliation(s)
- A. Mireille Baart
- Clinical Chemistry and Haematology LaboratoryGelderse Vallei HospitalEdethe Netherlands
- Present address:
Division of Human Nutrition and HealthWageningen University & ResearchWageningenthe Netherlands
| | | | - Michiel G. J. Balvers
- Clinical Chemistry and Haematology LaboratoryGelderse Vallei HospitalEdethe Netherlands
- Present address:
Division of Human Nutrition and HealthWageningen University & ResearchWageningenthe Netherlands
| | - Johannes Zwerver
- Department of Elite Sports Medicine and Sports MedicineGelderse Vallei HospitalEdethe Netherlands
- Center for Human Movement SciencesUniversity Medical Center GroningenGroningenthe Netherlands
| | - Peter C. J. Vergouwen
- Department of Elite Sports Medicine and Sports MedicineGelderse Vallei HospitalEdethe Netherlands
| |
Collapse
|
6
|
Koivisto-Mørk AE, Svendsen IS, Skattebo Ø, Hallén J, Paulsen G. Impact of baseline serum ferritin and supplemental iron on altitude-induced hemoglobin mass response in elite athletes. Scand J Med Sci Sports 2021; 31:1764-1773. [PMID: 33908091 DOI: 10.1111/sms.13982] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 03/26/2021] [Accepted: 04/16/2021] [Indexed: 01/05/2023]
Abstract
The present study explored the impact of pre-altitude serum (s)-ferritin and iron supplementation on changes in hemoglobin mass (ΔHbmass) following altitude training. Measures of Hbmass and s-ferritin from 107 altitude sojourns (9-28 days at 1800-2500 m) with world-class endurance athletes (males n = 41, females n = 25) were analyzed together with iron supplementation and self-reported illness. Altitude sojourns with a hypoxic dose [median (range)] of 1169 (912) km·h increased Hbmass (mean ± SD) 36 ± 38 g (3.7 ± 3.7%, p < 0.001) and decreased s-ferritin -11 (190) µg·L-1 (p = 0.001). Iron supplements [27 (191) mg·day-1 ] were used at 45 sojourns (42%), while only 11 sojourns (10%) were commenced with s-ferritin <35 µg/L. Hbmass increased by 4.6 ± 3.7%, 3.4 ± 3.3%, 4.2 ± 4.3%, and 2.9 ± 3.4% with pre-altitude s-ferritin ≤35 µg·L-1 , 36-50 µg·L-1 , 51-100 µg·L-1 , and >100 µg·L-1 , respectively, with no group difference (p = 0.400). Hbmass increased by 4.1 ± 3.9%, 3.0 ± 3.0% and 3.7 ± 4.7% without, ≤50 mg·day-1 or >50 mg·day-1 supplemental iron, respectively (p = 0.399). Linear mixed model analysis revealed no interaction between pre-altitude s-ferritin and iron supplementation on ΔHbmass (p = 0.906). However, each 100 km·h increase in hypoxic dose augmented ΔHbmass by an additional 0.4% (95% CI: 0.1-0.7%; p = 0.012), while each 1 g·kg-1 higher pre-altitude Hbmass reduced ΔHbmass by -1% (-1.6 to -0.5; p < 0.001), and illness lowered ΔHbmass by -5.7% (-8.3 to -3.1%; p < 0.001). In conclusion, pre-altitude s-ferritin or iron supplementation were not related to the altitude-induced increase in Hbmass (3.7%) in world-class endurance athletes with clinically normal iron stores.
Collapse
Affiliation(s)
- Anu Elisa Koivisto-Mørk
- Norwegian Olympic Sports Centre, Norwegian Olympic and Paralympic Committee and Confederation of Sports, Oslo, Norway
| | - Ida Siobhan Svendsen
- Norwegian Olympic Sports Centre, Norwegian Olympic and Paralympic Committee and Confederation of Sports, Oslo, Norway
| | - Øyvind Skattebo
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Jostein Hallén
- Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| | - Gøran Paulsen
- Norwegian Olympic Sports Centre, Norwegian Olympic and Paralympic Committee and Confederation of Sports, Oslo, Norway.,Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway
| |
Collapse
|
7
|
Mukai K, Ohmura H, Takahashi Y, Kitaoka Y, Takahashi T. Four weeks of high-intensity training in moderate, but not mild hypoxia improves performance and running economy more than normoxic training in horses. Physiol Rep 2021; 9:e14760. [PMID: 33611843 PMCID: PMC7897453 DOI: 10.14814/phy2.14760] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 01/22/2021] [Accepted: 01/23/2021] [Indexed: 11/24/2022] Open
Abstract
We investigated whether horses trained in moderate and mild hypoxia demonstrate greater improvement in performance and aerobic capacity compared to horses trained in normoxia and whether the acquired training effects are maintained after 2 weeks of post‐hypoxic training in normoxia. Seven untrained Thoroughbred horses completed 4 weeks (3 sessions/week) of three training protocols, consisting of 2‐min cantering at 95% maximal oxygen consumption V˙O2max under two hypoxic conditions (H16, FIO2 = 16%; H18, FIO2 = 18%) and in normoxia (N21, FIO2 = 21%), followed by 2 weeks of post‐hypoxic training in normoxia, using a randomized crossover study design with a 3‐month washout period. Incremental treadmill tests (IET) were conducted at week 0, 4, and 6. The effects of time and groups were analyzed using mixed models. Run time at IET increased in H16 and H18 compared to N21, while speed at V˙O2max was increased significantly only in H16. V˙O2max in all groups and cardiac output at exhaustion in H16 and H18 increased after 4 weeks of training, but were not significantly different between the three groups. In all groups, run time, V˙O2max, VV˙O2max, Q˙max, and lactate threshold did not decrease after 2 weeks of post‐hypoxic training in normoxia. These results suggest that 4 weeks of training in moderate (H16), but not mild (H18) hypoxia elicits greater improvements in performance and running economy than normoxic training and that these effects are maintained for 2 weeks of post‐hypoxic training in normoxia.
Collapse
Affiliation(s)
- Kazutaka Mukai
- Equine Research Institute, Japan Racing Association, Shimotsuke, Japan
| | - Hajime Ohmura
- Equine Research Institute, Japan Racing Association, Shimotsuke, Japan
| | - Yuji Takahashi
- Equine Research Institute, Japan Racing Association, Shimotsuke, Japan
| | - Yu Kitaoka
- Kanagawa University, Yokohama, Kanagawa, Japan
| | | |
Collapse
|
8
|
Mairbäurl H, Gassmann M, Muckenthaler MU. Geographical ancestry affects normal hemoglobin values in high-altitude residents. J Appl Physiol (1985) 2020; 129:1451-1459. [PMID: 33002380 DOI: 10.1152/japplphysiol.00025.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Increasing the hemoglobin (Hb) concentration is a major mechanism adjusting arterial oxygen content to decreased oxygen partial pressure of inspired air at high altitude. Approximately 5% of the world's population living at altitudes higher than 1,500 m shows this adaptive mechanism. Notably, there is a wide variation in the extent of increase in Hb concentration among different populations. This short review summarizes available information on Hb concentrations of high-altitude residents living at comparable altitudes (3,500-4,500 m) in different regions of the world. An increased Hb concentration is found in all high-altitude populations. The highest mean Hb concentration was found in adult male Andean residents and in Han Chinese living at high altitude, whereas it was lowest in Ethiopians, Tibetans, and Sherpas. A lower plasma volume in Andean high-altitude natives may offer a partial explanation. Indeed, male Andean high-altitude natives have a lower plasma volume than Tibetans and Ethiopians. Moreover, Hb values were lower in adult, nonpregnant females than in males; differences between populations of different ancestry were less pronounced. Various genetic polymorphisms were detected in high-altitude residents thought to favor life in a hypoxic environment, some of which correlate with the relatively low Hb concentration in the Tibetans and Ethiopians, whereas differences in angiotensin-converting enzyme allele distribution may be related to elevated Hb in the Andeans. Taken together, these results indicate different sensitivity of oxygen dependent control of erythropoiesis or plasma volume among populations of different geographical ancestry, offering explanations for differences in the Hb concentration at high altitude.
Collapse
Affiliation(s)
- Heimo Mairbäurl
- Departmment of Translational Pneumology, University Hospital Heidelberg, Heidelberg, Germany.,Translational Lung Research Center Heidelberg, Member of the German Center for Lung Research, Heidelberg, Germany
| | - Max Gassmann
- Vetsuisse Faculty, Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland.,Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.,Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Martina U Muckenthaler
- Translational Lung Research Center Heidelberg, Member of the German Center for Lung Research, Heidelberg, Germany.,Departmment of Pediatric Hematology, Oncology and Immunology, University Hospital Heidelberg, Heidelberg, Germany.,Molecular Medicine Partnership Unit, University of Heidelberg, Heidelberg, Germany.,German Centre for Cardiovascular Research, Partner Site Heidelberg/Mannheim, Germany
| |
Collapse
|
9
|
Mairbäurl H. Kinetics of Changes in Hemoglobin After Ascent to and Return from High Altitude. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s42978-019-00044-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
10
|
Gassmann M, Mairbäurl H, Livshits L, Seide S, Hackbusch M, Malczyk M, Kraut S, Gassmann NN, Weissmann N, Muckenthaler MU. The increase in hemoglobin concentration with altitude varies among human populations. Ann N Y Acad Sci 2019; 1450:204-220. [PMID: 31257609 DOI: 10.1111/nyas.14136] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 05/02/2019] [Accepted: 05/16/2019] [Indexed: 02/06/2023]
Abstract
Decreased oxygen availability at high altitude requires physiological adjustments allowing for adequate tissue oxygenation. One such mechanism is a slow increase in the hemoglobin concentration ([Hb]) resulting in elevated [Hb] in high-altitude residents. Diagnosis of anemia at different altitudes requires reference values for [Hb]. Our aim was to establish such values based on published data of residents living at different altitudes by applying meta-analysis and multiple regressions. Results show that [Hb] is increased in all high-altitude residents. However, the magnitude of increase varies among the regions analyzed and among ethnic groups within a region. The highest increase was found in residents of the Andes (1 g/dL/1000 m), but this increment was smaller in all other regions of the world (0.6 g/dL/1000 m). While sufficient data exist for adult males and females showing that sex differences in [Hb] persist with altitude, data for infants, children, and pregnant women are incomplete preventing such analyses. Because WHO reference values were originally based on [Hb] of South American people, we conclude that individual reference values have to be defined for ethnic groups to reliably diagnose anemia and erythrocytosis in high-altitude residents. Future studies need to test their applicability for children of different ages and pregnant women.
Collapse
Affiliation(s)
- Max Gassmann
- Institute of Veterinary Physiology, Vetsuisse Faculty and Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland.,Universidad Peruana Cayetano Heredia (UPCH), Lima, Peru
| | - Heimo Mairbäurl
- Translational Lung Research Center Heidelberg (TLRC), the German Center for Lung Research (DZL), Heidelberg, Germany
| | - Leonid Livshits
- Institute of Veterinary Physiology, Vetsuisse Faculty and Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
| | - Svenja Seide
- Institute of Medical Biometry and Informatics (IMBI), University Hospital Heidelberg, Heidelberg, Germany
| | - Matthes Hackbusch
- Institute of Medical Biometry and Informatics (IMBI), University Hospital Heidelberg, Heidelberg, Germany
| | - Monika Malczyk
- Excellence Cluster Cardiopulmonary System, Justus-Liebig-University Giessen, University of Giessen and Marburg Lung Center, German Center for Lung Research (DZL), Heidelberg, Germany
| | - Simone Kraut
- Excellence Cluster Cardiopulmonary System, Justus-Liebig-University Giessen, University of Giessen and Marburg Lung Center, German Center for Lung Research (DZL), Heidelberg, Germany
| | - Norina N Gassmann
- Institute of Veterinary Physiology, Vetsuisse Faculty and Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
| | - Norbert Weissmann
- Excellence Cluster Cardiopulmonary System, Justus-Liebig-University Giessen, University of Giessen and Marburg Lung Center, German Center for Lung Research (DZL), Heidelberg, Germany
| | - Martina U Muckenthaler
- Pediatric Hematology, Oncology and Immunology, University Hospital Heidelberg, Molecular Medicine Partnership Unit, University of Heidelberg, Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research, Heidelberg, Germany
| |
Collapse
|
11
|
Abstract
High-level athletes are always looking at ways to maximize training adaptations for competition performance, and using altered environmental conditions to achieve this outcome has become increasingly popular by elite athletes. Furthermore, a series of potential nutrition and hydration interventions may also optimize the adaptation to altered environments. Altitude training was first used to prepare for competition at altitude, and it still is today; however, more often now, elite athletes embark on a series of altitude training camps to try to improve sea-level performance. Similarly, the use of heat acclimation/acclimatization to optimize performance in hot/humid environmental conditions is a common practice by high-level athletes and is well supported in the scientific literature. More recently, the use of heat training to improve exercise capacity in temperate environments has been investigated and appears to have positive outcomes. This consensus statement will detail the use of both heat and altitude training interventions to optimize performance capacities in elite athletes in both normal environmental conditions and extreme conditions (hot and/or high), with a focus on the importance of nutritional strategies required in these extreme environmental conditions to maximize adaptations conducive to competitive performance enhancement.
Collapse
|
12
|
Goodrich JA, Ryan BJ, Byrnes WC. The Influence of Oxygen Saturation on the Relationship Between Hemoglobin Mass and VO 2 max. Sports Med Int Open 2018; 2:E98-E104. [PMID: 30539125 PMCID: PMC6225968 DOI: 10.1055/a-0655-7207] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 05/11/2018] [Accepted: 06/05/2018] [Indexed: 11/04/2022] Open
Abstract
Hemoglobin mass (tHb) is a key determinant of maximal oxygen uptake (VO
2
max). We examined whether oxyhemoglobin desaturation (ΔS
a
O
2
) at VO
2
max modifies the relationship between tHb and VO
2
max at moderate altitude (1,625 m). Seventeen female and 16 male competitive, endurance-trained moderate-altitude residents performed two tHb assessments and two graded exercise tests on a cycle ergometer to determine VO
2
max and ΔS
a
O
2
. In males and females respectively, VO
2
max (ml·kg
−1
·min
−1
) ranged from 62.5–83.0 and 44.5–67.3; tHb (g·kg
−1
) ranged from 12.1–17.5 and 9.1–13.0; and S
a
O
2
at VO
2
max (%) ranged from 81.7–94.0 and 85.7–95.0. tHb was related to VO
2
max when expressed in absolute terms and after correcting for body mass (r=0.94 and 0.86, respectively); correcting by ΔS
a
O
2
did not improve these relationships (r=0.93 and 0.83). Additionally, there was a negative relationship between tHb and S
a
O
2
at VO
2
max (r=–0.57). In conclusion, across a range of endurance athletes at moderate altitude, the relationship between tHb and VO
2
max was found to be similar to that observed at sea level. However, correcting tHb by ΔS
a
O
2
did not explain additional variability in VO
2
max despite significant variability in ΔS
a
O
2
; this raises the possibility that tHb and exercise-induced ΔS
a
O
2
are not independent in endurance athletes.
Collapse
Affiliation(s)
- Jesse A Goodrich
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, United States
| | - Benjamin J Ryan
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, United States
| | - William C Byrnes
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, United States
| |
Collapse
|
13
|
Hawley JA, Lundby C, Cotter JD, Burke LM. Maximizing Cellular Adaptation to Endurance Exercise in Skeletal Muscle. Cell Metab 2018; 27:962-976. [PMID: 29719234 DOI: 10.1016/j.cmet.2018.04.014] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The application of molecular techniques to exercise biology has provided novel insight into the complexity and breadth of intracellular signaling networks involved in response to endurance-based exercise. Here we discuss several strategies that have high uptake by athletes and, on mechanistic grounds, have the potential to promote cellular adaptation to endurance training in skeletal muscle. Such approaches are based on the underlying premise that imposing a greater metabolic load and provoking extreme perturbations in cellular homeostasis will augment acute exercise responses that, when repeated over months and years, will amplify training adaptation.
Collapse
Affiliation(s)
- John A Hawley
- Exercise and Nutrition Research Program, Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC 3000, Australia.
| | - Carsten Lundby
- Centre for Physical Activity Research, Copenhagen University Hospital, Copenhagen, Denmark
| | - James D Cotter
- School of Physical Education, Sport and Exercise Sciences, University of Otago, Dunedin, New Zealand
| | - Louise M Burke
- Exercise and Nutrition Research Program, Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, VIC 3000, Australia; Department of Sport Nutrition, Australian Institute of Sport, Belconnen, ACT, Australia
| |
Collapse
|
14
|
Płoszczyca K, Langfort J, Czuba M. The Effects of Altitude Training on Erythropoietic Response and Hematological Variables in Adult Athletes: A Narrative Review. Front Physiol 2018; 9:375. [PMID: 29695978 PMCID: PMC5904371 DOI: 10.3389/fphys.2018.00375] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 03/27/2018] [Indexed: 02/02/2023] Open
Abstract
Background: One of the goals of altitude training is to increase blood oxygen-carrying capacity in order to improve sea-level endurance performance in athletes. The elevated erythropoietin (EPO) production in hypoxia is a key factor in the achievement of enhanced hematological variables. The level of the EPO increase and acceleration of erythropoiesis depend on the duration of exposure and degree of hypoxia. Furthermore, many other factors may affect the hematological response to altitude training. Aim: The purpose of this narrative review was to: (1) analyze the kinetics of EPO and hematological variables during and after altitude training; (2) summarize the current state of knowledge about the possible causes of individual or cohort differences in EPO and hematological response to altitude training; (3) formulate practical guidelines for athletes to improve the efficiency of altitude training. Methods: A narrative review was performed following an electronic search of the databases PubMed/MEDLINE and SPORTDiscus via EBSCO for all English-language articles published between 1997 and 2017. Results: Complete unification of results from studies on EPO kinetics was difficult due to different time and frequency of blood sampling by different researchers during and after altitude training, but the data presented in the reviewed literature allowed us to detect certain trends. The results of the reviewed studies were divergent and indicated either increase or no change of hematological variables following altitude training. Factors that may affect the hematological response to altitude training include hypoxic dose, training content, training background of athletes, and/or individual variability of EPO production. Conclusions: Despite the potential benefits arising from altitude training, its effectiveness in improving hematological variables is still debatable. Further research and better understanding of factors influencing the response to altitude, as well as factors affecting the suitable measurement and interpretation of study results, are needed.
Collapse
Affiliation(s)
- Kamila Płoszczyca
- Department of Sports Training, Academy of Physical Education of Katowice, Katowice, Poland
| | - Józef Langfort
- Department of Sports Training, Academy of Physical Education of Katowice, Katowice, Poland
| | - Miłosz Czuba
- Department of Physiology, Institute of Sport, Warsaw, Poland
| |
Collapse
|
15
|
Mairbäurl H. Neocytolysis: How to Get Rid of the Extra Erythrocytes Formed by Stress Erythropoiesis Upon Descent From High Altitude. Front Physiol 2018; 9:345. [PMID: 29674976 PMCID: PMC5896414 DOI: 10.3389/fphys.2018.00345] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 03/20/2018] [Indexed: 01/18/2023] Open
Abstract
Neocytolysis is the selective destruction of those erythrocytes that had been formed during stress-erythropoiesis in hypoxia in order to increase the oxygen transport capacity of blood. Neocytolysis likely aims at decreasing this excess amount of erythrocytes and hemoglobin (Hb) when it is not required anymore and to decrease blood viscosity. Neocytolysis seems to occur upon descent from high altitude. Similar processes seem to occur in microgravity, and are also discussed to mediate the replacement of erythrocytes containing fetal hemoglobin (HbF) with those having adult hemoglobin (HbA) after birth. This review will focus on hypoxia at high altitude. Hemoglobin concentration and total hemoglobin in blood increase by 20-50% depending on the altitude (i.e., the degree of hypoxia) and the duration of the sojourn. Upon return to normoxia hemoglobin concentration, hematocrit, and reticulocyte counts decrease faster than expected from inhibition of stress-erythropoiesis and normal erythrocyte destruction rates. In parallel, an increase in haptoglobin, bilirubin, and ferritin is observed, which serve as indirect markers of hemolysis and hemoglobin-breakdown. At the same time markers of progressing erythrocyte senescence appear even on reticulocytes. Unexpectedly, reticulocytes from hypoxic mice show decreased levels of the hypoxia-inducible factor HIF-1α and decreased activity of the BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3), which results in elevated mitochondrial activity in these cells. Furthermore, hypoxia increases the expression of miR-21, which inhibits the expression of catalase and thus decreases one of the most important mechanisms protecting against oxygen free radicals in erythrocytes. This unleashes a series of events which likely explain neocytolysis, because upon re-oxygenation systemic and mitochondrial oxygen radical formation increases and causes the selective destruction of those erythrocytes having impaired anti-oxidant capacity.
Collapse
Affiliation(s)
- Heimo Mairbäurl
- Medical Clinic VII, Sports Medicine, Translational Lung Research Center, German Center for Lung Research, University Hospital Heidelberg, Heidelberg, Germany
| |
Collapse
|
16
|
Prommer N, Wachsmuth N, Thieme I, Wachsmuth C, Mancera-Soto EM, Hohmann A, Schmidt WFJ. Influence of Endurance Training During Childhood on Total Hemoglobin Mass. Front Physiol 2018; 9:251. [PMID: 29618981 PMCID: PMC5871736 DOI: 10.3389/fphys.2018.00251] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 03/06/2018] [Indexed: 11/18/2022] Open
Abstract
Elite endurance athletes are characterized by markedly increased hemoglobin mass (Hbmass). It has been hypothesized that this adaptation may occur as a response to training at a very young age. Therefore, the aim of this study was to monitor changes in Hbmass in children aged 8–14 years following systematic endurance training. In the first study, Hbmass, VO2max, and lean body mass (LBM) were measured in 17 endurance-trained children (13 boys and 4 girls; aged 9.7 ± 1.3 years; training history 1.5±1.8 years; training volume 3.5 ± 1.6 h) twice a year for up to 3.5 years. The same parameters were measured once in a control group of 18 age-matched untrained children. Hbmass and blood volume (BV) were measured using the optimized CO-rebreathing technique, VO2max by an incremental test on a treadmill, and LBM by skin-fold measurements. In the second pilot study, the same parameters were measured in 9 young soccer athletes (aged 7.8 ± 0.2 years), and results were assessed in relation to soccer performance 2.5 years later. The increase in mean Hbmass during the period of study was 50% which was closely related to changes in LBM (r = 0.959). A significant impact of endurance training on Hbmass was observed in athletes exercising more than 4 h/week [+25.4 g compared to the group with low training volume (<2 h/week)]. The greatest effects were related to LBM (11.4 g·kg−1 LBM) and overlapped with the effects of age. A strong relationship was present between absolute Hbmass and VO2max (r = 0.939), showing that an increase of 1 g hemoglobin increases VO2max by 3.6 ml·min−1. Study 2 showed a positive correlation between Hbmass and soccer performance 2.5 years later at age 10.3 ± 0.3 years (r = 0.627, p = 0.035). In conclusion, children with a weekly training volume of more than 4 h show a 7% higher Hbmass than untrained children. Although this training effect is significant and independent of changes in LBM, the major factor driving the increase in Hbmass is still LBM.
Collapse
Affiliation(s)
- Nicole Prommer
- Department of Sports Medicine/Sports Physiology, Sports Science, University of Bayreuth, Universitaetsstrasse, Bayreuth, Germany
| | - Nadine Wachsmuth
- Department of Sports Medicine/Sports Physiology, Sports Science, University of Bayreuth, Universitaetsstrasse, Bayreuth, Germany
| | - Ina Thieme
- Department of Sports Medicine/Sports Physiology, Sports Science, University of Bayreuth, Universitaetsstrasse, Bayreuth, Germany
| | - Christian Wachsmuth
- Department of Sports Medicine/Sports Physiology, Sports Science, University of Bayreuth, Universitaetsstrasse, Bayreuth, Germany
| | - Erica M Mancera-Soto
- Department of Physiology, Biological Sciences, Universidad Nacional de Colombia, Bogota, Colombia
| | - Andreas Hohmann
- Department of Training Sciences, Sports Science, University of Bayreuth, Universitaetsstrasse, Bayreuth, Germany
| | - Walter F J Schmidt
- Department of Sports Medicine/Sports Physiology, Sports Science, University of Bayreuth, Universitaetsstrasse, Bayreuth, Germany
| |
Collapse
|
17
|
Laumets R, Viigipuu K, Mooses K, Mäestu J, Purge P, Pehme A, Kaasik P, Mooses M. Lower Leg Length is Associated with Running Economy in High Level Caucasian Distance Runners. J Hum Kinet 2017; 56:229-239. [PMID: 28469761 PMCID: PMC5384070 DOI: 10.1515/hukin-2017-0040] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The aim of the present study was to investigate lower limb anthropometric and composition variables related to running economy (RE) and running performance in a homogeneous group of high level European distance runners. RE at the speeds of 14, 16 and 18 km·h−1 (189 ± 12; 188 ± 11; 187 ± 11 O2 ml·kg−1·km−1) and maximal oxygen uptake (VO2max) (67.3 ± 2.9 ml·kg−1·min−1) of 13 high level distance runners were determined on a motorised treadmill. Anthropometric variables and body composition were measured. The BMI was related to RE at the speed of 14 (r2 = 0.434; p = 0.014), 16 (r2 = 0.436; p = 0.014) and 18 km·h−1 (r2 = 0.389; p = 0.023). Lower leg length was negatively related to RE at the speed of 16 and showed such a tendency at the speed of 14 and 18 km·h−1. VO2max indicated a moderate relationship with RE at the speeds of 14, 16 and 18 km·h−1 (r2 = 0.372, p = 0.030; r2 = 0.350, p = 0.033; r2 = 0.376, p = 0.026, respectively) which was confirmed by subsequent partial correlation analysis. While lower leg length and the BMI presented a relationship with RE, none of the calculated body composition and anthropometric proportions were related to RE or performance. The relationship between RE and VO2max would confirm the notion that RE could be at least partly compensated by VO2max to achieve high performance results.
Collapse
Affiliation(s)
- Rauno Laumets
- Faculty of Medicine, Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Karel Viigipuu
- Faculty of Medicine, Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Kerli Mooses
- Faculty of Medicine, Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Jarek Mäestu
- Faculty of Medicine, Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Priit Purge
- Faculty of Medicine, Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Ando Pehme
- Faculty of Medicine, Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Priit Kaasik
- Faculty of Medicine, Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| | - Martin Mooses
- Faculty of Medicine, Institute of Sport Sciences and Physiotherapy, University of Tartu, Tartu, Estonia
| |
Collapse
|
18
|
Constantini K, Wilhite DP, Chapman RF. A Clinician Guide to Altitude Training for Optimal Endurance Exercise Performance at Sea Level. High Alt Med Biol 2017; 18:93-101. [PMID: 28453305 DOI: 10.1089/ham.2017.0020] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Constantini, Keren, Daniel P. Wilhite, and Robert F. Chapman. A clinician guide to altitude training for optimal endurance exercise performance at sea level. High Alt Med Biol. 18:93-101, 2017.-For well over 50 years, endurance athletes have been utilizing altitude training in an effort to enhance performance in sea level competition. This brief review will offer the clinician a series of evidence-based best-practice guidelines on prealtitude and altitude training considerations, which can ultimately maximize performance improvement outcomes.
Collapse
Affiliation(s)
- Keren Constantini
- HH Morris Human Performance Laboratory, Department of Kinesiology, Indiana University , Bloomington, Indiana
| | - Daniel P Wilhite
- HH Morris Human Performance Laboratory, Department of Kinesiology, Indiana University , Bloomington, Indiana
| | - Robert F Chapman
- HH Morris Human Performance Laboratory, Department of Kinesiology, Indiana University , Bloomington, Indiana
| |
Collapse
|
19
|
Van Remoortel H, De Buck E, Compernolle V, Deldicque L, Vandekerckhove P. The effect of a standard whole blood donation on oxygen uptake and exercise capacity: a systematic review and meta-analysis. Transfusion 2016; 57:451-462. [DOI: 10.1111/trf.13893] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 09/02/2016] [Accepted: 09/08/2016] [Indexed: 11/30/2022]
Affiliation(s)
| | - Emmy De Buck
- Belgian Red Cross-Flanders; Mechelen Belgium
- Department of Public Health and Primary Care, Faculty of Medicine; KU Leuven; Belgium
| | - Veerle Compernolle
- Belgian Red Cross-Flanders; Mechelen Belgium
- Faculty of Medicine and Health Sciences; Ghent University; Ghent Belgium
| | - Louise Deldicque
- Exercise Physiology Research Group, Department of Kinesiology, FaBeR; KU Leuven; Belgium
- Institute of Neuroscience; Université Catholique de Louvain; Louvain-la-Neuve Belgium
| | - Philippe Vandekerckhove
- Belgian Red Cross-Flanders; Mechelen Belgium
- Department of Public Health and Primary Care, Faculty of Medicine; KU Leuven; Belgium
- Faculty of Medicine and Health Sciences; Ghent University; Ghent Belgium
| |
Collapse
|
20
|
Bădău D, Bacârea A, Ungur RN, Bădău A, Martoma AM. Biochemical and functional modifications in biathlon athletes at medium altitude training / Modificările biochimice și funcționale ale atleților biatloniști după antrenament la altitudine medie. REV ROMANA MED LAB 2016. [DOI: 10.1515/rrlm-2016-0008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Objective: The aim of our research was to identify physiological and biochemical changes induced by training at medium altitude.
Methods: Ten biathlon athletes underwent 28-day training camp at medium altitude in order to improve their aerobic effort, following the living high-base train high-interval train low (Hi-Hi-Lo) protocol. There were investigated three categories of functional and biochemical parameters, targeting the hematological changes (RBC, HCT, HGB), the oxidative (lipoperoxid, free malondialdehyde and total malondialdehyde) and antioxidative balance (the hydrogen donor capacity, ceruloplasmin and uric acid) and the capacity of effort (the maximum aerobic power, the cardiovascular economy in effort, the maximum O2 consumption).
Results: All the biochemical and functional evaluated parameters showed significant increases between the pre-training testing and post-training testing (5.13 ± 0.11 vs. 6.50 ± 0.09, p < 0.0001 for RBC; 44.80 ± 1.22 vs. 51.31 ± 2.31, p < 0.0001 for HCT; 15.06 ± 0.33 vs. 17.14 ± 0.25, p < 0.0001 for HGB; 1.32 ± 0.04 vs.1.62 ± 0.01, p < 0.0001 for LPx; 1.61 ± 0.01 vs. 1.73 ± 0.01, p < 0.0001 for free MDA; 2.98 ± 0.08 vs. 3.37 ± 0.03, p < 0.0001 for total MDA; 45.92 ± 0.13 vs. 57.98 ± 0.12, p < 0.0001 for HD; 25.95 ± 0.13 vs. 31.04 ± 0.06, p < 0.0001 for Crp; 3.47 ± 0.03 vs.7.69 ± 0.02, p < 0.0001 for UA; 63.91 ± 1.00 vs. 81.53 ± 1.97, p < 0.0001 for MAP; 33.13 ± 0.57 vs. 57.41 ± 0.63, p < 0.0001 for CVEE; 4190 ± 50.45 vs. 5945 ± 46.48, p < 0.0001 for VO2max).
Conclusions: Aerobic effort capacity of biathlon athletes has increased in the post-training period, using Hi-Hi-Lo protocol.
Collapse
Affiliation(s)
- Dana Bădău
- Department of Human Movement Sciences, University of Medicine and Pharmacy Tîrgu Mures, Romania
| | - Anca Bacârea
- Department of Pathophysiology, Univeristy of Medicine and Pharmacy Tîrgu Mureș, Str. Gh. Marinescu, Nr. 5, Tîrgu Mureș, Romania
| | - Ramona Natalia Ungur
- Department of Physical Education, University of Medicine and Pharmacy Tîrgu Mures, Romania
| | - Adela Bădău
- Department of Physical Education, University of Medicine and Pharmacy Tîrgu Mures, Romania
| | - Alina Mirela Martoma
- Department of Physical Education and Special Motricity, Transilvania University of Brasov, Romania
| |
Collapse
|
21
|
Abstract
Today the Kenyan dominance in middle- and long-distance running is so profound that it has no equivalence to any other sport in the world. Critical physiological factors for performance in running include maximal oxygen consumption (VO2max), fractional VO2max utilization and running economy (energetic cost of running). Kenyan and non-Kenyan elite runners seem to be able to reach very high, but similar maximal oxygen uptake levels just as there is some indication that untrained Kenyans and non-Kenyans have a similar VO2max. In addition, the fractional utilization of VO2max seems to be very high but similar in Kenyan and European runners. Similarly, no differences in the proportion of slow muscle fibers have been observed when comparing Kenyan elite runners with their Caucasian counterparts. In contrast, the oxygen cost of running at a given running velocity has been found to be lower in Kenyan elite runners relative to other elite runners and there is some indication that this is due to differences in body dimensions. Pulmonary system limitations have been observed in Kenyan runners in the form of exercise-induced arterial hypoxemia, expiratory flow limitation, and high levels of respiratory muscle work. It appears that Kenyan runners do not possess a pulmonary system that confers a physiological advantage. Additional studies on truly elite Kenyan runners are necessary to understand the underlying physiology which permits extraordinary running performances.
Collapse
Affiliation(s)
- H B Larsen
- The Copenhagen Muscle Research Centre, Rigshospitalet, Copenhagen, Denmark
| | - A W Sheel
- School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
| |
Collapse
|
22
|
Karlsen T, Leinan IM, Aamot IL, Dalen H, Støylen A. Safety of the CO-Rebreathing Method in Patients with Coronary Artery Disease. Med Sci Sports Exerc 2016; 48:33-8. [PMID: 26672919 DOI: 10.1249/mss.0000000000000729] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE To address and study the safety concerns with the improved carbon monoxide (CO) rebreathing method for measuring total blood volume in patients with coronary artery disease to implement the use of the methodology in this patient group. METHODS Eighteen patients with stable coronary artery disease (age 62 ± 7 yr, 24 ± 5 months since diagnosis) were investigated using the improved CO-rebreathing test. Before, during, and up to 2 h after the test, ECG, blood pressure, arterial oxygen saturation, carbon monoxide bound to hemoglobin (HbCO%), and cardiac function were measured. At 24 h, HbCO% and troponin-T were measured. DESIGN Cross-over. RESULTS Six minutes after the CO-rebreathing test, HbCO increased from 1.5% ± 0.4% to 6.0% ± 0.6%, with a subsequent decrease to 4.5% ± 0.4% and 1.4% ± 0.4% at 2 h and 24 h after the test, respectively. Resting heart rate, stroke volume, cardiac output, and ejection fraction were 64 ± 11 bpm, 93.9 ± 16.5 mL per beat, 5.84 ± 0.99 L, and 48.5% ± 5.7% and remained unchanged during and 10 min after the rebreathing. All patients were in sinus rhythm during the 2-h observation period, without ST- or T-wave changes, with low numbers of premature beats and normal rate variability. Systolic and diastolic blood pressure gradually decreased during the observation period. Troponin-T was below the 99th percentile for all the participants 24 h after the test. CONCLUSION Cardiovascular function and safety indices remained unchanged after exposure to approximately 6% HbCO, indicating that the method is safe to perform in patients with stable coronary artery disease.
Collapse
Affiliation(s)
- Trine Karlsen
- 1K.G. Jebsen Center of Exercise in Medicine, Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, NORWAY; 2Department of Cardiology, St. Olav's University Hospital, NORWAY; 3Clinical Services, St. Olav's University Hospital, NORWAY; 4Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Norway; and 5Levanger Hospital, Nord-Trøndelag Health Trust, Levanger, NORWAY
| | | | | | | | | |
Collapse
|
23
|
Zieliński J, Kusy K. Hypoxanthine: A Universal Metabolic Indicator of Training Status in Competitive Sports. Exerc Sport Sci Rev 2016. [PMID: 26196868 DOI: 10.1249/jes.0000000000000055] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cardiorespiratory and biochemical indicators typically used by contemporary elite athletes seem to have limited applicability. According to some recent studies, purine metabolism better reflects exercise response and muscle adaptation in this group. We propose using purine derivatives, especially plasma hypoxanthine concentration, as indicators of training status in consecutive training phases in highly trained athletes.
Collapse
Affiliation(s)
- Jacek Zieliński
- Department of Athletics, Faculty of Physical Education, Sport and Rehabilitation, Poznan University of Physical Education, Poznań, Poland
| | | |
Collapse
|
24
|
Turner G, Gibson OR, Watt PW, Pringle JSM, Richardson AJ, Maxwell NS. The time course of endogenous erythropoietin, IL-6, and TNFα in response to acute hypoxic exposures. Scand J Med Sci Sports 2016; 27:714-723. [DOI: 10.1111/sms.12700] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2016] [Indexed: 12/13/2022]
Affiliation(s)
- G. Turner
- Environmental Extremes Laboratory; Centre for Sport and Exercise Science and Medicine (SESAME); University of Brighton; Eastbourne UK
- English Institute of Sport; EIS Performance Centre; Loughborough University; Loughborough UK
| | - O. R. Gibson
- Environmental Extremes Laboratory; Centre for Sport and Exercise Science and Medicine (SESAME); University of Brighton; Eastbourne UK
| | - P. W. Watt
- Environmental Extremes Laboratory; Centre for Sport and Exercise Science and Medicine (SESAME); University of Brighton; Eastbourne UK
| | - J. S. M. Pringle
- English Institute of Sport; EIS Performance Centre; Loughborough University; Loughborough UK
| | - A. J. Richardson
- Environmental Extremes Laboratory; Centre for Sport and Exercise Science and Medicine (SESAME); University of Brighton; Eastbourne UK
| | - N. S. Maxwell
- Environmental Extremes Laboratory; Centre for Sport and Exercise Science and Medicine (SESAME); University of Brighton; Eastbourne UK
| |
Collapse
|
25
|
Ryan BJ, Goodrich JA, Schmidt WF, Stothard ER, Wright KP, Byrnes WC. Haemoglobin mass alterations in healthy humans following four-day head-down tilt bed rest. Exp Physiol 2016; 101:628-40. [PMID: 26914389 PMCID: PMC4851582 DOI: 10.1113/ep085665] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 02/19/2016] [Indexed: 02/01/2023]
Abstract
NEW FINDINGS What is the central question of this study? Is haemoglobin mass (Hbmass) decreased following 4 days of head-down tilt bed rest (HDTBR), and does increased red blood cell (RBC) destruction mediate this adaptation? What is the main finding and its importance? Haemoglobin mass was increased immediately following HDTBR, before decreasing below baseline 5 days after return to normal living conditions. The transient increase in Hbmass might be the result of decreased RBC destruction, but it is also possible that spleen contraction after HDTBR contributed to this adaptation. Our data suggest that the decreased Hbmass 5 days following HDTBR resulted from decreased RBC production, not increased RBC destruction. Rapid decreases in haemoglobin mass (Hbmass) have been reported in healthy humans following spaceflight and descent from high altitude. It has been proposed that a selective increase in the destruction of young red blood cells (RBCs) mediates these decreases, but conclusive evidence demonstrating neocytolysis in humans is lacking. Based on the proposed triggers and time course of adaptation during spaceflight, we hypothesized that Hbmass would be reduced after 4 days of -6 deg head-down tilt bed rest (HDTBR) and that this would be associated with evidence for increased RBC destruction. We assessed Hbmass in seven healthy, recreationally active men before (PRE), 5 h after (POST) and 5 days after (POST5) 4 days of HDTBR. The concentration of erythropoietin decreased from 7.1 ± 1.8 mIU ml(-1) at PRE to 5.2 ± 2.8 mIU ml(-1) at POST (mean ± SD; P = 0.028). Contrary to our hypothesis, Hbmass was increased from 817 ± 135 g at PRE to 849 ± 141 g at POST (P = 0.014) before decreasing below PRE to 789 ± 139 g at POST5 (P = 0.027). From PRE to POST, the concentration of haptoglobin increased from 0.54 ± 0.32 to 0.68 ± 0.28 g l(-1) (P = 0.013) and the concentration of bilirubin decreased from 0.50 ± 0.24 to 0.32 ± 0.11 mg dl(-1) (P = 0.054), suggesting that decreased RBC destruction might have contributed to the increased Hbmass. However, it is possible that spleen contraction following HDTBR also played a role in the increase in Hbmass at POST, but as the transient increase in Hbmass was unexpected, we did not collect data that would provide direct evidence for or against spleen contraction. From PRE to POST5, the concentration of soluble transferrin receptor decreased from 20.7 ± 3.9 to 17.1 ± 3.3 nmol l(-1) (P = 0.018) but the concentrations of ferritin, haptoglobin and bilirubin were not significantly altered, suggesting that the decrease in Hbmass was mediated by decreased RBC production rather than increased RBC destruction. Peak oxygen uptake decreased by 0.31 ± 0.16 l min(-1) from PRE to POST (P = 2 × 10(-4) ) but was not significantly altered at POST5 compared with PRE. Overall, these findings indicate that 4 days of HDTBR does not increase RBC destruction and that re-examination of the time course and mechanisms of Hbmass alterations following short-term spaceflight and simulated microgravity is warranted.
Collapse
Affiliation(s)
- Benjamin J. Ryan
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Jesse A. Goodrich
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Walter F. Schmidt
- Department of Sports Medicine/Sports Physiology, University of Bayreuth, Bayreuth, Germany
| | - Ellen R. Stothard
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Kenneth P. Wright
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - William C. Byrnes
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| |
Collapse
|
26
|
Knechtle B, Nikolaidis PT, Onywera VO, Zingg MA, Rosemann T, Rüst CA. Male and female Ethiopian and Kenyan runners are the fastest and the youngest in both half and full marathon. SPRINGERPLUS 2016; 5:223. [PMID: 27026917 PMCID: PMC4771648 DOI: 10.1186/s40064-016-1915-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 02/17/2016] [Indexed: 11/10/2022]
Abstract
In major marathon races such as the 'World Marathon Majors', female and male East African runners particularly from Ethiopia and Kenya are the fastest. However, whether this trend appears for female and male Ethiopians and Kenyans at recreational level runners (i.e. races at national level) and in shorter road races (e.g. in half-marathon races) has not been studied yet. Thus, the aim of the present study was to examine differences in the performance and the age of female and male runners from East Africa (i.e. Ethiopians and Kenyans) between half- and full marathons. Data from 508,108 athletes (125,894 female and 328,430 male half-marathoners and 10,205 female and 43,489 male marathoners) originating from 126 countries and competing between 1999 and 2014 in all road-based half-marathons and marathons held in one country (Switzerland) were analysed using Chi square (χ(2)) tests, mixed-effects regression analyses and one-way analyses of variance. In half-marathons, 48 women (0.038 %) and 63 men (0.019 %) were from Ethiopia and 80 women (0.063 %) and 134 men (0.040 %) from Kenya. In marathons, three women (0.029 %) and 15 men (0.034 %) were from Ethiopia and two women (0.019 %) and 33 men (0.075 %) from Kenya. There was no statistically significant association between the nationality of East Africans and the format of a race. In both women and men, the fastest race times in half-marathons and marathons were achieved by East African runners (p < 0.001). Ethiopian and Kenyan runners were the youngest in both sexes and formats of race (p < 0.001). In summary, women and men from Ethiopia and Kenya, despite they accounted for <0.1 % in half-marathons and marathons, achieved the fastest race times and were the youngest in both half-marathons and marathons. These findings confirmed in the case of half-marathon the trend previously observed in marathon races for a better performance and a younger age in East African runners from Ethiopia and Kenya.
Collapse
Affiliation(s)
- Beat Knechtle
- Facharzt FMH für Allgemeinmedizin, Gesundheitszentrum St. Gallen, Vadianstrasse 26, St. Gallen, 9001 Switzerland ; Institute of Primary Care, University of Zurich, Zurich, Switzerland
| | - Pantelis T Nikolaidis
- Department of Physical and Cultural Education, Hellenic Army Academy, Athens, Greece
| | - Vincent O Onywera
- Department of Recreation Management and Exercise Science, Kenyatta University, Nairobi, Kenya
| | - Matthias A Zingg
- Institute of Primary Care, University of Zurich, Zurich, Switzerland
| | - Thomas Rosemann
- Institute of Primary Care, University of Zurich, Zurich, Switzerland
| | - Christoph A Rüst
- Institute of Primary Care, University of Zurich, Zurich, Switzerland
| |
Collapse
|
27
|
Foster GE, Koehle MS, Dominelli PB, Mwangi FM, Onywera VO, Boit MK, Tremblay JC, Boit C, Sheel AW. Pulmonary mechanics and gas exchange during exercise in Kenyan distance runners. Med Sci Sports Exerc 2015; 46:702-10. [PMID: 24042305 DOI: 10.1249/mss.0000000000000161] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE The purpose of this study was to determine arterial blood gases, the mechanical limits for generating expiratory flow and the work performed by the respiratory muscles during treadmill exercise in Kenyan runners. METHODS Kenyan runners (10 men and 4 women; mean ± SD age = 25.2 ± 1.3 yr) were instrumented with a radial artery catheter, an esophageal balloon-tipped catheter, and an esophageal temperature probe for the determination of blood gases, the work of breathing and core temperature, respectively. Testing occurred at 1545 m above sea level. RESULTS There were significant decreases in the arterial partial pressure of O2 and oxyhemoglobin saturation and a widening of the alveolar-to-arterial difference in O2 from rest to peak exercise. The mechanical work of breathing increased with increasing minute ventilation and was commensurate with values expected for treadmill running in elite athletes. During heavy exercise, significant expiratory flow limitation was present in half of the subjects while the remaining subjects demonstrated impending flow limitation. CONCLUSIONS Pulmonary system limitations were present in Kenyan runners in the form of exercise-induced arterial hypoxemia, expiratory flow limitation, and high levels of respiratory muscle work. It appears that Kenyan runners do not possess a pulmonary system that confers a physiological advantage.
Collapse
Affiliation(s)
- Glen E Foster
- 1School of Kinesiology, University of British Columbia, Vancouver, BC, CANADA; 2Division of Sports Medicine, University of British Columbia, Vancouver, BC, CANADA; 3Department of Recreation Management and Exercise Science, Kenyatta University, Nairobi, KENYA; and 4Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, CANADA
| | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Saugy JJ, Schmitt L, Cejuela R, Faiss R, Hauser A, Wehrlin JP, Rudaz B, Delessert A, Robinson N, Millet GP. Comparison of "Live High-Train Low" in normobaric versus hypobaric hypoxia. PLoS One 2014; 9:e114418. [PMID: 25517507 PMCID: PMC4269399 DOI: 10.1371/journal.pone.0114418] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Accepted: 11/10/2014] [Indexed: 11/18/2022] Open
Abstract
We investigated the changes in both performance and selected physiological parameters following a Live High-Train Low (LHTL) altitude camp in either normobaric hypoxia (NH) or hypobaric hypoxia (HH) replicating current "real" practices of endurance athletes. Well-trained triathletes were split into two groups (NH, n = 14 and HH, n = 13) and completed an 18-d LHTL camp during which they trained at 1100-1200 m and resided at an altitude of 2250 m (PiO2 = 121.7±1.2 vs. 121.4±0.9 mmHg) under either NH (hypoxic chamber; FiO2 15.8±0.8%) or HH (real altitude; barometric pressure 580±23 mmHg) conditions. Oxygen saturations (SpO2) were recorded continuously daily overnight. PiO2 and training loads were matched daily. Before (Pre-) and 1 day after (Post-) LHTL, blood samples, VO2max, and total haemoglobin mass (Hb(mass)) were measured. A 3-km running test was performed near sea level twice before, and 1, 7, and 21 days following LHTL. During LHTL, hypoxic exposure was lower for the NH group than for the HH group (220 vs. 300 h; P<0.001). Night SpO2 was higher (92.1±0.3 vs. 90.9±0.3%, P<0.001), and breathing frequency was lower in the NH group compared with the HH group (13.9±2.1 vs. 15.5±1.5 breath.min(-1), P<0.05). Immediately following LHTL, similar increases in VO2max (6.1±6.8 vs. 5.2±4.8%) and Hb(mass) (2.6±1.9 vs. 3.4±2.1%) were observed in NH and HH groups, respectively, while 3-km performance was not improved. However, 21 days following the LHTL intervention, 3-km run time was significantly faster in the HH (3.3±3.6%; P<0.05) versus the NH (1.2±2.9%; ns) group. In conclusion, the greater degree of race performance enhancement by day 21 after an 18-d LHTL camp in the HH group was likely induced by a larger hypoxic dose. However, one cannot rule out other factors including differences in sleeping desaturations and breathing patterns, thus suggesting higher hypoxic stimuli in the HH group.
Collapse
Affiliation(s)
- Jonas J. Saugy
- ISSUL, Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
- Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Laurent Schmitt
- National School of Mountain Sports/National Ski-Nordic Centre, Prémanon, France
| | - Roberto Cejuela
- Departmental Section of Physical Education and Sports, University of Alicante, Alicante, Spain
| | - Raphael Faiss
- ISSUL, Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
- Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Anna Hauser
- ISSUL, Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
- Swiss Federal Institute of Sport, Magglingen, Switzerland
| | - Jon P. Wehrlin
- Swiss Federal Institute of Sport, Magglingen, Switzerland
| | - Benjamin Rudaz
- ISSUL, Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Audric Delessert
- ISSUL, Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Neil Robinson
- Swiss Laboratory for Doping Analyses, University of Lausanne, Lausanne, Switzerland
| | - Grégoire P. Millet
- ISSUL, Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
- Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
- * E-mail:
| |
Collapse
|
29
|
Cheung SS, Mutanen NE, Karinen HM, Koponen AS, Kyröläinen H, Tikkanen HO, Peltonen JE. Ventilatory chemosensitivity, cerebral and muscle oxygenation, and total hemoglobin mass before and after a 72-day mt. Everest expedition. High Alt Med Biol 2014; 15:331-40. [PMID: 25211648 DOI: 10.1089/ham.2013.1153] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND We investigated the effects of chronic hypobaric hypoxic acclimatization, performed over the course of a 72-day self-supported Everest expedition, on ventilatory chemosensitivity, arterial saturation, and tissue oxygenation adaptation along with total hemoglobin mass (tHb-mass) in nine experienced climbers (age 37±6 years, [Formula: see text] 55±7 mL·kg(-1)·min(-1)). METHODS Exercise-hypoxia tolerance was tested using a constant treadmill exercise of 5.5 km·h(-1) at 3.8% grade (mimicking exertion at altitude) with 3-min steps of progressive normobaric poikilocapnic hypoxia. Breath-by-breath ventilatory responses, Spo2, and cerebral (frontal cortex) and active muscle (vastus lateralis) oxygenation were measured throughout. Acute hypoxic ventilatory response (AHVR) was determined by linear regression slope of ventilation vs. Spo2. PRE and POST (<15 days) expedition, tHb-mass was measured using carbon monoxide-rebreathing. RESULTS Post-expedition, exercise-hypoxia tolerance improved (11:32±3:57 to 16:30±2:09 min, p<0.01). AHVR was elevated (1.25±0.33 to 1.63±0.38 L·min(-1.)%(-1) Spo2, p<0.05). Spo2 decreased throughout exercise-hypoxia in both trials, but was preserved at higher values at 4800 m post-expedition. Cerebral oxygenation decreased progressively with increasing exercise-hypoxia in both trials, with a lower level of deoxyhemoglobin POST at 2400, 3500 and 4800 m. Muscle oxygenation also decreased throughout exercise-hypoxia, with similar patterns PRE and POST. No relationship was observed between the slope of AHVR and cerebral or muscle oxygenation either PRE or POST. Absolute tHb-mass response exhibited great individual variation with a nonsignificant 5.4% increasing trend post-expedition (975±154 g PRE and 1025±124 g POST, p=0.17). CONCLUSIONS We conclude that adaptation to chronic hypoxia during a climbing expedition to Mt. Everest will increase hypoxic tolerance, AHVR, and cerebral but not muscle oxygenation, as measured during simulated acute hypoxia at sea level. However, tHb-mass did not increase significantly and improvement in cerebral oxygenation was not associated with the change in AHVR.
Collapse
Affiliation(s)
- Stephen S Cheung
- 1 Environmental Ergonomics Laboratory, Department of Kinesiology, Brock University , St. Catharines, Ontario, Canada
| | | | | | | | | | | | | |
Collapse
|
30
|
Wachsmuth N, Kley M, Spielvogel H, Aughey RJ, Gore CJ, Bourdon PC, Hammond K, Sargent C, Roach GD, Sanchez RS, Claros JCJ, Schmidt WF, Garvican-Lewis LA. Changes in blood gas transport of altitude native soccer players near sea-level and sea-level native soccer players at altitude (ISA3600). Br J Sports Med 2014; 47 Suppl 1:i93-9. [PMID: 24282216 PMCID: PMC3903154 DOI: 10.1136/bjsports-2013-092761] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Objectives The optimal strategy for soccer teams playing at altitude is not known, that is, ‘fly-in, fly-out’ versus short-term acclimatisation. Here, we document changes in blood gas and vascular volumes of sea-level (Australian, n=20) and altitude (Bolivian, n=19) native soccer players at 3600 m. Methods Haemoglobin-oxygen saturation (Hb-sO2), arterial oxygen content (CaO2), haemoglobin mass (Hbmass), blood volume (BV) and blood gas concentrations were measured before descent (Bolivians only), together with aerobic fitness (via Yo-YoIR1), near sea-level, after ascent and during 13 days at 3600 m. Results At baseline, haemoglobin concentration [Hb] and Hbmass were higher in Bolivians (mean±SD; 18.2±1.0 g/dL, 12.8±0.8 g/kg) than Australians (15.0±0.9 g/dL, 11.6±0.7 g/kg; both p≤0.001). Near sea-level, [Hb] of Bolivians decreased to 16.6±0.9 g/dL, but normalised upon return to 3600 m; Hbmass was constant regardless of altitude. In Australians, [Hb] increased after 12 days at 3600 m to 17.3±1.0 g/dL; Hbmass increased by 3.0±2.7% (p≤0.01). BV decreased in both teams at altitude by ∼400 mL. Arterial partial pressure for oxygen (PaO2), Hb-sO2 and CaO2 of both teams decreased within 2 h of arrival at 3600 m (p≤0.001) but increased over the following days, with CaO2 overcompensated in Australians (+1.7±1.2 mL/100 mL; p≤0.001). Yo-YoIR1 was lower on the 3rd versus 10th day at altitude and was significantly related to CaO2. Conclusions The marked drop in PaO2 and CaO2 observed after ascent does not support the ‘fly-in, fly-out’ approach for soccer teams to play immediately after arrival at altitude. Although short-term acclimatisation was sufficient for Australians to stabilise their CaO2 (mostly due to loss of plasma volume), 12 days appears insufficient to reach chronic levels of adaption.
Collapse
Affiliation(s)
- Nadine Wachsmuth
- Department of Sports Medicine/Sports Physiology, University of Bayreuth, , Bayreuth, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Mooses M, Mooses K, Haile DW, Durussel J, Kaasik P, Pitsiladis YP. Dissociation between running economy and running performance in elite Kenyan distance runners. J Sports Sci 2014; 33:136-44. [DOI: 10.1080/02640414.2014.926384] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
32
|
Chapman RF, Laymon Stickford AS, Lundby C, Levine BD. Timing of return from altitude training for optimal sea level performance. J Appl Physiol (1985) 2014; 116:837-43. [DOI: 10.1152/japplphysiol.00663.2013] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
While a number of published studies exist to guide endurance athletes with the best practices regarding implementation of altitude training, a key unanswered question concerns the proper timing of return to sea level prior to major competitions. Evidence reviewed here suggests that, altogether, the deacclimatization responses of hematological, ventilatory, and biomechanical factors with return to sea level likely interact to determine the best timing for competitive performance.
Collapse
Affiliation(s)
- Robert F. Chapman
- Human Performance Laboratory, Department of Kinesiology, Indiana University, Bloomington, Indiana
| | | | - Carsten Lundby
- Center for Integrative Human Physiology, Institute of Physiology, University of Zurich, Switzerland; and
| | - Benjamin D. Levine
- Institute for Exercise and Environmental Medicine, Presbyterian Hospital of Dallas and University of Texas Southwest Medical Center, Dallas, Texas
| |
Collapse
|
33
|
Application of the optimized CO-rebreathing method for determination of hemoglobin mass in patients with polycythemia vera. Ann Hematol 2014; 93:1159-65. [PMID: 24488226 DOI: 10.1007/s00277-014-2020-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 01/21/2014] [Indexed: 10/25/2022]
Abstract
Determination of red cell volume (RCV) might contribute to establishing the diagnosis of polycythemia vera (PV). A novel simplified method to detect RCV through CO rebreathing is nowadays applied in healthy young individuals but was not tested in a clinical or PV setting. The aim of the present study is to evaluate whether this spirometric approach is applicable in older subjects and contributes to PV diagnosis in a proof-of-concept approach. At first, RCV was determined by the optimized CO-rebreathing method in healthy subjects >50 years of age (n = 81, age 66 ± 9 years). Failure rate and age distribution of subjects who failed with CO rebreathing were analyzed. Then, RCV was measured in male PV patients (n = 7) and compared to healthy male controls (n = 35). RCV values in relation to several anthropometric references (body weight, body surface area (BSA), lean body mass (LBM)) were calculated to determine the sensitivity and specificity of established RCV thresholds when using optimized CO rebreathing. In healthy subjects, test failure rate was 9.9 %, but failure was not associated with age. Sensitivity and specificity (sens/spec) to detect PV was 100 %/83 % using the criteria of the PV study group. Using criteria based on BSA, sens/spec was 14 %/100 %. An arbitrary threshold of 50 ml/kg LBM yielded sens/spec of 100 %/97 %. In conclusion, this proof-of-concept indicates that optimized CO rebreathing is applicable in older subjects and allows determining RCV for the diagnosis of PV. Normalized values for RCV measures obtained from CO rebreathing are needed to grant sufficient sensitivity and/or specificity.
Collapse
|
34
|
Abstract
The dominance of East African distance runners and sprinters of West African origin invites discussion around the contribution of genetic and lifestyle factors to performance. In this review, we focus on the genetic basis for performance. Previous research associating candidate genes such as ACE and ACTN3 to endurance and sprint performance in Caucasian populations has not been replicated in African populations. This may be influenced by numerous factors, including small sample sizes, comparisons across different ethnic populations and problems identifying appropriate control groups. Conceptually, these failures reveal the complex polygenic nature of physiology and performance, and the erroneous application of a candidate gene approach to more genetically diverse African populations. We argue that research has in fact established a role for genes in performance, and that the frequency, rather than the prevalence, of favourable genetic variants within certain populations may account for the performance dominance in these populations.
Collapse
Affiliation(s)
- Ross Tucker
- UCT/MRC Research Unit for Exercise Science and Sports Medicine, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
| | | | | |
Collapse
|
35
|
Gore CJ, Sharpe K, Garvican-Lewis LA, Saunders PU, Humberstone CE, Robertson EY, Wachsmuth NB, Clark SA, McLean BD, Friedmann-Bette B, Neya M, Pottgiesser T, Schumacher YO, Schmidt WF. Altitude training and haemoglobin mass from the optimised carbon monoxide rebreathing method determined by a meta-analysis. Br J Sports Med 2013; 47 Suppl 1:i31-9. [PMID: 24282204 PMCID: PMC3903147 DOI: 10.1136/bjsports-2013-092840] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/21/2013] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To characterise the time course of changes in haemoglobin mass (Hbmass) in response to altitude exposure. METHODS This meta-analysis uses raw data from 17 studies that used carbon monoxide rebreathing to determine Hbmass prealtitude, during altitude and postaltitude. Seven studies were classic altitude training, eight were live high train low (LHTL) and two mixed classic and LHTL. Separate linear-mixed models were fitted to the data from the 17 studies and the resultant estimates of the effects of altitude used in a random effects meta-analysis to obtain an overall estimate of the effect of altitude, with separate analyses during altitude and postaltitude. In addition, within-subject differences from the prealtitude phase for altitude participant and all the data on control participants were used to estimate the analytical SD. The 'true' between-subject response to altitude was estimated from the within-subject differences on altitude participants, between the prealtitude and during-altitude phases, together with the estimated analytical SD. RESULTS During-altitude Hbmass was estimated to increase by ∼1.1%/100 h for LHTL and classic altitude. Postaltitude Hbmass was estimated to be 3.3% higher than prealtitude values for up to 20 days. The within-subject SD was constant at ∼2% for up to 7 days between observations, indicative of analytical error. A 95% prediction interval for the 'true' response of an athlete exposed to 300 h of altitude was estimated to be 1.1-6%. CONCLUSIONS Camps as short as 2 weeks of classic and LHTL altitude will quite likely increase Hbmass and most athletes can expect benefit.
Collapse
Affiliation(s)
- Christopher J Gore
- Department of Physiology, Australian Institute of Sport, Canberra, Australia
- Exercise Physiology Laboratory, Flinders University, Adelaide, Australia
- University of Canberra, Canberra, Australia
| | - Ken Sharpe
- Department of Mathematics and Statistics, The University of Melbourne, Melbourne, Australia
| | - Laura A Garvican-Lewis
- Department of Physiology, Australian Institute of Sport, Canberra, Australia
- University of Canberra, Canberra, Australia
| | - Philo U Saunders
- Department of Physiology, Australian Institute of Sport, Canberra, Australia
- University of Canberra, Canberra, Australia
| | - Clare E Humberstone
- Department of Physiology, Australian Institute of Sport, Canberra, Australia
| | | | - Nadine B Wachsmuth
- Department of Sports Medicine/Sports Physiology, University of Bayreuth, Bayreuth, Germany
| | - Sally A Clark
- Department of Physiology, Australian Institute of Sport, Canberra, Australia
| | - Blake D McLean
- School of Exercise Science, Australian Catholic University, Melbourne, Australia
| | | | - Mitsuo Neya
- Singapore Sports Institute, Singapore Sports Council, Singapore, Singapore
| | | | | | - Walter F Schmidt
- Department of Sports Medicine/Sports Physiology, University of Bayreuth, Bayreuth, Germany
| |
Collapse
|
36
|
Malczewska-Lenczowska J, Sitkowski D, Orysiak J, Pokrywka A, Szygula Z. Total haemoglobin mass, blood volume and morphological indices among athletes from different sport disciplines. Arch Med Sci 2013; 9:780-7. [PMID: 24273557 PMCID: PMC3832821 DOI: 10.5114/aoms.2013.36926] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 02/20/2013] [Accepted: 02/20/2013] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION Haemoglobin is a key determinant of maximal oxygen uptake. This study's objective was to assess total haemoglobin mass (tHb-mass), as well as blood volume and morphological indices in athletes training different sports disciplines. MATERIAL AND METHODS This study was conducted on 176 endurance and non-endurance athletes (males and females). tHb-mass, blood volume (BV), plasma volume (PV), and red cell volume (RCV) were determined by optimized carbon monoxide rebreathing method. Haemoglobin concentration (Hb), haematocrit (Hct), red blood count (RBC) were also determined. RESULTS In endurance sports, gender regardless, no significant differences in relative mean values of tHb-mass (12.8-13.1 g/kg - males; 10.4-10.6 g/kg - females), BV (90.8-94.0 ml/kg - males; 82.7-86.9 ml/kg - females), RCV (36.6-38.0 ml/kg - males; 31.1-31.5 ml/kg - females) or of PV in males (54.2-56.4 ml/kg) were observed. The above indices' relative values, gender regardless, were significantly lower in judo (11.2 ±0.7 g/kg, 81.8 ±5.9 ml/kg, 48.6 ±4.5 ml/kg and 33.1 ±2.0 ml/kg - males; 9.3 ±0.7 g/kg, 74.3 ±5.6 ml/kg, 46.4 ±4.0 ml/kg and 27.9 ±2.1 ml/kg - females) compared to endurance sports (p < 0.001). No substantial differences were observed in morphological blood indices in males, whereas this differentiation was found between certain sports in female athletes. CONCLUSIONS The lack of differences in tHb-mass, BV, PV and RCV in endurance sports and presence of this differentiation between various sports shows that the types of training might affect levels of mentioned indices. Measurements of tHb-mass and BV parameters prove Hb, Hct and RBC to have limited value for haematological status evaluations.
Collapse
Affiliation(s)
| | | | - Joanna Orysiak
- Department of Nutrition Physiology, Institute of Sport, Warsaw, Poland
| | - Andrzej Pokrywka
- Department of Anti-Doping Research, Institute of Sport, Warsaw, Poland
| | - Zbigniew Szygula
- Department of Sports Medicine, University School of Physical Education, Cracow, Poland
- University of Social Sciences, Lodz, Poland
| |
Collapse
|
37
|
Harm C, Knechtle B, Rüst CA, Rosemann T, Lepers R, Onywera V. Performance of Kenyan athletes in mountain versus flat marathon running - An example in Switzerland. JOURNAL OF HUMAN SPORT AND EXERCISE 2013. [DOI: 10.4100/jhse.2013.84.01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|
38
|
Wachsmuth NB, Völzke C, Prommer N, Schmidt-Trucksäss A, Frese F, Spahl O, Eastwood A, Stray-Gundersen J, Schmidt W. The effects of classic altitude training on hemoglobin mass in swimmers. Eur J Appl Physiol 2012; 113:1199-211. [PMID: 23138148 DOI: 10.1007/s00421-012-2536-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Accepted: 10/20/2012] [Indexed: 10/27/2022]
Abstract
Aim of the study was to determine the influence of classic altitude training on hemoglobin mass (Hb-mass) in elite swimmers under the following aspects: (1) normal oscillation of Hb-mass at sea level; (2) time course of adaptation and de-adaptation; (3) sex influences; (4) influences of illness and injury; (5) interaction of Hb-mass and competition performance. Hb-mass of 45 top swimmers (male 24; female 21) was repeatedly measured (~6 times) over the course of 2 years using the optimized CO-rebreathing method. Twenty-five athletes trained between one and three times for 3-4 weeks at altitude training camps (ATCs) at 2,320 m (3 ATCs) and 1,360 m (1 ATC). Performance was determined by analyzing 726 competitions according to the German point system. The variation of Hb-mass without hypoxic influence was 3.0 % (m) and 2.7 % (f). At altitude, Hb-mass increased by 7.2 ± 3.3 % (p < 0.001; 2,320 m) and by 3.8 ± 3.4 % (p < 0.05; 1,360 m). The response at 2,320 m was not sex-related, and no increase was found in ill and injured athletes (n = 8). Hb-mass was found increased on day 13 and was still elevated 24 days after return (4.0 ± 2.7 %, p < 0.05). Hb-mass had only a small positive effect on swimming performance; an increase in performance was only observed 25-35 days after return from altitude. In conclusion, the altitude (2,320 m) effect on Hb-mass is still present 3 weeks after return, it decisively depends on the health status, but is not influenced by sex. In healthy subjects it exceeds by far the oscillation occurring at sea level. After return from altitude performance increases after a delay of 3 weeks.
Collapse
Affiliation(s)
- N B Wachsmuth
- Department of Sports Medicine/Sports Physiology, University of Bayreuth, 95440 Bayreuth, Germany.
| | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Robach P, Lundby C. Is live high-train low altitude training relevant for elite athletes with already high total hemoglobin mass? Scand J Med Sci Sports 2012; 22:303-5. [PMID: 22612361 DOI: 10.1111/j.1600-0838.2012.01457.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
40
|
Wilhite DP, Mickleborough TD, Laymon AS, Chapman RF. Increases in $$ \dot{V} $$ O2max with “live high–train low” altitude training: role of ventilatory acclimatization. Eur J Appl Physiol 2012; 113:419-26. [DOI: 10.1007/s00421-012-2443-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 06/11/2012] [Indexed: 11/24/2022]
|
41
|
Abstract
Since the 1968 Mexico City Olympics, Kenyan and Ethiopian runners have dominated the middle- and long-distance events in athletics and have exhibited comparable dominance in international cross-country and road-racing competition. Several factors have been proposed to explain the extraordinary success of the Kenyan and Ethiopian distance runners, including (1) genetic predisposition, (2) development of a high maximal oxygen uptake as a result of extensive walking and running at an early age, (3) relatively high hemoglobin and hematocrit, (4) development of good metabolic "economy/efficiency" based on somatotype and lower limb characteristics, (5) favorable skeletal-muscle-fiber composition and oxidative enzyme profile, (6) traditional Kenyan/Ethiopian diet, (7) living and training at altitude, and (8) motivation to achieve economic success. Some of these factors have been examined objectively in the laboratory and field, whereas others have been evaluated from an observational perspective. The purpose of this article is to present the current data relative to factors that potentially contribute to the unprecedented success of Kenyan and Ethiopian distance runners, including recent studies that examined potential links between Kenyan and Ethiopian genotype characteristics and elite running performance. In general, it appears that Kenyan and Ethiopian distance-running success is not based on a unique genetic or physiological characteristic. Rather, it appears to be the result of favorable somatotypical characteristics lending to exceptional biomechanical and metabolic economy/efficiency; chronic exposure to altitude in combination with moderate-volume, high-intensity training (live high + train high), and a strong psychological motivation to succeed athletically for the purpose of economic and social advancement.
Collapse
|
42
|
Tam E, Rossi H, Moia C, Berardelli C, Rosa G, Capelli C, Ferretti G. Energetics of running in top-level marathon runners from Kenya. Eur J Appl Physiol 2012; 112:3797-806. [PMID: 22382667 DOI: 10.1007/s00421-012-2357-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2011] [Accepted: 02/14/2012] [Indexed: 11/25/2022]
Abstract
On ten top-level Kenyan marathon runners (KA) plus nine European controls (EC, equivalent to KA), we measured maximal oxygen consumption (VO2max) and the energy cost of running (Cr) on track during training camps at moderate altitude, to better understand the KA dominance in the marathon. At each incremental running speed, steady-state oxygen consumption (VO2) was measured by telemetric metabolic cart, and lactate by electro-enzymatic method. The speed requiring VO2 = VO2max provided the maximal aerobic velocity (νmax). The energy cost of running was calculated by dividing net VO2 by the corresponding speed. The speed at lactate threshold (ν(ΘAN)) was computed from individual Lâ(b) versus speed curves. The sustainable VO2max fraction (Fd) at ν(ΘAN) (F(ΘAN)) was computed dividing nu(ΘAN) by νmax. The Fd for the marathon (Fmar) was determined as Fmar = 0.92 F(ΘAN). Overall, VO2max (64.9 ± 5.8 vs. 63.9 ± 3.7 ml kg(-1) min(-1)), νmax (5.55 ± 0.30 vs. 5.41 ± 0.29 m s(-1)) and Cr (3.64 ± 0.28 vs. 3.63 ± 0.31 J kg(-1) m(-1)) resulted the same in KA as in EC. In both groups, Cr increased linearly with the square of speed. F(ΘAN) was 0.896 ± 0.054 in KA and 0.909 ± 0.068 in EC; Fmar was 0.825 ± 0.050 in KA and 0.836 ± 0.062 in EC (NS). Accounting for altitude, running speed predictions from present data are close to actual running performances, if F(ΘAN) instead of Fmar is taken as index of Fd. In conclusion, both KA and EC did not have a very high VO2max, but had extremely high Fd, and low Cr, equal between them. The dominance of KA over EC cannot be explained on energetic grounds.
Collapse
Affiliation(s)
- Enrico Tam
- Département de Neurosciences Fondamentales, Université de Genève, Geneva, Switzerland
| | | | | | | | | | | | | |
Collapse
|
43
|
ZIELIŃSKI JACEK, KUSY KRZYSZTOF, RYCHLEWSKI TADEUSZ. Effect of Training Load Structure on Purine Metabolism in Middle-Distance Runners. Med Sci Sports Exerc 2011; 43:1798-807. [DOI: 10.1249/mss.0b013e318215d10b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|