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Thompson KMA, Pethick WA, Clarke J, Winegarden A, Johnson E, Coates AM, Stellingwerff T, Burr JF. Blood Flow-Restricted Training and Time Trial Performance: A Cohort Study of World-Class Rowers. Med Sci Sports Exerc 2024; 56:1606-1614. [PMID: 38619968 DOI: 10.1249/mss.0000000000003459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
INTRODUCTION This study aimed to explore the potential impact of incorporating blood flow restriction (BFR) training within a training block characterized by minimal high-intensity work on 2000-m rowing ergometer time trial (TT) performance in elite/world-class rowers. Physiological markers often associated with endurance performance (maximal aerobic capacity, V̇O 2max ; blood lactate thresholds and hemoglobin mass, Hb mass ) were measured to determine whether changes are related to an improvement in performance. METHODS Using a quasi-experimental, observational study design (no control group), 2000-m TT performance, V̇O 2max , submaximal work rates eliciting blood lactate concentrations of ~2 and ~4 mmol·L -1 , and Hb mass were measured before and after 4 wk of noncompetitive season training, which included BFR rowing. BFR training consisted of 11 sessions of 2 × 10 min of BFR rowing at a workload equating to blood lactate concentrations of ~2 mmol·L -1 . Paired t -tests were used to compare pre-/postvalues, and Pearson correlation was used to examine whether physiological changes were associated with changes to TT performance. RESULTS TT performance improved in both female (1.09% ± 1.2%, ~4.6 ± 5.2 s; P < 0.01) and male (1.17% ± 0.48%, ~4.5 ± 1.9 s; P < 0.001) athletes. V̇O 2max increased in female rowers only ( P < 0.01), but both sexes had an increase in work rates eliciting blood lactate concentrations of 2 mmol·L -1 (female: 184 ± 16 to 195 ± 15 W, P < 0.01; male: 288 ± 23 to 317 ± 26 W, P = 0.04) and 4 mmol·L -1 (female: 217 ± 13 to 227 ± 14 W, P = 0.02; male: 339 ± 43 to 364 ± 39 W, P < 0.01). No changes in Hb mass (both sexes, P = 0.8) were observed. Improvements in TT performance were not related to physiological changes (all correlations P ≥ 0.2). CONCLUSIONS After 4 wk of training with BFR, the improvement in TT performance was greater than what is typical for this population. Physiological variables improved during this training block but did not explain improved TT performance.
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Affiliation(s)
- Kyle M A Thompson
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, CANADA
| | - Wendy A Pethick
- Canadian Sport Institute-Pacific, Victoria, British Columbia, CANADA
| | - Jordan Clarke
- Rowing Canada Aviron National Training Centre, North Cowichan, British Columbia, CANADA
| | - Anneke Winegarden
- Canadian Sport Institute-Pacific, Victoria, British Columbia, CANADA
| | - Elizabeth Johnson
- Canadian Sport Institute-Pacific, Victoria, British Columbia, CANADA
| | - Alexandra M Coates
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, CANADA
| | | | - Jamie F Burr
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, CANADA
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Sotiridis A, Makris A, Koskolou M, Geladas ND. On the mechanisms of stress-induced human spleen contraction: training for a higher blood oxygen-carrying capacity. Eur J Appl Physiol 2024:10.1007/s00421-024-05589-x. [PMID: 39207549 DOI: 10.1007/s00421-024-05589-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Accepted: 08/14/2024] [Indexed: 09/04/2024]
Abstract
Despite its comparatively limited size in humans, spleen has been shown able to expel red-blood cells in the circulation and thus augment blood oxygen-carrying capacity under certain physiologic conditions. In the present state-of-the-art review, the short- and long-term regulation of spleen volume will be discussed. With regards to the physiological mechanism underlying spleen contraction, sympathetic activation stands as the prime contributor to the response. A dose-dependent relationship between specific interventions of apnea, exercise and hypoxia (imposed separately or in combination) and spleen contraction alleges to the trainability of the spleen organ. The trainability of the spleen is further substantiated by virtue of cross-sectional and longitudinal studies reporting robust increases in both organ volume at rest and subsequent spleen contraction. Alternative ways to assess the relationship between hematologic gains and the magnitude of spleen contraction (i.e., the reduction of spleen volume) will be presented herein. In extension of changes in the conventional measures of hemoglobin concentration and hematocrit, assessment of hemoglobin mass and total blood volume using the (safe, low-cost and time-efficient) CO-rebreathing technique could deepen scientific knowledge on the efficiency of human spleen contraction.
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Affiliation(s)
- Alexandros Sotiridis
- Section of Sports Medicine and Biology of Exercise, School of Physical Education and Sport Science, National and Kapodistrian University of Athens, Athens, Greece.
- Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia.
| | - Anastasios Makris
- Section of Sports Medicine and Biology of Exercise, School of Physical Education and Sport Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Maria Koskolou
- Section of Sports Medicine and Biology of Exercise, School of Physical Education and Sport Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Nickos D Geladas
- Section of Sports Medicine and Biology of Exercise, School of Physical Education and Sport Science, National and Kapodistrian University of Athens, Athens, Greece
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Bennett S, Tiollier E, Owens DJ, Brocherie F, Louis JB. Implications of Heat Stress-induced Metabolic Alterations for Endurance Training. Int J Sports Med 2024; 45:422-435. [PMID: 38401534 DOI: 10.1055/a-2251-3170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2024]
Abstract
Inducing a heat-acclimated phenotype via repeated heat stress improves exercise capacity and reduces athletes̓ risk of hyperthermia and heat illness. Given the increased number of international sporting events hosted in countries with warmer climates, heat acclimation strategies are increasingly popular among endurance athletes to optimize performance in hot environments. At the tissue level, completing endurance exercise under heat stress may augment endurance training adaptation, including mitochondrial and cardiovascular remodeling due to increased perturbations to cellular homeostasis as a consequence of metabolic and cardiovascular load, and this may improve endurance training adaptation and subsequent performance. This review provides an up-to-date overview of the metabolic impact of heat stress during endurance exercise, including proposed underlying mechanisms of altered substrate utilization. Against this metabolic backdrop, the current literature highlighting the role of heat stress in augmenting training adaptation and subsequent endurance performance will be presented with practical implications and opportunities for future research.
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Affiliation(s)
- Samuel Bennett
- Center for Biological Clocks Research, Texas A&M University, College Station, United States
| | - Eve Tiollier
- Laboratory Sport, Expertise and Performance, Research Department, Institut National du Sport de l'Expertise et de la Performance, Paris, France
| | - Daniel J Owens
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom of Great Britain and Northern Ireland
| | - Franck Brocherie
- Laboratory Sport, Expertise and Performance, Research Department, Institut National du Sport de l'Expertise et de la Performance, Paris, France
| | - Julien B Louis
- Laboratory Sport, Expertise and Performance, Research Department, Institut National du Sport de l'Expertise et de la Performance, Paris, France
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom of Great Britain and Northern Ireland
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Wen J, Cheng J, Wang L, Li C, Zou Y, Wu J, Liu J. Dynamic molecular choreography induced by acute heat exposure in human males: a longitudinal multi-omics profiling study. Front Public Health 2024; 12:1384544. [PMID: 38813424 PMCID: PMC11135052 DOI: 10.3389/fpubh.2024.1384544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Accepted: 05/02/2024] [Indexed: 05/31/2024] Open
Abstract
Introduction Extreme heat events caused by occupational exposure and heat waves are becoming more common. However, the molecular changes underlying the response to heat exposure in humans remain to be elucidated. Methods This study used longitudinal multi-omics profiling to assess the impact of acute heat exposure (50°C for 30 min) in 24 subjects from a mine rescue team. Intravenous blood samples were collected before acute heat exposure (baseline) and at 5 min, 30 min, 1 h, and 24 h after acute heat exposure (recovery). In-depth multi-omics profiling was performed on each sample, including plasma proteomics (untargeted) and metabolomics (untargeted). Results After data curation and annotation, the final dataset contained 2,473 analytes, including 478 proteins and 1995 metabolites. Time-series analysis unveiled an orchestrated molecular choreography of changes involving the immune response, coagulation, acid-base balance, oxidative stress, cytoskeleton, and energy metabolism. Further analysis through protein-protein interactions and network analysis revealed potential regulators of acute heat exposure. Moreover, novel blood-based analytes that predicted change in cardiopulmonary function after acute heat exposure were identified. Conclusion This study provided a comprehensive investigation of the dynamic molecular changes that underlie the complex physiological processes that occur in human males who undergo heat exposure. Our findings will help health impact assessment of extreme high temperature and inspire future mechanistic and clinical studies.
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Affiliation(s)
- Jirui Wen
- Department of Otolaryngology-Head and Neck Surgery, Deep Underground Space Medical Center, West China Hospital, Sichuan University, Guoxuexiang, Chengdu, China
- Jinping Deep Underground Frontier Science and Dark Matter Key Laboratory of Sichuan Province, Liangshan, China
- State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering, Sichuan University, Chengdu, China
| | - Juan Cheng
- Department of Otolaryngology-Head and Neck Surgery, Deep Underground Space Medical Center, West China Hospital, Sichuan University, Guoxuexiang, Chengdu, China
| | - Ling Wang
- Department of Otolaryngology-Head and Neck Surgery, Deep Underground Space Medical Center, West China Hospital, Sichuan University, Guoxuexiang, Chengdu, China
- Jinping Deep Underground Frontier Science and Dark Matter Key Laboratory of Sichuan Province, Liangshan, China
| | - Can Li
- Department of Otolaryngology-Head and Neck Surgery, Deep Underground Space Medical Center, West China Hospital, Sichuan University, Guoxuexiang, Chengdu, China
| | - Yuhao Zou
- Department of Otolaryngology-Head and Neck Surgery, Deep Underground Space Medical Center, West China Hospital, Sichuan University, Guoxuexiang, Chengdu, China
| | - Jiang Wu
- Department of Otolaryngology-Head and Neck Surgery, Deep Underground Space Medical Center, West China Hospital, Sichuan University, Guoxuexiang, Chengdu, China
- Jinping Deep Underground Frontier Science and Dark Matter Key Laboratory of Sichuan Province, Liangshan, China
- Med-X Center for Manufacturing, Sichuan University, Chengdu, China
| | - Jifeng Liu
- Department of Otolaryngology-Head and Neck Surgery, Deep Underground Space Medical Center, West China Hospital, Sichuan University, Guoxuexiang, Chengdu, China
- Jinping Deep Underground Frontier Science and Dark Matter Key Laboratory of Sichuan Province, Liangshan, China
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Girard O, Peeling P, Racinais S, Périard JD. Combining Heat and Altitude Training to Enhance Temperate, Sea-Level Performance. Int J Sports Physiol Perform 2024; 19:322-327. [PMID: 38237571 DOI: 10.1123/ijspp.2023-0250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 11/29/2023] [Accepted: 12/18/2023] [Indexed: 03/01/2024]
Abstract
BACKGROUND Repeated exposure to heat (ie, plasma volume expansion) or altitude (ie, increase in total hemoglobin mass), in conjunction with exercise, induces hematological adaptations that enhance endurance performance in each respective environment. Recently, combining heat and altitude training has become increasingly common for athletes preparing to compete in temperate, sea-level conditions. PURPOSE To review the physiological adaptations to training interventions combining thermal and hypoxic stimuli and summarize the implications for temperate, sea-level performance. Current Evidence: To date, research on combining heat and hypoxia has employed 2 main approaches: simultaneously combining the stressors during training or concurrently training in the heat and sleeping at altitude, sometimes with additional training in hypoxia. When environmental stimuli are combined in a training session, improvements in aerobic fitness and time-trial performance in temperate, sea-level conditions are generally similar in magnitude to those observed with heat, or altitude, training alone. Similarly, training in the heat and sleeping at altitude does not appear to provide any additional hematological or nonhematological benefits for temperate; sea-level performance relative to training in hot, hypoxic, or control conditions. CONCLUSIONS Current research regarding combined heat and altitude interventions does not seem to indicate that it enhances temperate, sea-level performance to a greater extent than "traditional" (heat or hypoxia alone) training approaches. A major challenge in implementing combined-stressor approaches lies in the uncertainty surrounding the prescription of dosing regimens (ie, exercise and environmental stress). The potential benefits of conducting heat and altitude exposure sequentially (ie, one after the other) warrants further investigation.
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Affiliation(s)
- Olivier Girard
- School of Human Sciences (Exercise and Sport Science), University of Western Australia, Perth, WA, Australia
| | - Peter Peeling
- School of Human Sciences (Exercise and Sport Science), University of Western Australia, Perth, WA, Australia
- Western Australian Institute of Sport, Mt Claremont, WA, Australia
| | - Sébastien Racinais
- Environmental Stress Unit, CREPS Montpellier-Font Romeu, Montpellier, France
| | - Julien D Périard
- Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT, Australia
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Thompson KMA, Gamble ASD, Kontro H, Lee JB, Burr JF. Low- and high-volume blood-flow restriction treadmill walking both improve maximal aerobic capacity independently of blood volume. Scand J Med Sci Sports 2024; 34:e14534. [PMID: 37961932 DOI: 10.1111/sms.14534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 10/22/2023] [Accepted: 10/26/2023] [Indexed: 11/15/2023]
Abstract
AIM Assess the effect of low- and high-volume blood flow restriction training (BFR) on maximal aerobic capacity (VO2 max) and determine if alteration in VO2 max is mediated through changes in hemoglobin mass (Hbmass) and blood volume. METHODS Participants' Hbmass (CO-rebreathe), single, and double-leg VO2 max and blood volume regulating hormonal responses (renin and copeptin) were measured before and after BFR training. Training consisted of treadmill walking either (1) twice-daily for 4week (CON and BFRHV ) or (2) twice-weekly for 6week (BFRLV ). Each session consisted of five intervals (3 min, 5% incline, 5 km/h, 100% of lowest occlusion pressure), with 1 min of standing rest between sets. RESULTS VO2 max increased using both training exposures, in as quickly as 2-weeks (BFRLV baseline to 4week: +315 ± 241 mL (8.7%), p = 0.02; BFRHV baseline to 2week: +360 ± 261 mL (7.9%), p < 0.01), for the BFRLV and BFRHV groups, with no change in CON. Single- and double-leg VO2 max improved proportionately (single/double-leg VO2 max ratio: BFRLV 78 ± 4.9-78 ± 5.8%, BFRHV 79 ± 6.5-77 ± 6.5%), suggesting that the mechanism for increased VO2 max is not solely limited to central or peripheral adaptations. Hbmass remained unchanged across groups (CON: +10.2 ± 34 g, BFRLV : +6.6 ± 42 g, BFRHV : +3.2 ± 44 g; p = 0.9), despite a significant release of blood volume regulating hormones after initial BFR exposure (renin +20.8 ± 21.9 ng/L, p < 0.01; copeptin +22.0 ± 23.8 pmol/L, p < 0.01), which was blunted following BFRHV training (renin: +13.4 ± 12.4 ng/L, p = 0.09; copeptin: +1.9 ± 1.7 pmol/L, p = 0.98). CONCLUSION BFR treadmill walking increases VO2 max irrespective of changes in Hbmass or blood volume despite a large release of blood volume regulating hormones in response to BFR treadmill walking.
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Affiliation(s)
- K M A Thompson
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - A S D Gamble
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - H Kontro
- Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - J B Lee
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - J F Burr
- Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
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Nybo L, Rønnestad B, Lundby C. High or hot-Perspectives on altitude camps and heat-acclimation training as preparation for prolonged stage races. Scand J Med Sci Sports 2024; 34:e14268. [PMID: 36350277 DOI: 10.1111/sms.14268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/19/2022] [Accepted: 10/19/2022] [Indexed: 11/11/2022]
Abstract
Adaptation to heat stress and hypoxia are relevant for athletes participating in Tour de France or similar cycling races taking place during the summertime in landscapes with varying altitude. Both to minimize detrimental performance effects associated with arterial desaturation occurring at moderate altitudes in elite athletes, respectively, reduce the risk of hyperthermia on hot days, but also as a pre-competition acclimatization strategy to boost blood volume in already highly adapted athletes. The hematological adaptations require weeks of exposure to manifest, but are attractive as an augmented hemoglobin mass may improve arterial oxygen delivery and hence benefit prolonged performances. Altitude training camps have in this context a long history in exercise physiology and are still common practice in elite cycling. However, heat-acclimation training provides an attractive alternative for some athletes either as a stand-alone approach or in combination with altitude. The present paper provides an update and practical perspectives on the potential to utilize hypoxia and heat exposure to optimize hematological adaptations. Furthermore, we will consider temporal aspects both in terms of onset and decay of the adaptations relevant for improved thermoregulatory capacity and respiratory adaptations to abate arterial desaturation during altitude exposure. From focus on involved physiological mechanisms, time course, and responsiveness in elite athletes, we will provide guidance based on our experience from practical implementation in cyclists preparing for prolonged stage races such as the Tour de France.
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Affiliation(s)
- Lars Nybo
- Department of Nutrition, Exercise and Sport, University of Copenhagen, Copenhagen, Denmark
| | - Bent Rønnestad
- Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Carsten Lundby
- Inland Norway University of Applied Sciences, Lillehammer, Norway
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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.
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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
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Tebeck ST, Buckley JD, Stanley J. Longitudinal haematological responses to training load and heat acclimation preceding a male team pursuit cycling world record. Eur J Sport Sci 2023; 23:1859-1867. [PMID: 36404735 DOI: 10.1080/17461391.2022.2150896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study evaluated relationships between changes in training load, haematological responses, and endurance exercise performance during temperate and heat acclimation (HA) training preceding a male team cycling pursuit world record (WR). Haemoglobin mass (Hbmass) and concentration ([Hb]), plasma volume (PV) and blood volume (BV) were assessed in nine male track endurance cyclists (∼3 occasions per month) training in temperate conditions (247-142 days prior to the WR) to establish responses to differing acute (ATL) and chronic (CTL) training loads. Testing was performed again pre- and post-HA (22-28 days prior to the WR). Endurance performance (V̇O₂max, 4MMP, lactate threshold 1 and 2) was assessed on three occasions (238-231, 189-182 and 133-126 days prior to the WR). In temperate conditions, CTL was associated with Hbmass (B = 0.62, P = 0.02), PV (B = 4.49, P = 0.01) and BV (B = 6.51, P = 0.04) but not [Hb] (B = -0.01, P = 0.17). ATL was associated with PV (B = 2.28, P < 0.01), BV (B = 2.63, P = 0.04) and [Hb] (B = -0.01, P = 0.04) but not Hbmass (B = 0.10, P = 0.41). During HA, PV increased 8.2% (P < 0.01), while Hbmass, CTL and ATL were unchanged. Hbmass and [Hb] were associated with all performance outcomes (P < 0.05), except V̇O2max. PV and BV were not associated with performance outcomes. During temperate training, changes in Hbmass were most strongly associated with changes in CTL. Both CTL and ATL were associated with changes in PV, but HA was associated with increased PV and maintenance of Hbmass without increasing ATL or CTL. In practical terms, maintaining high CTL and high Hbmass might be beneficial for improving endurance performance.HIGHLIGHTSChanges in haemoglobin mass were associated with endurance exercise performance and changes in chronic training load in temperate conditions.Heat acclimation increased plasma volume and maintained haemoglobin mass independently of chronic training load.Chronic training loads and haemoglobin mass should be increased to improve endurance exercise performance.Heat acclimation may optimise haematological adaptations when training load is reduced.
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Affiliation(s)
- Samuel T Tebeck
- Department of Sports Science, South Australian Sports Institute, Adelaide, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), UniSA Allied Health & Human Performance, University of South Australia, Adelaide, Australia
| | - Jonathan D Buckley
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), UniSA Allied Health & Human Performance, University of South Australia, Adelaide, Australia
| | - Jamie Stanley
- Department of Sports Science, South Australian Sports Institute, Adelaide, Australia
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), UniSA Allied Health & Human Performance, University of South Australia, Adelaide, Australia
- Australian Cycling Team, Cycling Australia, Adelaide, Australia
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Périard JD, Girard O, Townsend N, Bourdon P, Cocking S, Ihsan M, Lacome M, Nichols D, Travers G, Wilson MG, Piscione J, Racinais S. Hematological Adaptations Following a Training Camp in Hot and/or Hypoxic Conditions in Elite Rugby Union Players. Int J Sports Physiol Perform 2023; 18:1053-1061. [PMID: 37553108 DOI: 10.1123/ijspp.2023-0166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/30/2023] [Accepted: 07/08/2023] [Indexed: 08/10/2023]
Abstract
PURPOSE To investigate the effects of a training camp with heat and/or hypoxia sessions on hematological and thermoregulatory adaptations. METHODS Fifty-six elite male rugby players completed a 2-week training camp with 5 endurance and 5 repeated-sprint sessions, rugby practice, and resistance training. Players were separated into 4 groups: CAMP trained in temperate conditions at sea level, HEAT performed the endurance sessions in the heat, ALTI slept and performed the repeated sprints at altitude, and H + A was a combination of the heat and altitude groups. RESULTS Blood volume across all groups increased by 140 mL (95%CI, 42-237; P = .006) and plasma volume by 97 mL (95%CI 28-167; P = .007) following the training camp. Plasma volume was 6.3% (0.3% to 12.4%) higher in HEAT than ALTI (P = .034) and slightly higher in HEAT than H + A (5.6% [-0.3% to 11.7%]; P = .076). Changes in hemoglobin mass were not significant (P = .176), despite a ∼1.2% increase in ALTI and H + A and a ∼0.7% decrease in CAMP and HEAT. Peak rectal temperature was lower during a postcamp heat-response test in HEAT (0.3 °C [0.1-0.5]; P = .010) and H + A (0.3 °C [0.1-0.6]; P = .005). Oxygen saturation upon waking was lower in ALTI (3% [2% to 5%]; P < .001) and H + A (4% [3% to 6%]; P < .001) than CAMP and HEAT. CONCLUSION Although blood and plasma volume increased following the camp, sleeping at altitude impeded the increase when training in the heat and only marginally increased hemoglobin mass. Heat training induced adaptations commensurate with partial heat acclimation; however, combining heat training and altitude training and confinement during a training camp did not confer concomitant hematological adaptations.
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Affiliation(s)
- Julien D Périard
- Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT,Australia
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
| | - Olivier Girard
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
- School of Human Sciences (Exercise and Sport Science), University of Western Australia, Crawley, WA,Australia
| | - Nathan Townsend
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
- College of Health and Life Sciences, Hamad Bin Khalifa University, Doha,Qatar
| | - Pitre Bourdon
- Department of Sport Science, ASPIRE, Academy for Sports Excellence, Doha,Qatar
- Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, SA,Australia
| | - Scott Cocking
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
- Department of Sport Science, ASPIRE, Academy for Sports Excellence, Doha,Qatar
| | - Mohammed Ihsan
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
| | - Mathieu Lacome
- Department of Research, Sport Laboratory, Expertise and Performance, French Institute of Sports (INSEP), Paris,France
- Department of Performance and Analytics, Parma Calcio, Parma,Italy
| | - David Nichols
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
| | - Gavin Travers
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
- Space Medicine Team, European Astronaut Center, Köln,Germany
| | - Mathew G Wilson
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
- Institute of Sport, Exercise and Health, University College London, London,United Kingdom
| | - Julien Piscione
- Department of Research, Sport Laboratory, Expertise and Performance, French Institute of Sports (INSEP), Paris,France
| | - Sebastien Racinais
- Department of Research and Scientific Support, Aspetar Orthopedic and Sports Medicine Hospital, Doha,Qatar
- Department of Research, Sport Laboratory, Expertise and Performance, French Institute of Sports (INSEP), Paris,France
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11
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Peel J, John K, Page J, Scott G, Jeffries O, Heffernan S, Tallent J, Waldron M. Factors contributing to the change in thermoneutral maximal oxygen consumption after iso-intensity heat acclimation programmes. Eur J Sport Sci 2023:1-10. [PMID: 36533403 DOI: 10.1080/17461391.2022.2160278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The factors explaining variance in thermoneutral maximal oxygen uptake (V˙O2max) adaptation to heat acclimation (HA) were evaluated, with consideration of HA programme parameters, biophysical variables and thermo-physiological responses. Seventy-one participants consented to perform iso-intensity training (range: 45%-55% V˙O2max) in the heat (range: 30°C-38°C; 20%-60% relative humidity) on consecutive days (range: 5-days-14-days) for between 50-min and-90 min. The participants were evaluated for their thermoneutral V˙O2max change pre-to-post HA. Participants' whole-body sweat rate, heart rate, core temperature, perceived exertion and thermal sensation and plasma volume were measured, and changes in these responses across the programme determined. Partial least squares regression was used to explain variance in the change in V˙O2max across the programme using 24 variables. Sixty-three percent of the participants increased V˙O2max more than the test error, with a mean ± SD improvement of 2.6 ± 7.9%. A two-component model minimised the root mean squared error and explained the greatest variance (R2; 65%) in V˙O2max change. Eight variables positively contributed (P < 0.05) to the model: exercise intensity (%V˙O2max), ambient temperature, HA training days, total exposure time, baseline body mass, thermal sensation, whole-body mass losses and the number of days between the final day of HA and the post-testing day. Within the ranges evaluated, iso-intensity HA improved V˙O2max 63% of the time, with intensity - and volume-based parameters, alongside sufficient delays in post-testing being important considerations for V˙O2max maximisation. Monitoring of thermal sensation and body mass losses during the programme offers an accessible way to gauge the degree of potential adaptation.
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Affiliation(s)
- Jenny Peel
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
| | - Kevin John
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
| | - Joe Page
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
| | - Georgia Scott
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
| | - Owen Jeffries
- School of Biomedical, Nutritional and Sport Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Shane Heffernan
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK
| | - Jamie Tallent
- School of Sport, Rehabilitation, and Exercise Sciences, University of Essex, Colchester, UK.,Department of Physiotherapy, Faculty of Medicine, Nursing and Health Sciences, School of Primary and Allied Health Care, Monash University, Melbourne, Australia
| | - Mark Waldron
- A-STEM Centre, Faculty of Science & Engineering, Swansea University, Swansea, UK.,Welsh Institute of Performance Science, Swansea University, Swansea, UK.,School of Health and Behavioural Sciences, University of the Sunshine Coast, Queensland, Australia
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12
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Sitkowski D, Cisoń T, Szygula Z, Surała O, Starczewski M, Sadowska D, Malczewska-Lenczowska J. Hematological Adaptations to Post-Exercise Sauna Bathing With No Fluid Intake: A Randomized Cross-Over Study. RESEARCH QUARTERLY FOR EXERCISE AND SPORT 2022; 93:795-803. [PMID: 34727008 DOI: 10.1080/02701367.2021.1921684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 04/21/2021] [Indexed: 06/13/2023]
Abstract
Purpose: Sauna bathing is recommended to improve the sports training process, yet empirical evidence confirming its effectiveness is still inconclusive. We examined the effects of post-exercise sauna bathing on hematological adaptations and exercise capacity in healthy men. Methods: Thirteen physical education students participated in randomized cross-over study: two, 4-week interventions, with 10-week washout. The interventions involved 3 times per week 60-min stationary cycling either with 30-min of post-exercise sauna bathing (89 ± 3°C, 10 ± 2% RH) or without; no fluid was ingested during both exercise and sauna sessions. Before and after both interventions, participants were tested for total hemoglobin mass (tHb-mass), intravascular volumes, erythropoietin, ferritin, red blood cell parameters with reticulocyte fractions, along with maximal/peak and submaximal variables in a graded exercise test (GXT). Results: Regardless of intervention type, tHb-mass increased (p = .014) whereas ferritin concentration decreased (p = .027); however, changes in tHb-mass were within the range of typical error (<1.8%). Absolute and relative values of maximal power and power at gas exchange threshold, as well as peak oxygen uptake (all p < .010), also increased irrespective of intervention type. Conclusions: The use of post-exercise sauna bathing with fluid intake restrictions does not provide any additional benefits in tested variables over endurance training alone. Thus, further evidence is required before recommendations to utilize this post-exercise conditioning strategy are deemed valid.
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Affiliation(s)
| | - Tomasz Cisoń
- State University of Applied Sciences in Nowy Sącz
| | | | - Olga Surała
- Institute of Sport - National Research Institute
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13
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Royal JT, Fisher JT, Mlinar T, Mekjavic IB, McDonnell AC. Validity and reliability of capillary vs. Venous blood for the assessment of haemoglobin mass and intravascular volumes. Front Physiol 2022; 13:1021588. [PMID: 36505074 PMCID: PMC9730879 DOI: 10.3389/fphys.2022.1021588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 11/14/2022] [Indexed: 11/25/2022] Open
Abstract
Objectives: Haemoglobin mass (Hbmass) assessment with the carbon monoxide rebreathing method is a more accurate estimate than other measures of oxygen-carrying capacity. Blood may be collected by several means and differences in the measured variables may exist as a result. The present study assessed the validity and reliability of calculated Hbmass and intravascular volumes obtained from capillary blood (CAP) when compared to venous blood (VEN) draws. Methods: Twenty-two adults performed a carbon monoxide rebreathing procedure with paired VEN and CAP draws at baseline, pre-rebreathing and post-rebreathing (POST). Thirteen of these participants performed this protocol on two occasions to assess the data reliability from both blood sampling sites. In a second experiment, 14 adults performed a 20-min seated and a 20-min supine rest to assess for the effect of posture on haematological parameters. Results: Haemoglobin mass (CAP = 948.8 ± 156.8 g; VEN = 943.4 ± 157.3 g, p = 0.108) and intravascular volume (CAP = 6.5 ± 1 L; VEN = 6.5 ± 0.9 L, p = 0.752) were statistically indifferent, had low bias (Hbmass bias = 14.45 ± 40.42 g, LoA -64.78 g-93.67 g) and were highly correlated between sampling techniques. Reliability analysis demonstrated no difference in the mean change in variables calculated from both sampling sites and good to excellent intraclass correlation coefficients (>0.700), however, typical measurement error was larger in variables measured using CAP (VEN Hbmass TE% = 2.1%, CAP Hbmass TE% = 5.5%). The results indicate that a supine rest prior to the rebreathing protocol would have a significant effect on haemoglobin concentration and haematocrit values compared to a seated rest, with no effect on carboxyhaemoglobin %. Conclusion: The present study demonstrates that CAP and VEN were comparable for the calculation of Hbmass and intravascular volumes in terms of accuracy. However, reduced reliability and increased error in the CAP variables indicates that there are methodological considerations to address when deciding which blood drawing technique to utilise. To reduce this CAP error, increased replicate analyses are required.
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Affiliation(s)
- Joshua T. Royal
- Department of Automation, Biocybernetics, and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia,Jozef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Jason T. Fisher
- Department of Automation, Biocybernetics, and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia,Jozef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Tinkara Mlinar
- Department of Automation, Biocybernetics, and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia,Jozef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Igor B. Mekjavic
- Department of Automation, Biocybernetics, and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia,Department of Biomedical Physiology and Kinesiology, Simon Fraser University Burnaby, Burnaby, BC, Canada
| | - Adam C. McDonnell
- Department of Automation, Biocybernetics, and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia,*Correspondence: Adam C. McDonnell,
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14
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Kellenberger K, Steiner T, Wehrlin JP. Comparison of the automatised and the optimised carbon monoxide rebreathing methods. Scandinavian Journal of Clinical and Laboratory Investigation 2022; 82:474-480. [PMID: 36129418 DOI: 10.1080/00365513.2022.2122078] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Recently, a new automated carbon monoxide (CO) rebreathing method (aCO) to estimate haemoglobin mass (Hbmass) was introduced. The aCO method uses the same CO dilution principle as the widely used optimised CO rebreathing method (oCO). The two methods differ in terms of CO administration, body position, and rebreathing time. Whereas with aCO, CO is administered automatically by the system in a supine position of the subject, with oCO, CO is administered manually by an experienced operator with the subject sitting. Therefore, the aim of this study was to quantify possible differences in Hbmass estimated with the two methods. Hbmass was estimated in 18 subjects (9 females, 9 males) with oCO using capillary blood samples (oCOc) and aCO taking simultaneously venous blood samples (aCOv) and capillary blood samples (aCOc). Overall, Hbmass was different between the three measurement procedures (F = 57.55, p < .001). Hbmass was lower (p < .001) for oCOc (737 g ± 179 g) than for both aCOv (825 g ± 189 g, -9.3%) and aCOc (835 g ± 189 g, -10.6%). There was no difference in Hbmass estimated with aCOv and aCOc procedures (p = .12). Three factors can likely explain the 10% difference in Hbmass: differences in calculations (including a factor for myoglobin flux), body position (distribution of CO in blood circulation) during rebreathing, and time of blood sampling. Moreover, the determination of Hbmass with aCO is possible with capillary blood sampling instead of venous blood sampling.
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Affiliation(s)
- Katja Kellenberger
- Section for Elite Sport, Swiss Federal Institute of Sport, Magglingen, Switzerland
| | - Thomas Steiner
- Section for Elite Sport, Swiss Federal Institute of Sport, Magglingen, Switzerland
| | - Jon Peter Wehrlin
- Section for Elite Sport, Swiss Federal Institute of Sport, Magglingen, Switzerland
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15
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RØNNESTAD BENTR, URIANSTAD TOMAS, HAMARSLAND HÅVARD, HANSEN JOAR, NYGAARD HÅVARD, ELLEFSEN STIAN, HAMMARSTRÖM DANIEL, LUNDBY CARSTEN. Heat Training Efficiently Increases and Maintains Hemoglobin Mass and Temperate Endurance Performance in Elite Cyclists. Med Sci Sports Exerc 2022; 54:1515-1526. [DOI: 10.1249/mss.0000000000002928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Rønnestad BR, Lid OM, Hansen J, Hamarsland H, Mølmen KS, Nygaard H, Ellefsen S, Hammarström D, Lundby C. Heat suit training increases hemoglobin mass in elite cross-country skiers. Scand J Med Sci Sports 2022; 32:1089-1098. [PMID: 35305278 PMCID: PMC9544462 DOI: 10.1111/sms.14156] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 02/18/2022] [Accepted: 03/08/2022] [Indexed: 01/29/2023]
Abstract
Purpose The primary purpose was to test the effect of heat suit training on hemoglobin mass (Hbmass) in elite cross‐country (XC) skiers. Methods Twenty‐five male XC‐skiers were divided into a group that added 5 × 50 min weekly heat suit training sessions to their regular training (HEAT; n = 13, 23 ± 5 years, 73.9 ± 5.2 kg, 180 ± 6 cm, 76.8 ± 4.6 ml·min−1·kg−1) or to a control group matched for training volume and intensity distribution (CON; n = 12, 23 ± 4 years, 78.4 ± 5.8 kg, 184 ± 4 cm, 75.2 ± 3.4 ml·min−1·kg−1) during the five‐week intervention period. Hbmass, endurance performance and factors determining endurance performance were assessed before and after the intervention. Results HEAT led to 30 g greater Hbmass (95% CI: [8.5, 51.7], p = 0.009) and 157 ml greater red blood cell volume ([29, 285], p = 0.018) post‐intervention, compared to CON when adjusted for baseline values. In contrast, no group differences were observed for changes in work economy, running velocity, and fractional utilization of maximal oxygen uptake (V̇O2max) at 4 mmol·L−1 blood lactate, V̇O2max or 15‐min running distance performance trial during the intervention. Conclusion HEAT induced a larger increase in Hbmass and red blood cell volume after five weeks with five weekly heat suit training sessions than CON, but with no detectable group differences on physiological determinants of endurance performance or actual endurance performance in elite CX skiers.
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Affiliation(s)
| | - Ole Martin Lid
- Inland University of Applied Sciences, Lillehammer, Norway
| | - Joar Hansen
- Inland University of Applied Sciences, Lillehammer, Norway
| | | | | | - Håvard Nygaard
- Inland University of Applied Sciences, Lillehammer, Norway
| | - Stian Ellefsen
- Inland University of Applied Sciences, Lillehammer, Norway
| | | | - Carsten Lundby
- Inland University of Applied Sciences, Lillehammer, Norway
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17
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Borg DN, O'Brien JL. Comment on "Effects of Heat Acclimation and Acclimatisation on Maximal Aerobic Capacity Compared to Exercise Alone in Both Thermoneutral and Hot Environments: A Meta-Analysis and Meta-Regression". Sports Med 2022; 52:1715-1718. [PMID: 34874545 DOI: 10.1007/s40279-021-01611-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/21/2021] [Indexed: 11/26/2022]
Affiliation(s)
- David N Borg
- Menzies Health Institute Queensland, The Hopkins Centre, Griffith University, Brisbane, Australia.
- School of Health Sciences and Social Work, Griffith University, Brisbane, Australia.
| | - Julia L O'Brien
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia
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18
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Almquist NW, Sandbakk Ø, Solli GS. Performance-Related Physiological and Haematological Changes During Pregnancy and Postpartum in a Well-Trained Cyclist Performing Endurance Training. Front Physiol 2022; 13:762950. [PMID: 35615680 PMCID: PMC9125089 DOI: 10.3389/fphys.2022.762950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 04/13/2022] [Indexed: 11/22/2022] Open
Abstract
Purpose: To describe the performance-related physiological and haematological changes in a well-trained cyclist (peak oxygen uptake, VO2peak: 54.9 ml min-1·kg-1) performing endurance training during pregnancy and postpartum. Methods: Training data was systemized by training form (endurance and resistance), intensity (low- (LIT), moderate-, and high-intensity training), and modality (cycling, running, hiking, XC-skiing, strength training and other). Power output at 4 mmol L-1 [BLa-] (L4), maximal aerobic power (Wmax), and VO2peak as well as haemoglobin mass, blood volume, plasma volume and red blood cell volume (RBCV) were measured at different time points during pregnancy and 12 weeks postpartum. Results: L4 and Wmax increased by 3% while absolute VO2peak was unaltered from gestational wk 2 to 14, despite 12 and 14% increases in RBCV and BV. After delivery, BV was reduced by 7% but RBCV was maintained 5% above start-pregnancy levels, while VO2peak almost returned to (-1%), and Wmax increased by 5% above start-pregnancy levels 12 weeks postpartum. Conclusion: This case-study illustrates a disassociation between increases in haematological values and VO2peak during pregnancy. Furthermore, a quick resumption of LIT and a gradually increasing intensity of training in the 12 weeks following delivery ensured a return to start-pregnancy levels of VO2peak and corresponding improvements in Wmax. Although general recommendations cannot be given on the basis of these data, this study provides a framework for investigating pregnant endurance athletes and contributes to the generation of new hypotheses in this field.
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Affiliation(s)
- Nicki Winfield Almquist
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, Norway
- Department of Nutrition, Exercise and Sports, The August Krogh Section for Molecular Physiology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Øyvind Sandbakk
- Centre for Elite Sports Research, Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway
- Faculty of Health Sciences, School of Sport Sciences, UiT The Arctic University of Norway, Tromsø, Norway
| | - Guro Strøm Solli
- Faculty of Health Sciences, School of Sport Sciences, UiT The Arctic University of Norway, Tromsø, Norway
- Department of Sports Sciences and Physical Education, Nord University, Bodø, Norway
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19
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Almquist NW, Wilhelmsen M, Ellefsen S, Sandbakk Ø, Rønnestad BR. Effects of Including Sprints in LIT Sessions during a 14-d Camp on Muscle Biology and Performance Measures in Elite Cyclists. Med Sci Sports Exerc 2021; 53:2333-2345. [PMID: 34081058 DOI: 10.1249/mss.0000000000002709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE This study investigated the effects of including sprints within low-intensity training (LIT) sessions during a 14-d training camp focusing on LIT, followed by 10-d recovery (Rec), on performance and performance-related measures in elite cyclists. METHODS During the camp, a sprint training group (SPR; n = 9) included 12 × 30-s maximal sprints during five LIT sessions, whereas a control group (CON; n = 9) performed distance-matched LIT only. Training load was equally increased in both groups by 48% ± 27% during the training camp and subsequently decreased by -56% ± 23% during the recovery period compared with habitual training. Performance tests were conducted before the training camp (Pre) and after Rec. Muscle biopsies, hematological measures, and stress/recovery questionnaires were collected Pre and after the camp (Post). RESULTS Thirty-second sprint (SPR vs CON: 4% ± 4%, P < 0.01) and 5-min mean power (SPR vs CON: 4% ± 8%, P = 0.04) changed differently between groups. In muscle, Na+-K+ β1 protein content changed differently between groups, decreasing in CON compared with SPR (-8% ± 14%, P = 0.04), whereas other proteins showed similar changes. SPR and CON displayed similar increases in red blood cell volume (SPR: 2.6% ± 4.7%, P = 0.07; CON: 3.9% ± 4.5%, P = 0.02) and V˙O2 at 4 mmol·L-1 [BLa-] (SPR: 2.5% ± 3.3%, P = 0.03; CON: 2.2% ± 3.0%, P = 0.04). No changes were seen for V˙O2max, Wmax, hematological measures, muscle enzyme activity, and stress/recovery measures. CONCLUSIONS Inclusion of 30-s sprints within LIT sessions during a high-volume training camp affected competition-relevant performance measures and Na+-K+ β1 protein content differently from LIT only, without affecting sport-specific stress/recovery or any other physiological measure in elite cyclists.
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Affiliation(s)
| | - Malene Wilhelmsen
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, NORWAY
| | - Stian Ellefsen
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, NORWAY
| | - Øyvind Sandbakk
- Centre for Elite Sports Research, Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, NORWAY
| | - Bent R Rønnestad
- Section for Health and Exercise Physiology, Inland Norway University of Applied Sciences, Lillehammer, NORWAY
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20
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Lundby C, Svendsen IS, Urianstad T, Hansen J, Rønnestad BR. Training wearing thermal clothing and training in hot ambient conditions are equally effective methods of heat acclimation. J Sci Med Sport 2021; 24:763-767. [DOI: 10.1016/j.jsams.2021.06.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 05/27/2021] [Accepted: 06/07/2021] [Indexed: 10/21/2022]
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21
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Maunder E, Plews DJ, Wallis GA, Brick MJ, Leigh WB, Chang WL, Watkins CM, Kilding AE. Temperate performance and metabolic adaptations following endurance training performed under environmental heat stress. Physiol Rep 2021; 9:e14849. [PMID: 33977674 PMCID: PMC8114151 DOI: 10.14814/phy2.14849] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 04/04/2021] [Indexed: 11/24/2022] Open
Abstract
Endurance athletes are frequently exposed to environmental heat stress during training. We investigated whether exposure to 33°C during training would improve endurance performance in temperate conditions and stimulate mitochondrial adaptations. Seventeen endurance-trained males were randomly assigned to perform a 3-week training intervention in 18°C (TEMP) or 33°C (HEAT). An incremental test and 30-min time-trial preceded by 2-h low-intensity cycling were performed in 18°C pre- and post-intervention, along with a resting vastus lateralis microbiopsy. Training was matched for relative cardiovascular demand using heart rates measured at the first and second ventilatory thresholds, along with a weekly "best-effort" interval session. Perceived training load was similar between-groups, despite lower power outputs during training in HEAT versus TEMP (p < .05). Time-trial performance improved to a greater extent in HEAT than TEMP (30 ± 13 vs. 16 ± 5 W, N = 7 vs. N = 6, p = .04), and citrate synthase activity increased in HEAT (fold-change, 1.25 ± 0.25, p = .03, N = 9) but not TEMP (1.10 ± 0.22, p = .22, N = 7). Training-induced changes in time-trial performance and citrate synthase activity were related (r = .51, p = .04). A group × time interaction for peak fat oxidation was observed (Δ 0.05 ± 0.14 vs. -0.09 ± 0.12 g·min-1 in TEMP and HEAT, N = 9 vs. N = 8, p = .05). Our data suggest exposure to moderate environmental heat stress during endurance training may be useful for inducing adaptations relevant to performance in temperate conditions.
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Affiliation(s)
- Ed Maunder
- Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
| | - Daniel J Plews
- Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
| | - Gareth A Wallis
- School of Sport, Exercise, and Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Matthew J Brick
- Orthosports North Harbour, AUT Millennium, Auckland, New Zealand
| | - Warren B Leigh
- Orthosports North Harbour, AUT Millennium, Auckland, New Zealand
| | - Wee-Leong Chang
- Faculty of Health and Environmental Sciences, Auckland University of Technology, Auckland, New Zealand
| | - Casey M Watkins
- Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
| | - Andrew E Kilding
- Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
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22
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Périard JD, Eijsvogels TMH, Daanen HAM. Exercise under heat stress: thermoregulation, hydration, performance implications, and mitigation strategies. Physiol Rev 2021; 101:1873-1979. [PMID: 33829868 DOI: 10.1152/physrev.00038.2020] [Citation(s) in RCA: 149] [Impact Index Per Article: 49.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A rise in body core temperature and loss of body water via sweating are natural consequences of prolonged exercise in the heat. This review provides a comprehensive and integrative overview of how the human body responds to exercise under heat stress and the countermeasures that can be adopted to enhance aerobic performance under such environmental conditions. The fundamental concepts and physiological processes associated with thermoregulation and fluid balance are initially described, followed by a summary of methods to determine thermal strain and hydration status. An outline is provided on how exercise-heat stress disrupts these homeostatic processes, leading to hyperthermia, hypohydration, sodium disturbances, and in some cases exertional heat illness. The impact of heat stress on human performance is also examined, including the underlying physiological mechanisms that mediate the impairment of exercise performance. Similarly, the influence of hydration status on performance in the heat and how systemic and peripheral hemodynamic adjustments contribute to fatigue development is elucidated. This review also discusses strategies to mitigate the effects of hyperthermia and hypohydration on exercise performance in the heat by examining the benefits of heat acclimation, cooling strategies, and hyperhydration. Finally, contemporary controversies are summarized and future research directions are provided.
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Affiliation(s)
- Julien D Périard
- University of Canberra Research Institute for Sport and Exercise, Bruce, Australia
| | - Thijs M H Eijsvogels
- Department of Physiology, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hein A M Daanen
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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23
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Astolfi T, Crettaz von Roten F, Kayser B, Saugy M, Faiss R. The Influence of Training Load on Hematological Athlete Biological Passport Variables in Elite Cyclists. Front Sports Act Living 2021; 3:618285. [PMID: 33817634 PMCID: PMC8012815 DOI: 10.3389/fspor.2021.618285] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 02/22/2021] [Indexed: 11/13/2022] Open
Abstract
The hematological module of the Athlete Biological Passport (ABP) is used in elite sport for antidoping purposes. Its aim is to better target athletes for testing and to indirectly detect blood doping. The ABP allows to monitor hematological variations in athletes using selected primary blood biomarkers [hemoglobin concentration (Hb) and reticulocyte percentage (Ret%)] with an adaptive Bayesian model to set individual upper and lower limits. If values fall outside the individual limits, an athlete may be further targeted and ultimately sanctioned. Since (Hb) varies with plasma volume (PV) fluctuations, possibly caused by training load changes, we investigated the putative influence of acute and chronic training load changes on the ABP variables. Monthly blood samples were collected over one year in 10 male elite cyclists (25.6 ± 3.4 years, 181 ± 4 cm, 71.3 ± 4.9 kg, 6.7 ± 0.8 W.kg-1 5-min maximal power output) to calculate individual ABP profiles and monitor hematological variables. Total hemoglobin mass (Hbmass) and PV were additionally measured by carbon monoxide rebreathing. Acute and chronic training loads-respectively 5 and 42 days before sampling-were calculated considering duration and intensity (training stress score, TSSTM). (Hb) averaged 14.2 ± 0.0 (mean ± SD) g.dL-1 (range: 13.3-15.5 g·dl-1) over the study with significant changes over time (P = 0.004). Hbmass was 1030 ± 87 g (range: 842-1116 g) with no significant variations over time (P = 0.118), whereas PV was 4309 ± 350 mL (range: 3,688-4,751 mL) with a time-effect observed over the study time (P = 0.014). Higher acute-but not chronic-training loads were associated with significantly decreased (Hb) (P <0.001). Although individual hematological variations were observed, all ABP variables remained within the individually calculated limits. Our results support that acute training load variations significantly affect (Hb), likely due to short-term PV fluctuations, underlining the importance of considering training load when interpreting individual ABP variations for anti-doping purposes.
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Affiliation(s)
- Tiffany Astolfi
- REDs, Research and Expertise in Anti-Doping Sciences, University of Lausanne, Lausanne, Switzerland.,ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | | | - Bengt Kayser
- ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Martial Saugy
- REDs, Research and Expertise in Anti-Doping Sciences, University of Lausanne, Lausanne, Switzerland.,ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Raphael Faiss
- REDs, Research and Expertise in Anti-Doping Sciences, University of Lausanne, Lausanne, Switzerland.,ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
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Effects of Heat Acclimation and Acclimatisation on Maximal Aerobic Capacity Compared to Exercise Alone in Both Thermoneutral and Hot Environments: A Meta-Analysis and Meta-Regression. Sports Med 2021; 51:1509-1525. [PMID: 33811616 PMCID: PMC8222027 DOI: 10.1007/s40279-021-01445-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2021] [Indexed: 11/25/2022]
Abstract
Background Heat acclimation and acclimatisation (HA) is typically used to enhance tolerance to the heat, thereby improving performance. HA might also confer a positive adaptation to maximal oxygen consumption (\documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max), although this has been historically debated and requires clarification via meta-analysis. Objectives (1) To meta-analyse all studies (with and without control groups) that have investigated the effect of HA on \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max adaptation in thermoneutral or hot environments; (2) Conduct meta-regressions to establish the moderating effect of selected variables on \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max adaptation following HA. Methods A search was performed using various databases in May 2020. The studies were screened using search criteria for eligibility. Twenty-eight peer-reviewed articles were identified for inclusion across four separate meta-analyses: (1) Thermoneutral \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max within-participants (pre-to-post HA); (2) Hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max within-participants (pre-to-post HA); (3) Thermoneutral \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max measurement; HA vs. control groups; (4) Hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max measurement, HA vs. control groups. Meta-regressions were performed for each meta-analysis based on: isothermal vs. iso-intensity programmes, days of heat exposure, HA ambient temperature (°C), heat index, HA session duration (min), ambient thermal load (HA session x ambient temperature), mean mechanical intensity (W) and the post-HA testing period (days). Results The meta-analysis of pre–post differences in thermoneutral \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max demonstrated small-to-moderate improvements in \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max (Hedges’ g = 0.42, 95% CI 0.24–0.59, P < 0.001), whereas moderate improvements were found for the equivalent analysis of hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max changes (Hedges’ g = 0.63, 95% CI 0.26–1.00, P < 0.001), which were positively moderated by the number of days post-testing (P = 0.033, β = 0.172). Meta-analysis of control vs. HA thermoneutral \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max demonstrated a small improvement in \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max in HA compared to control (Hedges’ g = 0.30, 95% CI 0.06–0.54, P = 0.014) and this effect was larger for the equivalent hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max analysis where a higher (moderate-to-large) improvement in \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max was found (Hedges’ g = 0.75, 95% CI 0.22–1.27, P = 0.005), with the number of HA days (P = 0.018; β = 0.291) and the ambient temperature during HA (P = 0.003; β = 0.650) positively moderating this effect. Conclusion HA can enhance \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max adaptation in thermoneutral or hot environments, with or without control group consideration, by at least a small and up to a moderate–large amount, with the larger improvements occurring in the heat. Ambient heat, number of induction days and post-testing days can explain some of the changes in hot \documentclass[12pt]{minimal}
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\begin{document}$$V{\text{O}}_{2\max }$$\end{document}VO2max adaptation.
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Tipton M. Experimental Physiology special issue: Extreme environmental physiology. Exp Physiol 2020; 106:1-3. [PMID: 33382514 DOI: 10.1113/ep089151] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 11/08/2022]
Affiliation(s)
- Mike Tipton
- Extreme Environments Laboratory, School of Sport, Health & Exercise Science, University of Portsmouth, Portsmouth, UK
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Four-month operational heat acclimatization positively affects the level of heat tolerance 6 months later. Sci Rep 2020; 10:20260. [PMID: 33219295 PMCID: PMC7680124 DOI: 10.1038/s41598-020-77358-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 10/30/2020] [Indexed: 12/02/2022] Open
Abstract
Benefits obtained after heat acclimation/acclimatization should be completely lost after an estimated period of 6 weeks. However, this estimate is still hypothetical. We evaluate the long-term effects of heat acclimatization on the level of heat tolerance. Physiological and subjective markers of heat tolerance were assessed during a heat stress test (HST: 3 × 8-min runs outdoors [~ 40 °C and 20% RH] at 50% of their estimated speed at VO2max) performed on the 2nd day upon arrival to the desert military base in the United Arab Emirates after a first day of mostly passive exposure to heat. Among the 50 male French soldiers, 25 partook in a 4-month military mission in countries characterized by a hot environment ~ 6 months prior to the study (HA). The other 25 participants were never heat acclimatized (CT). Rectal temperature (p = 0.023), heart rate (p = 0.033), and perceived exertion (p = 0.043) were lower in the HA than CT group at the end of HST. Soldiers who experienced a former 4-month period of natural heat acclimatization very likely had a higher level of heat tolerance during exercise in the heat, even 6 months after returning from the previous desert mission, than that of their non-acclimatized counterparts.
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Kirby NV, Lucas SJE, Armstrong OJ, Weaver SR, Lucas RAI. Intermittent post-exercise sauna bathing improves markers of exercise capacity in hot and temperate conditions in trained middle-distance runners. Eur J Appl Physiol 2020; 121:621-635. [PMID: 33211153 PMCID: PMC7862510 DOI: 10.1007/s00421-020-04541-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 10/24/2020] [Indexed: 10/27/2022]
Abstract
PURPOSE This study investigated whether intermittent post-exercise sauna bathing across three-weeks endurance training improves exercise heat tolerance and exercise performance markers in temperate conditions, compared to endurance training alone. The subsidiary aim was to determine whether exercise-heat tolerance would further improve following 7-Weeks post-exercise sauna bathing. METHODS Twenty middle-distance runners (13 female; mean ± SD, age 20 ± 2 years, [Formula: see text]O2max 56.1 ± 8.7 ml kg-1 min-1) performed a running heat tolerance test (30-min, 9 km h-1/2% gradient, 40 °C/40%RH; HTT) and temperate (18 °C) exercise tests (maximal aerobic capacity [[Formula: see text]O2max], speed at 4 mmol L-1 blood lactate concentration ([La-]) before (Pre) and following three-weeks (3-Weeks) normal training (CON; n = 8) or normal training with 28 ± 2 min post-exercise sauna bathing (101-108 °C, 5-10%RH) 3 ± 1 times per week (SAUNA; n = 12). Changes from Pre to 3-Weeks were compared between-groups using an analysis of co-variance. Six SAUNA participants continued the intervention for 7 weeks, completing an additional HTT (7-Weeks; data compared using a one-way repeated-measures analysis of variance). RESULTS During the HTT, SAUNA reduced peak rectal temperature (Trec; - 0.2 °C), skin temperature (- 0.8 °C), and heart rate (- 11 beats min-1) more than CON at 3-Weeks compared to Pre (all p < 0.05). SAUNA also improved [Formula: see text]O2max (+ 0.27 L-1 min-1; p = 0.02) and speed at 4 mmol L-1 [La-] (+ 0.6 km h-1; p = 0.01) more than CON at 3-Weeks compared to Pre. Only peak Trec (- 0.1 °C; p = 0.03 decreased further from 3-Weeks to 7-Weeks in SAUNA (other physiological variables p > 0.05). CONCLUSIONS Three-weeks post-exercise sauna bathing is an effective and pragmatic method of heat acclimation, and an effective ergogenic aid. Extending the intervention to seven weeks only marginally improved Trec.
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