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Cebrián-Ponce Á, Marini E, Stagi S, Castizo-Olier J, Carrasco-Marginet M, Garnacho-Castaño MV, Noriega Z, Espasa-Labrador J, Irurtia A. Body fluids and muscle changes in trail runners of various distances. PeerJ 2023; 11:e16563. [PMID: 38054016 PMCID: PMC10695110 DOI: 10.7717/peerj.16563] [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: 09/20/2023] [Accepted: 11/12/2023] [Indexed: 12/07/2023] Open
Abstract
Background This study aims to investigate body fluids and muscle changes evoked by different trail races using anthropometric, bioelectrical, and creatine kinase (CK) measurements. Methods A total of 92 subjects (55 men, 37 women) participating in three different races of 14, 35, and 52 km were evaluated before (PRE) and after (POST) the races. Classic bioelectrical impedance vector analysis was applied at the whole-body level (WB-BIVA). Additionally, muscle-localized bioelectrical assessments (ML-BIVA) were performed in a subgroup of 11 men (in the quadriceps, hamstrings, and calves). PRE-POST differences and correlations between bioelectrical values and CK, running time and race distance were tested. Results Changes in whole-body vectors and phase angles disclosed an inclination towards dehydration among men in the 14, 35, and 52 km groups (p < 0.001), as well as among women in the 35 and 52 km groups (p < 0.001). PRE Z/H was negatively correlated with running time in the 35 km men group and 14 km women group (r = -0.377, p = 0.048; r = -0.751, p = 0.001; respectively). POST Z/H was negatively correlated with running time in the 14 km women group (r = -0.593, p = 0.02). CK was positively correlated with distance in men and women (p < 0.001) and negatively correlated with reactance and vector length in the 14 km men group (p < 0.05). ML-BIVA echoed the same tendency as the WB-BIVA in the 35 and 52 km runners, with the most notable changes occurring in the calves (p < 0.001). Conclusions WB-BIVA and CK measurements underscored a conspicuous trend towards post-race dehydration and muscle damage, displaying a weak association with performance. Notably, ML-BIVA detected substantial alterations primarily in the calves. The study underscores the utility of BIVA as a technique to assess athlete's body composition changes.
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Affiliation(s)
- Álex Cebrián-Ponce
- INEFC-Barcelona Sports Sciences Research Group, National Institute of Physical Education of Catalonia (INEFC). University of Barcelona (UB), Barcelona, Spain
| | - Elisabetta Marini
- Department of Life and Environmental Sciences. Neuroscience and Anthropology Section, University of Cagliari, Cagliari, Italy
| | - Silvia Stagi
- Department of Life and Environmental Sciences. Neuroscience and Anthropology Section, University of Cagliari, Cagliari, Italy
| | - Jorge Castizo-Olier
- INEFC-Barcelona Sports Sciences Research Group, National Institute of Physical Education of Catalonia (INEFC). University of Barcelona (UB), Barcelona, Spain
- DAFNiS Research Group (Pain, Physical Activity, Nutrition and Health), Campus Docent Sant Joan de Déu, University of Barcelona, Barcelona, Spain
| | - Marta Carrasco-Marginet
- INEFC-Barcelona Sports Sciences Research Group, National Institute of Physical Education of Catalonia (INEFC). University of Barcelona (UB), Barcelona, Spain
| | - Manuel Vicente Garnacho-Castaño
- DAFNiS Research Group (Pain, Physical Activity, Nutrition and Health), Campus Docent Sant Joan de Déu, University of Barcelona, Barcelona, Spain
- Faculty of Health Sciences, Valencian International University (VIU), Valencia, Spain
| | - Zeasseska Noriega
- INEFC-Barcelona Sports Sciences Research Group, National Institute of Physical Education of Catalonia (INEFC). University of Barcelona (UB), Barcelona, Spain
| | - Javier Espasa-Labrador
- INEFC-Barcelona Sports Sciences Research Group, National Institute of Physical Education of Catalonia (INEFC). University of Barcelona (UB), Barcelona, Spain
| | - Alfredo Irurtia
- INEFC-Barcelona Sports Sciences Research Group, National Institute of Physical Education of Catalonia (INEFC). University of Barcelona (UB), Barcelona, Spain
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2
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Limited Effect of Dehydrating via Active vs. Passive Heat Stress on Plasma Volume or Osmolality, Relative to the Effect of These Stressors per Se. Nutrients 2023; 15:nu15040904. [PMID: 36839262 PMCID: PMC9959915 DOI: 10.3390/nu15040904] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 02/05/2023] [Accepted: 02/06/2023] [Indexed: 02/15/2023] Open
Abstract
The physiological, perceptual, and functional effects of dehydration may depend on how it is incurred (e.g., intense exercise releases endogenous water via glycogenolysis) but this basic notion has rarely been examined. We investigated the effects of active (exercise) heat- vs. passive heat-induced dehydration, and the kinetics of ad libitum rehydration following each method. Twelve fit participants (five females and seven males) completed four trials in randomised order: DEHydration to -3% change in body mass (∆BM) under passive or active heat stress, and EUHydration to prevent ∆BM under passive or active heat stress. In all trials, participants then sat in a temperate-controlled environment, ate a standard snack and had free access to water and sports drink during their two-hour recovery. During mild dehydration (≤2% ∆BM), active and passive heating caused comparable increases in plasma osmolality (Posm: ~4 mOsmol/kg, interaction: p = 0.138) and reductions in plasma volume (PV: ~10%, interaction: p = 0.718), but heat stress per se was the main driver of hypovolaemia. Thirst in DEHydration was comparably stimulated by active than passive heat stress (p < 0.161) and shared the same relation to Posm (r ≥ 0.744) and ∆BM (r ≥ 0.882). Following heat exposures, at 3% gross ∆BM, PV reduction was approximately twice as large from passive versus active heating (p = 0.003), whereas Posm perturbations were approximately twice as large from EUHydration versus DEHydration (p < 0.001). Rehydrating ad libitum resulted in a similar net fluid balance between passive versus active heat stress and restored PV despite the incomplete replacement of ∆BM. In conclusion, dehydrating by 2% ∆BM via passive heat stress generally did not cause larger changes to PV or Posm than via active heat stress. The heat stressors themselves caused a greater reduction in PV than dehydration did, whereas ingesting water to maintain euhydration produced large reductions in Posm in recovery and therefore appears to be of more physiological significance.
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3
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Tan XR, Low ICC, Byrne C, Wang R, Lee JKW. Assessment of dehydration using body mass changes of elite marathoners in the tropics. J Sci Med Sport 2021; 24:806-810. [DOI: 10.1016/j.jsams.2021.01.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 12/30/2020] [Accepted: 01/19/2021] [Indexed: 11/27/2022]
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4
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Toro-Campos R, Algarín C, Peirano P, Peña M, Murguia-Peniche T, Wu SS, Uauy R. Effect of feeding mode on infant growth and cognitive function: study protocol of the Chilean infant Nutrition randomized controlled Trial (ChiNuT). BMC Pediatr 2020; 20:225. [PMID: 32423392 PMCID: PMC7236373 DOI: 10.1186/s12887-020-02087-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 04/15/2020] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND A central aim for pediatric nutrition is to develop infant formula compositionally closer to human milk. Milk fat globule membranes (MFGM) have shown to have functional components that are found in human milk, suggesting that addition of bovine sources of MFGM (bMFGM) to infant formula may promote beneficial outcomes potentially helping to narrow the gap between infants who receive human breast milk or infant formula. The objective of the current study is to determine how the addition of bMFGM in infant formula and consumption in early infancy affects physical growth and brain development when compared to infants fed with a standard formula and a reference group of infants fed with mother's own milk. METHODS Single center, double-blind, and parallel randomized controlled trial. Planned participant enrollment includes: infants exclusively receiving breast milk (n = 200; human milk reference group; HM) and infants whose mothers chose to initiate exclusive infant formula feeding before 4 months of age (n = 340). The latter were randomized to receive one of two study formulas until 12 months of age: 1) cow's milk based infant formula that had docosahexaenoic (DHA) (17 mg/100 kcal) and arachidonic acid (ARA) (25 mg/100 kcal); 1.9 g protein/100 kcal; 1.2 mg Fe/100 kcal (Standard formula; SF) or 2) a similar infant formula with an added source of bovine MFGM (whey protein-lipid concentrate (Experimental formula; EF). Primary outcomes will be: 1) Physical growth (Body weight, length, and head circumference) at 730 days of age; and 2) Cognitive development (Auditory Event-Related Potential) at 730 days of age. Data will be analyzed for all participants allocated to each study feeding group. DISCUSSION The results of this study will complement the knowledge regarding addition of bMFGM in infant formula including support of healthy growth and improvement of neurodevelopmental outcomes. TRIAL REGISTRATION NCT02626143, registered on December 10th 2015.
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Affiliation(s)
- Rosario Toro-Campos
- Institute of Nutrition and Food Technology (INTA), University of Chile, Av El Libano 5524, Macul, Santiago, Chile
| | - Cecilia Algarín
- Institute of Nutrition and Food Technology (INTA), University of Chile, Av El Libano 5524, Macul, Santiago, Chile
| | - Patricio Peirano
- Institute of Nutrition and Food Technology (INTA), University of Chile, Av El Libano 5524, Macul, Santiago, Chile
| | - Marcela Peña
- Psychology Department, Pontific Catholic University, Santiago, Chile
| | | | - Steven S. Wu
- Medical Affairs, Mead Johnson Nutrition, Evansville, IN USA
| | - Ricardo Uauy
- Institute of Nutrition and Food Technology (INTA), University of Chile, Av El Libano 5524, Macul, Santiago, Chile
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5
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Hermand E, Chabert C, Hue O. Ultra-endurance events in tropical environments and countermeasures to optimize performances and health. Int J Hyperthermia 2019; 36:753-760. [PMID: 31429600 DOI: 10.1080/02656736.2019.1635718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Physical performance in a tropical environment, combining high heat and humidity, is a difficult physiological challenge that requires specific preparation. The elevated humidity of a tropical climate impairs the thermoregulatory mechanisms by limiting the rate of sweat evaporation. Hence, a proper management of whole-body temperature is required to complete an ultra-endurance event in such an environment. In these long-duration events, which can last from 8 to 20 h, held in hot and humid settings, performance is tightly linked to the ability in maintaining an optimal hydration status. Indeed, the rate of withdrawal in these longer races was associated with lower water intake, and the majority of finishers exhibited alterations in electrolyte balance (e.g., sodium). Hence, this work reviews the effects on performance of high heat and humidity in two representative ultra-endurance sports, ultramarathons and long-distance triathlons, and several countermeasures to counteract the impact of these harsh environmental stresses and maintain a high level of performance, such as hydration, cooling strategies and heat acclimation.
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Affiliation(s)
- E Hermand
- Laboratory « Adaptations au Climat Tropical, Exercice et Santé » (EA 3596 ACTES), French West Indies University , Pointe-à-Pitre , France.,Laboratory « Handicap, Activité, Vieillissement, Autonomie, Environnement » (EA 6310 HAVAE), University of Limoges , Limoges , France
| | - C Chabert
- Laboratory « Adaptations au Climat Tropical, Exercice et Santé » (EA 3596 ACTES), French West Indies University , Pointe-à-Pitre , France
| | - O Hue
- Laboratory « Adaptations au Climat Tropical, Exercice et Santé » (EA 3596 ACTES), French West Indies University , Pointe-à-Pitre , France
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6
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Chlíbková D, Žákovská A, Rosemann T, Knechtle B, Bednář J. Body Composition Changes During a 24-h Winter Mountain Running Race Under Extremely Cold Conditions. Front Physiol 2019; 10:585. [PMID: 31139095 PMCID: PMC6527803 DOI: 10.3389/fphys.2019.00585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Accepted: 04/26/2019] [Indexed: 12/20/2022] Open
Abstract
Background: To date, no study has focused on body composition characteristics and on parameters associated with skeletal muscle damage and renal function in runners participating in a 24-h winter race held under extremely cold environmental conditions (average temperature of -14.3°C). Methods: Anthropometric characteristics, plasma urea (PU), plasma creatinine (Pcr), creatine kinase (CK), plasma volume (PV) and total body water (TBW) were assessed pre- and post-race in 20 finishers (14 men and 6 women). Results: In male runners, body mass (BM) (p = 0.003) and body fat (BF) (p = 0.001) decreased [-1.1 kg (-1.4%) and -1.1 kg (-13.4%), respectively]; skeletal muscle mass (SM) and TBW remained stable (p > 0.05). In female runners, BF decreased (p = 0.036) [-1.3 kg (-7.8%)] while BM, SM and TBW remained stable (p > 0.05). The change (Δ) in BM was not related to Δ BF; however, Δ BM was related to Δ SM [r = 0.58, p = 0.007] and Δ TBW (r = 0.59, p = 0.007). Δ SM correlated with Δ TBW (r = 0.51, p = 0.021). Moreover, Δ BF was negatively associated with Δ SM (r = -0.65, p = 0.002). PV (p < 0.001), CK (p < 0.001), Pcr (p = 0.004) and PU (p < 0.001) increased and creatinine clearance (CrCl) decreased (p = 0.002). The decrease in BM was negatively related to the increase in CK (r = -0.71, p < 0.001). Δ Pcr was positively related to Δ PU (r = 0.64, p = 0.002). The decrease in CrCl was negatively associated with the increase in both PU (r = -0.72, p < 0.001) and CK (r = -0.48, p = 0.032). Conclusion: The 24-h running race under extremely cold conditions led to a significant BF decrease, whereas SM and TBW remained stable in both males and females. Nevertheless, the increase in CK, Pcr and PU was related to the damage of SM with transient impaired renal function.
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Affiliation(s)
- Daniela Chlíbková
- Centre of Sports Activities, Brno University of Technology, Brno, Czechia
| | - Alena Žákovská
- Institute of Experimental Biology, Masaryk University, Brno, Czechia
| | - Thomas Rosemann
- Institute of Primary Care, University of Zurich, Zurich, Switzerland
| | - Beat Knechtle
- Institute of Primary Care, University of Zurich, Zurich, Switzerland.,Medbase St. Gallen Am Vadianplatz, St. Gallen, Switzerland
| | - Josef Bednář
- Institute of Mathematics, Brno University of Technology, Brno, Czechia
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7
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Abstract
Ultramarathon running events and participation numbers have increased progressively over the past three decades. Besides the exertion of prolonged running with or without a loaded pack, such events are often associated with challenging topography, environmental conditions, acute transient lifestyle discomforts, and/or event-related health complications. These factors create a scenario for greater nutritional needs, while predisposing ultramarathon runners to multiple nutritional intake barriers. The current review aims to explore the physiological and nutritional demands of ultramarathon running and provide general guidance on nutritional requirements for ultramarathon training and competition, including aspects of race nutrition logistics. Research outcomes suggest that daily dietary carbohydrates (up to 12 g·kg-1·day-1) and multiple-transportable carbohydrate intake (∼90 g·hr-1 for running distances ≥3 hr) during exercise support endurance training adaptations and enhance real-time endurance performance. Whether these intake rates are tolerable during ultramarathon competition is questionable from a practical and gastrointestinal perspective. Dietary protocols, such as glycogen manipulation or low-carbohydrate high-fat diets, are currently popular among ultramarathon runners. Despite the latter dietary manipulation showing increased total fat oxidation rates during submaximal exercise, the role in enhancing ultramarathon running performance is currently not supported. Ultramarathon runners may develop varying degrees of both hypohydration and hyperhydration (with accompanying exercise-associated hyponatremia), dependent on event duration, and environmental conditions. To avoid these two extremes, euhydration can generally be maintained through "drinking to thirst." A well practiced and individualized nutrition strategy is required to optimize training and competition performance in ultramarathon running events, whether they are single stage or multistage.
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8
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Abstract
The health and performance of ultra-endurance athletes is dependent on avoidance of performance limiting hypohydration while also avoiding the potentially fatal consequences of exercise-associated hyponatremia due to overhydration. In this work, key factors related to maintaining proper hydration during ultra-endurance activities are discussed. In general, proper hydration need not be complicated and has been well demonstrated to be achieved by simply drinking to thirst and consuming a typical race diet during ultra-endurance events without need for supplemental sodium. As body mass is lost from oxidation of stored fuel, and water supporting the intravascular volume is generated from endogenous fuel oxidation and released with glycogen oxidation, the commonly promoted hydration guidelines of avoiding body mass losses of >2% can result in overhydration during ultra-endurance activities. Thus, some body mass loss should occur during prolonged exercise, and appropriate hydration can be maintained by drinking to the dictates of thirst.
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9
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Hoffman MD, Goulet EDB, Maughan RJ. Considerations in the Use of Body Mass Change to Estimate Change in Hydration Status During a 161-Kilometer Ultramarathon Running Competition. Sports Med 2018; 48:243-250. [PMID: 28895063 DOI: 10.1007/s40279-017-0782-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydration guidelines found in the scientific and popular literature typically advise that body mass losses beyond 2% should be avoided during exercise. In this work, we demonstrate that these guidelines are not applicable to prolonged exercise of several hours where body mass loss does not reflect an equivalent loss of body water due to the effects of body mass change from substrate use, release of water bound with muscle and liver glycogen, and production of water during substrate metabolism. These effects on the body mass loss required to maintain body water balance are shown for a 161-km mountain ultramarathon running competition participant utilizing published data for the total energy cost, exogenous energy consumption and percentage from each fuel source, average participant body mass, and the extent of soft tissue fluid accumulation during an ultramarathon. We assumed that total energy derived from protein ranges from 5 to 10%, all exogenous energy is used to support the energy cost of the race, glycogen utilization ranges from 300 to 500 g, water linked with glycogen ranges from 1 to 3 g per g of glycogen, and the mass of the bladder and gastrointestinal tract is unchanged from pre-race to post-race body mass measurements. These calculations show that the average participant of 68.8 kg must lose 1.9-5.0% body mass to maintain the water supporting body water balance while also avoiding overhydration. Future hydration guidelines should consider these findings so that the proper hydration message is conveyed to those who participate in prolonged exercise.
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Affiliation(s)
- Martin D Hoffman
- Department of Physical Medicine and Rehabilitation, Department of Veterans Affairs, Northern California Health Care System, 10535 Hospital Way, Sacramento, CA, 95655-1200, USA. .,Department of Physical Medicine and Rehabilitation, University of California Davis Medical Center, Sacramento, CA, USA. .,Ultra Sports Science Foundation, El Dorado Hills, CA, USA.
| | - Eric D B Goulet
- Research Centre on Aging and Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC, Canada
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10
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Ad libitum drinking adequately supports hydration during 2 h of running in different ambient temperatures. Eur J Appl Physiol 2018; 118:2687-2697. [PMID: 30267225 DOI: 10.1007/s00421-018-3996-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 09/18/2018] [Indexed: 01/06/2023]
Abstract
PURPOSE To examine if ad libitum drinking will adequately support hydration during exertional heat stress. METHODS Ten endurance-trained runners ran for 2 h at 60% of maximum oxygen uptake under different conditions. Participants drank water ad libitum during separate trials at mean ambient temperatures of 22 °C, 30 °C and 35 °C. Participants also completed three trials at a mean ambient temperature of 35 °C while drinking water ad libitum in all trials, and with consumption of programmed glucose or whey protein hydrolysate solutions to maintain euhydration in two of these trials. Heart rate, oxygen uptake, rectal temperature, perceived effort, and thermal sensation were monitored, and nude body mass, hemoglobin, hematocrit, and plasma osmolality were measured before and after exercise. Water and mass balance equations were used to calculate hydration-related variables. RESULTS Participants adjusted their ad libitum water intake so that the same decrease in body mass (1.1-1.2 kg) and same decrease in body water (0.8-0.9 kg) were observed across the range of ambient temperatures which yielded significant differences (p < .001) in sweat loss. Overall, water intake and total water gain replaced 57% and 66% of the water loss, respectively. The loss in body mass and body water associated with ad libitum drinking resulted in no alteration in physiological and psychophysiological variables compared with the condition when hydration was nearly fully maintained (0.3 L body water deficit) relative to pre-exercise status from programmed drinking. CONCLUSIONS Ad libitum drinking is an appropriate strategy for supporting hydration during running for 2 h duration under hot conditions.
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11
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Goulet EDB. Comment on "Drinking Strategies: Planned Drinking Versus Drinking to Thirst''. Sports Med 2018; 49:631-633. [PMID: 30094801 DOI: 10.1007/s40279-018-0973-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Eric D B Goulet
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC, Canada. .,Research Centre on Aging, University of Sherbrooke, Sherbrooke, QC, Canada. .,Performance, Hydration and Thermoregulation Laboratory, University of Sherbrooke, 2500 boul. de l'Université, Sherbrooke, QC, J1K 2R1, Canada.
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12
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Hoffman MD, Stellingwerff T, Costa RJS. Considerations for ultra-endurance activities: part 2 - hydration. Res Sports Med 2018; 27:182-194. [PMID: 30056755 DOI: 10.1080/15438627.2018.1502189] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
It is not unusual for those participating in ultra-endurance (> 4 hr) events to develop varying degrees of either hypohydration or hyperhydration. Yet, it is important for ultra-endurance athletes to avoid the performance limiting and potentially fatal consequences of these conditions. During short periods of exercise (< 1 hr), trivial effects on the relationship between body mass change and hydration status result from body mass loss due to oxidation of endogenous fuel stores, and water supporting the intravascular volume being generated from endogenous fuel oxidation and released with glycogen oxidation. However, these effects have meaningful implications during prolonged exercise. In fact, body mass loses well over 2% may be required during some ultra-endurance activities to avoid hyperhydration. Therefore, the typical hydration guidelines to avoid more than 2% body mass loss do not apply in ultra-endurance activities and can potentially result in hyperhydration. Fortunately, achieving the balance of proper hydration during ultra-endurance activities need not be complicated and has been well demonstrated to generally be achieved by simply drinking to thirst and avoiding excessive sodium supplementation with intention of replacing all sodium losses during the exercise.
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Affiliation(s)
- Martin D Hoffman
- a Physical Medicine and Rehabilitation Service, Department of Veterans Affairs , Northern California Health Care System , Sacramento , CA , USA.,b Department of Physical Medicine and Rehabilitation , University of California Davis Medical Center , Sacramento , CA , USA.,c Ultra Sports Science Foundation , El Dorado Hills , CA , USA
| | | | - Ricardo J S Costa
- e Department of Nutrition Dietetics and Food , Monash University , Notting Hill , Victoria , Australia
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13
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Chlíbková D, Nikolaidis PT, Rosemann T, Knechtle B, Bednář J. Fluid Metabolism in Athletes Running Seven Marathons in Seven Consecutive Days. Front Physiol 2018; 9:91. [PMID: 29483882 PMCID: PMC5816349 DOI: 10.3389/fphys.2018.00091] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 01/26/2018] [Indexed: 11/17/2022] Open
Abstract
Purpose: Hypohydration and hyperhydration are significant disorders of fluid metabolism in endurance performance; however, little relevant data exist regarding multi-stage endurance activities. The aim of the present study was to examine the effect of running seven marathons in 7 consecutive days on selected anthropometric, hematological and biochemical characteristics with an emphasis on hydration status. Methods: Participants included 6 women and 20 men (age 42.6 ± 6.2 years). Data was collected before day 1 (B1) and after day 1 (A1), 4 (A4), and 7 (A7). Results: The average marathon race time was 4:44 h:min (ranging from 3:09 – 6:19 h:min). Plasma sodium, plasma potassium and urine sodium were maintained during the race. Body mass (p < 0.001, η2 = 0.501), body fat (p < 0.001, η2 = 0.572) and hematocrit (p < 0.001, η2 = 0.358) decreased. Plasma osmolality (Posm) (p < 0.001, η2 = 0.416), urine osmolality (Uosm) (p < 0.001, η2 = 0.465), urine potassium (p < 0.001, η2 = 0.507), urine specific gravity (Usg) (p < 0.001, η2 = 0.540), plasma urea (PUN) (p < 0.001, η2 = 0.586), urine urea (UUN) (p < 0.001, η2 = 0.532) and transtubular potassium gradient (p < 0.001, η2 = 0.560) increased at A1, A4, and A7 vs. B1. Posm correlated with PUN at A1 (r = 0.59, p = 0.001) and A4 (r = 0.58, p = 0.002). The reported post-race fluid intake was 0.5 ± 0.2 L/h and it correlated negatively with plasma [Na+] (r = −0.42, p = 0.007) at A4 and (r = −0.50, p = 0.009) at A7. Uosm was associated with UUN at A1 (r = 0.80, p < 0.001), at A4 (r = 0.81, p < 0.001) and at A7 (r = 0.86, p < 0.001) and with Usg (r = 0.71, p < 0.001) at A1, (r = 0.52, p = 0.006) at A4 and (r = 0.46, p = 0.02) at A7. Conclusions: Despite the decrease in body mass, fluid and electrolyte balance was maintained with no decrease in plasma volume after running seven marathons in seven consecutive days. Current findings support the hypothesis that body mass changes do not reflect changes in the hydration status during prolonged exercise.
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Affiliation(s)
- Daniela Chlíbková
- Centre of Sports Activities, Brno University of Technology, Brno, Czechia
| | | | - Thomas Rosemann
- Institute of Primary Care, University of Zurich, Zurich, Switzerland
| | - Beat Knechtle
- Institute of Primary Care, University of Zurich, Zurich, Switzerland.,Medbase St. Gallen Am Vadianplatz, St. Gallen, Switzerland
| | - Josef Bednář
- Faculty of Mechanical Engineering, Brno University of Technology, Brno, Czechia
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14
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Hoffman MD, Cotter JD, Goulet ÉD, Laursen PB. REBUTTAL from "Yes". Wilderness Environ Med 2017; 27:198-200. [PMID: 27291701 DOI: 10.1016/j.wem.2016.04.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 04/10/2016] [Accepted: 04/11/2016] [Indexed: 12/30/2022]
Affiliation(s)
- Martin D Hoffman
- Department of Physical Medicine & Rehabilitation, Department of Veterans Affairs, Northern California Health Care System, and University of California Davis Medical Center, Sacramento, CA.
| | - James D Cotter
- Exercise and Environmental Physiology, School of Physical Education, Sport and Exercise Sciences, Division of Sciences, University of Otago, Dunedin, New Zealand(Dr Cotter)?>
| | - Éric D Goulet
- Research Centre on Aging, Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC, Quebec, Canada
| | - Paul B Laursen
- High Performance Sport New Zealand, and Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Aukland, Auckland, New Zealand
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Hoffman MD, Cotter JD, Goulet ÉD, Laursen PB. VIEW: Is Drinking to Thirst Adequate to Appropriately Maintain Hydration Status During Prolonged Endurance Exercise? Yes. Wilderness Environ Med 2017; 27:192-5. [PMID: 27291699 DOI: 10.1016/j.wem.2016.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 03/03/2016] [Accepted: 03/09/2016] [Indexed: 10/21/2022]
Affiliation(s)
- Martin D Hoffman
- Department of Physical Medicine & Rehabilitation Department of Veterans Affairs, Northern California Health Care System, and University of California Davis Medical Center, Sacramento, CA, USA (Dr Hoffman)
| | - James D Cotter
- Exercise and Environmental Physiology, School of Physical Education, Sport and Exercise Sciences Division of Sciences, University of Otago, Dunedin New Zealand (Dr Cotter)
| | - Éric D Goulet
- Research Centre on Aging, Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC Canada (Dr Goulet)
| | - Paul B Laursen
- High Performance Sport New Zealand, and Sports Performance Research Institute New Zealand (SPRINZ) Auckland University of Technology, Auckland New Zealand (Dr Laursen)
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Abstract
OBJECTIVE Because inappropriate recommendations about hydration during exercise appear widespread and potentially dangerous, we assessed the quality of a sampling of information currently available to the public on the Internet. METHODS Internet searches using the Google search engine were conducted using the terms "hydration," "hydration guidelines," "drinking fluids" and "drinking guidelines" combined with "and exercise." From the first 50 websites for each search phrase, duplicates were removed yielding 141 unique websites that were categorized by source and examined for specific hydration related information and recommendations. RESULTS Correct endorsement was as follows (reported as percent endorsing the concept relative to the number of websites addressing the issue): some weight loss should be expected during exercise (69.5% of 95), fluid consumption during exercise should be based upon thirst (7.3% of 110), electrolyte intake is not generally necessary during exercise (10.4% of 106), dehydration is not generally a cause of heat illness (3.4% of 58) or exercise-associated muscle cramping (2.4% of 42), exercise-associated muscle cramping is not generally related to electrolyte loss (0.0% of 16), and overhydration is a risk for hyponatremia (100.0% of 61). Comparison of website information from medical or scientific sources with that from other sources revealed no differences (p = 0.4 to 1.0) in the frequency of correct endorsement of the examined criteria. CONCLUSION Prevalent misinformation on the Internet about hydration needs during exercise and the contribution of hydration status to the development of heat illness and muscle cramping fosters overhydration. In general, those websites that should be most trusted by the public were no better than other websites at providing accurate information, and the potential risk of hyponatremia from overhydration was noted by less than half the websites. Since deaths from exercise-associated hyponatremia should be preventable through avoidance of overhydration, dissemination of a more appropriate hydration message is important.
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Affiliation(s)
- Martin D Hoffman
- a Department of Physical Medicine & Rehabilitation, Department of Veterans Affairs , Northern California Health Care System, University of California Davis Medical Center , Sacramento , CA , USA
| | - Theodore L Bross
- b Wright State University, Boonshoft School of Medicine , Dayton , OH , USA
| | - R Tyler Hamilton
- c The School of Education and Behavioral Studies , Palm Beach Atlantic University , West Palm Beach , FL , USA
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Hoffman MD, Stuempfle KJ. Is Sodium Supplementation Necessary to Avoid Dehydration During Prolonged Exercise in the Heat? J Strength Cond Res 2016; 30:615-20. [PMID: 26907835 DOI: 10.1519/jsc.0000000000001138] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The primary purpose of this work was to gain further insight into the need for sodium supplementation for maintenance of appropriate hydration during prolonged exercise under hot conditions. Participants of a 161-km ultramarathon (ambient temperature reaching 39° C) underwent body weight measurements immediately before, during, and after the race, and completed a postrace questionnaire about supplemental sodium intake and drinking strategies during 4 race segments. The postrace questionnaire was completed by 233 (78.7%) race finishers. Significant direct relationships were found for percentage weight change during the race with intake rate (r = 0.18, p = 0.0058) and total amount (r = 0.24, p = 0.0002) of sodium in supplements. Comparing those using no sodium supplements throughout the race (n = 15) with those using sodium supplements each race segment (n = 138), body weight change across the course showed significant group (p = 0.022), course location (p < 0.0001), and interaction (p = 0.0098) effects. Posttests revealed greater weight loss at 90 km (p = 0.016, -3.2 ± 1.6% vs. -2.2 ± 1.5%, mean ± SD) and the finish (p = 0.014, -3.2 ± 1.5% vs. -1.9 ± 1.9%) for those using no sodium supplements compared with those using sodium supplements each segment. Six runners who used no sodium supplements, drank to thirst, and only drank water or a mixture of mostly water with some electrolyte-containing drink finished with mean weight change of -3.4%. Although the use of supplemental sodium enhanced body weight maintenance, those not using sodium supplements maintained a more appropriate weight than those consistently using sodium supplements. Therefore, we conclude that the supplemental sodium is unnecessary to maintain appropriate hydration during prolonged exercise in the heat.
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Affiliation(s)
- Martin D Hoffman
- 1Department of Physical Medicine & Rehabilitation, Department of Veterans Affairs, Northern California Health Care System, and University of California Davis Medical Center, Sacramento, California; and2Health Sciences Department, Gettysburg College, Gettysburg, Pennsylvania
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Cutrufello PT, Dixon CB, Zavorsky GS. Hydration assessment among marathoners using urine specific gravity and bioelectrical impedance analysis. Res Sports Med 2016; 24:234-42. [PMID: 27373703 DOI: 10.1080/15438627.2016.1202831] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The present study examined the relationship between urine specific gravity (Usg), body mass (BM) and bioelectrical impedance determined variables [total body water (TBW), per cent TBW and impedance values] before and after a marathon (n = 25 men; 10 women). A significant reduction in BM (pre: 71.2 ± 12.4 kg; post: 69.6 ± 12.0 kg; p < 0.001) and an increase in Usg (pre: 1.009 ± 0.007; post: 1.018 ± 0.009; p < 0.001) was observed post-race. TBW was not significantly decreased (pre: 42.7 ± 8.0 kg; post: 42.4 ± 7.7 kg) while per cent TBW significantly increased post-race (pre: 60.0 ± 3.9%; post: 60.8 ± 3.8%; p < 0.001). Impedance values were significantly greater post-race (pre: 3288 ± 482; post: 3416 ± 492 Ω; p < 0.001). There was no correlation between the change in Usg and the change in BM or any of the bioelectrical impedance determined variables. On average, BM, Usg and impedance values appear to express changes in hydration; however, the observed changes among these variables for a given individual appear to be inconsistent with one another.
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Affiliation(s)
- Paul T Cutrufello
- a Exercise Science and Sport , The University of Scranton , Scranton , PA , USA
| | - Curt B Dixon
- b Health Sciences Dept , Lock Haven University , Lock Haven , PA , USA
| | - Gerald S Zavorsky
- c Department of Health and Sports Sciences , University of Louisville , Louisville , KY , USA
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Valentino TR, Stuempfle KJ, Kern M, Hoffman MD. The influence of hydration state on thermoregulation during a 161-km ultramarathon. Res Sports Med 2016; 24:212-21. [PMID: 27258701 DOI: 10.1080/15438627.2016.1191491] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
It is advised that individuals should avoid losing >2% of their body mass during exercise in order to prevent hyperthermia. This study sought to assess whether a loss of >2% body mass leads to elevations in core temperature during an ultramarathon. Thirty runners agreed to take part in the study. Body mass and core temperature were measured at the start, at three locations during the race and the finish. Core temperature was not correlated with percent body mass change (p = 0.19) or finish time (p = 0.11). Percent body mass change was directly associated with finish time (r = 0.58, p < 0.01), such that the fastest runners lost the most mass (~3.5-4.0%). It appears that a loss of >3% body mass does not contribute to rises in core temperature. An emphasis on fluid replacement for body mass losses of this magnitude during prolonged exercise is not justified as a preventative measure for heat-related illnesses.
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Affiliation(s)
- Taylor R Valentino
- a Department of Kinesiology , San Francisco State University , San Francisco , CA , USA
| | | | - Marialice Kern
- a Department of Kinesiology , San Francisco State University , San Francisco , CA , USA
| | - Martin D Hoffman
- c Department of Physical Medicine & Rehabilitation, Department of Veterans Affairs , Northern California Health Care System, and University of California Davis Medical Center , Sacramento , CA , USA.,d Department of Physical Rehabilitation , Sarcomento VA Medical Center , Sacromento , CA , USA
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Armstrong LE, Johnson EC, Ganio MS, Judelson DA, Vingren JL, Kupchak BR, Kunces LJ, Muñoz CX, McKenzie AL, Williamson KH. Effective body water and body mass changes during summer ultra-endurance road cycling. J Sports Sci 2014; 33:125-35. [PMID: 24992367 DOI: 10.1080/02640414.2014.932918] [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: 10/25/2022]
Abstract
Because body mass change (ΔMb) does not represent all water losses and gains, the present field investigation determined if (a) ΔMb equalled the net effective body water change during ultra-endurance exercise and (b) ground speed and exercise duration influenced these variables. Thirty-two male cyclists (age range, 35-52 years) completed a 164-km event in a hot environment, were retrospectively triplet matched and placed into one of three groups based on exercise duration (4.8, 6.3, 9.6 h). Net effective body water loss was computed from measurements (body mass, total fluid intake and urine excreted) and calculations (water evolved and mass loss due to substrate oxidation, solid food mass and sweat loss), including (ΔEBWgly) and excluding (ΔEBW) water bound to glycogen. With all cyclists combined, the mean ΔMb (i.e. loss) was greater than that of ΔEBWgly by 1200 ± 200 g (P = 1.4 × 10(-18)), was similar to ΔEBW (difference, 0 ± 200 g; P = .21) and was strongly correlated with both (R(2) = .98). Analysis of equivalence indicated that ΔMb was not equivalent to ΔEBWgly, but was equivalent to ΔEBW. Due to measurement complexity, we concluded that (a) athletes will not calculate the effective body water calculations routinely and (b) body mass change remains a useful field-expedient estimate of net effective body water change.
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Affiliation(s)
- Lawrence E Armstrong
- a Department of Kinesiology, Human Performance Laboratory , University of Connecticut , Storrs , CT , USA
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Analysis of weight change and Borg rating of perceived exertion as measurements of runner health and safety during a 6-day, multistage, remote ultramarathon. Clin J Sport Med 2014; 24:245-50. [PMID: 24284951 DOI: 10.1097/jsm.0000000000000019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine the feasibility of using weight change and Borg score as tools for monitoring runner health and safety during a multistage, remote ultramarathon. DESIGN Observational cohort study of feasibility on nonblinded event participants. SETTING Six-day, multistage, remote ultramarathon in Utah. PARTICIPANTS Twenty-seven athletes in the 2012 Desert R.A.T.S. (Race Across the Sand) ultramarathon. ASSESSMENT OF RISK FACTORS Participant weight, health conditions that limited race participation, such as fatigue or exhaustion, and Borg score were reviewed. MAIN OUTCOME MEASURES Inability to complete a stage of the race (Did Not Finish status) or development of a clinically significant health condition during the race. Potential prognostic risk factors, such as a high Borg score and weight loss, were analyzed. RESULTS An overall decrease in weight was observed over the course of the event. Median percent weight changes were losses of 2.96% (day 1), 7.42% (day 2), 2.21% (day 4), and 3.35% (day 6). There was no statistically significant difference in percent weight change between the 14 runners who finished the race and the 13 runners who did not finish the race (U = 73; z = 0.189; P = 0.85). Runners' ability to complete the race was related to the development of adverse health conditions (P = 0.004). Median Borg scores reported were 15 (day 1), 17 (day 2), 13 (day 3), 16 (day 4), and 15 (day 6). Only 2 racers who finished the entire event without adverse events ever gave a Borg score of ≥ 18. CONCLUSIONS The feasibility of weight change as a tool for monitoring runner health and safety in this setting is limited, but the Borg rating of perceived exertion warrants further study as a potential field expedient tool for monitoring runner health and safety during a multiday, remote ultramarathon.
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Chlíbková D, Knechtle B, Rosemann T, Žákovská A, Tomášková I. The prevalence of exercise-associated hyponatremia in 24-hour ultra-mountain bikers, 24-hour ultra-runners and multi-stage ultra-mountain bikers in the Czech Republic. J Int Soc Sports Nutr 2014; 11:3. [PMID: 24512517 PMCID: PMC3929155 DOI: 10.1186/1550-2783-11-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 02/05/2014] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND To assess the prevalence of exercise-associated hyponatremia (EAH) in two 24-hour mountain bike (MTB) (R1,R2), one 24-hour running (R3) and one multi-stage MTB (R4) races held in the Czech Republic in a cluster of four cross-sectional studies. METHODS In 27 ultra-mountain bikers (ultra-MTBers), 12 ultra-runners, and 14 multi-stage MTBers, fluid intake, changes (Δ) in body mass, hematocrit, plasma volume, plasma [Na+], plasma [K+], plasma osmolality, urine [Na+], urine [K+], urine specific gravity, urine osmolality, K+/Na+ ratio in urine, transtubular potassium gradient and glomerular filtration rate were measured and calculated. The use of non-steroidal anti-inflammatory drugs and symptoms of EAH were recorded using post-race questionnaires. RESULTS Of the 53 finishers, three (5.7%) developed post-race EAH, thereof one (3.7%) ultra-MTBer, one (8.3%) ultra-runner and one (7.1%) multi-stage MTBer. Plasma [Na+] decreased significantly (p < 0.001) only in R4. Urine osmolality (R1, R3, R4 p < 0.001; R2 p < 0.05) and glomerular filtration rate (p < 0.001) increased, and body mass decreased in all races (p < 0.05). Δ body mass was inversely related to the number of kilometers achieved (p < 0.001) in R2 where better ultra-MTBers tended to lose more weight. Δ body mass (p < 0.001) and %Δ body mass (p = 0.05) were positively related to lower post-race plasma [Na+] in R3 that was associated with increased loss in body mass. Fluid intake was positively related to race performance in R1 and R2 (R1: p = 0.04; R2: p = 0.01) where ultra-MTBers in R1 and R2 who drank more finished ahead of those who drank less. Post-race plasma [Na+] was negatively associated with race performance in ultra-MTBers in R2 (p < 0.05), similarly ultra-runners in R3 (p < 0.05) where finishers with more kilometres had lower post-race plasma [Na+]. CONCLUSIONS The prevalence of EAH in the Czech Republic was no higher compared to existing reports on ultra-endurance athletes in other countries. Lower plasma [Na+] and development of EAH may be attributed to overdrinking, a pituitary secretion of vasopressin, an impaired mobilization of osmotically inactive sodium stores, and/or an inappropriate inactivation of osmotically active sodium.
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Affiliation(s)
- Daniela Chlíbková
- Centre of Sports Activities, Brno University of Technology, Brno, Czech Republic
| | - Beat Knechtle
- Institute of General Practise and for Health Services Research, University of Zurich, Zurich, Switzerland
- Facharzt FMH für Allgemeinmedizin, Gesundheitszentrum St. Gallen, Vadianstrasse 26, 9001 St. Gallen, Switzerland
| | - Thomas Rosemann
- Institute of General Practise and for Health Services Research, University of Zurich, Zurich, Switzerland
| | - Alena Žákovská
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Ivana Tomášková
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czech Republic
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Abstract
OBJECTIVE To examine the relationships between changes in static prestage and poststage measures of commonly used hematological and urinary markers of hydration status and body mass (BM) in participants in a 3-day trail run. DESIGN Descriptive field study. SETTING Three Cranes Challenge trail run, South Africa. PARTICIPANTS Twenty (6 men and 14 women) amateur runners. INTERVENTIONS In stage 1 (S1), 29.3 km and 37.9 km in stage 2 (S2), and 27.8 km in stage 3 (S3). MAIN OUTCOME MEASURES Prestage and poststage individual changes in serum osmolality (S osm), serum sodium (s[Na]), plasma volume (PV), urine osmolality (U osm), urine specific gravity (U sg), and BM. RESULTS Consistently, mild environmental conditions were experienced on the 3 days of the race (ambient temperature range, 11.5-22.8°C). Mean S osm increased by 5 ± 6, 7 ± 9, and 3 ± 4 mOsm/kg during S1, S2, and S3, respectively, and returned to baseline pre-S2 and pre-S3. The correlation between individual prestage and poststage changes in S osm, Uosm, and U sg (n = 60) were nonsignificant (P > 0.05; r = 0.0047, r = 0.0074). There was a significant, but relatively low correlation between changes in S osm and percentage reduction in BM (r = 0.35; P < 0.01) and prechange and postchange in s[Na] (r = 0.45; P < 0.001). CONCLUSIONS Serum osmality values confirm appropriate interstage rehydration. Changes in U osm, U sg, BM, s[Na+], and PV are not closely related to changes in S osm as markers of hydration assessment in multiday events in which single static measures of hydration status are required. These measures of hydration station status are therefore not recommended in this field setting.
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Chen JYF, Quirt J, Lee KJ. Proposed new mechanism for food and exercise induced anaphylaxis based on case studies. Allergy Asthma Clin Immunol 2013; 9:11. [PMID: 23509907 PMCID: PMC3608993 DOI: 10.1186/1710-1492-9-11] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 02/15/2013] [Indexed: 11/10/2022] Open
Abstract
We present two cases of food and exercise-induced anaphylaxis (FEIA) in patients with a diagnosis of oral allergy syndrome (OAS) to the implicated foods. Patient A had FEIA attributed to fresh coriander and tomato and Patient B to fresh celery. These food allergens have been implicated in OAS and have structural antigenic similarity to that of birch and/or grass. Both patients' allergies were confirmed by fresh skin prick tests. In both cases, strenuous exercise was antecedent to the systemic anaphylaxis reaction and subsequent ingestion without exercise produced only local symptoms of perioral pruritus. We review the current proposed mechanisms for food and exercise induced anaphylaxis to oral allergens and propose a novel and more biologically plausible mechanism. We hypothesize that the inhibitory effects of exercise on gastric acid secretion decreases the digestion of oral allergens and preserves structural integrity, thereby allowing continued systemic absorption of the allergen whether it be profilins, lipid transfer proteins, or other antigenic determinants.
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Affiliation(s)
- Jennifer Yan Fei Chen
- Division of Allergy and Clinical Immunology, St, Michael's Hospital, University of Toronto, Toronto, ON, Canada.
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The effect of physiology and hydration beliefs on race behavior and postrace sodium in 161-km ultramarathon finishers. Int J Sports Physiol Perform 2013; 8:536-41. [PMID: 23412802 DOI: 10.1123/ijspp.8.5.536] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
PURPOSE To determine if beliefs about physiology and rehydration affect ultramarathon runners' hydration behaviors or if these beliefs increase the risk for exercise-associated hyponatremia (EAH). METHODS Participants of the 2011 161-km Western States Endurance Run completed a prerace questionnaire, prerace and postrace body-mass measurements, and postrace assessment of serum sodium ([Na⁺]). RESULTS Of 310 finishers, 309 (99.7%) completed the prerace questionnaire and 207 (67%) underwent postrace blood studies. Twelve (5.8%) finishers had asymptomatic EAH ([Na⁺] range 131-134 mmol/L). The most common hydration plan (43.1%) was drinking according to schedule, and these runners did so to replace fluid lost when sweating (100%) and to avoid dehydration (81.2%). Prerace drinking plan was not associated with postrace [Na⁺] or the development of postrace hyponatremia. There also were no group differences between those with and those without EAH for any other variables including planned energy intake or knowledge of fluid balance. Runners not planning to drink to thirst trended toward more influence from advertisements (P = .056) and were significantly more influenced by scientific organizations (P = .043) than runners with other drinking plans. Finally, runners who believe that EAH is caused by excessive drinking adopted a lower-volume drinking plan (P = .005), while runners who believe that EAH is caused by sodium loss via sweating reported more common use of sodium supplementation during the race (P = .017). CONCLUSIONS Beliefs regarding the causes of EAH alter race behaviors including drinking plan and sodium supplementation but do not appear to affect the likelihood of developing EAH during a 161-km ultramarathon.
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Meyer M, Knechtle B, Bürge J, Knechtle P, Mrazek C, Wirth A, Ellenrieder B, Rüst CA, Rosemann T. Ad libitum fluid intake leads to no leg swelling in male Ironman triathletes - an observational field study. J Int Soc Sports Nutr 2012; 9:40. [PMID: 22937792 PMCID: PMC3524467 DOI: 10.1186/1550-2783-9-40] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 08/30/2012] [Indexed: 11/10/2022] Open
Abstract
UNLABELLED BACKGROUND An association between fluid intake and limb swelling has been described for 100-km ultra-marathoners. We investigated a potential development of peripheral oedemata in Ironman triathletes competing over 3.8 km swimming, 180 km cycling and 42.2 km running. METHODS In 15 male Ironman triathletes, fluid intake, changes in body mass, fat mass, skeletal muscle mass, limb volumes and skinfold thickness were measured. Changes in renal function, parameters of skeletal muscle damage, hematologic parameters and osmolality in both serum and urine were determined. Skinfold thicknesses at hands and feet were measured using LIPOMETER® and changes of limb volumes were measured using plethysmography. RESULTS The athletes consumed a total of 8.6 ± 4.4 L of fluids, equal to 0.79 ± 0.43 L/h. Body mass, skeletal muscle mass and the volume of the lower leg decreased (p <0.05), fat mass, skinfold thicknesses and the volume of the arm remained unchanged (p >0.05). The decrease in skeletal muscle mass was associated with the decrease in body mass (p <0.05). The decrease in the lower leg volume was unrelated to fluid intake (p >0.05). Haemoglobin, haematocrit and serum sodium remained unchanged (p >0.05). Osmolality in serum and urine increased (p <0.05). The change in body mass was related to post-race serum sodium concentration ([Na+]) (r = -0.52, p <0.05) and post-race serum osmolality (r = -0.60, p <0.05). CONCLUSIONS In these Ironman triathletes, ad libitum fluid intake maintained plasma [Na+] and plasma osmolality and led to no peripheral oedemata. The volume of the lower leg decreased and the decrease was unrelated to fluid intake. Future studies may investigate ultra-triathletes competing in a Triple Iron triathlon over 11.4 km swimming, 540 km cycling and 126.6 km running to find an association between fluid intake and the development of peripheral oedemata.
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Affiliation(s)
- Michael Meyer
- Institute of Primary Care and Health Services Research, University of Zurich, Zurich, Switzerland.
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Knechtle B, Knechtle P, Wirth A, Alexander Rüst C, Rosemann T. A faster running speed is associated with a greater body weight loss in 100-km ultra-marathoners. J Sports Sci 2012; 30:1131-40. [PMID: 22668199 DOI: 10.1080/02640414.2012.692479] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
In 219 recreational male runners, we investigated changes in body mass, total body water, haematocrit, plasma sodium concentration ([Na(+)]), and urine specific gravity as well as fluid intake during a 100-km ultra-marathon. The athletes lost 1.9 kg (s = 1.4) of body mass, equal to 2.5% (s = 1.8) of body mass (P < 0.001), 0.7 kg (s = 1.0) of predicted skeletal muscle mass (P < 0.001), 0.2 kg (s = 1.3) of predicted fat mass (P < 0.05), and 0.9 L (s = 1.6) of predicted total body water (P < 0.001). Haematocrit decreased (P < 0.001), urine specific gravity (P < 0.001), plasma volume (P < 0.05), and plasma [Na(+)] (P < 0.05) all increased. Change in body mass was related to running speed (r = -0.16, P < 0.05), change in plasma volume was associated with change in plasma [Na(+)] (r = -0.28, P < 0.0001), and change in body mass was related to both change in plasma [Na(+)] (r = -0.36) and change in plasma volume (r = 0.31) (P < 0.0001). The athletes consumed 0.65 L (s = 0.27) fluid per hour. Fluid intake was related to both running speed (r = 0.42, P < 0.0001) and change in body mass (r = 0.23, P = 0.0006), but not post-race plasma [Na(+)] or change in plasma [Na(+)] (P > 0.05). In conclusion, faster runners lost more body mass, runners lost more body mass when they drank less fluid, and faster runners drank more fluid than slower runners.
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Affiliation(s)
- Beat Knechtle
- Facharzt FMH für Allgemeinmedizin, St. Gallen, Switzerland.
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Weitkunat T, Knechtle B, Knechtle P, Rüst CA, Rosemann T. Body composition and hydration status changes in male and female open-water swimmers during an ultra-endurance event. J Sports Sci 2012; 30:1003-13. [PMID: 22554315 DOI: 10.1080/02640414.2012.682083] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Body mass changes during ultra-endurance performances have been described for running, cycling and for swimming in a heated pool. The present field study of 20 male and 11 female open-water swimmers investigated the changes in body composition and hydration status during an ultra-endurance event. Body mass, both estimated fat mass and skeletal muscle mass, haematocrit, plasma sodium concentration ([Na+]) and urine specific gravity were determined. Energy intake, energy expenditure and fluid intake were estimated. Males experienced significant reductions in body mass (-0.5 %) and skeletal muscle mass (-1.1 %) (P < 0.05) during the race compared to females who showed no significant changes with regard to these variables (P > 0.05). Changes in percent body fat, fat mass, and fat-free mass were heterogeneous and did not reach statistical significance (P > 0.05) between gender groups. Fluid intake relative to plasma volume was higher in females than in males during the ultra-endurance event. Compared to males, females' average increase in haematocrit was 3.3 percentage points (pp) higher, urine specific gravity decrease 0.1 pp smaller, and plasma [Na+] 1.3 pp higher. The observed patterns of fluid intake, changes in plasma volume, urine specific gravity, and plasma [Na+] suggest that, particularly in females, a combination of fluid shift from blood vessels to interstitial tissue, facilitated by skeletal muscle damage, as well as exercise-associated hyponatremia had occurred. To summarise, changes in body composition and hydration status are different in male compared to female open-water ultra-endurance swimmers.
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Affiliation(s)
- Tim Weitkunat
- Institute of General Practice and for Health Services Research, University of Zurich, Zurich, Switzerland
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Cejka C, Knechtle B, Knechtle P, Rüst CA, Rosemann T. An increased fluid intake leads to feet swelling in 100-km ultra-marathoners - an observational field study. J Int Soc Sports Nutr 2012; 9:11. [PMID: 22472466 PMCID: PMC3366912 DOI: 10.1186/1550-2783-9-11] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 04/03/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND An association between fluid intake and changes in volumes of the upper and lower limb has been described in 100-km ultra-marathoners. The purpose of the present study was (i) to investigate the association between fluid intake and a potential development of peripheral oedemas leading to an increase of the feet volume in 100-km ultra-marathoners and (ii) to evaluate a possible association between the changes in plasma sodium concentration ([Na+]) and changes in feet volume. METHODS In seventy-six 100-km ultra-marathoners, body mass, plasma [Na+], haematocrit and urine specific gravity were determined pre- and post-race. Fluid intake and the changes of volume of the feet were measured where the changes of volume of the feet were estimated using plethysmography. RESULTS Body mass decreased by 1.8 kg (2.4%) (p < 0.0001); plasma [Na+] increased by 1.2% (p < 0.0001). Haematocrit decreased (p = 0.0005). The volume of the feet remained unchanged (p > 0.05). Plasma volume and urine specific gravity increased (p < 0.0001). Fluid intake was positively related to the change in the volume of the feet (r = 0.54, p < 0.0001) and negatively to post-race plasma [Na+] (r = -0.28, p = 0.0142). Running speed was negatively related to both fluid intake (r = -0.33, p = 0.0036) and the change in feet volume (r = -0.23, p = 0.0236). The change in the volume of the feet was negatively related to the change in plasma [Na+] (r = -0.26, p = 0.0227). The change in body mass was negatively related to both post-race plasma [Na+] (r = -0.28, p = 0.0129) and running speed (r = -0.34, p = 0.0028). CONCLUSIONS An increase in feet volume after a 100-km ultra-marathon was due to an increased fluid intake.
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Affiliation(s)
- Caroline Cejka
- Institute of General Practice and for Health Services Research, University of Zurich, Zurich, Switzerland.
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