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Haddad T, Spence AL, Peiffer J, Blain GM, Brisswalter J, Abbiss CR. The Improvement in Exercise Performance during Reduced Muscle Mass Exercise is Associated with an Increase in Femoral Blood Flow in Older and Younger Endurance-Trained Athletes. J Sports Sci Med 2024; 23:46-55. [PMID: 38455445 PMCID: PMC10915611 DOI: 10.52082/jssm.2024.46] [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: 10/09/2023] [Accepted: 12/01/2023] [Indexed: 03/09/2024]
Abstract
This study investigated whether the improved performance observed with maximal self-paced single-leg (SL), compared with double-leg (DL) cycling, is associated with enhanced femoral blood flow and/or altered tissue oxygenation. The hyperaemic response to exercise was assessed in younger and older athletes. Power output was measured in 12 older (65 ± 4 y) and 12 younger (35 ± 5 y) endurance-trained individuals performing 2 x 3 min maximal self-paced exercise using SL and DL cycling. Blood flow (BF) in the femoral artery was assessed using Doppler ultrasound and muscle oxygenation was measured using near-infrared spectroscopy on the vastus lateralis. SL cycling elicited a greater power output (295 ± 83 vs 265 ± 70 W, P < 0.001) and peak femoral BF (1749.1 ± 533.3 vs 1329.7 ± 391.7 ml/min, P < 0.001) compared with DL cycling. Older individuals had a lower peak BF in response to exercise (1355.4 ± 385.8 vs 1765.2 ± 559.6 ml/min, P = 0.019) compared with younger individuals. Peak BF in response to exercise was correlated with power output during SL (r = 0.655, P = 0.002) and DL (r = 0.666, P = 0.001) cycling. The greater exercise performance during SL compared with DL cycling may be partly explained by a greater hyperaemic response when reducing active muscle mass. Despite regular endurance training, older athletes had a lower femoral BF in response to maximal self-paced exercise compared with younger athletes.
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Affiliation(s)
- Toni Haddad
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia
- Université Côte d'Azur, LAMHESS, France
| | - Angela L Spence
- Curtin School of Allied Health, Exercise and Sport Science Discipline, Curtin University, WA, Australia
- Curtin Health Innovation Research Institute, Curtin University, WA, Australia
| | - Jeremiah Peiffer
- Centre for Healthy Ageing, Murdoch University, Murdoch, WA, Australia
| | | | | | - Chris R Abbiss
- Centre for Human Performance, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia
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2
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Kwakye J, Ariyo OW, Ghareeb AFA, Hartono E, Sovi S, Aryal B, Milfort MC, Fuller AL, Rekaya R, Aggrey SE. Effect of Glucose Supplementation on Apoptosis in the Pectoralis major of Chickens Raised under Thermoneutral or Heat Stress Environment. Genes (Basel) 2023; 14:1922. [PMID: 37895271 PMCID: PMC10606071 DOI: 10.3390/genes14101922] [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: 09/10/2023] [Revised: 09/26/2023] [Accepted: 10/05/2023] [Indexed: 10/29/2023] Open
Abstract
Reduced feed intake during heat stress (HS) disrupts glucose homeostasis, thereby resulting in endoplasmic reticulum (ER) stress and triggering apoptosis in chickens. We hypothesize that glucose supplementation could reduce apoptosis in chickens raised under HS. This study comprised 456 28-day-old broiler chickens randomly assigned to four treatment combinations under glucose supplementation and HS. The treatments were TN0, TN6, HS0, and HS6 with two glucose levels (0% and 6%) and two temperature levels (25 °C (thermoneutral-TN) and 35 °C (8.00 AM to 8.00 PM, (HS)). After 7 days post-HS, the blood glucose level for the HS6 group was higher than for TN0, TN6, and HS0. We studied the mRNA expression of genes and caspase-3 activity in the four experimental groups. The expressions of GCN2, ATF4, CHOP, and FOXO3a increased during HS regardless of glucose supplementation, while PERK and MAFbx increased only under HS with glucose supplementation. We show that under TN conditions, glucose supplementation led to a significant increase in cellular apoptosis in the Pectoralis (P.) major. However, under HS with glucose, the level of apoptosis was similar to that of chickens raised under TN conditions with no glucose supplementation. The utility of glucose to curtail apoptosis under HS should be tested under other intense models of HS.
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Affiliation(s)
- Josephine Kwakye
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; (J.K.); (O.W.A.); (A.F.A.G.); (E.H.); (S.S.); (B.A.); (M.C.M.); (A.L.F.)
| | - Oluwatomide W. Ariyo
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; (J.K.); (O.W.A.); (A.F.A.G.); (E.H.); (S.S.); (B.A.); (M.C.M.); (A.L.F.)
| | - Ahmed F. A. Ghareeb
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; (J.K.); (O.W.A.); (A.F.A.G.); (E.H.); (S.S.); (B.A.); (M.C.M.); (A.L.F.)
| | - Evan Hartono
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; (J.K.); (O.W.A.); (A.F.A.G.); (E.H.); (S.S.); (B.A.); (M.C.M.); (A.L.F.)
| | - Selorm Sovi
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; (J.K.); (O.W.A.); (A.F.A.G.); (E.H.); (S.S.); (B.A.); (M.C.M.); (A.L.F.)
| | - Bikash Aryal
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; (J.K.); (O.W.A.); (A.F.A.G.); (E.H.); (S.S.); (B.A.); (M.C.M.); (A.L.F.)
| | - Marie C. Milfort
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; (J.K.); (O.W.A.); (A.F.A.G.); (E.H.); (S.S.); (B.A.); (M.C.M.); (A.L.F.)
| | - Alberta L. Fuller
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; (J.K.); (O.W.A.); (A.F.A.G.); (E.H.); (S.S.); (B.A.); (M.C.M.); (A.L.F.)
| | - Romdhane Rekaya
- Department of Animal and Dairy Science, University of Georgia, Athens, GA 30602, USA;
| | - Samuel E. Aggrey
- NutriGenomics Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; (J.K.); (O.W.A.); (A.F.A.G.); (E.H.); (S.S.); (B.A.); (M.C.M.); (A.L.F.)
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Hamada N, Wadazumi T, Hirata Y, Watanabe H, Hongu N, Arai N. Effects of Trehalose Solutions at Different Concentrations on High-Intensity Intermittent Exercise Performance. Nutrients 2022; 14:nu14091776. [PMID: 35565744 PMCID: PMC9101545 DOI: 10.3390/nu14091776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/08/2022] [Accepted: 04/20/2022] [Indexed: 11/25/2022] Open
Abstract
Trehalose solution ingested during exercise induces gradual increases in blood glucose levels and the insulin response compared with glucose solution. Trehalose solution aids in the maintenance of performance in the later stages of prolonged exercise. The purpose of this study was to identify the lowest concentration at which the properties of trehalose could be exploited. Groups of 12 healthy men (21.3 ± 1.3 years) and 10 healthy men (21.1 ± 0.7 years) with recreational training were included in experiments 1 and 2, respectively. Both experiments followed the same protocol. After fasting for 12 h, the participants performed a 60 min constant-load exercise at 40% V˙O2 peak using a bicycle ergometer and ingested 500 mL of a trial drink (experiment 1: water, 8% glucose, and 6 or 8% trehalose; experiment 2: 4 or 6% trehalose). They performed four sets of the Wingate test combined with a 30 min constant-load exercise at 40% V˙O2 peak. The experiment was conducted using a randomized cross-over design; trial drink experiments were conducted over intervals of 7 to 12 days. The exercise performance was evaluated based on mean power in the Wingate test. Blood was collected from the fingertip at 12 points during each experiment to measure blood glucose levels. During the high-intensity 5 h intermittent exercise, no differences were found between the groups in exercise performance in the later stages with concentrations of 8, 6, and 4% trehalose solution. The results suggest that trehalose could be useful for making a new type of mixed carbohydrate solution. Further studies to determine the trehalose response of individual athletes during endurance exercise are needed.
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Affiliation(s)
- Naomi Hamada
- Graduate School of Health and Well-Being, Department of Health and Well-Being, Kansai University, 1-11-1, Kaorigaoka-cho, Sakai-ku, Sakai 590-8515, Osaka, Japan; (T.W.); (Y.H.)
- Department of Applied Food Science, Higashiosaka Junior College, 3-1-1, Nishizutsumigakuen-cho, Higashiosaka 577-8567, Osaka, Japan
- Correspondence: ; Tel.: +81-6-6782-2824
| | - Tsuyoshi Wadazumi
- Graduate School of Health and Well-Being, Department of Health and Well-Being, Kansai University, 1-11-1, Kaorigaoka-cho, Sakai-ku, Sakai 590-8515, Osaka, Japan; (T.W.); (Y.H.)
| | - Yoko Hirata
- Graduate School of Health and Well-Being, Department of Health and Well-Being, Kansai University, 1-11-1, Kaorigaoka-cho, Sakai-ku, Sakai 590-8515, Osaka, Japan; (T.W.); (Y.H.)
- Department of Food and Nutritional Science, Kobe Women’s Junior College, 4-7-2, Nakamachi, Minatojima, Chuo-ku, Kobe 650-0046, Hyogo, Japan
| | - Hitoshi Watanabe
- Research Center for Urban Health and Sports, Osaka Metropolitan University, 3-3-138, Sugimoto, Sumiyoshi-ku 558-8585, Osaka, Japan;
| | - Nobuko Hongu
- Graduate School of Human Life Science, Department of Food and Human Life Science, Osaka Metropolitan University, 3-3-138, Sugimoto, Sumiyoshi-ku 558-8585, Osaka, Japan;
| | - Norie Arai
- Hayashibara, Co., Ltd., 675-1, Fujisaki, Naka-ku 702-8006, Okayama, Japan;
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Gómez-García R, Vilas-Boas AA, Machado M, Campos DA, Aguilar CN, Madureira AR, Pintado M. Impact of simulated in vitro gastrointestinal digestion on bioactive compounds, bioactivity and cytotoxicity of melon (Cucumis melo L. inodorus) peel juice powder. FOOD BIOSCI 2022. [DOI: 10.1016/j.fbio.2022.101726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Energy Requirements and Nutritional Strategies for Male Soccer Players: A Review and Suggestions for Practice. Nutrients 2022; 14:nu14030657. [PMID: 35277016 PMCID: PMC8838370 DOI: 10.3390/nu14030657] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/31/2022] [Accepted: 02/01/2022] [Indexed: 02/06/2023] Open
Abstract
Soccer is a high intensity intermittent sport, featuring critical events completed at high/maximal intensity which is superimposed onto an aerobic base of lower intensity activities and rest. Due to these varying energic demands and the duration of competition the need for optimal nutritional strategies to offset and delay fatigue are paramount. Over the last 50 years, several investigations have been reported on aspects of soccer be they nutrition-focused or those concerning the demands of the sport. Emanating from these scientific papers, observations have been made on the likely factors which result in the fatigue during match-play. Factors such as muscle glycogen depletion and hypoglycaemia are discussed. Studies on the energy demands of soccer have employed a variety of methodologies which are briefly reviewed and vary between the use of heart rate telemetry to the use of global positioning systems (GPS). Moving on from observations of the energy demands of the sport leads to the major focus of this review which highlights key nutritional strategies to support the preparation and recovery of male soccer players to enhance performance, or at least to enable players to perform adequately. This review examines relevant methodologies in assessing training and competitive energy costs as well as the concomitant energy intakes demanded for successful performance outcomes. In order to bring an applied aspect to the overall findings from areas discussed, some practical ideas of feeding strategies are presented.
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Rauch CE, McCubbin AJ, Gaskell SK, Costa RJS. Feeding Tolerance, Glucose Availability, and Whole-Body Total Carbohydrate and Fat Oxidation in Male Endurance and Ultra-Endurance Runners in Response to Prolonged Exercise, Consuming a Habitual Mixed Macronutrient Diet and Carbohydrate Feeding During Exercise. Front Physiol 2022; 12:773054. [PMID: 35058795 PMCID: PMC8764139 DOI: 10.3389/fphys.2021.773054] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/16/2021] [Indexed: 12/31/2022] Open
Abstract
Using metadata from previously published research, this investigation sought to explore: (1) whole-body total carbohydrate and fat oxidation rates of endurance (e.g., half and full marathon) and ultra-endurance runners during an incremental exercise test to volitional exhaustion and steady-state exercise while consuming a mixed macronutrient diet and consuming carbohydrate during steady-state running and (2) feeding tolerance and glucose availability while consuming different carbohydrate regimes during steady-state running. Competitively trained male endurance and ultra-endurance runners (n = 28) consuming a balanced macronutrient diet (57 ± 6% carbohydrate, 21 ± 16% protein, and 22 ± 9% fat) performed an incremental exercise test to exhaustion and one of three 3 h steady-state running protocols involving a carbohydrate feeding regime (76-90 g/h). Indirect calorimetry was used to determine maximum fat oxidation (MFO) in the incremental exercise and carbohydrate and fat oxidation rates during steady-state running. Gastrointestinal symptoms (GIS), breath hydrogen (H2), and blood glucose responses were measured throughout the steady-state running protocols. Despite high variability between participants, high rates of MFO [mean (range): 0.66 (0.22-1.89) g/min], Fatmax [63 (40-94) % V̇O2max], and Fatmin [94 (77-100) % V̇O2max] were observed in the majority of participants in response to the incremental exercise test to volitional exhaustion. Whole-body total fat oxidation rate was 0.8 ± 0.3 g/min at the end of steady-state exercise, with 43% of participants presenting rates of ≥1.0 g/min, despite the state of hyperglycemia above resting homeostatic range [mean (95%CI): 6.9 (6.7-7.2) mmol/L]. In response to the carbohydrate feeding interventions of 90 g/h 2:1 glucose-fructose formulation, 38% of participants showed breath H2 responses indicative of carbohydrate malabsorption. Greater gastrointestinal symptom severity and feeding intolerance was observed with higher carbohydrate intakes (90 vs. 76 g/h) during steady-state exercise and was greatest when high exercise intensity was performed (i.e., performance test). Endurance and ultra-endurance runners can attain relatively high rates of whole-body fat oxidation during exercise in a post-prandial state and with carbohydrate provisions during exercise, despite consuming a mixed macronutrient diet. Higher carbohydrate intake during exercise may lead to greater gastrointestinal symptom severity and feeding intolerance.
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Affiliation(s)
- Christopher E Rauch
- Department of Nutrition, Dietetics and Food, Monash University, Melbourne, VIC, Australia
| | - Alan J McCubbin
- Department of Nutrition, Dietetics and Food, Monash University, Melbourne, VIC, Australia
| | - Stephanie K Gaskell
- Department of Nutrition, Dietetics and Food, Monash University, Melbourne, VIC, Australia
| | - Ricardo J S Costa
- Department of Nutrition, Dietetics and Food, Monash University, Melbourne, VIC, Australia
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Bourdas DI, Souglis A, Zacharakis ED, Geladas ND, Travlos AK. Meta-Analysis of Carbohydrate Solution Intake during Prolonged Exercise in Adults: From the Last 45+ Years' Perspective. Nutrients 2021; 13:4223. [PMID: 34959776 PMCID: PMC8704222 DOI: 10.3390/nu13124223] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/02/2021] [Accepted: 11/22/2021] [Indexed: 12/17/2022] Open
Abstract
Carbohydrate (CHO) supplementation during prolonged exercise postpones fatigue. However, the optimum administration timing, dosage, type of CHO intake, and possible interaction of the ergogenic effect with athletes' cardiorespiratory fitness (CRF) are not clear. Ninety-six studies (from relevant databases based on predefined eligibility criteria) were selected for meta-analysis to investigate the acute effect of ≤20% CHO solutions on prolonged exercise performance. The between-subject standardized mean difference [SMD = ([mean post-value treatment group-mean post-value control group]/pooled variance)] was assessed. Overall, SMD [95% CI] of 0.43 [0.35, 0.51] was significant (p < 0.001). Subgroup analysis showed that SMD was reduced as the subjects' CRF level increased, with a 6-8% CHO solution composed of GL:FRU improving performance (exercise: 1-4 h); administration during the event led to a superior performance compared to administration before the exercise, with a 6-8% single-source CHO solution increasing performance in intermittent and 'stop and start' sports and an ~6% CHO solution appearing beneficial for 45-60 min exercises, but there were no significant differences between subjects' gender and age groups, varied CHO concentrations, doses, or types in the effect measurement. The evidence found was sound enough to support the hypothesis that CHO solutions, when ingested during endurance exercise, have ergogenic action and a possible crossover interaction with the subject's CRF.
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Affiliation(s)
- Dimitrios I. Bourdas
- Section of Sport Medicine & Biology of Exercise, School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 41 Ethnikis Antistasis, 17237 Athens, Greece;
| | - Athanasios Souglis
- Section of Didactics and Coaching in Sport Games, School of Physical Education & Sport Science, National and Kapodistrian University of Athens, 41 Ethnikis Antistasis, 17237 Athens, Greece; (A.S.); (E.D.Z.)
| | - Emmanouil D. Zacharakis
- Section of Didactics and Coaching in Sport Games, School of Physical Education & Sport Science, National and Kapodistrian University of Athens, 41 Ethnikis Antistasis, 17237 Athens, Greece; (A.S.); (E.D.Z.)
| | - Nickos D. Geladas
- Section of Sport Medicine & Biology of Exercise, School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 41 Ethnikis Antistasis, 17237 Athens, Greece;
| | - Antonios K. Travlos
- Department of Sports Organization and Management, Faculty of Human Movement and Quality of Life Sciences, University of Peloponnese, Efstathiou and Stamatikis Valioti & Plataion Avenue, 23100 Tripoli, Greece;
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Burke LM. Nutritional approaches to counter performance constraints in high-level sports competition. Exp Physiol 2021; 106:2304-2323. [PMID: 34762329 PMCID: PMC9299184 DOI: 10.1113/ep088188] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 11/03/2021] [Indexed: 12/12/2022]
Abstract
New Findings What is the topic of this review? The nutritional strategies that athletes use during competition events to optimize performance and the reasons they use them. What advances does it highlight? A range of nutritional strategies can be used by competitive athletes, alone or in combination, to address various event‐specific factors that constrain event performance. Evidence for such practices is constantly evolving but must be combined with understanding of the complexities of real‐life sport for optimal implementation.
Abstract High‐performance athletes share a common goal despite the unique nature of their sport: to pace or manage their performance to achieve the highest sustainable outputs over the duration of the event. Periodic or sustained decline in the optimal performance of event tasks, involves an interplay between central and peripheral phenomena that can often be reduced or delayed in onset by nutritional strategies. Contemporary nutrition practices undertaken before, during or between events include strategies to ensure the availability of limited muscle fuel stores. This includes creatine supplementation to increase muscle phosphocreatine content and consideration of the type, amount and timing of dietary carbohydrate intake to optimize muscle and liver glycogen stores or to provide additional exogenous substrate. Although there is interest in ketogenic low‐carbohydrate high‐fat diets and exogenous ketone supplements to provide alternative fuels to spare muscle carbohydrate use, present evidence suggests a limited utility of these strategies. Mouth sensing of a range of food tastants (e.g., carbohydrate, quinine, menthol, caffeine, fluid, acetic acid) may provide a central nervous system derived boost to sports performance. Finally, despite decades of research on hypohydration and exercise capacity, there is still contention around their effect on sports performance and the best guidance around hydration for sporting events. A unifying model proposes that some scenarios require personalized fluid plans while others might be managed by an ad hoc approach (ad libitum or thirst‐driven drinking) to fluid intake.
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Affiliation(s)
- Louise M Burke
- Exercise and Nutrition Research Program, Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, Australia
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Hulton AT, Malone JJ, Campbell IT, MacLaren DPM. The effect of the menstrual cycle and hyperglycaemia on hormonal and metabolic responses during exercise. Eur J Appl Physiol 2021; 121:2993-3003. [PMID: 34235576 PMCID: PMC8505395 DOI: 10.1007/s00421-021-04754-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 06/18/2021] [Indexed: 11/28/2022]
Abstract
Purpose Variations in substrate metabolism have been identified in women during continuous steady-state aerobic exercise performed at the same relative intensity throughout discrete phases of the menstrual cycle, although some evidence exists that this is abolished when carbohydrate is ingested. This investigation examined the effects of a supraphysiologic exogenous glucose infusion protocol, administered during two phases of the menstrual cycle (follicular and luteal) in eumenorrheic women to identify differences between metabolic, hormonal and substrate oxidative responses. Methods During the experimental conditions, blood glucose was infused intravenously at rates to “clamp” blood glucose at 10 mM in seven healthy females (age 20 ± 1 y, mass 55.0 ± 4.1 kg, \documentclass[12pt]{minimal}
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\begin{document}$$\dot V{O_{2peak}}$$\end{document}V˙O2peak. During the rest period and throughout exercise, blood metabolites and hormones were collected at regular intervals, in addition to expired air for the measurement of substrate oxidation. Results Significant differences between ovarian hormones and menstrual phase were identified, with estrogen significantly higher during the luteal phase compared to the follicular phase (213.28 ± 30.70 pmol/l vs 103.86 ± 13.85 pmol/l; p = 0.016), and for progesterone (14.23 ± 4.88 vs 2.11 ± 0.36 nmol/l; p = 0.042). However, no further significance was identified in any of the hormonal, metabolite or substrate utilisation patterns between phases. Conclusion These data demonstrate that the infusion of a supraphysiological glucose dose curtails any likely metabolic influence employed by the fluctuation of ovarian hormones in eumenorrheic women during moderate exercise.
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Affiliation(s)
- A T Hulton
- Department of Nutritional Sciences, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK. .,Sport and Exercise Science, University of Surrey, Leggett Building, Guildford, GU2 7WG, UK.
| | - J J Malone
- School of Health Sciences, Liverpool Hope University, Liverpool, UK
| | - I T Campbell
- Dept of Anaesthesia, Wythenshawe Hospital, Manchester, UK
| | - D P M MacLaren
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK
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