Effects of pacing strategy on metabolic responses to 2-min intense exercise in Thoroughbred horses.
Abstract: Evidence suggests that positive pacing strategy improves exercise performance and fatigue tolerance in athletic events lasting 1-5 min. This study investigated muscle metabolic responses to positive and negative pacing strategies in Thoroughbred horses. Eight Thoroughbred horses performed 2 min treadmill running using positive (1 min at 110% maximal O uptake [V̇Omax], followed by 1 min at 90% V̇Omax) and negative (1 min at 90% V̇Omax, followed by 1 min at 110% V̇Omax) pacing strategies. The arterial-mixed venous O difference did not significantly differ between the two strategies. Plasma lactate levels increased toward 2 min, with significantly higher concentrations during positive pacing than during negative pacing. Muscle glycogen level was significantly lower at 1 and 2 min of positive pacing than those of negative pacing. Metabolomic analysis showed that the sum of glycolytic intermediates increased during the first half of positive pacing and the second half of negative pacing. Regardless of pacing strategy, the sum of tricarboxylic acid cycle metabolites increased during the first half but remained unchanged thereafter. Our data suggest that positive pacing strategy is likely to activate glycolytic metabolism to a greater extent compared to negative pacing, even though the total workload is identical.
© 2024. The Author(s).
Publication Date: 2024-08-07 PubMed ID: 39112781PubMed Central: 2769631DOI: 10.1038/s41598-024-69339-xGoogle Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research article explores how different pacing strategies affect metabolic responses in Thoroughbred horses during intense, short-duration exercise. The findings suggest that a positive pacing strategy activates glycolytic metabolism more effectively than a negative pacing strategy, even though the overall workload is the same.
Research Methodology
- The research involved eight Thoroughbred horses. These horses were subjected to 2-minute intense treadmill running sessions.
- Two distinct pacing strategies were employed for this experiment: A positive pacing strategy (one-minute run at 110% maximum oxygen uptake, followed by a one-minute run at 90% maximum oxygen uptake), and a negative pacing strategy (one-minute run at 90% maximum oxygen uptake, followed by a one-minute run at 110% maximum oxygen uptake).
- The researchers then analyzed the metabolic responses to these different pacing strategies by conducting metabolomic analysis, measuring plasma lactate levels, and the arterial-mixed venous oxygen difference, among other factors.
Key Findings
- The arterial-mixed venous oxygen difference, an indicator of the volume of oxygen absorbed by the muscles, didn’t show a significant difference between the two pacing strategies.
- Plasma lactate levels showed an increase towards the end of the 2-minute exercise, with higher concentrations observed during the positive pacing strategy compared to the negative one. This suggests that positive pacing leads to a higher rate of anaerobic metabolism.
- Muscle glycogen levels, which indicate the horse’s energy storage, were significantly lower at 1 and 2 minutes during positive pacing compared to negative pacing. This suggests that positive pacing leads to quicker energy depletion.
- The sum of glycolytic intermediates, which indicates the level of glycolysis – the metabolic pathway that transforms glucose into pyruvate, increased during the first half of positive pacing and the second half of negative pacing, suggesting a higher rate of glucose metabolism during the positive pacing.
- Regardless of the strategy, the sum of tricarboxylic acid cycle metabolites, indicating the level of aerobic metabolism, increased during the first half but remained unchanged thereafter.
Conclusions
- The research suggests that positive pacing leads to a greater activation of glycolytic metabolism compared to negative pacing, even when the total workload is identical.
- This metabolic difference could potentially explain why positive pacing might improve exercise performance and fatigue tolerance in events lasting between one to five minutes, as suggested by previous evidence.
Cite This Article
APA
Takahashi K, Mukai K, Ebisuda Y, Sugiyama F, Yoshida T, Hatta H, Kitaoka Y.
(2024).
Effects of pacing strategy on metabolic responses to 2-min intense exercise in Thoroughbred horses.
Sci Rep, 14(1), 18352.
https://doi.org/10.1038/s41598-024-69339-x Publication
Researcher Affiliations
- Department of Sports Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1, Komaba, Meguro-Ku, Tokyo, 153-8902, Japan. kenyatakahashi@idaten.c.u-tokyo.ac.jp.
- Sports Science Division, Equine Research Institute, Japan Racing Association, Tochigi, Japan.
- Sports Science Division, Equine Research Institute, Japan Racing Association, Tochigi, Japan.
- Sports Science Division, Equine Research Institute, Japan Racing Association, Tochigi, Japan.
- Sports Science Division, Equine Research Institute, Japan Racing Association, Tochigi, Japan.
- Department of Sports Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1, Komaba, Meguro-Ku, Tokyo, 153-8902, Japan.
- Department of Human Sciences, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-Ku, Yokohama, Kanagawa, 221-8686, Japan. kitaoka@kanagawa-u.ac.jp.
MeSH Terms
- Animals
- Horses
- Physical Conditioning, Animal / physiology
- Lactic Acid / blood
- Lactic Acid / metabolism
- Glycogen / metabolism
- Oxygen Consumption
- Muscle, Skeletal / metabolism
- Male
- Exercise Test
- Glycolysis
- Female
- Citric Acid Cycle
Grant Funding
- 21K21249 / Japan Society for the Promotion of Science
- 20H04071 / Japan Society for the Promotion of Science
References
This article includes 41 references
- Abbiss CR, Laursen PB. Describing and understanding pacing strategies during athletic competition.. Sports Med. (Auckland, New Zealand) 38, 239–252 (2008).
- Bishop D, Bonetti D, Dawson B. The influence of pacing strategy on VO2 and supramaximal kayak performance.. Med. Sci. Sports Exerc. 34, 1041–1047 (2002).
- Jones AM, Wilkerson DP, Vanhatalo A, Burnley M. Influence of pacing strategy on O2 uptake and exercise tolerance.. Scand. J. Med. Sci. Sports 18, 615–626 (2008).
- Foster C. Pattern of energy expenditure during simulated competition.. Med. Sci. Sports Exerc. 35, 826–831 (2003).
- Bailey SJ, Vanhatalo A, DiMenna FJ, Wilkerson DP, Jones AM. Fast-start strategy improves VO2 kinetics and high-intensity exercise performance.. Med. Sci. Sports Exerc. 43, 457–467 (2011).
- de Koning JJ, Bobbert MF, Foster C. Determination of optimal pacing strategy in track cycling with an energy flow model.. J. Sci. Med. Sport 2, 266–277 (1999).
- Hettinga FJ, De Koning JJ, Broersen FT, Van Geffen P, Foster C. Pacing strategy and the occurrence of fatigue in 4000 m cycling time trials.. Med. Sci. Sports Exerc. 38, 1484–1491 (2006).
- Hettinga FJ, De Koning JJ, Meijer E, Teunissen L, Foster C. Biodynamics. Effect of pacing strategy on energy expenditure during a 1500 m cycling time trial.. Med. Sci. Sports Exerc. 39, 2212–2218 (2007).
- Foster C. Effect of pacing strategy on cycle time trial performance.. Med. Sci. Sports Exerc. 25, 383–388 (1993).
- Goodwin ML, Harris JE, Hernandez A, Gladden LB. Blood lactate measurements and analysis during exercise: A guide for clinicians.. J. Diabetes Sci. Technol. 1, 558–569 (2007).
- Kitaoka Y. Muscle glycogen breakdown and lactate metabolism during intensive exercise in Thoroughbred horses.. J. Phys. Fit. Sports Med. 3, 451–456 (2014).
- Jones JH. Oxygen transport during exercise in large mammals. I. Adaptive variation in oxygen demand.. J. Appl. Physiol. (Bethesda, Md.: 1985) 67, 862–870 (1989).
- Lindholm A, Bjerneld H, Saltin B. Glycogen depletion pattern in muscle fibres of trotting horses.. Acta Physiol. Scand. 90, 475–484 (1974).
- Lindholm A, Piehl K. Fibre composition, enzyme activity and concentrations of metabolites and electrolytes in muscles of standardbred horses.. Acta Vet. Scand. 15, 287–309 (1974).
- Eaton MD, Evans DL, Hodgson DR, Rose RJ. Maximal accumulated oxygen deficit in thoroughbred horses.. J. Appl. Physiol. (Bethesda, Md.: 1985) 78, 1564–1568 (1995).
- Mukai K. Effects of maintaining different exercise intensities during detraining on aerobic capacity in Thoroughbreds.. Am. J. Vet. Res. 78, 215–222 (2017).
- Kitaoka Y. Effect of training and detraining on monocarboxylate transporter (MCT) 1 and MCT4 in Thoroughbred horses.. Exp. Physiol. 96, 348–355 (2011).
- Mukai K. Physiological and skeletal muscle responses to high-intensity interval exercise in Thoroughbred horses.. Front. Vet. Sci. 10, 1241266 (2023).
- Lacombe VA, Hinchcliff KW, Kohn CW, Devor ST, Taylor LE. Effects of feeding meals with various soluble-carbohydrate content on muscle glycogen synthesis after exercise in horses.. Am. J. Vet. Res. 65, 916–923 (2004).
- Takahashi K, Kitaoka Y, Matsunaga Y, Hatta H. Effect of post-exercise lactate administration on glycogen repletion and signaling activation in different types of mouse skeletal muscle.. Curr. Res. Physiol. 3, 34–43 (2020).
- Kanehisa M, Goto S. KEGG: Kyoto encyclopedia of genes and genomes.. Nucleic Acids Res. 28, 27–30 (2000).
- Spriet LL, Howlett RA, Heigenhauser GJ. An enzymatic approach to lactate production in human skeletal muscle during exercise.. Med. Sci. Sports Exerc. 32, 756–763 (2000).
- Jurica MS. The allosteric regulation of pyruvate kinase by fructose-1,6-bisphosphate.. Structure 6, 195–210 (1998).
- Parolin ML. Regulation of skeletal muscle glycogen phosphorylase and PDH during maximal intermittent exercise.. Am. J. Physiol. 277, E890-900 (1999).
- Gastin PB, Costill DL, Lawson DL, Krzeminski K, McConell GK. Accumulated oxygen deficit during supramaximal all-out and constant intensity exercise.. Med. Sci. Sports Exerc. 27, 255–263 (1995).
- Walton ME, Ebert D, Haller RG. Relative rates of anaplerotic flux in rested and contracted rat skeletal muscle measured by 13C NMR spectroscopy.. J. Physiol. 548, 541–548 (2003).
- Gibala MJ, MacLean DA, Graham TE, Saltin B. Anaplerotic processes in human skeletal muscle during brief dynamic exercise.. J. Physiol. 502(Pt 3), 703–713 (1997).
- Bruce M. Glutamine supplementation promotes anaplerosis but not oxidative energy delivery in human skeletal muscle.. Am. J. Physiol. Endocrinol. Metab. 280, E669-675 (2001).
- Gibala MJ, Peirce N, Constantin-Teodosiu D, Greenhaff PL. Exercise with low muscle glycogen augments TCA cycle anaplerosis but impairs oxidative energy provision in humans.. J. Physiol. 540, 1079–1086 (2002).
- Randle PJ, England PJ, Denton RM. Control of the tricarboxylate cycle and its interactions with glycolysis during acetate utilization in rat heart.. Biochem. J. 117, 677–695 (1970).
- Essén B, Kaijser L. Regulation of glycolysis in intermittent exercise in man.. J. Physiol. 281, 499–511 (1978).
- Gibala MJ, Tarnopolsky MA, Graham TE. Tricarboxylic acid cycle intermediates in human muscle at rest and during prolonged cycling.. Am. J. Physiol. 272, E239-244 (1997).
- Gibala MJ, MacLean DA, Graham TE, Saltin B. Tricarboxylic acid cycle intermediate pool size and estimated cycle flux in human muscle during exercise.. Am. J. Physiol. 275, E235-242 (1998).
- Gladden LB. Lactate metabolism: A new paradigm for the third millennium.. J. Physiol. 558, 5–30 (2004).
- Bonen A. Lactate transporters (MCT proteins) in heart and skeletal muscles.. Med. Sci. Sports Exerc. 32, 778–789 (2000).
- Gladden LB, Crawford RE, Webster MJ. Effect of lactate concentration and metabolic rate on net lactate uptake by canine skeletal muscle.. Am. J. Physiol. 266, R1095-1101 (1994).
- Mercier Q, Aftalion A. Optimal speed in Thoroughbred horse racing.. PloS ONE 15, e0235024 (2020).
- Self ZT, Spence AJ, Wilson AM. Speed and incline during thoroughbred horse racing: Racehorse speed supports a metabolic power constraint to incline running but not to decline running.. J. Appl. Physiol. (Bethesda, Md.: 1985) 113, 602–607 (2012).
- Tan H, Wilson AM. Grip and limb force limits to turning performance in competition horses.. Proc. Biol. Sci. 278, 2105–2111 (2011).
- Spence AJ, Thurman AS, Maher MJ, Wilson AM. Speed, pacing strategy and aerodynamic drafting in Thoroughbred horse racing.. Biol. Lett. 8, 678–681 (2012).
- Poole DC, Erickson HH. Highly athletic terrestrial mammals: Horses and dogs.. Compreh. Physiol. 1, 1–37 (2011).
Citations
This article has been cited 0 times.Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists