Assessing Effectiveness of anaerobic threshold and respiratory compensation point on fat and carbohydrate oxidations during exercise in sedentary males Anaerobic Threshold and Substrate Oxidation
Main Article Content
Keywords
Exercise, Anaerobic Threshold, Respiratory Compensation Point, Fat Oxidation, Carbohydrate Oxidation, Respiratory Quotient, Metabolism
Abstract
Study Objectives: Anaerobic threshold (AT) and respiratory compensation point (RCP) are two important metabolic set points. We aimed to determine effects of exercise intensity at AT and RCP on the balance of substrate oxidation rates. Methods: Eleven male participants performed an incremental exercise test to exhaustion on a cycle ergometer to estimate AT and RCP. Subsequently, we conducted three 30 minute constant load exercise tests at AT (WAT), RCP (WRCP) and 25% below AT (W<AT) in a randomised order. Pulmonary gas exchange parameters measured breath-by-breath. We estimated substrate oxidation rate by using Frayn equations. Results: We found that AT and RCP occurred at a mean intensity of 60% (range between 53-64% of VO2peak) and 72% of VO2peak (range between 66-76% of VO2peak) respectively. Fat oxidation was found to be 0.221±0.01 g/min at W<AT and this significantly increased to 0.340±0.01 g/min at WAT and 0.326±0.03 g/min at WRCP (p<0.05). Conclusion: We found that carbohydrate oxidation was 1.621±0.03 g/min (W<AT), 1.961±0.02 g/min (WAT) and 2.417±0.1 g/min (WRCP) (p<0.05). AT and RCP provides optimal metabolic strain to all participant and stimulate more fat oxidations. Thus clinicians should consider using exercise intensity at AT and RCP to achieve the rate of highest fat oxidation.
References
2. Jeukendrup AE. Modulation of carbohydrate and fat utilization by diet, exercise and environment. Biochem Soc Trans 2003; 31(6): 1270-73.
3. Perez-Martin A, Dumortier M, Raynaud E, Brun JF, Fedou C, Bringer J, Mercier J. Balance of substrate oxidation during submaximal exercise in lean and obese people. Diabetes Metab 2001; 27(4): 466-74.
4. Kiens B, Alsted TJ, Jeppesen J. Factors regulating fat oxidation in human skeletal muscle. Obes Rev 2011; 12(10): 852-58.
5. Brooks GA, Mercier J. Balance of carbohydrate and lipid utilization during exercise: the “crossover” concept. J Appl Physiol 1994; 76(6): 2253-61.
6. Achten J, Jeukendrup AE. Relation between plasma lactate concentration and fat oxidation rates over a wide range of exercise intensities. Int J Sports Med 2004; 25(1): 32-7.
7. Nosaka N, Suzuki Y, Suemitsu H, Kasai M, Kato K, Taguchi MJ. Medium-chain triglycerides with maltodextrin increase fat oxidation during moderate-intensity exercise and extend the duration of subsequent high-intensity exercise. J Oleo Sci 2018; 67(11): 1455-62.
8. Venables MC, Achten J, Jeukendrup AE. Determinants of fat oxidation during exercise in healthy men and women: a cross-sectional study. J Appl Physiol 2005; 98(1): 160-7.
9. Dandanell S, Prest CB, Sondergard SD, Skovborg C, Dela F, Larsen S, Helge JW. Determination of the exercise intensity that elicits maximal fat oxidation in individuals with obesity. Appl Physiol Nutr Metab 2017; 42(4): 405-12.
10. Boon H, Jonkers RA, Koopman R, Blaak E, Saris W, Wagenmakers A, Van Loon LJ. Substrate source use in older, trained males after decades of endurance training. Med Sci Sports Exerc 2007; 39(12): 2160-70.
11. Scharhag-Rosenberger F, Meyer T, Gässler N, Faude O, Kindermann W. Exercise at given percentages of VO2max: heterogeneous metabolic responses between individuals. J Sci Med Sport 2010; 13(1): 74-9.
12. Whipp BJ, Wagner PD, Agusti A. Determinants of the physiological systems responses to muscular exercise in healthy subjects. In: Clinical Exercise Testing (Ed: P. Palange and S.A. Ward), Eur Res Mono 2007; 40: 1-35.
13. Salvadego D, Lazzer S, Busti C. Gas exchange kinetics in obese adolescents. Inferences on exercise tolerance and prescription. Am J Physiol Regul Integr Comp Physiol 2010; 299(5): 1298-1305.
14. Whipp BJ, Davis JA, Torres F. A test to determine parameters of aerobic function during exercise. J Appl Physiol Respir Environ Exerc Physiol 1981; 50(1): 217-21.
15. Ozcelik O, Wards SA, Whipp BJ. Effects of altered body CO2 stores on pulmonary gas exchange dynamics during incremental exercise in humans. Exp Physiol 1999; 84(5): 999-1011.
16. Hulston CJ, Venables MC, Mann CH, Martin C, Philp A, Baar K, Jeukendrup AE. Training with low muscle glycogen enhances fat metabolism in well-trained cyclist. Med Sci Sports Exerc 2010; 42(11): 2046-55.
17. Beaver WL, Wasserman K, Whipp BJ. A new method for detecting anaerobic threshold by gas exchange. J Appl Physiol 1986; 60(6): 2020-27.
18. Whipp BJ, Ward SA, Wasserman K. Respiratory markers of the anaerobic threshold. Adv Cardiol 1986; 35, 47-64.
19. Ozcelik O, Kelestimur H. Effects of acute hypoxia on the estimation of lactate threshold from ventilatory gas exchange indices during an incremental exercise test. Physiol Res 2004; 53(6): 653-59.
20. Whipp BJ, Davis JA, Wasserman K. Ventilatory control of the 'isocapnic buffering' region in rapidly-incremental exercise. Respir Physiol 1989; 76(3): 357-67.
21. Algul S, Ozcelik O, Yilmaz B. Evaluation of relationship between aerobic fitness level and range of isocapnic buffering periods during incremental exercise test. Cell Mol Biol (Noisy-le-grand) 2017; 63(3): 78-2.
22. Beaver WL, Lamarra N, Wasserman K. Breath-by-breath measurement of true alveolar gas exchange. J Appl Physiol Respir Environ Exerc Physiol 1981; 51(6): 1662-75.
23. Frayn KN. Calculation of substrate oxidation rates in vivo from gaseous exchange. J Appl Physiol 1983; 55(2): 628-34.
24. Christmass MA, Dawson B, Passeretto P, Arthur PG. A comparison of skeletal muscle oxygenation and fuel use in sustained continuous and intermittent exercise. Eur J Appl Physiol Occup Physiol 1999; 80(5): 423-35.
25. Algul S, Ugur FA, Ayar A, Ozcelik O. Comparative determination of ventilatory efficiency from constant load and incremental exercise testing. Cell Mol Biol (Noisy-le-grand) 2017; 63(7): 26-30.
26. Knechtle B, Muller G, Willmann F, Kotteck K, Eser P, Knecht H. Fat oxidation in men and women endurance athletes in running and cycling. Int J Sports Med 2004; 25(1): 38-4.
27. McArdle W, Katch FKV. Essentials of exercise physiology. Lippincott Williams & Wilkins 2000.
28. Ozcelik O, Ozkan Y, Algul S, Colak R. Beneficial effects of training at the anaerobic threshold in addition to pharmacotherapy on weight loss, body composition, and exercise performance in women with obesity. Patient Prefer Adherence 2015; 13(9): 999-1004.
29. Groop LC, Bonadonna RC, Simonson DC, Petrides AS, Shank M, DeFronzo RA. Effect of insulin on oxidative and nonoxidative pathways of free fatty acid metabolism in human obesity. Am J Physiol 1992; 263(1): 79-4.
30. Kim HK, Ando K, Tabata H, Konishi M, Takahashi M, Nishimaki M. Effects of different intensities of endurance exercise in morning and evening on the lipid metabolism response. J Sports Sci Med 2016; 15(3): 467-76.
31. Rynders CA, Angadi SS, Weltman NY, Gaesser GA, Weltman A. Oxygen uptake and ratings of perceived exertion at the lactate threshold and maximal fat oxidation rate in untrained adults. Eur J Appl Physiol 2011; 111(9): 2063-68.
32. Gmada N, Marzouki H, Haboubi M, Tabka Z, Shephard RJ, Bouhlel E. Crossover and maximal fat-oxidation points in sedentary healthy subjects: methodological issues. Diabetes Metab 2012; 38(1), 40-5.
33. Bircher S, Knechtle B, Knecht H. Is the intensity of the highest fat oxidation at the lactate concentration of 2 mmol L(-1)? A comparison of two different exercise protocols. Eur J Clin Invest 2005; 35(8): 491-98.
34. Kuo CC, Fattor JA, Henderson GC, Brooks GA. Lipid oxidation in fit young adults during post exercise recovery. J Appl Physiol 2005; 99(1): 349-56.
35. Astorino TA. Is the ventilatory threshold coincident with maximal fat oxidation during submaximal exercise in women?. J Sports Med Phys Fitness 2000; 40(3): 209-16.
36. Whipp BJ. Domains of aerobic function and their limiting parameters. In: The Physiology and Pathophysiology of Exercise Tolerance. S.A. Ward (ed), Plenum Press, New York, NY 1996; 83-9.