Cardiac Autonomic and Physiological Responses to Moderate- intensity Exercise in Hypoxia

Abstract

Exercise physiological responses can be markedly affected by acute hypoxia. We investigated cardiac autonomic and physiological responses to different hypoxic training protocols. Thirteen men performed three exercise sessions (5×5-min; 1-min passive recovery): normoxic exercise at 80% of the power output (PO) at the first ventilatory threshold (N), hypoxic exercise (FiO₂=14.2%) with the same PO as N (HPO) and hypoxic exercise at the same heart rate (HR) as N (HHR). PO was lower in HHR (21.1±9.3%) compared to N and HPO. Mean HR was higher in HPO (154±11 bpm, p<0.01) than N and HHR (139±10 vs. 138±9 bpm; p=0.80). SpO₂ was reduced (p<0.01) to a similar extent (p>0.05) in HPO and HHR compared to N. HR recovery (HRR) and HR variability indices were similar in N and HHR (p>0.05) but reduced in HPO (p<0.05), mirroring a delayed parasympathetic reactivation. Blood lactate and ventilation were similar in N and HHR (p>0.05) and increased in HPO (p<0.001). During recovery oxygen consumption and ventilation were similar in N and HHR (p>0.05) and increased in HPO (p<0.01). Moderate HR-matched hypoxic exercise triggers similar cardiac autonomic and physiological responses to normoxic exercise with a reduced mechanical load. On the contrary, the same absolute intensity exercise in hypoxia is associated with increased exercise-induced metabolic stress and delayed cardiac autonomic recovery.

Key words

heart rate recovery - hypoxia - post-exercise recovery, hypoxic exercise - cardiac autonomic activity

• References

• 1 Joyner MJ, Green DJ. Exercise protects the cardiovascular system: Effects beyond traditional risk factors. J Physiol 2009; 587: 5551-5558
• 2 Fiuza-Luces C, Santos-Lozano A, Joyner M, Carrera-Bastos P, Picazo O, Zugaza JL, Izquierdo M, Ruilope LM, Lucia A. Exercise benefits in cardiovascular disease: Beyond attenuation of traditional risk factors. Nat Rev Cardiol 2018; 15: 731-743
• 3 Blair SN, Kohl HW, Paffenbarger RS, Clark DG, Cooper KH, Gibbons LW. Physical fitness and all-cause mortality. JAMA 1989; 262: 2395
• 4 Hupin D, Edouard P, Gremeaux V, Garet M, Celle S, Pichot V, Maudoux D, Barthélémy J, Roche F. Physical activity to reduce mortality risk. Eur Heart J 2017; 38: 1534-1537
• 5 Millet GP, Debevec T, Brocherie F, Malatesta D, Girard O. Therapeutic use of exercising in hypoxia: Promises and limitations. Front Physiol 2016; 7: 224
• 6 Montero D, Lundby C. Effects of exercise training in hypoxia versus normoxia on vascular health. Sport Med 2016; 46: 1725-1736
• 7 Hobbins L, Hunter S, Gaoua N, Girard O. Normobaric hypoxic conditioning to maximize weight loss and ameliorate cardio-metabolic health in obese populations: A systematic review. Am J Physiol Regul Integr Comp Physiol 2017; 313: R251-R264
• 8 Pramsohler S, Burtscher M, Faulhaber M, Gatterer H, Rausch L, Eliasson A, Netzer NC. Endurance training in normobaric hypoxia imposes less physical stress for geriatric rehabilitation. Front Physiol 2017; 8: 514
• 9 De Groote E, Britto FA, Bullock L, François M, De Buck C, Nielens H, Deldicque L. Hypoxic training improves normoxic glucose tolerance in adolescents with obesity. Med Sci Sports Exerc 2018; 50: 2200-2208
• 10 Girard O, Malatesta D, Millet GP. Walking in hypoxia: An efficient treatment to lessen mechanical constraints and improve health in obese individuals?. Front Physiol 2017; 8: 73
• 11 Mourot L. Limitation of maximal heart rate in hypoxia: Mechanisms and clinical importance. Front Physiol 2018; 9: 972
• 12 Mollard P, Woorons X, Letournel M, Cornolo J, Lamberto C, Beaudry M, Richalet J-P. Role of maximal heart rate and arterial O ₂ saturation on the decrement of V̇O₂ max in moderate acute hypoxia in trained and untrained men. Int J Sports Med 2007; 28: 186-192
• 13 Calbet JAL, Robach P, Lundby C. The exercising heart at altitude. Cell Mol Life Sci. 2009; 66: 3601-3613
• 14 Fornasiero A, Savoldelli A, Skafidas S, Stella F, Bortolan L, Boccia G, Zignoli A, Schena F, Mourot L, Pellegrini B. Delayed parasympathetic reactivation and sympathetic withdrawal following maximal cardiopulmonary exercise testing (CPET) in hypoxia. Eur J Appl Physiol 2018; 118: 2189-2201
• 15 Koelwyn GJ, Wong LE, Kennedy MD, Eves ND. The effect of hypoxia and exercise on heart rate variability, immune response, and orthostatic stress. Scand J Med Sci Sports 2013; 23: e1-e8
• 16 Garber CE, Blissmer B, Deschenes MR, Franklin BA, Lamonte MJ, Lee I-M, Nieman DC, Swain DP. American College of Sports Medicine. quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults. Med Sci Sports Exerc 2011; 43: 1334-1359
• 17 Dinenno FA. Skeletal muscle vasodilation during systemic hypoxia in humans. J Appl Physiol 2016; 120: 216-225
• 18 Bourdillon N, Saugy J, Schmitt L, Rupp T, Yazdani S, Vesin J-M, Millet GP. Acute and chronic changes in baroreflex sensitivity in hypobaric vs. normobaric hypoxia. Eur J Appl Physiol. 2017; 117: 2401-2407
• 19 Favret F, Richalet J-P. Exercise and hypoxia: The role of the autonomic nervous system. Respir Physiol Neurobiol 2007; 158: 280-286
• 20 Amann M, Kayser B. Nervous system function during exercise in hypoxia. High Alt Med Biol 2009; 10: 149-164
• 21 Fisher JP. Cardiac autonomic regulation during hypoxic exercise. Am J Physiol Heart Circ Physiol 2015; 308: H1474-H1475
• 22 Al Haddad H, Mendez-Villanueva A, Bourdon PC, Buchheit M. Effect of acute hypoxia on post-exercise parasympathetic reactivation in healthy men. Front Physiol 2012; 3: 289
• 23 Mollard P, Woorons X, Letournel M, Lamberto C, Favret F, Pichon A, Beaudry M, Richalet J-P. Determinants of maximal oxygen uptake in moderate acute hypoxia in endurance athletes. Eur J Appl Physiol 2007; 100: 663-673
• 24 Grataloup O, Busso T, Castells J, Denis C, Benoit H. Evidence of decrease in peak heart rate in acute hypoxia: Effect of exercise-induced arterial hypoxemia. Int J Sports Med 2007; 28: 181-185
• 25 Sheel AW, MacNutt MJ, Querido JS. The pulmonary system during exercise in hypoxia and the cold. Exp Physiol. 2010; 95: 422-430
• 26 Mazzeo RS. Physiological responses to exercise at altitude. Sports Med. 2008; 38: 1-8
• 27 Koelwyn GJ, Wong LE, Kennedy MD, Eves ND. The effect of hypoxia and exercise on heart rate variability, immune response, and orthostatic stress. Scand J Med Sci Sports 2013; 23: e1-e8
• 28 Mann TN, Webster C, Lamberts RP, Lambert MI. Effect of exercise intensity on post-exercise oxygen consumption and heart rate recovery. Eur J Appl Physiol 2014; 114: 1809-1820
• 29 Michael S, Graham KS, Davis GM. Cardiac autonomic responses during exercise and post-exercise recovery using heart rate variability and systolic time intervals—A review. Front Physiol 2017; 8: 301
• 30 Zupet P, Princi T, Finderle Z. Effect of hypobaric hypoxia on heart rate variability during exercise: A pilot field study. Eur J Appl Physiol. 2009; 107: 345-350
• 31 Chacaroun S, Vega-Escamilla y Gonzalez I, Flore P, Doutreleau S, Verges S. Physiological responses to hypoxic constant-load and high-intensity interval exercise sessions in healthy subjects. Eur J Appl Physiol. 2019; 119: 123-134
• 32 Harriss DJ, Macsween A, Atkinson G. Standards for ethics in sport and exercise science research: 2018 update. Int J Sports Med 2017; 38: 1126-1131
• 33 Sugawara J, Murakami H, Maeda S, Kuno S, Matsuda M. Change in post-exercise vagal reactivation with exercise training and detraining in young men. Eur J Appl Physiol. 2001; 85: 259-263
• 34 Michael S, Jay O, Graham KS, Davis GM. Longer exercise duration delays post-exercise recovery of cardiac parasympathetic but not sympathetic indices. Eur J Appl Physiol 2017; 117: 1897-1906
• 35 Goodwin ML, Harris JE, Hernaindez A, Gladden LB. Blood lactate measurements and analysis during exercise: A guide for clinicians. J Diabetes Sci Technol 2007; 1: 558-569
• 36 Borg E, Borg G. A comparison of AME and CR100 for scaling perceived exertion. Acta Psychol (Amst) 2002; 109: 157-175
• 37 Buchheit M, Laursen PB, Ahmaidi S. Parasympathetic reactivation after repeated sprint exercise. Am J Physiol Heart Circ Physiol 2007; 293: H133-H141
• 38 Pecanha T, Bartels R, Brito LC, Paula-Ribeiro M, Oliveira RS, Goldberger JJ. Methods of assessment of the post-exercise cardiac autonomic recovery: A methodological review. Int J Cardiol 2017; 227: 795-802
• 39 Bakdash JZ, Marusich LR. Repeated measures correlation. Front Psychol 2017; 8: 456
• 40 Oliveira ALMB, Rohan P de A, Gonçalves TR, Soares PP da S, Oliveira ALMB, Rohan P de A, Gonçalves TR, Soares PP da S. Effects of hypoxia on heart rate variability in healthy individuals: A systematic review. Int J Cardiovasc Sci 2017; 30: 251-261
• 41 Buchheit M, Richard R, Doutreleau S, Lonsdorfer-Wolf E, Brandenberger G, Simon C. Effect of acute hypoxia on heart rate variability at rest and during exercise. Int J Sports Med 2004; 25: 264-269
• 42 White DW, Raven PB. Autonomic neural control of heart rate during dynamic exercise: revisited. J Physiol 2014; 592: 2491-2500
• 43 Terziotti P, Schena F, Gulli G, Cevese A. Post-exercise recovery of autonomic cardiovascular control: a study by spectrum and cross-spectrum analysis in humans. Eur J Appl Physiol. 2001; 84: 187-194
• 44 Goldberger JJ, Le FK, Lahiri M, Kannankeril PJ, Ng J, Kadish AH. Assessment of parasympathetic reactivation after exercise. Am J Physiol Heart Circ Physiol 2006; 290: H2446-H2452
• 45 Romero SA, Minson CT, Halliwill JR. The cardiovascular system after exercise. J Appl Physiol (1985) 2017; 122: 925-932
• 46 Fisher JP, Adlan AM, Shantsila A, Secher JF, Sørensen H, Secher NH. Muscle metaboreflex and autonomic regulation of heart rate in humans. J Physiol. 2013; 591: 3777-3788
• 47 Peçanha T, de Brito LC, Fecchio RY, de Sousa PN, da Silva Junior ND, de Abreu AP, da Silva GV, Mion-Junior D, Forjaz CL de M. Metaboreflex activation delays heart rate recovery after aerobic exercise in never-treated hypertensive men. J Physiol 2016; 594: 6211-6223
• 48 Fisher JP. Autonomic control of the heart during exercise in humans: role of skeletal muscle afferents. Exp Physiol 2014; 99: 300-305
• 49 Aliverti A, Kayser B, Mauro A Lo, Quaranta M, Pompilio P, Dellacà RL, Ora J, Biasco L, Cavalleri L, Pomidori L, Cogo A, Pellegrino R, Miserocchi G. Respiratory and leg muscles perceived exertion during exercise at altitude. Respir Physiol Neurobiol 2011; 177: 162-168