Vagal Threshold Determination. Effect of Age and Gender

Abstract

Progressive increases in exercise intensity cause significant decreases in vagal activity (VA) until a critical point called the vagal threshold (TVA) is reached. This is where further increases in exercise intensity cause negligible change in VA. This study was designed to develop the algorithm for the TVA determination and to assess the effects of age and gender on its level. The sample consisted of 40 subjects who were divided according to age and gender into 4 groups with 10 subjects each: G1-Men age 25–31, G2-Men age 40–57, G3-Women age 24–28, and G4-Women age 43–56. The vagal responses were assessed by spectral analysis of the heart rate variability method while walking on a treadmill in a steady-state at intensities of 20–70% of the maximal heart rate reserve (MHRR). The mean intensity of 45% MHRR was suggested as the TVA level which is related neither to age nor gender. Heart rate related to TVA (TVA-HR) was affected by gender. High frequency power at TVA was influenced by age. The TVA-HR was considered to be a promising tool for the prescription of a safe level of physical activity for subjects with higher risks of health complications involving elevated sympathoadrenal activity during exercise.

parasympathetic activity - spectral analysis of heart rate variability - exercise intensity

References

• 1 Akselrod S, Gordon D, Ubel FA, Shannon DC, Berger AC, Cohen RJ. Power spectrum analysis of heart rate fluctuation: a quantitative probe of beat-to-beat cardiovacular control.  Science. 1981;  213 220-222
• 2 Billman GE. Cardiac autonomic neural remodeling and susceptibility to sudden cardiac death: effect of endurance exercise training.  Am J Physiol. 2009;  297 H1171-H1193
• 3 Buch AN, Coote JH, Townend JN. Mortality, cardiac vagal control and physical training – what's the link?.  Exp Physiol. 2002;  87 423-435
• 4 Cottin F, Médigue C, Papelier Y. Effect of heavy exercise on spectral baroreflex sensitivity, heart rate, and blood pressure variability in well-trained humans.  Am J Physiol. 2008;  295 H1150-H1155
• 5 De Meersman RE, Stein PK. Vagal modulation and aging.  Biol Psychol. 2007;  74 165-173
• 6 González-Camarena R, Carrasco-Sosa S, Román-Ramos R, Gaitán-González MJ, Medina-Bañuelos V, Azpiroz-Leehan J. Effect of static and dynamic exercise on heart rate and blood pressure variabilities.  Med Sci Sports Exerc. 2000;  32 1719-1728
• 7 Harriss DJ, Atkinson G. International Journal of Sports Medicine – Ethical Standards in Sport and Exercise Science Research.  Int J Sports Med. 2009;  30 701-702
• 8 Hautala AJ, Mäkikallio TH, Seppänen T, Huikuri HV, Tulppo MP. Short-term correlation properties of R-R interval dynamics at different exercise intensity levels.  Clin Physiol Funct Imaging. 2003;  23 215-223
• 9 Christou DD, Seals DR. Decreased maximal heart rate with aging is related to reduced {beta}-adrenergic responsiveness but is largely explained by a reduction in intrinsic heart rate.  J Appl Physiol. 2008;  105 24-29
• 10 Karvonen MJ, Kentala E, Mustala O. The effects of training on heart rate; a longitudinal study.  Ann Med Exp Biol Fenn. 1957;  35 307-315
• 11 Kostis JB, Moreyra AE, Amendo MT, Di Pietro J, Cosgrove N, Kuo PT. The effect of age on heart rate in subjects free of heart disease. Studies by ambulatory electrocardiography and maximal exercise stress test.  Circulation. 1982;  65 141-145
• 12 Kuga K, Yamaguchi I, Sugushita Y. Age-related changes of sinus node function and autonomic regulation in subjects without sinus node disease. Assessment by pharmacological blockade.  Jpn Circ J. 1993;  57 760-768
• 13 Lee K, Picard G, Beske SD, Hwang GS, Taylor JA. Effects of fitness and age on the response to vagotonic atropine.  Auton Neurosci. 2008;  139 60-67
• 14 Perini R, Veicsteinas A. Heart rate variability and autonomic activity at rest and during exercise in various physiological conditions.  Eur J Appl Physiol. 2003;  90 317-325
• 15 Robinson BF, Epstein SE, Beiser GD, Braunwald E. Control of heart rate by the autonomic nervous system. Studies in man on the interrelation between baroreceptor mechanisms and exercise.  Circ Res. 1966;  19 400-411
• 16 Salinger J, Gwozdziewicz M. Systémy pouŽívané pro vyšetøení krátkodobé variability srdeèní frekvence. In: Javorka K (ed). Variabilita frekvencie srdca: Mechanismy, hodnotenie, klinické vyuŽitie. Martin: Osveta; 2008: 57-60
• 17 Shibata M, Moritani T, Miyawaki T, Hayashi T, Nakao K. Exercise prescription based upon cardiac vagal activity for middle-aged obese women.  Int J Obes Relat Metab Disord. 2002;  26 1356-1362
• 18 Stejskal P, Rechbergova J, Salinger J, Šlachta R; Elfmark M, Kalina M, Jurèa R, Řehová I. Power spectrum of heart rate variability in exercising humans: The effect of exercise intensity.  Sports Med Training Rehab. 2001;  10 39-57
• 19 Sztajzel J, Jung M, Bayes de Luna A. Reproducibility and gender-related differences of heart rate variability during all-day activity in young men and women.  Ann Noninvasive Electrocardiol. 2008;  13 270-277
• 20 Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology . Heart rate variability: Standards of measurement, physiological interpretation and clinical use.  Circulation. 1996;  93 1043-1065
• 21 Tulppo PM, Mäkikallio HT, Seppnen T, Laukkanen TR, Huikuri VH. Vagal modulation of heart rate during exercise: Effects of age and physical fitness.  Am J Physiol. 1998;  274 H424-H429
• 22 Vanoli E, Adamson PB, Hull Jr SS, Foreman RD, Schwartz PJ. Prediction of unexpected sudden death among healthy dogs by a novel marker of autonomic neural activity.  Heart Rhythm. 2008;  5 300-305
• 23 Vincent WJ. Statistics in Kinesiology. Champaing IL: Human Kinetics; 1995: 178-180
• 24 Warren JH, Jaffe RS, Wraa CE, Stebbins CL. Effect of autonomic blockade on power spectrum of heart rate variability during exercise.  Am J Physiol. 1997;  273 495-502
• 25 Yamamoto Y, Hughson RL. Coarse-graining spectral analysis: new method for studying heart rate variability.  J Appl Physiol. 1991;  71 1143-1150

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