title: Identification of anaerobic threshold by analysis of heart rate variability during discontinuous dynamic and resistance exercise protocols in healthy older men.
abstract: The purposes of this study were to determine anaerobic threshold (AT) during discontinuous dynamic and resistive exercise protocols by analysing of heart rate variability (HRV) and blood lactate (BL) in healthy elderly subjects and compare the cardiovascular, metabolic and autonomic variables obtained from these two forms of exercise. Fourteen elderly (70 ± 4 years) apparently healthy males underwent the following tests: (i) incremental ramp test on cycle ergometer, (ii) one repetition maximum (1RM) leg press at 45°, (iii) a discontinuous exercise test on a cycle ergometer (DET-C) protocol and (iv) a resistance exercise leg press (DET-L) protocol. Heart rate, blood pressure and BL were obtained during each increment of exercise intensity. No significant differences (P>0·05) were found between methods of AT determination (BL and HRV) nor the relative intensity corresponding to AT (30% of maximum intensity) between the types of exercise (DET-C and DET-L). Furthermore, no significant differences (P>0·05) were found between the DET-C and DET-L in relation to HRV, however, the DET-L provided higher values of systolic blood pressure and BL (P<0·05) from the intensity corresponding to AT. We conclude that HRV was effective in determination of AT, and the parasympathetic modulation responses obtained during dynamic and resistive exercise protocols were similar when compared at the same relative intensity. However, DET-L resulted in higher values of blood pressure and BL at workloads beyond AT.
authors.affiliation: Cardiopulmonary Physiotherapy Laboratory, Nucleus of Research in Physical Exercise of Federal University of Sao Carlos, Sao Carlos, SP, Brazil.
authors.forename: Rodrigo Polaquini
authors.initials: RP
authors.lastname: Simões
authors.forename: Viviane
authors.initials: V
authors.lastname: Castello-Simões
authors.forename: Renata Gonçalves
authors.initials: RG
authors.lastname: Mendes
authors.forename: Bruno
authors.initials: B
authors.lastname: Archiza
authors.forename: Daniel Augusto
authors.initials: DA
authors.lastname: Dos Santos
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Bonjorno
authors.forename: Claudio Ricardo
authors.initials: CR
authors.lastname: de Oliveira
authors.forename: Aparecida Maria
authors.initials: AM
authors.lastname: Catai
authors.forename: Ross
authors.initials: R
authors.lastname: Arena
authors.forename: Audrey
authors.initials: A
authors.lastname: Borghi-Silva
mesh_terms: D000222:Adaptation, Physiological; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000378:metabolism*; D015308:Anaerobic Threshold; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D005080:Exercise Test; D064368:Healthy Volunteers; D006339:Heart Rate; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000378:metabolism*; D055070:Resistance Training; D013997:Time Factors
chemical_list: D015415:Biomarkers; D019344:Lactic Acid
keywords: aerobic training; ageing; autonomic nervous system; lactate threshold; resistance training