title: Metabolic and cardiorespiratory responses relative to the anaerobic threshold.
abstract: The present study has compared the metabolic and cardiorespiratory responses for two groups of male subjects during 20 min of exercise at the anaerobic threshold (AT), at AT + 1/3, and at AT + 2/3 of the difference (delta) between AT and VO2max. A log-log transformation of the lactate (LA)-power output relationship was used to define AT and divide subjects into a high (N = 7, AT = 51.9 +/- 1.5% VO2max) and low (N = 5; AT = 41.9 +/- 1.8% VO2max) AT group. No differences were observed between groups during exercise at AT for VE.VO2-(1), VE.VCO2(-1), pH, pCO2, blood LA, and plasma strong ions Na+, K+, and Cl-. Although blood LA values were significantly elevated for the low AT subjects (2.3 +/- 0.6 mmol.l-1) compared with the high AT group (1.0 +/- 0.1 mmol.l-1) during exercise at AT + 1/3 delta, no other differences between groups were noted. In contrast, marked differences were observed between groups during exercise at AT + 2/3 delta. The high AT group showed no change in VE (79.1 +/- 4.8 l.min-1), pH (7.367 +/- 0.01), pCO2 (37.3 +/- 1.2 mm Hg), and blood LA (2.9 +/- 0.3 mmol.l-1) during the final 10 min of the 20 min exercise test.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Biological Sciences, Cumberland College of Health Sciences, New South Wales, Australia.
authors.forename: T M
authors.initials: TM
authors.lastname: McLellan
authors.forename: G C
authors.initials: GC
authors.lastname: Gass
mesh_terms: D000136:Acid-Base Equilibrium; D000328:Adult; D015308:Anaerobic Threshold; D015444:Exercise; D005221:Fatigue / Q000097:blood; D006339:Heart Rate; D006801:Humans; D007773:Lactates / Q000097:blood*; D019344:Lactic Acid; D008297:Male; D010101:Oxygen Consumption; D011659:Pulmonary Gas Exchange; D013997:Time Factors
chemical_list: D007773:Lactates; D019344:Lactic Acid