title: The validity of physiological variables to assess training intensity in kayak athletes.
abstract: It appears that training benefits are compromised if excessive training is performed at intensities that are either too low or too high. This suggests a need for accurate methods to monitor training intensity. It has been suggested that heart rate (HR) or lactate concentration ([La -]) can be used to accurately monitor training intensity. The purpose of the present study therefore, was to examine whether the relationship between HR, [La -] and intensity determined during a kayak graded exercise test (GXT) remained stable during constant-intensity kayak exercise. Sixteen trained kayak paddlers, (22 +/- 4 y, peak V.O (2) = 3.7 +/- 0.9 l x min (-1)) performed a GXT on a wind-braked kayak ergometer. They then performed a 20-min constant-load test on the kayak ergometer at a power output corresponding to their lactate inflection (LI) intensity. Eight subjects also performed a 20-min constant-load test at a power output corresponding to their lactate threshold (LT) intensity. Differences between constant-load and GXT values were determined using one-way ANOVA (p < 0.05). There were no significant differences between values for HR and V.O (2) derived from the GXT and those measured during both constant-load tests. However, while [La -] also provided a valid marker of the LI training intensity (1.8 +/- 0.3 v 2.1 +/- 0.8 mmol x l (-1)), [La -] did not provide a valid marker of the LT training intensity (3.8 +/- 0.7 v 5.1 +/- 1.4 mmol x l (-1)). These results suggest that HR, but not [La -1], is similar during both a GXT and constant-load exercise at the LT intensity.
authors.affiliation: School of Human Movement and Exercise Science, University of Western Australia, Crawley, WA 6009, Australia. dbishop@cyllene.uwa.edu.au
authors.forename: D
authors.initials: D
authors.lastname: Bishop
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007773:Lactates / Q000097:blood*; D008297:Male; D008991:Monitoring, Physiologic; D010806:Physical Education and Training; D010809:Physical Fitness / Q000502:physiology*; D011659:Pulmonary Gas Exchange; D013177:Sports / Q000502:physiology*
chemical_list: D007773:Lactates