No relationship exists between urinary NT-proBNP and GPS technology in professional rugby union.
OBJECTIVE
We investigated the level of cardiovascular stress associated with professional rugby union and whether these changes could be explained through external workload systems like GPS and video analysis.


METHODS
Urine samples (14 in game one and 13 in game two) were collected from professional rugby players before, immediately post- and 36h post-play in two consecutive games.


METHODS
Urine was analysed for NT-proBNP by ELISA. Comparison with GPS (player-load and distance covered at specific speed bands) and video analysis (total impacts) were conducted.


RESULTS
There was a significant increase in urinary NT-proBNP during game one (31.6±5.4 to 53.5±10.8pg/mL) and game two (35.4±3.9 to 49.8±11.7pg/mL) that did not correlate with the number of impacts, total distance covered, distance covered at pre-determined speed bands or player-load. Concentrations returned to pre-game concentrations 36h post-game whilst a large inter-individual variation in NT-proBNP was observed among players (p<0.001).


CONCLUSIONS
Professional rugby union causes a transient increase in cardiovascular stress that seems to be independent of the external workload characteristics of a player.
Free Radical Biochemistry Laboratory, School of Biological Sciences, University of Canterbury, New Zealand; Department of Rehabilitation Medicine, University of Minnesota, USA. Electronic address: Authorsanguslindsay@outlook.com.
Angus
A
Lindsay
Steroid and Immunobiochemistry Laboratory, Canterbury Health Laboratories, New Zealand.
John G
JG
Lewis
New Zealand Rugby Union, New Zealand; Sports Performance Research Institute New Zealand, School of Sport and Recreation, Auckland University of Technology, New Zealand.
Nicholas
N
Gill
College of Life and Natural Sciences, University of Derby, United Kingdom.
Nick
N
Draper
Free Radical Biochemistry Laboratory, School of Biological Sciences, University of Canterbury, New Zealand; Department of Radiology, University of Otago, New Zealand.
Steven P
SP
Gieseg
D000328:Adult; D054874:Athletic Performance / Q000502:physiology*; D015415:Biomarkers / Q000652:urine; D004797:Enzyme-Linked Immunosorbent Assay; D005538:Football / Q000502:physiology*; D040362:Geographic Information Systems; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000652:urine*; D010446:Peptide Fragments / Q000652:urine*; D012420:Running / Q000502:physiology; D013312:Stress, Physiological / Q000502:physiology*; D055815:Young Adult
D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
Cardiovascular/cardiorespiratory; Exercise; Game analysis; Team sport