Manipulating graded exercise test variables affects the validity of the lactate threshold and V˙O2peak

Abstract

The data highlight how GXT protocol design and data analysis influence the determination of both <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>˙</mml:mo> </mml:mover> <mml:mo>⁢</mml:mo> <mml:mi mathvariant="normal">O</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> <mml:mo>⁢</mml:mo> <mml:mi mathvariant="normal">peak</mml:mi> </mml:mrow> </mml:msub> </mml:mrow> </mml:math> and LT. It is also apparent that <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mrow> <mml:mover accent="true"> <mml:mi mathvariant="normal">V</mml:mi> <mml:mo>˙</mml:mo> </mml:mover> <mml:mo>⁢</mml:mo> <mml:mi mathvariant="normal">O</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> <mml:mo>⁢</mml:mo> <mml:mi mathvariant="normal">max</mml:mi> </mml:mrow> </mml:msub> </mml:mrow> </mml:math> and LT cannot be determined in a single GXT, even with the inclusion of a VEB.