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We wanted to determine the influence of total blood volume (BV) and blood lactate quantity on lactate concentrations during incremental exercise. Twenty-six healthy, nonsmoking, heterogeneously trained females (27.5 ± 5.9 ys) performed an incremental cardiopulmonary exercise test on a cycle ergometer during which maximum oxygen uptake (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mover><mi mathvariant="normal">V</mi><mo>·</mo></mover></mrow></semantics></math></inline-formula>O_2max), lactate concentrations ([La⁻]) and hemoglobin concentrations ([Hb]) were determined. Hemoglobin mass and blood volume (BV) were determined using an optimised carbon monoxide-rebreathing method. <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mover><mi mathvariant="normal">V</mi><mo>·</mo></mover></mrow></semantics></math></inline-formula>O_2max and maximum power (P_max) ranged between 32 and 62 mL·min⁻¹·kg⁻¹ and 2.3 and 5.5 W·kg⁻¹, respectively. BV ranged between 81 and 121 mL·kg⁻¹ of lean body mass and decreased by 280 ± 115 mL (5.7%, <i>p</i> = 0.001) until P_max. At P_max, the [La⁻] was significantly correlated to the systemic lactate quantity (La⁻, r = 0.84, <i>p</i> < 0.0001) but also significantly negatively correlated to the BV (r = −0.44, <i>p</i> < 0.05). We calculated that the exercise-induced BV shifts significantly reduced the lactate transport capacity by 10.8% (<i>p</i> < 0.0001). Our results demonstrate that both the total BV and La⁻ have a major influence on the resulting [La⁻] during dynamic exercise. Moreover, the blood La⁻ transport capacity might be significantly reduced by the shift in plasma volume. We conclude, that the total BV might be another relevant factor in the interpretation of [La⁻] during a cardio-pulmonary exercise test.