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A combination of sympathoexcitation and vagal withdrawal increases heart rate (HR) during exercise, however, their specific contribution to arterial baroreflex sensitivity remains unclear. Eight subjects performed 25 min bouts of exercise at a HR of 90, 120, and 150 beats min⁻¹, respectively, with and without metoprolol (0.16 ± 0.01 mg kg⁻¹; mean ±s.e.m.) or glycopyrrolate (12.6 ± 1.6 μg kg⁻¹). Carotid baroreflex (CBR) function was determined using 5 s pulses of neck pressure (NP) and neck suction (NS) from +40 to −80 Torr, while transfer function gain (G_TF) was calculated to assess the linear dynamic relationship between mean arterial pressure and HR. Spontaneous baroreflex sensitivity (SBR) was evaluated as the slope of sequences of three consecutive beats in which systolic blood pressure and the R–R interval of the ECG either increased or decreased, in a linear fashion. The β‐1 adrenergic blockade …