TY - JOUR

T1 - Central and peripheral hemodynamics in exercising humans

T2 - leg vs arm exercise

AU - Calbet, J A L

AU - González-Alonso, J

AU - Helge, J W

AU - Søndergaard, H

AU - Munch-Andersen, T

AU - Saltin, B

AU - Boushel, R

N1 - © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

PY - 2015

Y1 - 2015

N2 - In humans, arm exercise is known to elicit larger increases in arterial blood pressure (BP) than leg exercise. However, the precise regulation of regional vascular conductances (VC) for the distribution of cardiac output with exercise intensity remains unknown. Hemodynamic responses were assessed during incremental upright arm cranking (AC) and leg pedalling (LP) to exhaustion (Wmax) in nine males. Systemic VC, peak cardiac output (Qpeak) (indocyanine green) and stroke volume (SV) were 18%, 23%, and 20% lower during AC than LP. The mean BP, the rate-pressure product and the associated myocardial oxygen demand were 22%, 12%, and 14% higher, respectively, during maximal AC than LP. Trunk VC was reduced to similar values at Wmax. At Wmax, muscle mass-normalized VC and fractional O2 extraction were lower in the arm than the leg muscles. However, this was compensated for during AC by raising perfusion pressure to increase O2 delivery, allowing a similar peak VO2 per kg of muscle mass in both extremities. In summary, despite a lower Qpeak during arm cranking the cardiovascular strain is much higher than during leg pedalling. The adjustments of regional conductances during incremental exercise to exhaustion depend mostly on the relative intensity of exercise and are limb-specific.

AB - In humans, arm exercise is known to elicit larger increases in arterial blood pressure (BP) than leg exercise. However, the precise regulation of regional vascular conductances (VC) for the distribution of cardiac output with exercise intensity remains unknown. Hemodynamic responses were assessed during incremental upright arm cranking (AC) and leg pedalling (LP) to exhaustion (Wmax) in nine males. Systemic VC, peak cardiac output (Qpeak) (indocyanine green) and stroke volume (SV) were 18%, 23%, and 20% lower during AC than LP. The mean BP, the rate-pressure product and the associated myocardial oxygen demand were 22%, 12%, and 14% higher, respectively, during maximal AC than LP. Trunk VC was reduced to similar values at Wmax. At Wmax, muscle mass-normalized VC and fractional O2 extraction were lower in the arm than the leg muscles. However, this was compensated for during AC by raising perfusion pressure to increase O2 delivery, allowing a similar peak VO2 per kg of muscle mass in both extremities. In summary, despite a lower Qpeak during arm cranking the cardiovascular strain is much higher than during leg pedalling. The adjustments of regional conductances during incremental exercise to exhaustion depend mostly on the relative intensity of exercise and are limb-specific.

KW - Adult

KW - Arm

KW - Arterial Pressure

KW - Exercise

KW - Exercise Test

KW - Heart

KW - Hemodynamics

KW - Humans

KW - Leg

KW - Male

KW - Middle Aged

KW - Muscle, Skeletal

KW - Oxygen

KW - Physical Exertion

KW - Regional Blood Flow

KW - Stroke Volume

KW - Vascular Resistance

KW - Young Adult

KW - Comparative Study

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1111/sms.12604

DO - 10.1111/sms.12604

M3 - Journal article

C2 - 26589128

VL - 25

SP - 144

EP - 157

JO - Scandinavian Journal of Medicine & Science in Sports

JF - Scandinavian Journal of Medicine & Science in Sports

SN - 0905-7188

IS - Suppl 4

ER -