Localised cutaneous microvascular adaptation to exercise training in humans

Area of Science:

• Physiology
• Exercise Science
• Vascular Biology

Background:

• Exercise training impacts blood vessels, but cutaneous microvascular adaptations are less understood.
• Previous research focused on conduit and resistance arteries, not skin microvasculature.
• The role of exercise-induced stimuli on skin microvascular function requires further investigation.

Purpose of the Study:

• To investigate the intrinsic cutaneous microvascular adaptations to exercise training.
• To determine if exercise training alters skin microvascular responses to local heating.
• To explore the role of exercise-induced blood flow and shear stress in cutaneous adaptation.

Main Methods:

• 14 healthy young men underwent 8 weeks of cycle ergometer training.
• One forearm had cuff inflation to attenuate cutaneous blood flow during exercise.
• Forearm skin microvascular dilation was assessed via cutaneous vascular conductance (CVC) responses to local heating before and after training.

Main Results:

• Cycle exercise increased forearm skin blood flow and temperature, but this was blunted in the cuffed arm.
• Following training, forearm CVC responses to local heating (42°C and 44°C) were significantly lower in the uncuffed arm.
• No significant changes in CVC were observed in the cuffed arm, indicating a localized adaptation.

Conclusions:

• Lower limb exercise training in young men reduces cutaneous vascular conductance responses to local heating.
• This adaptation is partly mediated by increased skin blood flow and/or skin temperature during exercise.
• Exercise-induced changes in shear stress may play a role in cutaneous microvascular adaptation.