The effect of different types of exercise on the prevention of ischaemia-reperfusion injury: a pilot study

Exercise training has strong cardioprotective effects in asymptomatic subjects
as well as those with established cardiovascular risk and/or disease.
Ischaemia-reperfusion (IR) represents a significant and harmful stimulus for
tissues, including the myocardium and the vascular endothelium. Recent studies
have found preliminary evidence that exercise training is associated with a
reduced endothelial IR-injury, which may partly contribute to the protective
effects of exercise training. Possibly, acute bouts of exercise possess the
ability to prevent endothelial IR injury in humans in vivo.
Recent studies have demonstrated that different types of exercise training
possess different effects, with high-intensity interval training leading to
superior effects on physical fitness and the vasculature compared to
*traditional* continuous moderate-intensity exercise. Accordingly, different
types of exercise may have a distinct impact on the ability to prevent
endothelial IR injury. Such protection through exercise would be similar as
observed with ischaemic preconditioning; i.e. a validated and successful method
to prevent endothelial IR-injury. Ischaemic preconditioning is typically
applied locally to the forearm. This raises the question whether local
(forearm) exercise may be sufficient to induce systemic protective effects.
This is highly relevant since whole body training is a demanding type of
exercise, which might be difficult to implement in clinical setting. Local,
handgrip exercise, however, would be more feasible to implement in clinical
settings to reduce IR-injury.

To explore the impact of different types (high-intensity vs moderate-intensity
cycling), modes (whole bodycycling vs local handgrip) and stimuli (exercise vs
ischaemic) of preconditioning on the ability to protect endothelial damage in
response to ischaemia reperfusion injury in healthy humans. A secondary
objective is to explore the potential mechanisms by which preconditioning
elicits the beneficial effects on IR-injury.

explorative randomized cross-over trial

Three sessions of 30-min exercise (high intensity cycling, moderate intensity
cycling, handgrip exercise), single session of ischaemic preconditioning, and a
control session.

Non-invasive cuff occlusion is used to examine endothelial function (5-minute
ischaemia) and produce the stimulus that induces ischaemia-reperfusion injury
(15-minute ischaemia). Cuff inflation is non-invasive and not associated with a
health risk for the subject. Also exercise is not associated with a significant
health risk in our participants. Blood will be drawn three times per testing
day for ex-vivo analysis. The volunteers will not benefit directly from
participating in this study.