Single and repeat ischemic preconditioning unable to modify cold-induced vasodilation or cold air finger skin...

Cold-induced peripheral vasoconstriction reduces skin blood flow, skin temperatures, and manual dexterity. This study proposed the use of single and repeated ischemic preconditioning (IPC) before cold exposure to 1) improve peripheral skin temperatures, blood flow, and manual dexterity during 90 min of 0°C cold air exposure with exposed hands cold air (CA); 2) enhance the cold-induced vasodilation (CIVD) response to 30 min of 8°C dual-hand water immersion and rewarming (CWI); and 3) improve thermal perceptions during both exposures. Seventeen volunteers (16 males, 1 female) completed a repeated trial design: 1) CON, no IPC; 2) IPC1_A, one 40-min IPC procedure; 3) IPC5, five consecutive days of IPC; and 4) IPC1_B, one IPC procedure. Single IPC consisted of 4 × 5 min occlusion/5 min of reperfusion on the dominant arm. No dose of IPC, performed before cold tests, improved hand or finger skin temperatures, skin blood flow, manual dexterity, or thermal perceptions across 90 min spent in 0°C CA. No change in any CIVD or immediate rewarming parameter was demonstrated with IPC versus control. IPC5 improved nondominant hand thermal sensations compared with CON immediately upon immersion in 8°C water [median (min-max); IPC5: -2 (-3 to -1) arbitrary units (au), CON: -3 (-4 to -1) au, P = 0.045], with a similar trend in the dominant hand. Overall, neither one cycle of 4 × 5 min IPC nor five consecutive days of 4 × 5 min IPC appear capable of improving manual dexterity performance in 0°C cold air or indices of cold-induced vasodilation.NEW & NOTEWORTHY This investigation provides novel evidence that neither single nor repeated ischemic preconditioning can improve the neural cold-induced vasodilation response to cold water, augment cold water rewarming responses, or elevate hand and finger skin temperatures, skin blood flow, or manual dexterity in cold air.