Single and Repeat Ischemic Preconditioning Unable to Modify Cold Induced Vasodilation or Cold Air Finger Skin Temperatures and Manual Dexterity

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) prior to cold exposure to 1) improve peripheral skin temperatures, blood flow and manual dexterity during 90 minutes of 0°C cold air exposure with exposed hands (CA), 2) enhance the cold induced vasodilation (CIVD) response to 30 minutes 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 x 5 minutes occlusion/5 minutes of reperfusion on the dominant arm. No dose of IPC, performed prior to cold tests, improved hand or finger skin temperatures, skin blood flow, manual dexterity, or thermal perceptions across 90 minutes spent in 0°C CA. No change in any CIVD or immediate rewarming parameter was demonstrated with IPC versus control. IPC5 improved non-dominant hand thermal sensations compared to CON immediately upon immersion in 8°C water (median (min-max; IPC5: -2 (-3 to -1) au, CON: -3 (-4 to -1) au, <i>p</i>= 0.045), with a similar trend in the dominant hand. Overall, neither one cycle of 4 x 5 min IPC nor 5 consecutive days of 4 x 5 min IPC appears capable of improving manual dexterity performance in 0°C cold air or indices of cold induced vasodilation.