title: The effect of a sleep high-train low regimen on the finger cold-induced vasodilation response.
abstract: The present study evaluated the effect of a sleep high-train low regimen on the finger cold-induced vasodilation (CIVD) response. Seventeen healthy males were assigned to either a control (CON; n=9) or experimental (EXP; n=8) group. Each group participated in a 28-day aerobic training program of daily 1-h exercise (50% of peak power output). During the training period, the EXP group slept at a simulated altitude of 2800 meters (week 1) to 3400 m (week 4) above sea level. Normoxic (CIVD(NOR); CON and EXP groups) and hypoxic (CIVD(HYPO); F(I)O(2)=0.12; EXP group only) CIVD characteristics were assessed before and after the training period during a 30-min immersion of the hand in 8°C water. After the intervention, the EXP group had increased average finger skin temperature (CIVD(NOR): +0.5°C; CIVD(HYPO): +0.5°C), number of waves (CIVD(NOR): +0.5; CIVD(HYPO): +0.6), and CIVD amplitude (CIVD(NOR): +1.5°C; CIVD(HYPO): +3°C) in both CIVD tests (p<0.05). In contrast, the CON group had an increase in only the CIVD amplitude (+0.5°C; p<0.05). Thus, the enhancement of aerobic performance combined with altitude acclimatization achieved with the sleep high-train low regimen contributed to an improved finger CIVD response during cold-water hand immersion in both normoxic and hypoxic conditions.
authors.affiliation: Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia. mojca.amon@gmail.com
authors.forename: Mojca
authors.initials: M
authors.lastname: Amon
authors.forename: Michail E
authors.initials: ME
authors.lastname: Keramidas
authors.forename: Stylianos N
authors.initials: SN
authors.lastname: Kounalakis
authors.forename: Igor B
authors.initials: IB
authors.lastname: Mekjavic
mesh_terms: D000064:Acclimatization; D000531:Altitude; D000704:Analysis of Variance; D015444:Exercise / Q000502:physiology*; D005385:Fingers / Q000098:blood supply* / Q000502:physiology; D006339:Heart Rate; D006801:Humans; D007036:Hypothermia, Induced; D008297:Male; D010101:Oxygen Consumption; D005082:Physical Exertion; D012881:Skin Temperature; D012890:Sleep / Q000502:physiology*; D018709:Statistics, Nonparametric; D014664:Vasodilation