Preliminary study on the effect of sex on skin cooling response during whole body cryostimulation (-110 °C): Modeling and prediction of exposure durations

Partial-body cryostimulation does not impact peripheral microvascular responsiveness but reduces muscular metabolic O2 consumption (mV˙O2) at rest

This study aimed to investigate the effect of partial-body cryostimulation (PBC) on microvascular responsiveness and muscular metabolic O2 consumption rate (mV˙O2). Twenty healthy young adults (ten males and ten females) underwent a post-occlusive reactive hyperemia (PORH) test at the flexor digitorum superficialis area before and after a 3-min PBC session and a 3-min control session. Using near-infrared spectroscopy, occlusion and reperfusion slopes were calculated: oxyhemoglobin ([HbO2]) decrease rate ([HbO2] slope 1), deoxyhaemoglobin ([HHb]) increase rate ([HHb] slope 1), [HbO2] increase rate ([HbO2] slope 2), and [HHb] increase rate ([HHb] slope 2. Using HbO2 kinetics during the occlusion, mV˙O2 was also calculated to characterize myocytes' metabolic O2 consumption. HbO2 slope 1 value was lower after PBC than before PBC (-0.15 ± 0.08 vs -0.24 ± 0.11 s-1; respectively; P < 0.05) in male participants only. A lower [HHb] slope 1 was also observed after PBC compared to before PBC (0.18 ± 0.10 vs 0.24 ± 0.16 s-1; P < 0.05) with no interaction for sex categories. mV˙O2 was significantly lower after PBC than before (pre values 14.75 ± 3.94 vs 18.47 ± 5.73 μMO2Hb.s-1; respectively; P < 0.01) with no interaction between sex categories. No changes in the calculated slope 2 were observed. These findings suggest that a single session of PBC reduces the muscular metabolic O2 needs at rest; however, it does not alter the vascular ability to provide O2 to the myocytes.

Cryostimulation for Post-exercise Recovery in Athletes: A Consensus and Position Paper

Recovery after exercise is a crucial key in preventing muscle injuries and in speeding up the processes to return to homeostasis level. There are several ways of developing a recovery strategy with the use of different kinds of traditional and up-to-date techniques. The use of cold has traditionally been used after physical exercise for recovery purposes. In recent years, the use of whole-body cryotherapy/cryostimulation (WBC; an extreme cold stimulation lasting 1-4 min and given in a cold room at a temperature comprised from -60 to -195°C) has been tremendously increased for such purposes. However, there are controversies about the benefits that the use of this technique may provide. Therefore, the main objectives of this paper are to describe what is whole body cryotherapy/cryostimulation, review and debate the benefits that its use may provide, present practical considerations and applications, and emphasize the need of customization depending on the context, the purpose, and the subject's characteristics. This review is written by international experts from the working group on WBC from the International Institute of Refrigeration.