A single session of whole-body cryotherapy boosts maximal cycling performance and enhances vagal drive at rest

Figures

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  Fig. 1. Experimental procedure. Timeline of the experiment is shown in panel a The three experimental days are described: maximal power measurement day (POW day), control evaluation day (CTR day) and post-cryotherapy evaluation day (WBC day). Black vertical bars mark the 3–5 days interval between experimental sessions. In color, the different experimental phases: 3 min warm-up, pink (w-up); maximal exercise, red (all-out); 10 min rest on bed, green; 5 min recovery, orange (recov); 3 min whole body cryotherapy, blue (WBC). Braces mark the time windows in which either the heart rate variability (HRV) or the heart rate recovery parameters (HRrec) were measured. Panel b illustrates the time course of the heart rate (HR) in a representative subject, recorded in CTR day. HR kinetics at rest before exercise (PRE, last 5 min), during exercise (EXE, maximal cycling from blue arrow to 0 s and recovery from 0 to 300 s), and at post-exercise rest (POST, last 5 min). In EXE, the thick vertical line represents the end of exercise while the dashed line indicates the onset of the HR exponential decay; thus, timing between these two lines marks tDELAY (dots in red). The red vertical bar marks τOFF, i.e.…

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  Fig. 2. HRV analysis. LFnu, measured when lying supine on bed, is plotted in panel a All-out exercise significantly increased this parameter (POST vs. PRE) both in CTR condition (red line) and after WBC (blue). Instead, WBC significantly lowered LFnu, inducing a similar decrease both before and after exercise (CTR – WBC in PRE vs. CTR – WBC in POST). Panels b and c describe the effects of exercise and WBC on absolute power in the LF and HF frequency bands, respectively. Base-10 logarithmic units. While the exercise depressed both LF and HF power, WBC selectively enhanced HF power. Data expressed as mean ± standard error; significant differences marked by *