Key result
Sauna bathing alone or after exercise significantly increased low-frequency and decreased high-frequency heart rate variability (P<.05) in untreated hypertension, normalizing within 120 minutes.
Why the study?
Does sauna bathing alone or after exercise alter short-term heart rate variability in patients with untreated hypertension?
RCT (n=10)
randomly assigned
Does sauna bathing alone or after exercise alter short-term heart rate variability in patients with untreated hypertension?
p-value: p=<.05
A single sauna session transiently increases sympathetic and decreases parasympathetic drive in patients with untreated hypertension, with normalization within 2 hours.
Clinicians should note transient sympathetic dominance after sauna in untreated hypertension; extends RCT evidence on acute autonomic effects of heat exposure.
In Brief PURPOSE: We measured the effects of sauna bathing alone or a 30-minute exercise session followed by sauna bathing on short-term heart rate variability (HRV) in subjects with untreated hypertension. METHODS: Ten patients with untreated hypertension (age 59 ± 10 years) were randomly assigned to (1) a control resting session, (2) two 8-minute sauna-only sessions (S), or (3) a 30-minute aerobic exercise session at 75% of maximal heart rate followed by a sauna session (ES). Spectral analysis of HRV was measured with a Polar S810 heart rate monitor at baseline, during the sauna session, and 15 and 120 minutes after the sauna session (T15 and T120). A Fast Fourier Transformation was used to quantify the power spectral density of the low-frequency (LF) and high-frequency (HF) bands. RESULTS: For S and ES conditions, LF (NU, normalized unit) and LF/HF were significantly higher (P < .05 and P < .01) in the first and second sauna sessions, and HF (NU) was significantly lower (P < .05, first sauna). At baseline and T15 for S and ES versus control, LF (NU) and LF/HF were significantly higher (P < .05), and HF (NU) was significantly lower (P < .05), without any effect of the 30-minute exercise session. CONCLUSIONS: A single sauna session induced a significant alteration of autonomic cardiovascular control in patients with untreated hypertension, with an increased sympathetic and decreased parasympathetic drive. These alterations were normalized within 15 to 120 minutes after sauna bathing. Additional studies are required to document long-term effects of chronic sauna bathing on autonomic control in patients with hypertension. The effects of sauna bathing alone or an exercise session followed by sauna bathing on heart rate variability spectral parameters (high and low frequencies) were measured in 10 patients with untreated hypertension. An increased sympathetic and decreased parasympathetic drive occurred during sauna bathing, with normalization 15 to 120 minutes after sauna bathing.
No takes yet. Share an insight, caveat, or question.
Gayda et al. (2012) conducted an RCT in untreated hypertension (n=10). Sauna bathing alone or postexercise sauna bathing vs. Control resting session was evaluated on Short-term heart rate variability (low-frequency and high-frequency bands) (p=<.05). Sauna bathing alone or after exercise significantly increased low-frequency and decreased high-frequency heart rate variability (P<.05) in untreated hypertension, normalizing within 120 minutes.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: