Effects of music on cardiorespiratory function, perceived exertion and acute mountain sickness symptoms in simulated high altitude environment / Alzamani Mohammad Idrose

Music had been used for exercise as well as sports performance enhancement, and has
the potential to reduce the risk of altitude illness. This study investigated the effects of
music listening on cardiorespiratory function, perceived exertion and acute mountain
sickness (AMS) at high altitude. In a cross-over study design, eleven (n=11) male
participants (age: 27.73 ± 3.29 years; weight: 66.14 ± 8.13 kg; height: 167.91 ± 3.65
cm) underwent three types of interventions: no music (NM), relaxing music (RM) and
arousal music (AM). Each group was exposed to simulated hypoxic condition (5000 m)
in a hypobaric chamber with one week washout period in between intervention. The
cardiac function was assessed using blood pressure (BP), heart rate (HR) and
echocardiogram. The respiratory function was evaluated using respiratory rate (RR),
pulse oximeter (SpO2), spirometer and lung ultrasound (B-lines for fluids leakage). The
rate of perceived exertion (RPE) was measured using Category-Ratio (CR10) Borg
scale whereas the Acute Mountain Sickness(AMS) symptoms were assessed using Lake
Louise Score (LLS). These measurements were recorded at the sea level (SL), 3000m
and 5000m. Significant effects of music (p<0.05) were seen on HR, EF, SpO2, B-lines
appearance on lung ultrasound, RPE and LLS. For the HR, the mean was 80.45 + 16.54,
75.82 + 10.39 and 80.00 + 14.18 bpm at SL, 3000 and 5000m respectively in NM
group. Significant difference was seen in AM group when compared to NM with
decreased HR by 16.16%, 3.24% and 7.83% at SL, 3000 and 5000m respectively (p
=0.021). For the EF, the mean was 65.50 ± 6.03%, 57.29 + 7.21% and 58.06 + 8.99%
at SL, 3000 and 5000m respectively in NM group. Significant difference of EF were
seen in AM group when compared to NM with reduction by 18.29%, 0.31% and 4.50%
at SL, 3000 and 5000m respectively (p=0.013). For SpO2, at SL, the mean was 97.36 ±
1.12 % with NM and this decreased by 0.45% with RM; but higher by 1.19% with AM.
At 3000m, the SpO2 was 87.45 + 4.08% with NM, but higher by 5.00% and 4.46%
with RM and AM respectively. At 5000m, it was 75.82 + 11.40% with NM but higher
by 2.27% and 5.27% in the RM and AM groups respectively. Significant difference was
seen in AM (p=0.020) and RM (p=0.032) groups when compared to NM. For B-lines,
with NM, the mean number of lines were 0, 1.55 ± 0.93 and 3.36 ± 1.50 at SL, 3000
and 5000m respectively. There were reductions by 88.38% and 94.64% of lines with
RM compared to NM, at 3000 and 5000m respectively (p<0.001). With AM, there were
reductions by 41.29% and 72.91% at similar respective altitudes (p=0.001). The mean
RPE scores were 6.00 ± 1.73, 3.27 ± 0.79 and 3.55 ± 1.04 in NM, AM and RM groups
respectively with significant difference seen in AM (p=0.004) and RM (p=0.002)
groups when compared to NM. The mean LLS were 4.55 ± 2.25, 1.55 ± 1.64 and 1.55
± 1.63 in NM, AM and RM group respectively with significant difference seen in AM
(0.002) and RM (p=0.037) groups. In conclusion, this study showed that in a simulated
high altitude environment, exposure to AM showed significant reduction of mean HR
and EF. Both AM and RM exposure resulted in significantly higher SpO2, less number
of 'B-lines' on lung ultrasound, less AMS symptoms and less RPE scores. Music
exposure could potentially benefit high altitude climbers in terms of less AMS
symptoms, less RPE, better SpO2 and less fluids leakage into lung tissues. Music
exposure provided favourable physiological changes in high altitude environment,
which may have implications to reduce the risk of AMS.