Take a siesta to reduce your blood pressureNovember 14th, 2007 - 2:16 am ICT by admin
Afternoon naps, or siestas are typically short naps or rest periods of no more than an hour that are taken in the afternoon.
While earlier studies on siestas have found that this practice may slightly increase the risk of heart attack, the new study has shown an inverse relationship between siesta taking and fatal heart attacks.
According to the researchers, change in blood pressure is the key factor linking afternoon naps to cardiovascular function. Some researchers hypothesize that the lower blood pressure reduces strain on the heart and decreases the risk of a fatal heart attack.
The current study provides a detailed description of changes in cardiovascular function of daytime sleep in healthy individuals, comparing napping with other daytime activities such as standing and lying down without going to sleep.
For the study, the researchers tested nine healthy volunteers (eight men, one woman) who did not routinely take afternoon naps. The volunteers wore equipment that checked blood pressure, heart rate, and forearm cutaneous vascular conductance (which determines dilation of blood vessels).
During one afternoon session, the volunteer spent an hour resting, lying face-up in bed. During another session, the volunteer spent an hour relaxed, but standing. And in one session, the volunteer was allowed an hour to sleep, lying face-up. During the sleep stage, the researchers measured the volunteer’s different stages of sleep.
After analysis, researchers found a significant drop in blood pressure during the sleep trial, but not during the resting or standing trials. Besides, this drop in blood pressure occurred mostly after lights out, just before the volunteer fell asleep.
According to the John Moores team, this fall in blood pressure may be one explanation for the lower cardiovascular mortality that some studies have found among people who habitually take siestas. On the other hand, some studies of nocturnal sleep have shown that blood pressure rises when we awake and that more cardiac deaths occur in the mornings.
Hence, the team will next look at blood pressure during the waking portion of the afternoon nap to see if this period may also pose an increased danger of coronary mortality.
The study entitled, ‘Acute Changes in Cardiovascular Function During the Onset Period of Daytime Sleep: Comparison to Lying Awake and Standing,’ is published in the online edition of the Journal of Applied Physiology, published by The American Physiological Society. (ANI)
- Daytime nap is good for your heart: Study - Mar 01, 2011
- Sleep deprivation can cause night-time urination in kids - Feb 02, 2012
- Hour of daytime sleep can lower blood pressure - Mar 01, 2011
- 'Patients losing sleep over BP monitors' - Dec 18, 2009
- Daytime naps could be early sign of dementia - Jul 17, 2012
- Sleep apnea treatment staves off heart failure - Mar 14, 2012
- Late nights 'increase risk of strokes, heart attacks' - Feb 09, 2011
- Sleep disorder linked to elderly men's blood pressure - Aug 31, 2011
- Trouble falling asleep signals heart attack risk - Oct 31, 2011
- Sleep disorder doubles cancer risk - Sep 05, 2012
- Sleeping pills harmful in long run - Aug 10, 2012
- Stress could tell harder on women's hearts - Apr 25, 2012
- Beware that broken heart after bereavement - Jan 10, 2012
- Insomniacs prime candidates for hypertension: Study - Jun 07, 2012
- Poor sleep ups risk of heart disease, stroke: Study - Nov 15, 2010
Tags: afternoon naps, beneficial, cardiovascular diseases, cardiovascular function, different stages of sleep, drop in blood pressure, fatal heart, have discovered that, heart attack, heart attacks, heart rate, hypothesize, john moores university, liverpool john moores, liverpool john moores university, reducing blood pressure, risk, stages of sleep, volunteer, volunteers