Purple patch? Beetroot emerges as nature's performance enhancer
If you see an athlete with purple stains on their lips during this
summer's Olympics, they may be taking the latest performance enhancer -
A soon-to-be-published study of climbers in the Alps who were given
beetroot juice to drink is expected to show that it boosted the
efficiency in which their bodies used oxygen.
The study is part of a series investigating the effects of altitude
on the body which leads to oxygen deprivation similar to that
experienced by patients suffering from critical illness.
Researchers from the Centre for Altitude, Space and Extreme
Environment Medicine (Case) at University College, London, say the
insights they have gained from studying elite climbers are helping to
improve treatment of patients in intensive care.
Blood samples taken at the top of Everest showed some of the climbers
had blood oxygen levels so low they were previously thought to be
incompatible with life. Now, in a £1m study over five years, funded by
the National Institute for Health Research, experts will examine these
"good adaptors" (to altitude) for biomarkers in their blood that could
help identify patients able to tolerate low levels of oxygen.
Mike Grocott, professor of critical care medicine at Southampton
University, who is leading the research said: "What we want to know is
who is a good adaptor [to low oxygen levels] and why."
A critically ill patient who was a good adaptor would not need as
high an oxygen level as a person who was a poor adaptor, so treatment
could be adjusted and the effects of ventilation avoided. "We often give
oxygen to keep people alive. But using mechanical ventilation harms the
lungs. If you can turn the ventilator down, because the patient you are
treating can manage on a lower level of oxygen, that is a benefit."
A second study, of climbers who ascended to an altitude of 4,500
metres in the Alps, found changes in the microcirculation and in the
metabolism of the body's cells. "The capillaries don't work as well and
the cells go into hibernation - where there is less oxygen they close
down so they don't use as much," Professor Grocott said.
The change is linked with the level of nitric oxide in the blood,
raising the possibility that by taking nitrate supplements it may be
possible to counter the effects of oxygen deprivation - at altitude and
in critical illness. Beetroot is rich in nitrates and other researchers
have found it boosts stamina.
As a former head of Case and leader of Xtreme Everest, he will lead
an expedition to Everest Base Camp next year to examine the Tibetan
sherpas who work there and compare their physiology with that of regular
high altitude climbers and those arriving on the mountain for the first
- The Independent